Search

As the COVID-19 pandemic continues to evolve, different clinical manifestations are better understood and studied. These include various haematologic disorders that have been shown to be associated with increased morbidity and mortality. We studied the prevalence of one unusual manifestation, heparin-induced thrombocytopenia (HIT) and its clinical implications in patients who are severely ill with COVID-19 in a single tertiary centre in Israel. The presence of thrombocytopenia, disseminated intravascular coagulation (DIC) and HIT, and their association with clinical course and outcomes were studied. One-hundred and seven patients with COVID-19 were included. Fifty-seven (53.2%) patients developed thrombocytopenia, which was associated with the worst outcomes (ventilation, DIC and increased mortality). Sixteen (28.0%) patients with thrombocytopenia were positive for HIT, all of which were supported by extracorporeal devices. HIT was independently associated with ventilation days, blood product transfusions, longer hospitalisation and mortality. Platelet abnormalities and HIT are common in patients who are critically ill with COVID-19 and are associated with the worst clinical outcomes. The mechanisms underlying HIT in COVID-19 are yet to be studied; HIT may contribute to the dysregulated immunologic response associated with COVID-19 critical illness and may play a significant part in the coagulopathy seen in these patients. As many patients with COVID-19 require aggressive thromboprophylaxis, further understanding of HIT and the implementation of appropriate protocols are important.

ObjectivesUS FDA and EMA allow facilitated regulatory pathways to expedite access to new treatments. Limited supportive data may result in major postapproval variations. In Israel, partly relying on Food and Drug Administration (FDA) and European Medicines Agency (EMA), clinical data are reviewed independently by the Advisory Committee of Drug Registration (ACDR). In this study, the correlation between the number of discussions at the ACDR and major postapproval variations is examined.DesignThis is an observational retrospective comparative cohort study.SettingApplications with FDA and/or EMA approval at time of assessment in Israel were included. The timeframe was chosen to allow a minimum of 3 years of postmarketing approval experience for potential major label variations. Data regarding the number of discussions at ACDR were extracted from protocols. Data on postapproval major variations were extracted from the FDA and EMA websites.ResultsBetween 2014 and 2016, 226 (176 drugs) applications, met the study criteria. 198 (87.6%) and 28 (12.4%) were approved following single and multiple discussions, respectively. A major postapproval variation was recorded in 129 (65.2%) compared with 23 (82.1%) applications approved following single and multiple discussions, respectively (p=0.002). Increased risk for major variation was found for medicines approved following multiple discussions (HR=1.98, 95% CI: 1.26 to 3.09) with a median time of 1.2 years, applications approved based on phase II trials (HR=2.58, 95% CI: 1.72 to 3.87), surrogate endpoints (HR=1.99, 95% CI: 1.44 to 2.74) and oncologic indications (HR=2.48, 95% CI: 1.78 to 3.45).ConclusionsMultiple ACDR discussions associated with limited supportive data are predictive for major postapproval variations. Moreover, our findings demonstrate that approval by the FDA and/or EMA does not pave the way to automatic approval in Israel. In a substantial per cent of the cases, submission of the same clinical data resulted in different safety and efficacy considerations, requiring additional supporting data in some cases or even rejection of the application in others.

IntroductionUnprovoked pulmonary embolism (UPE) is not rare and it is associated with an unfavorable prognosis in adults. However, the incidence and the prognosis of UPE in older adults have never been studied.Material and methodsThis was a historical prospective study. We reviewed all the medical charts of all older adults (aged 70 years or more) with UPE, provoked pulmonary embolism (PPE), and malignancy-associated PE (MAPE), admitted to a tertiary medical center between 2010 and 2012. The all-cause 3-year mortality rates and cumulative survival following admission were compared between the groups.ResultsThe final cohort included 249 patients with PE: 161 (64.7%) were women; the mean age was 79.8 ±5.7 years. Overall, 36 (14.5%) patients had UPE, 81 (32.5%) patients had MAPE, and 132 (53.0%) patients had PPE. Overall, 39 (15.7%) patients died within 30 days, 76 (30.5%) patients died within 6 months, 101 (40.6%) patients died within 1 year, and 136 (54.6%) patients died within 3 years of admission. Relative to PPE and MAPE patients, the cumulative survival was significantly higher in UPE patients at each time point within 1 year of admission (p < 0.05 and p < 0.001, respectively). However, 3 years after admission, the cumulative survival was comparable between PPE patients and UPE patients, and was significantly lower in MAPE patients (p < 0.001).ConclusionsUPE is not rare in older adults with PE, and it is associated with a favorable prognosis within 1 year of admission in this population.

Objectives The aim was to compare the burden of environmental shedding of toxigenic Clostridioides difficile among asymptomatic carriers, C. difficile-infected (CDI) patients and non-carriers in an inpatient non-epidemic setting. Methods C. difficile carriage was determined by positive toxin-B PCR from rectal swabs of asymptomatic patients. Active CDI was defined as a positive two-step enzyme immunoassay/polymerase chain reaction (EIA/PCR) test in patients with more than three unformed stools/24 hr. C. difficile environmental contamination was assessed by obtaining specimens from ten sites in the patients' rooms. Toxigenic strains were identified by PCR. We created a contamination scale to define the overall level of room contamination that ranged from clean to heavy contamination. Results One hundred and seventeen rooms were screened: 70 rooms inhabited by C. difficile carriers, 30 rooms by active CDI patients and 17 rooms by non C. difficile -carriers (control). In the carrier rooms 29 (41%) had more than residual contamination, from which 17 (24%) were heavily contaminated. In the CDI rooms 12 (40%) had more than residual contamination from which three (10%) were heavily contaminated, while in the control rooms, one room (6%) had more than residual contamination and none were heavily contaminated. In a multivariate analysis, the contamination score of rooms inhabited by carriers did not differ from rooms of CDI patients, yet both were significantly more contaminated than those of non-carriers odd ratio 12.23 and 11.16 (95% confidence interval 1.5–99.96 p 0.0195, and 1.19–104.49 p 0.035), respectively. Discussion Here we show that the rooms of C. difficile carriers are as contaminated as those of patients with active CDI and significantly more than those of non-carriers.

As the coronavirus pandemic emerged in late 2019, a task force was founded in the Sheba Medical Center and began preparing for the arrival of the pandemic to Israel. Several wards were put in charge of isolated COVID-19 patients. A new intensive care unit was formed for the most critical COVID-19 patients, requiring mechanical ventilation and multi-organ treatment. The Corona ICU began operating in March 2020, with a multi-disciplinary team, gathered from ICU units, an internal medicine ward, an anesthesiology department, social workers and psychologists. Simultaneously, the routine medical center functions in non-corona sections were maintained, as much as possible. The coronavirus pandemic entails challenges of many aspects: an unfamiliar pathogen causing an unknown illness, a necessity for social distancing, ambiguity regarding the risk factors for contamination and illness severity, and medical crews put at risk. Consequently, the pandemic involves ethical, social, economic and moral aspects, affecting the medical crew members and system, the patients and their families, and our society as a whole. In this article we review our joint experience in the Sheba Medical Center Corona ICU, of the medical, ethical and moral dilemmas that emerged from the first COVID-19 wave.

Rapid and sensitive screening tools for SARS-CoV-2 infection are essential to limit the spread of COVID-19 and to properly allocate national resources. Here, we developed a new point-of-care, non-contact thermal imaging tool to detect COVID-19, based on image-processing algorithms and machine learning analysis. We captured thermal images of the back of individuals with and without COVID-19 using a portable thermal camera that connects directly to smartphones. Our novel image processing algorithms automatically extracted multiple texture and shape features of the thermal images and achieved an area under the curve (AUC) of 0.85 in detecting COVID-19 with up to 92% sensitivity. Thermal imaging scores were inversely correlated with clinical variables associated with COVID-19 disease progression. We show, for the first time, that a hand-held thermal imaging device can be used to detect COVID-19. Non-invasive thermal imaging could be used to screen for COVID-19 in out-of-hospital settings, especially in low-income regions with limited imaging resources.HIGHLIGHTSAutomated processing of thermal images of the back can be used to detect COVID-19 with up to 92% sensitivity.The extracted texture features of the thermal image are associated with COVID-19 disease progression and lung injury.A portable thermal camera that connects directly to smartphones can be used to detect COVID-19.Non-invasive thermal imaging could be used to screen for COVID-19 in out-of-hospital settings and regions with limited imaging resources.GRAPHICAL ABSTRACT

Background Although coronavirus disease 2019 (COVID-19) causes significan t morbidity, mainly from pulmonary involvement, extrapulmonary symptoms are also major componen ts of the disease. Kidney disease, usually presenting as AKI, is particularly severe among patients with COVID-19. It is unknown, however, whether such injury results from direct kidney infection with COVID-19's causative virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), or from indirect mechanisms. Methods Using ex vivo cell models, we sought to analyze SARS-CoV-2 interactions with kidney tubular cells and assess direct tubular injury. These models comprised primary human kidney epithelial cells (derived from nephrectomies) and grown as either proliferating monolayers or quiescent three-dimensional kidney spheroids. Results We demonstrated that viral entry molecules and high baseline levels of type 1 IFN-related molecules were present in monolayers and kidney spheroids. Although both models support viral infection and replication, they did not exhibit a cytopathic effect and cell death, outcomes that were strongly present in SARS-CoV-2-infected controls (African green monkey kidney clone E6 [Vero E6] cultures). A comparison of monolayer and spheroid cultures demonstrated higher infectivity and replication of SARS-CoV-2 in actively proliferating monolayers, although the spheroid cultures exhibited high er levels of ACE2. Monolayers exhibited elevation of some tubular injury molecules-including molecules related to fibrosis (COL1A1 and STAT6) and dedifferentiation (SNAI2)-and a loss of cell identity, evident by reduction in megalin (LRP2). The three-dimensional spheroids were less prone to such injury. Conclusions SARS-CoV-2 can infect kidney cells without a cytopathic effect. AKI-induced cellular proliferation may potentially intensify infectivity and tubular damage by SARS-CoV-2, suggesting that early intervention in AKI is warranted to help minimize kidney infection.

People from different cultures are often hospitalized while the staff treating them do not have sufficient knowledge about the attitudes and feelings of the patients regarding culture and health. To fill this gap, the aim of this study was to examine the perspective of Israeli older adult hospital in-patients regarding the association between health and culture and to understand the meaning of the participants’ experiences with regards to the medical staff’s attitude towards them. This study was carried out using qualitative methodology that followed the interpretive interactionism approach. The research participants were 493 (mean age 70.81, S.D.: 15.88) in-patients at internal care departments at a hospital in Israel who answered an open-ended question included in the questionnaire as part of a wide study held during 2017 to 2018. Two main themes were found: (1) a humane attitude of respect and the right to privacy and (2) beliefs, values, and traditional medicine that are passed down through generations. The findings highlighted the issue of the patients’ cultural heritage and ageist attitudes they ascribed to the professional staff. This study provided recommendations for training the in-patient hospital workforce on the topic of cultural competence, beginning from the stage of diagnosis through treatment and to discharge from the hospital, in order to improve the service.

Background: Familial hyperkalemia and hypertension (FHHt) is an inherited disorder manifested by hyperkalemia and hypertension. The following four causative genes were identified: WNK1, WNK4, CUL3, and KLHL3. For the first 3 genes, inheritance is autosomal dominant. For KLHL3, inheritance is mostly dominant. A few cases with autosomal recessive disease were described. The mechanism of these 2 modes of inheritance is not clear. In the recessive form, the phenotype of heterozygotes is not well described. Methods: Clinical and genetic investigation of members of 2 families was performed, one with recessive FHHt, and the other, an expansion of a family with Q309R KLHL3 dominant mutation, previously reported by us. Urinary exosomal sodium chloride cotransporter (NCC) was measured. Results: A family with recessive FHHt caused by a new KLHL3 mutation, S553L, is described. This consanguineous Jewish family of Yemenite extraction, included 2 homozygous and 7 heterozygous affected subjects. Increased urinary NCC was found in the affected members of the family with dominant Q309R KLHL3 mutation. In the recessive S553L family, homozygotes appeared to have increased urinary NCC abundance. Surprisingly, heterozygotes seemed to have also increased urinary NCC, though at an apparently lower degree. This was not accompanied by a clinical phenotype. Conclusions: A new recessive mutation in KLHL3 (S553L) was identified in FHHt. Increased urinary NCC was found in affected members (heterozygous) with dominant KLHL3 Q309R, and in affected members (homozygous) of the recessive form. Unexpectedly, in the recessive disease, heterozygotes seemed to have increased urinary NCC as well, apparently not sufficient quantitatively to produce a clinical phenotype.

Familial hyperkalemia and hypertension (FHHt) is an inherited disease characterized by hyperkalemia, hypertension, and hyperchloremic acidosis (1, 2). The primary defect is a hyperactive sodium chloride cotransporter (NCC), expressed exclusively in renal distal convoluted tubule (DCT). FHHt is caused by a mutation in 1 of 4 genes, WNK1, WNK4, KLHL3, and Cul3, which leads to activation of NCC (2). A recent publication in PNAS (3) shows that a mutation of WNK4 prevents specific modulation by Cl− ions, inhibits its activity, and produces a FHHt phenotype. This emphasizes the significant role of WNK4 in renal Cl− handling in pathogenesis of FHHt and the question of the mechanism of hyperchloremic metabolic acidosis (4). Is hyperchloremia in FHHt a primary abnormality … [↵][1]1To whom correspondence may be addressed. Email: farfel{at}post.tau.ac.il. [1]: #xref-corresp-1-1

5-oxoprolinemia (pyroglutamic acid, PGA) in the absence of acetaminophen use has been rarely reported as a cause for high anion gap metabolic acidosis. We investigated the prevalence and risk factors for elevated PGA concentrations among hospitalized patients with high anion gap metabolic acidosis: We prospectively enrolled patients with high anion gap metabolic acidosis hospitalized in the department of medicine. For each patient we collected the main diagnosis, concurrent medications and laboratory parameters. Spot urine samples were tested for PGA concentration. Levels ≥63 µmol/mmol creatinine were considered elevated. Overall, forty patients were prospectively followed. Mean age was 66.9 (17.9) years. Four (6.3%) patients had a high urine PGA level and demonstrated also lower blood pH (7.2 vs 7.3, p = 0.05) and lower serum lactate concentration (17.5 mg/dl vs 23.0 mg/dl, p = 0.04). Additionally, the high PGA level group consisted of more patients with septic shock [2/4 (50%) vs 3/36 (8.3%)] with a trend towards significance (p = 0.07). In conclusion, PGA might have a role in patients with septic shock and acidosis. Being a treatable condition, PGA should be taken into consideration particularly when no other cause for high anion gap is identified.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Background: Familial hyperkalemia and hypertension (FHHt) is a rare genetic disorder manifested by hyperkalemia and early hypertension. Hypercalciuria is another accompanying feature. Mutations in WNK4 and WNK1 were found initially, and recently additional mutations were found in two genes, KLHL3 and CUL3, which are components of the Ubiquitin system. It was not reported whether these latter mutations are accompanied by hypercalciuria. Methods: We compared urinary calcium excretion (UCa) in affected subjects with FHHt and KLHL3 mutations, and in their unaffected family members, and in affected subjects with FHHt and WNK4 Q565E mutation. Results: Two new families with FHHt including a total number of 23 subjects, 10 of them affected, in whom previously described mutations in KLHL3 (Q309R and R528H) were identified. Presenting features were short stature in the first family, and transient tachypnea of the newborn (TTN) in the second. Affected subjects had hypercalciuria. UCa levels in affected subjects in the two families were significantly higher than in unaffected subjects (0.608 ± 0.196 vs. 0.236 ± 0.053 mmol Ca per mmol creatinine, respectively (p < 0.0001)). Hypercalciuria in FHHt with KLHL3 mutations is less severe than that observed in FHHt with the Q565E WNK4 mutation (0.608 ± 0.196 (n = 10) mmol Ca per mmol creatinine versus 0.860 ± 0.295 (n = 29), respectively (p = 0.0168)). Conclusions: FHHt caused by KLHL3 mutations is accompanied by hypercalciuria as well as hyperkalemia and hypertension. The similar phenomena observed for FHHt caused by WNK4 mutations fits the other evidence that WNK4 mutations are activating, and the aberrant mechanism of calcium handling by the kidney in FHHt.

Objective Low dose (10–25 mg/week) methotrexate is widely used for the management of systemic inflammatory diseases, and is considered to be relatively safe. Toxicity due to low dose MTX has been reported but is poorly characterized. We describe the clinical features, risk factors, and outcomes of low dose MTX toxicity in a large case series at our center. Patients and methods We conducted a retrospective case series of all adult (> 18 years) patients hospitalized at Sheba Medical Center, between 2005 and 2012 for low dose MTX toxicity. Results We identified 28 patients (age: 70.4 ± 13.7 years, range: 33–88; 20 (71%) females) hospitalized for low dose MTX toxicity. Indications for MTX therapy included: rheumatoid arthritis (39.2%), psoriasis ± arthritis (21.5%), polymyalgia rheumatica (10.8%) and other inflammatory conditions (28.5%). Pancytopenia was the most common manifestation of low dose MTX toxicity detected in 78.5% of the patients. Potential risk factors included acute renal failure, hypoalbuminemia, concurrent use of drugs known to interact with MTX, and dose errors. Serum MTX concentrations (n = 20, mean 0.04 ± 0.07 μg/mL range: 0–0.3) did not correlate with the degree of either neutropenia (r = − 0.36; p = 0.18) or thrombocytopenia (r = 0.44; p = 0.10). Seven (25%) patients died, all from pancytopenia followed by sepsis. Serum MTX concentrations did not differ between the patients who died from MTX toxicity (n = 6; mean: 0.05 ± 0.04 μg/mL) and those who survived the toxicity (n = 14 mean 0.04 ± 0.08; p = 0.45). Conclusions Low-dose MTX toxicity can be life threatening, mainly due to myelosuppression. There is no rationale for MTX therapeutic drug monitoring in the setting of low-dose toxicity.

Background: Hypomagnesemia is a known predisposing condition for the appearance of digitalis toxicity. The detection of a genetic form of Mg urinary wasting with hypomagnesemia being caused by a mutation in the γ subunit (FXYD2) of the Na,K-ATPase, the pharmacological target of Digoxin, prompted us to investigate whether Digoxin administration increases urinary Mg excretion. Methods: Two groups of subjects, with rapid atrial fibrillation, received intravenous Digoxin (n = 9) or verapamil (n = 8), for heart rate control. During the following 4 h, blood and urinary creatinine, sodium, potassium, calcium, and magnesium levels were determined, and fractional excretion (Fex) values for Na, K, Ca, and Mg were calculated. Results: In the Digoxin group, at 60 min Fex Mg rose from 3.07 ± 1.21 to 7.58 ± 2.51% (an increase of 269 ± 107% of baseline, p < 0.001), and at 240 min to 6.05 ± 2.30% (204 ± 56% of baseline, p < 0.01). No significant change was observed for Fex Na, Fex K, and Fex Ca. A striking correlation was found between individual values of Fex Mg and serum Digoxin concentration (r = 0.678, p < 0.0001). No significant correlation was found between Fex Na or Fex K and serum Digoxin. A correlation of borderline significance was found between Fex Ca and serum Digoxin (r = 0.349, p = 0.073). Conclusions: The hypermagnesuric effect of acute Digoxin treatment is reminiscent of the effect of the missense mutation in FXYD2, which assumes that FXYD2 is a positive regulator of Na,K-ATPase in the distal convoluted tubule (DCT). The borderline calciuric effect of Digoxin may point to an additional site of action, more proximal to the DCT, that is, the thick ascending limb.

Little is known about the prognosis associated with statin therapy and its gender differences in older adults aged ≥80 years. To study the mortality and survival associated with statin therapy and their gender differences in older adults aged ≥80 years. This was a historical prospective study conducted at a tertiary medical center. The medical charts of all older adults aged ≥80 years who had been admitted to a single internal medicine department during 1 year were reviewed. All-cause 3‑year mortality and survival rates following hospital admission in men and in women using statins were investigated. The final cohort included 216 patients: 122 (56.5%) women, mean age 85.3 ± 3.9 years. Overall, 66 (53.2%) women and 58 (46.8%) men used statins for 3 years or more following hospital admission. During this time 48 (39.3%) women and 48 (51.1%) men died. The all-cause 3‑year mortality rates were significantly lower only in women who had used statins compared with women who had not used statins (24.2% vs. 57.1%; relative risk = 0.2; 95% confidence interval 0.1–0.5; p < 0.0001). The 3‑year cumulative survival rates were significantly higher in women who had used statins as part of primary as well as secondary cardiovascular prevention (p < 0.0001 and p = 0.014, respectively). A Cox regression analysis showed that statin therapy was independently associated with low 3‑year cumulative mortality rates in women (hazard ratio=0.3; 95% confidence interval=0.1–0.6; p = 0.001). In older adults aged ≥80 years, statin therapy is associated with high 3‑year cumulative survival rates only in women.

Recurrent hospitalizations with hyponatremia are commonly encountered in older adults admitted to Internal Medicine wards. However, the incidence and the prognostic implication of this phenomenon have never been studied.Medical charts of all older adults (≥75 years) admitted to Internal Medicine wards at a tertiary medical center during 2009-2010 with symptomatic moderate to severe hyponatremia (blood sodium ≤130 meq/l) upon admission were reviewed. The study group included patients with one or more hospitalizations with hyponatremia in the year following the first hospitalization with hyponatremia. The control group included patients with a single hospitalization with hyponatremia. Mortality rates were studied one year following the second hospitalization with hyponatremia in the study group and one year following the single hospitalization with hyponatremia in the control group. Regression analysis was used to study the association between recurrent hospitalizations with hyponatremia and 1-year mortality while controlling for demographics, chronic co-morbidities, albumin serum levels, and the number of hospitalizations.The cohort included 431 older adults: 301 (69.8%) women; mean age of 84.6±5.6 years. Overall, 120 (27.8%) patients had recurrent hospitalizations with hyponatremia and 125 (29.0%) patients died within a year. 1-Year mortality rates were higher in patients with recurrent hospitalizations with hyponatremia than in patients with a single hospitalization with hyponatremia (42.5% vs. 23.8%; p0.0001). Regression analysis showed that recurrent hospitalizations with hyponatremia were independently associated with 1-year mortality (odds ratio 1.9; 95% confidence interval 1.1-3.2; p=0.018).Recurrent hospitalizations with hyponatremia in older adults are common and associated with 1-year mortality.

Background Cyclosporine is used for treatment of transplanted patients and for immune-mediated diseases. Cyclosporine is known to cause a combination of metabolic side effects including hypertension, hyperkalemia, hypercalciuria and hypomagnesemia. These side effects except for hypomagnesemia are the cardinal features of familial hyperkalemia and hypertension (FHHt), also called pseudohypoaldosteronism type II (PHA II). FHHt is caused by mutations in the kinases WNK1 and WNK4 resulting in an increase in renal Na-Cl cotransporter (NCC) apical distribution and function. Therefore, we studied whether cyclosporine’s metabolic side effects are mediated by WNK4 and NCC. Design Sprague-Dawley (SD) rats were treated by cyclosporine 25 mg kg )1 subcutaneously for 14 days. Blood pressure, blood chemistry values and kidney WNK4 protein were determined. In addition, mDCT cells were exposed to cyclosporine, and their WNK4 mRNA and protein content, and their NCC protein content and phosphorylation were determined. Results The rats developed an FHHt-like syndrome including hypertension, hyperkalemia and salt-sensitive hypercalciuria. A significant increase in their kidney WNK4 protein content (0AE13 ± 0AE01 vs. 0AE67 ± 0AE16 WNK4 ⁄ GAPDH in controls, P =0 AE0183) was found. In mDCT cells, cyclosporine caused a rise in WNK4 mRNA levels and also a threefold rise in WNK4 protein content. This rise was followed by a rise in NCC protein content and pSer71 phosphorylation. Conclusions These observations may explain in part the mechanism of cyclosporine-induced hypertension, hyperkalemia and hypercalciuria.

This article examines the central role of Na,K‐ATPase (α1β1FXYD2) in renal Mg handling, especially in distal convoluted tubule (DCT), the segment responsible for final regulation of Mg balance. By considering effects of Na,K‐ATPase on intracellular Na and K concentrations, and driving forces for Mg transport, we propose a consistent rationale explaining basal Mg reabsorption in DCT and altered Mg reabsorption in some human diseases. FXYD2 (γ subunit) is a regulatory subunit that adapts functional properties of Na,K‐ATPase to cellular requirements. Mutations in FXYD2 (G41R), and transcription factors (HNF‐1B and PCBD1) that affect FXYD2 expression are associated with hypomagnesemia with hypermagnesuria. These mutations result in impaired interactions of FXYD2 with Na,K‐ATPase. Renal Mg wasting implies that Na,K‐ATPase is inhibited, but in vitro studies show that FXYD2 itself inhibits Na,K‐ATPase activity, raising K0.5Na. However, FXYD2 also stabilizes the protein by amplifying specific interactions with phosphatidylserine and cholesterol within the membrane. Renal Mg wasting associated with impaired Na,K‐ATPase/FXYD2 interactions is explained simply by destabilization and inactivation of Na,K‐ATPase. We consider also the role of the Na,K‐ATPase in Mg (and Ca) handling in Gitelman syndrome and Familial hyperkalemia and hypertension (FHHt). Renal Mg handling serves as a convenient marker for Na,K‐ATPase activity in DCT.

Familial hyperkalemia and hypertension (FHHt) is caused by mutations in WNK kinases. Its pathogenesis is not completely understood.Our objective was to investigate the mechanism of hypercalciuria in FHHt.We conducted a study of a large family with FHHt and WNK4 Q565E mutation and of control subjects at a referral medical center.Forty-six members of a family with FHHt and WNK4 Q565E mutation, 23 of them affected, and 12 control subjects participated.Urinary calcium and sodium concentrations, endogenous lithium clearance, age of hypertension appearance were assessed.In 40 urine samples of 20 affected subjects, urinary calcium was correlated to urinary sodium (r = 0.567; P = 0.0001). In 28 urinary samples of 22 unaffected members, no correlation was found (r = 0.285; P = 0.14). Mean ratio of urinary calcium to urinary sodium was 2.7-fold higher in affected compared with unaffected members (58.7 +/- 25.9 vs. 22.1 +/- 14.0 micromol/mmol, P0.0001). Endogenous lithium clearance in eight affected members was about 50% lower than in 12 controls (16.2 +/- 7.7 vs. 28.8 +/- 9.8 ml/min, P = 0.0073). Hypertension was detected in males 12 yr earlier than in females (26.0 +/- 7.5 vs. 37.9 +/- 11.3 yr; P = 0.031).Hypercalciuria in FHHt seems to be dependent on urinary sodium. According to molecular studies, FHHt patients are presumed to have increased distal nephron sodium reabsorption and therefore decreased proximal reabsorption of sodium, lithium, and calcium. The observed decreased lithium clearance reflects probable abnormal renal handling of lithium, i.e. distal nephron lithium reabsorption. Therefore, hypercalciuria may result from proximal nephron aberration. Finally, earlier appearance of hypertension in males may be the result of sex-hormone activity.

WNK4 kinase mutations produce the autosomal dominant disorder familial hyperkalemia and hypertension (FHH), also known as pseudohypoaldosteronism type II, by a molecular mechanism that is not completely understood. In vitro experiments in frog oocytes showed that WNK4 affects ion transport systems such as the Na–Cl cotransporter and the renal outer medullary potassium channel. Some features of FHH suggest that long-term effects are involved in WNK4 signaling. In addition, WNK1 and WNK2, paralogs of WNK4, were shown to be involved in MAP kinase signaling. We therefore investigated possible WNK4 involvement in MAP kinase signaling. We stimulated HEK 293 cells overexpressing WNK4 by hypertonicity or using EGF, and measured phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 and p38. WNK4 augmented the phosphorylation of ERK1/2 and p38 in response to both hypertonicity and EGF. The FHH-producing and kinase-deficient mutants behaved similarly to wild-type WNK4. Hypertonicity stimulation was accompanied by cellular relocalization of WNK4 as manifested by its reversible disappearance from the supernatant fraction following extraction with a detergent-containing buffer. Live-cell microscopy showed that the cytoplasmic-soluble WNK4 redistributes rapidly to membrane-bound organelles, which, in the case of WNK1 kinase, were recently shown to represent trans-Golgi network/recycling endosomes. In contrast, EGF stimulation was not accompanied by redistribution of WNK4 as determined by cell fractionation or cell microscopy. The observation that WNK4-induced MAP kinase stimulation caused by hypertonicity, but not that caused by EGF, is associated with WNK4 subcellular redistribution suggests that this redistribution has a role in WNK4 signaling.

BACKGROUND WNK [With No K (lysine)] kinases are essential for regulation of blood pressure and potassium homeostasis. WNK4 expression was recently found not only in the distal nephron but also in chloride-transporting epithelia. To establish a physiological role for this distribution we studied patients with familial hyperkalaemia and hypertension (FHH), [pseudohypoaldosteronism type II (PHAII)], which is caused by mutations in WNK4. DESIGN Measurement of nasal potential difference (NPD) and sweat electrolytes were performed in controls, in six subjects with FHH and ten subjects with cystic fibrosis (CF). RESULTS Basal NPD was higher in FHH compared with controls (n = 20): 22.8 +/- 5.7 vs. 16.2 +/- 5.3 mV, respectively (P = 0.014). Maximal response to amiloride was also higher in FHH compared with controls: 14.8 +/- 3.5 vs. 10.0 +/- 4.8 mV, respectively (P = 0.03). In CF these values were 42.9 +/- 9.3 and 29.9 +/- 7.4 mV, respectively. The kinetics of the amiloride effect were faster in FHH, and as first reported here also in CF, compared with controls. At 30 s, amiloride-inhibitable residual PD in FHH was 50 +/- 30 vs. 81 +/- 9% in controls (P = 0.0003) and 56 +/- 7% in CF. The response to chloride-free and isoproterenol solutions, which determines chloride transport activity, was similar in FHH compared with controls [16.0 +/- 8.6 vs. 10.4 +/- 5.9 mV (P = 0.08)]. Sweat conductivity in FHH was 49.7 +/- 7.3 vs. 38.2 +/- 8.1 mmol (NaCl eq) L-1 in 16 controls (P = 0.007) and 94.0 +/- 19.3 in CF. CONCLUSIONS Mutant WNK4 increases Na+ transport in airways, and therefore it is regulated by wild-type WNK4. This may be caused by a regulation of ENaC or a K+ channel.

SUMMARY: Treating debilitated elderly patients through nasogastric tube (NGT) can change the pharmacokinetic characteristics of drugs, mainly those that are slow released (SR). The purpose of this study was to compare pharmacokinetic parameters between patients who receive SR theophylline orally and those who receive it through NGT. PATIENTS AND METHODS: The authors studied elderly patients in the geriatric ward receiving SR theophylline for chronic obstructive lung disease. In 17 patients fed by NGT (group I), theophylline was removed from the capsule and mixed with 10 mL of water. Group II included 15 patients who swallowed the drug orally. Theophylline blood levels were measured, as were peak concentration (C(max) ), time to peak (T(max) ), and area under the serum concentration-time curves (AUC). RESULTS: The mean daily dose was not statistically different between the two groups: 320 +/- 130 (200-500) mg/d in group I and 360 +/- 85 (200-500) mg/d in group II, given twice daily. All pharmacokinetic measurements were lower in group I as compared with group II: trough theophylline blood levels were 3.78 +/- 3.2 (0.5-10.77) microg/mL versus 8.63 +/- 4.6 (0-15.61) microg/mL ( P= 0.002); C(max) was 6.53 +/- 4.1 (1.3-13.33) microg/mL versus 10.51 +/- 3.30 (4.3-16.28) microg/mL (P = 0.0058), and AUC was 50.04 +/- 38.59 (11-112) microg/h/mL versus 80.37 +/- 28.8 (23-148) microg/h/ml (P = 0.024). CONCLUSIONS Patients receiving the drug through NGT had variability and unexpectedly low blood levels. Therefore, the pharmacokinetic parameters of SR preparations should be evaluated before their administration through NGT.

Objective To determine what triggers the use of digoxin therapeutic drug monitoring (TDM) that adheres to established indications and the change in digoxin dosage after the result of monitoring is obtained. Methods This prospective study included 86 patients admitted to 6 medicine wards and 2 intensive cardiac care unit wards in a tertiary-care center. Data on patients' demographics, drug therapy, serum chemistry values, indications for digoxin therapy, indications for ordering the drug assay, timing of the blood sample relative to administration of the last dose, and physicians' decisions after attaining serum digoxin concentrations were collected. Results Eighty-six digoxin assays were evaluated. Indications for the use of a digoxin assay were mostly routine without a clear indication (66%); in only 22% of the assays were orders considered clinically justified. Eleven patients had concentrations >2 ng/mL, but only 8 patients had digoxin intoxication. In only 31% of patients did the medical staff respond to the results. In only 21% of patients with subtherapeutic drug concentrations was there a change in digoxin dose. Conclusions Although there are clear indications for the use of digoxin TDM, physicians seem to routinely order these blood tests. The clinicians did not adequately use the digoxin concentration data to optimize therapy. The assistance of a clinical pharmacist or pharmacologist is warranted for use of the assays, to optimize digoxin therapy.

Hepatic infarction is a rare disease. We describe here a cirrhotic patient with end-stage renal failure and recurrent tense ascites with fatal hepatic infarction after transjugular intrahepatic portosystemic shunt (TIPS) procedure. Abdominal ultrasound, radionuclide liver scan, abdominal computed tomography scan, and finally liver biopsy established the diagnosis. The mechanism causing the infarct is not clear. However, as the infarct appeared after the patient had an episode of shock and disseminated intravascular coagulation, it could well be that the concomitant hepatic arterial insufficiency contributed to the infarct. Physicians should be aware of this possible catastrophic complication.

Hypertension is a major public health problem of largely unknown cause. Here, we identify two genes causing pseudohypoaldosteronism type II, a Mendelian trait featuring hypertension, increased renal salt reabsorption, and impaired K + and H + excretion. Both genes encode members of the WNK family of serine-threonine kinases. Disease-causing mutations in WNK1 are large intronic deletions that increase WNK1 expression. The mutations in WNK4 are missense, which cluster in a short, highly conserved segment of the encoded protein. Both proteins localize to the distal nephron, a kidney segment involved in salt, K + , and pH homeostasis. WNK1 is cytoplasmic, whereas WNK4 localizes to tight junctions. The WNK kinases and their associated signaling pathway(s) may offer new targets for the development of antihypertensive drugs.

Background: Trans-tubular potassium gradient (TTKG) is considered to reflect mainly aldosterone bioactivity with regard to its kaliuretic response. We determined both TTKG and aldosterone serum concentrations in patients with severe drug-induced hyperkalemia (DIH). Methods: Ten hyperkalemic patients with serum potassium of more than 5.5 mEq/l, and serum creatinine of less than 2.5 mg/dl (221 µmol/l) were studied prospectively. Two control groups of 10 patients each were used. Control 1 group with normal renal function, and control 2 group with normokalemia and renal failure of the same magnitude as that of the hyperkalemic patients. Serum osmolarity, electrolytes, creatinine, aldosterone and urine electrolytes and osmolarity were measured and TTKG calculated. Results: DIH patients had lower TTKG values than control 1 patients (2.58 ± 0.36 vs. 6.68 ± 0.55, p < 0.001), and also lower than that of the control 2 patients (2.58 ± 0.36 vs. 5.51 ± 0.87, p < 0.01). Serum aldosterone concentration in the DIH group was higher than that of the control 1 group [24.30 ± 5.0 vs. 7.4 ± 2.1 pg/ml (674 ± 139 vs. 205 ± 58 pmol/l), p < 0.006] but not different from that of the control 2 group [24.3 ± 5.0 vs. 15.3 ± 3.8 pg/ml (674 ± 139 vs. 424 ± 106 pmol/l), respectively, p = 0.18]. Although there was some overlap in TTKG between DIH and control groups, 6 of 10 DIH patients had TTKG of less than 2.5, while none of the control patients had such a low value. Conclusion: DIH is characterized by lower TTKG values than those observed in patients with normal or mild-to-moderate renal failure. Other factors in addition to aldosterone seem to be involved.

"Body packers" swallow multiple packets filled with illicit drugs, mainly cocaine, in order to smuggle them across international borders. In recent years, an increasing number of body packers have been hospitalized after their detention by the police upon arrival in Israel.To characterize the clinical features and outcomes of body packers hospitalized at the Sheba Medical Center.We conducted a retrospective case series of body packers hospitalized between January 2010 and October 2012 in our medical center. Electronic medical records and imaging files were reviewed to extract clinical, laboratory and radiological data as well as details on medical treatments.We identified 23 body packers (mean age 38 +/- 10 years), 20 of whom smuggled cocaine from South America. The number of packets transported ranged from 1 to 242 (median 42) and duration of hospitalization from 1 to 14 days (median 2). Two subjects required surgical intervention. All others were treated conservatively by polyethylene glycol-electrolyte lavage solution, laxatives, or watchful waiting. Ten patients underwent a urinary screen for illicit drugs, 7 of whom tested positive for cocaine and 2 for cannabinoids. Abdominal X-rays were performed in all patients at admission, and 14 had follow-up imaging, including abdominal CT scans without contrast media in 8.The main treatment goals for body packers are the rapid excretion of drug packets and early detection of complications, i.e., drug intoxication and bowel obstruction. We suggest the use of a structured treatment approach for the in-hospital management of body packers.

People without hemophilia but with autoantibodies specifically directed against the procoagulant activity of factor VIII are known to have acquired hemophilia. The bleeding diathesis in these patients is often severe and life-threatening. The definite laboratory diagnosis of this disorder includes demonstration of low factor VIII levels in plasma with a high titer of factor VIII inhibitors, but the initial suspicion for its presence should rise in view of a prolonged partial thromboblastin time (PTT) and a normal prothrombin time associated with an acquired bleeding disorder. Oral anticoagulant treatment is known to prolong PTT as well, and the merger of these 2 situations may cause delayed diagnosis of acquired hemophilia with devastating consequences. We describe here the first reported case of acquired hemophilia diagnosed in a patient treated with warfarin. In such patients prolonged PTT may be ascribed to warfarin therapy rather than to acquired hemophilia, thus causing a dangerous delay in diagnosis.

Emergency endotracheal and endobronchial drug administration provide an effective alternative for intravenous drug delivery during cardiopulmonary resuscitation. The purpose of the present study was to determine the immediate pharmacokinetic and pharmacodynamic properties of atropine following administration by either of these routes. Atropine (0.02 mg/kg) was given to seven anaesthetized mongrel dogs. Each dog was studied twice: once when atropine was injected into the endotracheal tube, and on another day when atropine was given via a flexible catheter wedged into a peripheral bronchus. Plasma atropine concentrations and blood gases were measured during 60 min following drug administration. Both routes of atropine administration differed significantly in three measures: the maximal atropine concentration (Cmax) was significantly higher with the endobronchial administration 40.0 +/- 7.8 ng/ml compared to 23.9 +/- 5 ng/ml endotracheally (P = 0.008); atropine's elimination (t1/2beta) half-life was significantly longer with the endobronchial route (39.3 +/- 5.2 min vs. 28.0 +/- 7.9 min; P = 0.05); Endobronchial administration resulted in an increase of 16% in heart rate, beginning immediately after drug delivery and peaking after 5 min. Other pharmacokinetic parameters were not significantly different. We conclude that endobronchial administration of atropine has a clear advantage over the endotracheal route.

Tolazoline is a potent vasodilator of arteries and veins and has a powerful effect on the pulmonary vasculature, reducing hypoxic pulmonary vasoconstriction and lowering pulmonary artery pressure. Intravenous tolazoline lowers the mean pulmonary arterial pressure and resistance and increases the cardiac index when given to infants with persistent pulmonary hypertension (PPHN). Endotracheally administered tolazoline decreases mean pulmonary arterial pressure and pulmonary vascular resistance, and improves oxygenation without the harmful decline in the systemic arterial pressure. The purpose of our study was to examine the pharmacokinetic and pharmacodynamic characteristics of endobronchial tolazoline to determine the relationship between endobronchial tolazoline administration, plasma concentration, and its effects on the cardiovascular and respiratory systems. Tolazoline was administered endobronchially to seven dogs, and its serum concentration and the hemodynamic parameters were monitored for 270 min postdelivery. It was found that 15 sec after dosing, tolazoline plasma concentrations started to increase significantly above baseline levels, reaching a maximum of 9.3+/-8.0 microg x mL(-1) The volume of distribution was 1657+/-321 mL x kg(-1) after 1 2.4+/-1 6.6 min. The extent of tolazoline absorption was 319+/-38 microg x min(-1) mL(-1). The total body clearance was 10.9 +/-4.8 mL x min(-1) x Kg(-1) and the elimination half-life was 156+/-81 min. Endobronchial tolazoline produced an initial short-lived decrease in the mean blood pressure in all the dogs, but thereafter the blood pressure increased gradually above baseline levels. Immediately following endobronchial tolazoline a significant tachycardia developed, peaking at 90 min. Subsequently, the heart rate gradually decreased and stabilized at values above baseline for 200 min. We conclude that an endobronchial bolus dose of tolazoline is effectively absorbed, produces measurable pharmacological effects, and may be beneficial in the therapy of persistent pulmonary hypertension of the newborn.

OBJECTIVE To report a case of acute pancreatitis in a patient receiving nilotinib for chronic myelogenous leukemia (CML). CASE SUMMARY A 69-year-old man recently diagnosed with chronic phase CML received nilotinib 300 mg twice daily and was admitted with acute pancreatitis that appeared the day after the first dose. The patient had normal levels of triglycerides and denied alcohol use. Serum pancreatic enzymes were within normal limits the day before nilotinib initiation. Abdominal computed tomography demonstrated a normal liver, bile duct without stones, and findings that were consistent with focal pancreatitis. The patient's history was significant for concomitant use of enalapril and simvastatin; both have been associated with pancreatitis, but the patient had been taking these medications for at least 5 years without adverse effects. Nilotinib was immediately discontinued. Abdominal pain resolved and serum pancreatic enzymes levels returned to normal 2 weeks later. DISCUSSION One of the adverse effects of some tyrosine kinase inhibitors is increased levels of serum pancreatic enzymes. Accordingly, nilotinib labeling includes “high lipase levels in serum” as an adverse event. There are few case reports of acute pancreatitis associated with nilotinib in the literature and some are incomplete. We present a well-documented case of nilotinib-associated acute pancreatitis. Consistent with Badalov's new classification system for drug-induced acute pancreatitis and with the Naranjo probability scale, this case represents a possible adverse reaction of pancreatitis associated with nilotinib therapy. As rechallenge is unethical, treatment with nilotinib has not been resumed. CONCLUSIONS This case demonstrates a possible association between acute pancreatitis and nilotinib use. Although a rare phenomenon, clinicians should be alert for signs and symptoms of pancreatitis, as treatment with nilotinib for CML is becoming more common.

The pituitary prohormone proopiomelanocortin gives rise to melanocortins of α, β, and γ primary structure in addition to corticotropin. Melanocortins have a variety of actions in mammals, and each is natriuretic. In particular, γ-melanocyte–stimulating hormone has been shown to mediate reflex natriuresis after acute unilateral nephrectomy. We examined whether this peptide could play a role in longer term adjustments in sodium balance by measuring plasma γ-melanocyte–stimulating hormone and corticotropin concentrations, as well as pituitary proopiomelanocortin mRNA abundance, in Sprague-Dawley rats ingesting either a low (0.07% NaCl) or high (7.5% NaCl) sodium diet. One week after the high sodium diet, plasma γ-melanocyte–stimulating hormone concentration was double the value seen in rats on the low sodium diet (158±5 [SE] versus 76±9 fmol/mL, P

Background Parathyroid hormone (PTH) secretion is regulated mainly by the calcium sensor receptor. Recently, other components of calcium homoeostasis have been revealed, namely the effect of Klotho on stimulation of PTH secretion by the recruitment of Na-K-ATPase and by its being a cofactor in the inhibitory effect of FGF 23 on PTH secretion. It seems that ouabain, a Na-K-ATPase inhibitor, prevents the increase in PTH secretion in a hypocalcemic environment, as observed in mouse and bovine tissues. We hypothesized that digoxin, which is similar to ouabain in its effect on the sodium pump, might decrease PTH levels in humans. Methods Twenty patients with atrial fibrillation were studied. Ten patients were treated with digoxin and the other ten patients with verapamil. Baseline chemistry parameters were determined and 0·25 mg digoxin injected. Plasma PTH concentrations, ionized calcium concentrations and digoxin levels were recorded at 30 min, 1 h, 2 h and 4 h postinjection. Results Baseline blood parameters were similar in both groups. In the control group plasma PTH concentrations increased, whereas in the digoxin group, they decreased. Ionized calcium concentrations did not change over time in either groups. There seemed to be blunting of the circadian rhythm of PTH levels in the morning hours. Conclusions Although the patients were normocalcemic, plasma PTH concentrations decreased with digoxin treatment. The effect of the sodium pump on PTH secretion might be important in human PTH homoeostasis and might be a potential target for the treatment of disturbances in calcium homoeostasis.

OBJECTIVE: To report the case of a patient with manic—depressive disorder who developed lithium intoxication following carbamazepine-induced acute renal failure. CASE SUMMARY: A 33-year-old white man with bipolar manic—depressive disorder was treated with lithium for the last 18 months. Three weeks prior to admission, carbamazepine 600 mg was added to the drug regimen due to a recurrence of the psychiatric disorder. He was admitted with signs of lithium intoxication. Acute renal failure due to carbamazepine-induced interstitial nephritis was diagnosed. DISCUSSION: The combination of carbamazepine and lithium is known to cause neurotoxicity. We describe a different interaction in which the toxic lithium concentrations were the result of carbamazepine-induced acute renal failure. CONCLUSIONS: When considering adding carbamazepine to lithium, careful follow-up of the patients is warranted to prevent this indirect drug interaction.

Background. The rare autosomal dominant genetic disorder familial hyperkalemia and hypertension which is caused by mutations in WNK4 kinase, is characterized by childhood hyperkalemia and hypercalciuria, and appearance of hypertension in the third to fourth decade. Accompanying short stature is often described. Methods. We determined height, blood pressure and blood and urinary biochemical parameters in members of a very large family of FHHt with the WNK4 Q565E mutation. Results. The family has 57 members, 30 of whom (including 14 children) are affected. Prehypertension occurred in 7/ 11 affected and 1/10 unaffected children (P = 0.024). Serum potassium (SK) was ~0.5 mmol/L higher in affected children vs adults [5.98 ± 0.42 vs 5.46 ± 0.40 mmol/L, respectively (P < 0.0001)] (33 samples from 11 children and 36 samples from eight adults). SK of ≥ 6.0 mmol/L occurred in 16/33 children's samples and in 3/36 adults' samples (P = 0.0003). Hyperkalaemia in children is currently untreated. Children also had more severe hyperchloraemia and hypercalciuria. The family contains four large subfamilies, and each includes 8-10 siblings. In one subfamily, height Z-score was lower in affected vs unaffected subjects [-2.69 ± 0.36 vs -1.05 ± 0.16, respectively (P < 0.0001)]. In the other three subfamilies, no such difference was found. Conclusions. Short stature is not part of FHHt with the WNK4 Q565E mutation. Children affected with FHHt have a high prevalence of prehypertension, and their hyperkalaemia is more severe than that of affected adults. Children may have a more severe defect in the basic mechanism that produces hyperkalaemia. We suggest that, in affected adults, the attenuation of hyperkalaemia and appearance of hypertension may be the result of a late rise in the activity of renal transporters or channels such as the epithelial sodium channel.

The selective serotonin reuptake inhibitors are major drugs used in psychiatry today. While serotonin syndrome has become more frequent in an overdose situation and when an interacting drug is given, the toxicity of SSIRs is less than that of most other psychiatric drugs. Although the characteristics of toxicity are defined, it seems that physicians are not aware of the phenomenon.To investigate patients with serotonin syndrome who were initially misdiagnosed.We conducted a retrospective chart review of seven patients admitted in the last 2 years with mild to severe serotonin syndrome who were initially diagnosed as having other diseases.Most patients (5/7) were initially diagnosed with exacerbation of their psychiatric disorder. Gastroenteritis was diagnosed in two patients. One patient was suspected of having a metastatic lesion in the brain, and severe drug overdose was diagnosed in one patient. They all recovered after withholding the culprit drugs.This report is an addition to the growing literature on misdiagnosis of psychiatric patients. Serotonin toxicity should be considered in patients in whom the combination of mental changes, neuromuscular abnormalities and autonomic hyperactivity are features of acute disease.

Cardiac conduction defects have not been previously described in association with hyponatremia, although in patients with congestive heart failure the frequency of ventricular premature beats was found to correlate to the severity of hyponatremia. We describe three patients with second-degree or complete atrioventricular (AV) block which occurred during or shortly after an episode of severe hyponatremia. The first had thiazide-induced hyponatremia while on amiodarone. In the second, definite etiology for hyponatremia which was associated with longstanding polydipsia could not be established. The third had ischemic heart disease and intermittent conversion of his first-degree to second-degree AV block while hyponatremic after diuretics use. Although it is usually difficult to single out hyponatremia as the cause of conduction defects which usually occur in the presence of cardiac disease, potent medications or other electrolyte abnormalities, we suggest that hyponatremia may play a role in the pathogenesis of conduction defects in the diseased heart.

Objective: To evaluate the pharmacokinetic parameters of morphine and lidocaine after a single intravenous dose in critically ill patients. Design: Prospective, clinical study. Setting: General intensive care unit (ICU) in a university hospital. Patients: Patients admitted to the ICU with severe systemic inflammatory response syndrome of various etiologies. Interventions: A single intravenous dose of morphine (0.025 mg/kg) and lidocaine (1.5 mg/kg) were given separately 12–36 h after admission, and arterial blood samples for serum drug levels were taken. Measurements and results: Morphine pharmacokinetics were studied in 30 patients. The clearance (Cl) was found to be 5.7 ± 2.3 ml/kg per min, volume of distribution of the central compartment (Vc) 0.16 ± 0.12 l/kg and volume of distribution at steady state (Vss) 1.08 ± 0.69 l/kg. These values are lower then those described previously for healthy volunteers (33.5 ± 9 ml/kg per min, 1.01 ± 0.31 l/kg, and 5.16 ± 1.4 l/kg, respectively), and similar to those described in trauma and burned patients. Lidocaine pharmacokinetics were tested in 24 subjects. The Cl was 6.9 ± 3.8 ml/kg per min, Vc 0.25 ± 0.1 l/kg and Vss 0.78 ± 0.26 l/kg. These values are not different from parameters published previously for healthy volunteers (10 ml/kg per min, 0.53 l/min and 1.32 l/min, respectively). No correlation was found between clinical variables and pharmacokinetic parameters of both drugs (ANOVA). Conclusions: Both morphine and lidocaine have a reduced volume of distribution in critically ill patients. The normal lidocaine clearance indicates preserved hepatic blood flow and suggests that other mechanisms are involved in the reduced morphine clearance. These findings may have application for the treatment of ICU patients.

WNK4 kinase mutations produce the autosomal dominant disorder familial hyperkalemia and hypertension (FHH), also known as pseudohypoaldosteronism type II, by a molecular mechanism that is not completely understood. In vitro experiments in frog oocytes showed that WNK4 affects ion transport systems such as the Na-Cl cotransporter and the renal outer medullary potassium channel. Some features of FHH suggest that long-term effects are involved in WNK4 signaling. In addition, WNK1 and WNK2, paralogs of WNK4, were shown to be involved in MAP kinase signaling. We therefore investigated possible WNK4 involvement in MAP kinase signaling. We stimulated HEK 293 cells overexpressing WNK4 by hypertonicity or using EGF, and measured phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 and p38. WNK4 augmented the phosphorylation of ERK1/2 and p38 in response to both hypertonicity and EGF. The FHH-producing and kinase-deficient mutants behaved similarly to wild-type WNK4. Hypertonicity stimulation was accompanied by cellular relocalization of WNK4 as manifested by its reversible disappearance from the supernatant fraction following extraction with a detergent-containing buffer. Live-cell microscopy showed that the cytoplasmic-soluble WNK4 redistributes rapidly to membrane-bound organelles, which, in the case of WNK1 kinase, were recently shown to represent trans-Golgi network/recycling endosomes. In contrast, EGF stimulation was not accompanied by redistribution of WNK4 as determined by cell fractionation or cell microscopy. The observation that WNK4-induced MAP kinase stimulation caused by hypertonicity, but not that caused by EGF, is associated with WNK4 subcellular redistribution suggests that this redistribution has a role in WNK4 signaling.

BACKGROUND: Familial hyperkalaemia and hypertension (FHH), also termed pseudohypoaldosteronism type II, is a rare monogenic form of hypertension caused by mutations in the WNK1 or WNK4 kinases. In vitro expression of WNK4 reduces surface abundance and activity of coexpressed NaCl cotransporter (NCCT). This effect is lost in disease-producing WNK4 mutants. In two mice models of FHH, one expressing two extra copies of mutant WNK4 (Q562E) and another in which a mutant (D561A) WNK4 replaced wild-type WNK4, renal distal tubule hyperplasia with overexpression of NCCT was found. Currently no FHH human renal tissue is available to test for increased distal tubule surface abundance of NCCT. The availability of a unique large family with FHH and the Q565E WNK4 mutation enabled us to investigate this issue in an indirect manner. METHODS: Assuming that shedding of NCCT to the urine reflects its abundance in the distal tubule epithelium, we measured urinary NCCT protein in eight subjects of the FHH family and in eight unrelated controls by western blotting. RESULTS: Urinary NCCT protein was about four times higher in FHH than in controls [111.1 +/- 40.5 versus 26.1 +/- 16.4 densitometry units (P < 0.0001)]. No significant difference in urinary sodium and potassium concentrations was seen between FHH and controls. CONCLUSIONS: The increased urinary NCCT in FHH most probably reflects increased NCCT abundance in the apical membrane of distal tubule cells in patients with FHH and the WNK4 mutation and points to the pathogenetic mechanism for the clinical phenotype of FHH and the WNK4 mutation, supporting results in transgenic mice with the same mutation and in knockin mice with another mutation.

Background Amiodarone is a very effective antiarrhytmic drug. However its use may be accompanied by side effects. Hyperglobulinemia was not described in association with amiodarone treatment. Materials and methods Fifteen patients, who developed hyperglobulinemia while on amiodarone therapy, were identified among the patients hospitalized in our hospital. Serum globulin concentration was measured prior to, during and after amiodarone therapy. Results In 11 of the 15 patients with amiodarone-associated hyperglobulinemia, amiodarone treatment had to be stopped because of amiodarone-induced complications, nine of them had pneumonitis. Mean serum globulin level rose during amiodarone therapy from 2.48±0.51 g/dL to 4.11±0.71 g/dL (p=0.001), and declined after it was stopped to 2.80±0.49 g/dL (p=0.001). In 50 patients treated by amiodarone, serum globulin was similar to that found in 50 patients with ischemic heart disease not treated by amiodarone [2.64±0.39 g/dL and 2.56±0.29 g/dL respectively (p=0.21)]. Conclusions In some patients amiodarone therapy may be associated with hyperglobulinemia. The incidence of this association is not known. Most of the patients with amiodarone-associated hyperglobulinemia have amiodarone-induced toxicity, mainly pneumonitis. Amiodarone therapy does not cause a general increase in serum globulins. Hyperglobulinemia may be a marker for a damaged organ, or it may have a pathogenetic role in the induction of pneumonitis.