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Ann R Falsey1,2, Kenneth L Becker3, Andrew J Swinburne2, Eric S Nylen3, Richard H Snider3, Maria A Formica2, Patricia A Hennessey2, Mary M Criddle2, Derick R Peterson4, Edward E Walsh1,21Department of Medicine, University of Rochester, 2Rochester General Hospital, Rochester, NY, 3Veterans Affairs Medical Center and George Washington University, Washington DC, 4Biostatistics and Computational Biology, University of Rochester, Rochester, NY, USABackground: Serum procalcitonin levels have been used as a biomarker of invasive bacterial infection and recently have been advocated to guide antibiotic therapy in patients with chronic obstructive pulmonary disease (COPD). However, rigorous studies correlating procalcitonin levels with microbiologic data are lacking. Acute exacerbations of COPD (AECOPD) have been linked to viral and bacterial infection as well as noninfectious causes. Therefore, we evaluated procalcitonin as a predictor of viral versus bacterial infection in patients hospitalized with AECOPD with and without evidence of pneumonia.Methods: Adults hospitalized during the winter with symptoms consistent with AECOPD underwent extensive testing for viral, bacterial, and atypical pathogens. Serum procalcitonin levels were measured on day 1 (admission), day 2, and at one month. Clinical and laboratory features of subjects with viral and bacterial diagnoses were compared.Results: In total, 224 subjects with COPD were admitted for 240 respiratory illnesses. Of these, 56 had pneumonia and 184 had AECOPD alone. A microbiologic diagnosis was made in 76 (56%) of 134 illnesses with reliable bacteriology (26 viral infection, 29 bacterial infection, and 21 mixed viral bacterial infection). Mean procalcitonin levels were significantly higher in patients with pneumonia compared with AECOPD. However, discrimination between viral and bacterial infection using a 0.25 ng/mL threshold for bacterial infection in patients with AECOPD was poor.Conclusion: Procalcitonin is useful in COPD patients for alerting clinicians to invasive bacterial infections such as pneumonia but it does not distinguish bacterial from viral and noninfectious causes of AECOPD.Keywords: virus, bacterial infection, procalcitonin, chronic obstructive pulmonary disease, bronchitis

A peripheral (gingival) fibroma, a gingival cyst and hyperplastic gingivitis occurred simultaneously in a man with metastatic medullary thyroid carcinoma (MCT). The gingival growths and hyperplasia appeared to be related to poor oral hygiene rather than to the MTC. Despite the patient's improved oral hygiene, the hyperplastic gingivitis and peripheral fibroma recurred, and a new peripheral fibroma and gingival cyst developed, which prompted reconsideration of a link with the MTC. MTC cells secrete calcitonin (CT), procalcitonin (ProCT) and growth factors; the patient's serum CT and ProCT were several fold higher than normal. The patient's salivary CT and ProCT also were elevated, but α-amylase and epidermal growth factor (EGF) were not, compared to three healthy controls. A possible link between the MTC and gingival hyper-reactivity due to CT and/or ProCT promoting inflammatory cytokines, and the utility of salivary ProCT as an indicator of periodontitis in this patient were explored further. Unstimulated whole saliva and serum were collected from the patient followed by a standard periodontal examination before periodontal treatment, and 3 weeks and 3 months after treatment. This cycle was repeated 7 months after the previous periodontal treatment. The saliva was assayed for ProCT and the serum was assayed for ProCT, high sensitivity C-reactive protein (CRP), interleukin-6 (IL-6) and proadrenomedullin (ProADM). The results were analyzed for correlations among the severity of periodontitis and the biomarkers/cytokines. Only the salivary ProCT was correlated with the severity of periodontitis, i.e. it was higher just before and lower at 3 weeks and 3 months after each periodontal treatment. The patient's salivary ProCT content also was much higher than reported elsewhere. The other biomarkers/cytokines were within normal ranges. Our findings indicate that salivary ProCT is independent of serum ProCT and therefore may be a useful marker for moderate to severe periodontitis in patients with MTC. The greatly elevated salivary and serum CT and ProCT, and a trend toward correlation between the serum CRP and ProCT suggest a pro-inflammatory link between the MTC and the hyperreactive gingiva in this patient. Further studies are warranted to determine whether hyperplastic gingivitis and gingival growths, such as cysts and fibromas, occur with unusual frequency in patients with MTC.

Context: Statins are commonly prescribed to avert cardiovascular disease in diabetics. Little information, however, exists about the interrelationship of obesity, fitness, and statin treatment on mortality., Objective: Our objective was to evaluate the influence of statin therapy on body mass index (BMI), cardiorespiratory fitness, and all-cause mortality risk in diabetics., Design: We gathered prospective observational data from Veterans Affairs Medical Centers in Washington, DC, and Palo Alto, California, on type 2 diabetic male veterans (n = 3775; mean age = 58.9 ± 9.9 years) who underwent an exercise tolerance test during the period of 1986 to 2011., Results: There were 930 deaths during a mean follow-up period of 10.5 years (37 826 person-years), with an average annual mortality of 24.6 events per 1000 person-years of observation. Adjusted Cox proportional hazard analysis revealed that mortality risk was 34% lower (hazard ratio [HR] = 0.66; confidence interval [CI] = 0.57-0.77) for individuals treated with statins compared with those not on statins. There was a paradoxical BMI-mortality association, with the highest mortality in those with a BMI of 18.5 to 24.9 kg/m(2) (HR = 1.54; CI = 1.26-1.87, P < .0001) compared with obese subjects (BMI of 30-34.9 kg/m(2)). However, this paradoxical association was evident only in those not treated with statins (HR = 1.79; CI = 1.39-2.29; P < .001) vs those on statins (HR = 1.06; CI = 0.75-1.54; P = .70). When statin therapy and fitness status were combined, mortality risk was 44% higher (HR = 1.44; CI = 1.16-1.78) in the least-fit not treated with statins compared with the least-fit treated with statins. Mortality risk declined progressively with increased fitness to 60% lower (HR = 0.40; CI = 0.24-0.66) and 49% lower (HR = 0.51; CI = 0.38-0.68) for the most highly fit individuals (>9 metabolic equivalents) treated and not treated with statins, respectively., Conclusion: Statin therapy was associated with increased survival in diabetic veterans, which was further enhanced when fitness and statin therapy were combined. In addition, statin therapy eliminated the increased mortality risk associated with BMI <25 kg/m(2). The presence of a paradoxical BMI-mortality risk association, which is modulated by statin therapy has novel clinically relevant implications.

Objectives: This study investigated the effects of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) on gut barrier function in critically ill surgical patients., Methods: A prospective observational cohort study on patients with severe acute pancreatitis or abdominal sepsis admitted to an intensive care or high-dependency unit. Intra-abdominal pressure (IAP) and plasma levels of immunoglobulin G (IgG) and IgM antiendotoxin core antibodies (EndoCAb) and procalcitonin (ProCT) were measured serially., Results: Among 32 recruited patients, 24 (75%) and 8 patients (25%) developed IAH and ACS, respectively. The state of ACS was associated with significant reductions in plasma IgG EndoCAb (P = 0.015) and IgM EndoCAb (P = 0.016) and higher concentrations of plasma ProCT (P = 0.056) compared with absence of ACS. Resolution of IAH and ACS was associated with significant recovery of plasma IgG EndoCAb (P = 0.003 and P = 0.009, respectively) and IgM EndoCAb (P = 0.002 and P = 0.003, respectively) and reduction in plasma ProCT concentration (P = 0.049 and P = 0.019, respectively). Negative correlations were observed between IAP and plasma IgG EndoCAb (P = 0.003) and IgM EndoCAb (P = 0.002)., Conclusions: Intra-abdominal hypertension and ACS are associated with significantly higher endotoxin exposure and ProCT concentrations, suggestive of gut barrier dysfunction. Resolution of IAH and ACS is associated with evidence for recovery of gut barrier function.

The cellular processes that unfold in critical illness involve a variety of circulating substances, that may provide clinically relevant insight into the severity and outcome. Among hormonal markers, cortisol, several thyroid-related substances, as well as natriuretic peptides are discussed in this review. Glucose and lipids constitute metabolic markers, the identification and treatment of the former has been of particular importance. Among immune markers, both proinflammatory and anti-inflammatory cytokines, such as interleukin-6, contribute essential prognostic information. Finally, the complement and coagulation pathways also provide unique insight into this complex and heterogeneous process.

Background: Severe acute pancreatitis is associated with an early increase in intestinal permeability and endotoxemia. Endotoxin is a potent stimulator for the production and release of procalcitonin and its components (calcitonin precursors; [CTpr]). The aim of this study is to evaluate the role of plasma CTpr as an early marker for gut barrier dysfunction in patients with acute pancreatitis., Methods: Intestinal permeability to macromolecules (polyethylene glycol 3350), serum endotoxin and antiendotoxin core antibodies, plasma CTpr, and serum C-reactive protein (CRP) were measured on admission in 60 patients with acute pancreatitis. Attacks were classified as mild (n = 48) or severe (n = 12) according to the Atlanta criteria., Results: Compared with mild attacks of acute pancreatitis, severe attacks were significantly associated with an increase in intestinal permeability index (median: 0.02 vs. 0.006, P < 0.001), the frequency of endotoxemia (73% vs. 41%, P = 0.04), and the extent of depletion of serum IgM antiendotoxin antibodies (median: 43 MMU vs. 100 MMU, P = 0.004). Plasma CTpr levels were significantly elevated in patients with severe attacks compared with mild attacks on both the day of admission and on day 3 (median: 64 vs. 22 fmol/mL, P = 0.03; and 90 vs. 29 fmol/mL, P = 0.003 respectively). A positive and significant correlation was observed between the admission serum endotoxin and plasma CTpr levels on admission (r = 0.7, P < 0.0001) and on day 3 (r = 0.96, P < 0.0001), and between plasma CTpr on day 7 and the intestinal permeability index (r = 0.85, P = 0.0001). In contrast, only a weak positive correlation was observed between peak serum levels of CRP and plasma CTpr on admission (r = 0.3, P = 0.017) and on day 7 (r = 0.471, P = 0.049), as well as between CRP and each of the admission serum endotoxin (r = 0.3, P = 0.03) and the intestinal permeability index (r = 0.375, P = 0.007)., Conclusions: In patients with acute pancreatitis, plasma concentrations of CTpr appear to reflect more closely the derangement in gut barrier function rather than the extent of systemic inflammation.

Background: Calcitonin precursors are sensitive markers of inflammation and infection. The aim of this study was to evaluate the role of plasma calcitonin precursor levels on the day of admission in the prediction of severity of acute pancreatitis, and to compare this with the Acute Physiology And Chronic Health Evaluation (APACHE) II scoring system., Methods: Plasma concentrations of calcitonin precursors were determined on admission in 69 patients with acute pancreatitis. APACHE II scores were calculated on admission. Attacks were classified as mild (n = 55) or severe (n = 14) according to the Atlanta criteria. Plasma calcitonin precursor levels were determined with a sensitive radioimmunoassay., Results: On the day of hospital admission, plasma levels of calcitonin precursors were significantly greater in patients with a severe attack compared with levels in those with a mild attack of pancreatitis (median 64 versus 25 fmol/ml; P = 0.014), but the APACHE II scores were no different (median 9 versus 8; P = 0.2). The sensitivity, specificity, positive predictive and negative predictive values, and accuracy for the prediction of severe acute pancreatitis were 67, 89, 57, 93 and 85 per cent respectively for plasma calcitonin precursor levels higher than 48 fmol/ml, and 69, 45, 23, 86 and 50 per cent respectively for an APACHE II score greater than 7. Differences in the specificity and accuracy of the two prognostic indicators were significant (P < 0.001 and P = 0.001 respectively). A plasma calcitonin precursor concentration of more than 160 fmol/ml on admission was highly accurate (94 per cent) in predicting the development of septic complications and death., Conclusion: The assay of plasma calcitonin precursors on the day of admission to hospital has the potential to provide a more accurate prediction of the severity of acute pancreatitis than the APACHE II scoring system.

Prior studies have demonstrated that the prohormone, procalcitonin (ProCT), and its component calcitonin precursors (CTpr) are increased in the serum of septic patients, correlate with the severity of the illness, and persist for relatively long periods of time. Animal studies in septic hamsters have revealed that the administration of ProCT is toxic and that immunoneutralization with IgG that is reactive to this molecule significantly improves survival. A large animal model of a very rapidly lethal polymicrobial sepsis has been developed in the pig in order to measure continuous physiological and metabolic parameters and also to compare the effects in this animal of an immunoneutralization, which is performed late in the course of the disease, to an identical, but early, therapy. Based upon the physiological and metabolic parameters, the late therapy, which was initiated during the fourth hour at a time when pigs were nearly moribund, was found to be as beneficial as early therapy. In both late and early therapy, the only animals to survive at the predetermined time of euthanasia were those which had received immunoneutralization therapy.

Objective: The 116 amino acid prohormone procalcitonin and some of its component peptides (collectively termed calcitonin precursors) are important markers and mediators of sepsis. In this study, we sought to evaluate the effect of immunoneutralization of calcitonin precursors on metabolic and physiologic variables of sepsis in a porcine model., Design: A prospective, controlled animal study., Setting: A university research laboratory., Subjects: 30-kg Yorkshire pigs., Interventions: Sepsis was induced in 15 pigs by intraperitoneal instillation of a suspension of cecal content (1 g/kg animal body weight) and a toxinogenic Escherichia coli solution (2 x 10(11) colony-forming units). During induction of sepsis, seven pigs received an intravenous infusion of purified rabbit antiserum, reactive to the aminoterminal portion of porcine prohormone procalcitonin. Another eight control pigs received an intravenous infusion of purified nonreactive rabbit antiserum. For all 15 animals, physiologic data (urine output, core temperature, arterial pressure, heart rate, cardiac index, and stroke volume index) and metabolic data (serum blood urea nitrogen and creatinine, arterial lactate, and pH) were collected or recorded hourly until death at 15 hrs., Measurements and Main Results: In this large-animal model of rapidly lethal peritonitis, serum calcitonin precursors were significantly elevated. Amino-prohormone procalcitonin-reactive antiserum administration resulted in a significant improvement or a beneficial trend in a majority of the measured physiologic and metabolic derangements induced by sepsis. Specifically, arterial pressure, cardiac index, stroke volume index, pH, and creatinine were all significantly improved, while urine output and serum lactate had beneficial trends. Treated animals also experienced a statistically significant increase of short-term survival., Conclusions: These data from a large-animal model with polymicrobial sepsis demonstrate the salutary effect of early immunoneutralization of calcitonin precursors on physiologic and metabolic variables. Immunologic blockade of calcitonin precursors may offer a novel therapeutic approach to human sepsis.

Despite the considerable advances made in understanding the pathophysiology of systemic inflammation during critical illness, clinical progress has been elusive as it remains a very deadly condition. Cortisol and thyroid hormone levels can be as predictive of outcome as the commonly used severity parameters (i.e. APACHE). Indeed, levels of endocrine humoral substances such as arachidonic acids, nitric oxide, endothelin, calcitonin precursors, leptin and adenosine correlate with the severity and outcome of critical illness. Furthermore, calcitonin precursors represent a potentially new hormokine paradigm, being transcriptionally activated in all cells in response to infection. The cytokines are immune markers that often correlate with severity and outcome, but their release is transient. In contrast, the so-called acute phase proteins, such as C-reactive protein and serum amyloid A, are highly sensitive to inflammatory activity and can be important markers of severity and outcome. Leukocyte esterase, adhesion molecules, platelet activating factor and activated protein C are additional humoral immune markers; the replacement of the latter has been shown to be a promising therapeutic option. Natriuretic peptides are neurocrine humoral markers that have important cardiovascular implications. The level of macrophage migrating inhibitory factor, released by the pituitary, is elevated in sepsis and counteracts glucocorticoid action. Cellular markers to severe stress include the enhanced expression of protective substances in the form of heat shock proteins. High mobility group-1 is a DNA-binding protein and a late mediator of the inflammatory response. Apoptotic markers such as the soluble fas ligand are also elevated in inflammation. In summary, during critical illness, the endocrine, immune and nervous systems elaborate a multitude of humoral markers, the roles of which merit further scrutiny in order to improve therapeutic outcome., (Copyright 2001 Harcourt Publishers Ltd.)

Calcitonin precursors (CTpr), including procalcitonin, are important markers and also potentially harmful mediators in response to microbial infections. The source and function of CTpr production in sepsis, however, remains an enigma. In the classical view, the transcription of the CT-I gene is restricted to neuroendocrine cells, in particular the C cells of the thyroid. To better understand the pathophysiology of CTpr induction in sepsis, we used an animal model analog to human sepsis, in which bacterial infection is induced in hamsters by implanting Escherichia coli pellets ip. Compared with control hamsters, levels of CTpr were elevated several fold in septic plasma and in nearly all septic hamster tissues analyzed. Unexpectedly, CT-messenger RNA was ubiquitously and uniformly expressed in multiple tissues throughout the body in response to sepsis. Notably, the transcriptional expression of CT-messenger RNA seemed more widely up-regulated in sepsis than were classical cytokines (e.g. tumor necrosis factor-alpha and interleukin-6). Our findings, which describe a potentially new mechanism of host response to a microbial infection mediated by CTpr, introduce a new pathophysiological role for the CT-I gene.

Objective: Procalcitonin, the precursor peptide of calcitonin, has been shown to be a serum marker of the severity and mortality of several systemic inflammatory response syndromes. This study addressed the correlation of serum procalcitonin with the course of classic (nonexertional) heatstroke., Design: Serum samples were collected prospectively every 6 hrs for 24 hrs., Setting: Heatstroke treatment unit, Makkah, Saudi Arabia., Patients: A total of 25 patients were admitted during the annual Hajj pilgrimage in 1994. Ten patients evaluated in the same treatment center with minor illnesses and without pyrexia served as controls., Interventions: Patients were cooled according to an established evaporation method., Measurements and Main Results: Standard critical care parameters including continuous rectal temperature. A rapid immunochemical assay for serum procalcitonin was utilized. The mean serum procalcitonin was elevated 20-fold on admission in patients with heatstroke compared with controls (p < .011). The procalcitonin concentration subsequently increased to a plateau by 6 hrs and remained increased at 24 hrs, compared with the admission level (p < .0001). In this study, 77% of the patients with heatstroke survived. A subgroup analysis demonstrated that the patients who survived had a significantly higher procalcitonin concentration than those patients who died of heatstroke; a procalcitonin concentration of >0.5 ng/mL (>0.15 nmol/L) at 6 hrs predicted survival (p = .02)., Conclusion: Classic heatstroke is associated with increased concentrations of serum procalcitonin, particularly among survivors. Further studies are required to elucidate the source and action(s) of procalcitonin as well as its relationship to cytokine activation.

Growth hormone (GH) has been in clinical use for almost 40 years to promote linear growth in growth hormone deficient children. Treatment has usually been stopped after the epiphyseal plates have fused or when the person reaches a proper height. Previously, GH replacement therapy in adults was not deemed clinically indicated. GH-deficiency in adults is now accepted as a clinical entity, manifested by cardiovascular dysfunction, dyslipidemia, reduced capacity for exercise and muscular weakness, altered body composition, increased prevalence of osteoporosis, and impaired psychological well-being. The treatment of adults used to be unrealistic, because of the limited supply of human pituitary-derived GH. Moreover, the risk of transferring Creutzfeldt-Jakobs disease led to a stop in the therapeutic use of pituitary GH preparations. The availability of recombinant human prion-free GH has made replacement therapy possible in GH-deficient adults. In this review, the GH deficiency syndrome in adults is described, together with the results of recent clinical studies of GH replacement treatment in adults.

Elevated serum levels of the prohormone of calcitonin (CT), procalcitonin (ProCT), have been documented in illnesses such as inhalational burn injury, in several sepsis syndromes, and in endotoxemia. In this study, we measured and characterized the circulating precursor forms of CT during the course of infectious pneumonitis. The initial (mean +/- SEM) serum total multiform CT level in 12 patients with acute infectious pneumonia was 1,019 +/- 430 pg/mL. In comparison, the mean level of total CT for 19 age-matched control patients without lung disease was 32 +/- 6 pg/mL (P < 0.001). The mean serum total CT level on initial examination was greater in the 6 patients with bacterial isolates, at 1,793 +/- 752 pg/mL, than in those with nonbacterial infectious pneumonia, at 242 +/- 109 pg/mL (P = 0.018). After admission to the hospital, patients' serum total CT progressively declined concomitantly with the clinical resolution of the pneumonia; at discharge, mean serum level was 121 +/- 34 pg/mL. On discharge, the patients who had persistent radiographic abnormalities had significantly higher levels than did those who had complete resolution. Both the mean serum calcium and phosphate were significantly lower at the initial time of study than at discharge (P < 0.002 and P < 0.0004, respectively). Gel filtration chromatography of sera obtained during the acute pneumonitis phase revealed increased levels of precursor forms of CT, including ProCT; these levels diminished with clinical resolution. In an additional three patients, the serum total CT increased very rapidly after aspiration (within 6 to 12 hours); the peak levels were several times greater than the upper limits of normal. In these patients, the principal serum CT components were ProCT and other precursor forms. These results show that both infectious and aspiration pneumonitis are associated with a rapid increase in circulating ProCT and other precursor forms of CT.

Slices of the molecular layer of the dentate gyrus of the hippocampal formation were incubated with either [14C]glucose, [14C]pyruvate or 14C glutamine and the efflux of endogenous and radioactive glutamate was monitored under various conditions. After prelabeling with either [14C]glutamine or [14C]glucose elevation of K+ concentration to 56 mM (Ca2+ free) increased efflux of endogenous and [14C]glutamate. Introduction of Ca2+ into the elevated K+ medium further increased the efflux of endogenous glutamate and radioactive glutamate derived from any of the precursors tested. In glutamine containing media, the increase in glutamate efflux as well as basal efflux was considerably higher than in the absence of glutamine and the specific activity of glutamate release was higher than that in tissue. Thus glutamine was superior to glucose or pyruvate as precursor and most specifically labeled the putative transmitter pool of glutamate. Similar experiments were carried out 4 and 14 days after a unilateral lesion in the entorhinal cortex which provides about 60% of the total synaptic input to the dentate granule cells. The Ca2+ dependent release of glutamate derived from either glucose or glutamine was markedly reduced on the operated side. This result suggests that the transmitter pool of glutamate is in perforant path terminals and can be synthesized from glucose or glutamine.