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Electronic ICUs (eICUs) have arisen as an effort to improve the intensive care medical coverage still unavailable to many patients. The overriding issue is the ongoing shortage of critical care medicine physicians and an ever-growing population of critical care patients. However, it has been difficult to conclusively define the outcome benefits in terms of mortality or ICU length of stay following establishment of an eICU program. Successful outcomes have been demonstrated in ICU settings ranging from academic to rural, but eICUs may have the most impact in ICUs that ( a) begin with a deficit ofintensivist coverage, ( b) have high severity-adjusted mortality and long length of stay rates, ( c) are located remotely where safe transfer of high acuity patients is not possible, and ( d) are part of an organizational structure that support the tele-ICU intensivist’s management of the patient. Acceptance of telepresence technology and particularly the acceptance of a remote intensivist managing patients can encounter strong resistance by many bedside clinicians. Third-party payers have traditionally not paid for intensivists to provide patient care via real-time telemedicine systems. There may also be vulnerability to liability to all those involved in ICU care if communication between bedside and eICU practitioners break down. This review describes the various components of an eICU program and discuss the barriers we encountered in developing an eICU program in a large, multihospital health care system.

Analysis of whether assiduous implementation of American Thoracic Society/Centers for Disease Control and Prevention/Infectious Diseases Society of America guidelines for targeted testing and treatment of latent tuberculosis infection could have prevented any of 223 cases of active tuberculosis in foreign-born persons in San Francisco during the period 2002-2003. We report that 62% of these cases were not preventable and conclude that a further reduction in the incidence of tuberculosis among foreign-born persons will be modest without modification of current guidelines.

Drug-induced liver injury (DILI) is a problem of increasing significance, but has been a long-standing concern in the treatment of tuberculosis (TB) infection. The liver has a central role in drug metabolism and detoxification, and is consequently vulnerable to injury. The pathogenesis and types of DILI are presented, ranging from hepatic adaptation to hepatocellular injury. Knowledge of the metabolism of anti-TB medications and of the mechanisms of TB DILI is incomplete. Understanding of TB DILI has been hampered by differences in study populations, definitions of hepatotoxicity, and monitoring and reporting practices. Available data regarding the incidence and severity of TB DILI overall, in selected demographic groups, and in those coinfected with HIV or hepatitis B or C virus are presented. Systematic steps for prevention and management of TB DILI are recommended. These include patient and regimen selection to optimize benefits over risks, effective staff and patient education, ready access to care for patients, good communication among providers, and judicious use of clinical and biochemical monitoring. During treatment of latent TB infection (LTBI) alanine aminotransferase (ALT) monitoring is recommended for those who chronically consume alcohol, take concomitant hepatotoxic drugs, have viral hepatitis or other preexisting liver disease or abnormal baseline ALT, have experienced prior isoniazid hepatitis, are pregnant or are within 3 months postpartum. During treatment of TB disease, in addition to these individuals, patients with HIV infection should have ALT monitoring. Some experts recommend biochemical monitoring for those older than 35 years. Treatment should be interrupted and, generally, a modified or alternative regimen used for those with ALT elevation more than three times the upper limit of normal (ULN) in the presence of hepatitis symptoms and/or jaundice, or five times the ULN in the absence of symptoms. Priorities for future studies to develop safer treatments for LTBI and for TB disease are presented.

OBJECTIVE To assess the impact of implementing a low tidal volume ventilation strategy on hospital mortality for patients with acute lung injury or acute respiratory distress syndrome. DESIGN Retrospective, uncontrolled study. SETTING Adult medical-surgical and trauma intensive care units at a major inner city, university-affiliated hospital. PATIENTS A total of 292 patients with acute lung injury or acute respiratory distress syndrome. INTERVENTIONS Between the years 2000 and 2003, 200 prospectively identified patients with acute lung injury/acute respiratory distress syndrome were managed by the ARDS Network low tidal volume protocol. A historical control group of 92 acute respiratory distress syndrome patients managed by routine practice from 1998 to 1999 was used for comparison. MEASUREMENTS AND MAIN RESULTS Patients managed with the ARDS Network protocol had a lower hospital mortality compared with historical controls (32% vs. 51%, respectively; p = .004). Multivariate logistic regression estimated an odds ratio of 0.32 (95% CI, 0.17-0.59; p = .0003) for mortality risk with use of the ARDS Network protocol. Protocol-managed patients had a lower tidal volume (6.2 +/- 1.1 vs. 9.8 +/- 1.5 mL/kg; p < .0001) and plateau pressure (27.5 +/- 6.4 vs. 33.8 +/- 8.9 cm H2O; p < .0001) than historical controls. CONCLUSION Adoption of the ARDS Network protocol for routine ventilator management of acute lung injury/acute respiratory distress syndrome patients was associated with a lower mortality compared with recent historical controls.

Background : Recently, a short-course treatment using 60 daily doses of rifampin and pyrazinamide was recommended for latent tuberculosis (TB) infection (LTBI) Study objectives : To determine the acceptability, tolerability, and completion of treatment Design : Observational cohort study Setting : Five county jails and TB outreach clinics for homeless populations in three cities Patients : Study staff enrolled 1,211 patients (844 inmates and 367 homeless persons) Interventions : Sites used 60 daily doses of rifampin and pyrazinamide, an approved treatment regimen for LTBI Measurements : Types and frequency of drug-related adverse events and outcomes of treatment Results : Prior to treatment, 25 of 1,178 patients (2.1%) had a serum aminotransferase measurement at least 2.5 times the upper limit of normal. Patients who reported excess alcohol use in the past 12 months were more likely than other patients to have an elevated pretreatment serum aminotransferase level (odds ratio, 2.1; 95% confidence interval, 1.1 to 6.1; p = 0.03). Treatment was stopped in 66 of 162 patients (13.4%) who had a drug-related adverse event. Among 715 patients who had serum aminotransferase measured during treatment, 43 patients (6.0%) had an elevation > 5 times the upper limits of normal, including one patient who died of liver failure attributed to treatment. In multivariate analyses, increasing age, an abnormal baseline aspartate aminotransferase level, and unemployment within the past 24 months were independent risk factors for hepatotoxicity. Completion rates were similar in jail inmates (47.5%) and homeless persons (43.6%) Conclusions : This study detected the first treatment-associated fatality with the rifampin and pyrazinamide regimen, prompting surveillance that detected unacceptable levels of hepatotoxicity and retraction of recommendations for its routine use. Completion rates for LTBI treatment using a short-course regimen exceeds historical rates using isoniazid. Efforts to identify an effective short-course treatment for LTBI should be given a high priority

Effective treatment of tuberculosis requires adherence to a minimum of 6 months treatment with multiple drugs. To improve adherence and cure rates, directly observed therapy is recommended for the treatment of pulmonary tuberculosis. We compared treatment outcomes among all culture-positive patients treated for active pulmonary tuberculosis (n = 372) in San Francisco County, California from 1998 through 2000. Patients treated by directly observed therapy at the start of therapy (n = 149) had a significantly higher cure rate compared with patients treated by self-administered therapy (n = 223) (the sum of bacteriologic cure and completion of treatment, 97.8% versus 88.6%, p < 0.002), and decreased tuberculosis-related mortality (0% vs. 5.5%, p = 0.002). Rates of treatment failure, relapse, and acquired drug resistance were similar between the two groups. Forty-four percent of patients who received self-administered therapy had risk factors for nonadherence and should have been assigned to directly observed therapy. We conclude that treatment plans that emphasize directly observed therapy from the start of therapy have the greatest success in improving tuberculosis treatment outcomes.

Two months of treatment with rifampin-pyrazinamide (RZ) and 9 months of treatment with isoniazid are both recommended for treatment of latent tuberculosis infection in adults without human immunodeficiency virus infection, but the relative cost-effectiveness of these 2 treatments is unknown. We used a Markov model to conduct a cost-effectiveness analysis to assess the impact on life expectancy and costs based on the results of a recent clinical trial that compared the rates of adverse events and completion of the 2 treatment regimens. Compared with no treatment, both regimens increased life expectancy by 1.2 years, but RZ cost 273 dollars more per patient. Sensitivity analyses showed that, assuming equal efficacy between the 2 regimens, there was no threshold completion rate for RZ at which the 2 treatments would be of equal net cost. Under most circumstances, treatment of latent tuberculosis infection with isoniazid is cost-saving than treatment with RZ.

A 44-year-old man who recently immigrated from Peru is found to have induration of 16 mm on a tuberculin skin test. He received bacille Calmette–Guerin vaccine as an infant and is asymptomatic. Chest radiography shows fibronodular opacities in the upper lobe. In another case, a 27-year-old schoolteacher born in the United States has induration of 17 mm on a tuberculin skin test, no symptoms, and a normal chest radiograph. How should these patients' cases be managed?

Isoniazid taken daily for 12 mo and isoniazid and rifampin taken daily for 4 mo are both recommended options for patients with radiographic evidence of previous tuberculosis and positive tuberculin skin tests who have not had prior treatment. We compared the completion rates, number of adverse effects, and cost effectiveness of these two regimens. Patients were treated at the San Francisco Tuberculosis Clinic from 1993 through 1996. A Markov model was developed to assess impact on life expectancy and costs. One thousand twenty-two patients, with a mean age of 52 yr, and > 90% foreign born, were treated; 545 received isoniazid and 477 received isoniazid and rifampin. For isoniazid, 79.8% completed 12 mo of therapy and 4.9% had adverse effects versus 83.6% completion, 6.1% adverse effects for isoniazid and rifampin (p > 0.05 for all between-group comparisons). Both regimens increased life expectancy by 1.4-1.5 yr. Compared with isoniazid, isoniazid and rifampin produced net incremental savings of $135 per patient treated. In patients with radiographic evidence of prior tuberculosis who have not been previously treated, isoniazid for 12 mo and isoniazid and rifampin for 4 mo have similar rates of completion and adverse effects, and both increase life expectancy compared with no treatment. Isoniazid and rifampin for 4 mo is cost saving compared with isoniazid alone. This advantage was maintained even when compared with 9 mo of isoniazid, the new American Thoracic Society/Centers for Disease Control (ATS/CDC) recommendation for treatment with isoniazid alone.

Noninvasive ventilation refers to any form of ventilatory support applied without the use of an endotracheal tube. It offers the potential to provide primary treatment for acute respiratory failure while avoiding complications associated with mechanical ventilation with endotracheal intubation. Noninvasive ventilation has been most commonly studied in hypercapnic respiratory failure. A review of randomized, controlled studies shows mixed results and methodologic limitations affect the interpretation of current evidence. Patient selection is clearly the most important issue in considering noninvasive ventilation for acute respiratory failure. Unfortunately, patients who benefit from noninvasive ventilation represent only a minority of the total group with any one disease, and thus it is difficult to make broad conclusions concerning applicability of this treatment modality. Future studies are needed to focus on determining the specific patient populations who will benefit the most, evaluating the optimal ventilatory mode and mask for providing noninvasive ventilation, and clarifying its impact on clinical outcomes.

To determine the factors contributing to tuberculosis incidence in the U.S.-born and foreign-born populations in San Francisco, California, and to assess the effectiveness of tuberculosis control efforts in these populations, we performed a population-based molecular epidemiologic study using 367 patients with strains of Mycobacterium tuberculosis recently introduced into the city. IS6110-based and PGRS-based restriction fragment length polymorphism (RFLP) analyses were performed on M. tuberculosis isolates. Patients whose isolates had identical RFLP patterns were considered a cluster. Review of public health and medical records, plus patient interviews, were used to determine the likelihood of transmission between clustered patients. None of the 252 foreign-born cases was recently infected (within 2 yr) in the city. Nineteen (17%) of 115 U. S.-born cases occurred after recent infection in the city; only two were infected by a foreign-born patient. Disease from recent infection in the city involved either a source or a secondary case with human immunodeficiency virus (HIV) infection, homelessness, or drug abuse. Failure to identify contacts accounted for the majority of secondary cases. In San Francisco, disease from recent transmission of M. tuberculosis has been virtually eliminated from the foreign-born but not from the U.S.-born population. An intensification of contact tracing and screening activities among HIV-infected, homeless, and drug-abusing persons is needed to further control tuberculosis in the U.S.-born population. Elimination of tuberculosis in both the foreign-born and the U.S. -born populations will require widespread use of preventive therapy.

We report a complicated case of acute respiratory distress syndrome (ARDS) from severe sepsis, in which we measured the ratio of physiologic dead space to tidal volume (V(D)/V(T)) with volumetric capnography prior to, during, and after therapy with human recombinant activated protein C. Previous studies hypothesized that early in ARDS, elevated V(D)/V(T) primarily reflects increased alveolar V(D), probably caused by pronounced thrombi formation in the pulmonary microvasculature. This may be particularly true when severe sepsis is the cause of ARDS. We repeatedly measured V(D)/V(T) in a 29-year-old man with sepsis-induced ARDS over the course of activated protein C therapy. Treatment with activated protein C resulted in a pronounced reduction in V(D)/V(T), from 0.55 to 0.27. Alveolar V(D) decreased from 165 mL to 11 mL (93% reduction). Activated protein C was terminated at 41 h because of gastrointestinal bleeding. When the measurement was repeated 29 h after therapy was discontinued, V(D)/V(T) had increased modestly, to 0.34, whereas alveolar V(D) had increased to 71 mL, or 43% of the pre-activated-protein-C baseline measurement. Alveolar V(T) rose from 260 mL to 369 mL and decreased slightly after termination of activated protein C (336 mL). Over the course of activated protein C therapy there was a persistent decrease in alveolar V(D) and increase in alveolar V(T), even while positive end-expiratory pressure was reduced and respiratory-system compliance decreased. Thus, improved alveolar perfusion persisted despite signs of alveolar de-recruitment. This suggests that activated protein C may have reduced microvascular obstruction. This report provides indirect evidence that microvascular obstruction may play an important role in elevated V(D)/V(T) in early ARDS caused by severe sepsis.

Tuberculosis (TB) has emerged as a global public health epidemic. Despite decreasing numbers of cases in the United States since 1992, TB remains a serious public health problem among certain patient populations and is highly prevalent in many urban areas. The responsibility for prescribing an appropriate drug regimen and ensuring that treatment is completed is assigned to the public health program or the clinician not to the patient. The initial prescribed regimen for the treatment of TB usually consists of 4 drugs: isoniazid, rifampin, pyrazinamide, and ethambutol. The minimum length for the treatment of drug-susceptible TB with a rifampin-based regimen is 6 to 9 months. Providing medications directly to the patient and watching him/her swallow the anti-TB drugs, which is termed directly observed therapy, is recommended for all patients diagnosed with TB and can help ensure higher completion rates, prevent the emergence of drug resistant TB, and enhance TB control. There has been renewed interest in the treatment of those with latent TB infection as a TB-control strategy in the United States for eliminating the large reservoir of individuals at risk for progression to TB. The 2 broad categories of persons who should be tested for latent TB infection are those who are likely to have been recently infected (such as contacts to infectious TB cases) and persons who are at increased risk of progression to TB disease following infection with Mycobacterium tuberculosis (eg, human immunodeficiency virus infection and selected medical conditions; recent immigrants to the United States from high TB-burden countries). The preferred regimen for the treatment of latent TB infection is 9 months of isoniazid. There is now renewed interest in and great need for the development of new drugs to treat TB and latent TB infection.

Objective This study was undertaken to investigate the rates and predictors of follow-up and treatment for postpartum patients with a positive purified protein derivative (PPD). Study design Retrospective cohort study of all women delivered at San Francisco General Hospital in 2000. All patients with a positive PPD were identified and their demographic and PPD follow-up and treatment data were collected and analyzed. Results Among the 1331 patients delivered, the prevalence of a positive PPD was 32% (n=425). Of the 393 patients who had not been previously treated, 42% (n=167) attended a follow-up visit with 42% of these (n=71) actually completing 6 months of therapy. Among different ethnicities, Asian patients were more likely to follow-up at a rate of 52% ( P =.03). Patients who received care from the same physician both antepartum and postpartum were more likely to attend and complete therapy at rates of 67% ( P P =.01), respectively. Conclusion We found that despite the opportunity given by the interaction with the medical system during pregnancy, only 18% of patients with a positive PPD actually completed therapy.

Recently, a short-course treatment using 60 daily doses of rifampin and pyrazinamide was recommended for latent tuberculosis (TB) infection (LTBI).To determine the acceptability, tolerability, and completion of treatment.Observational cohort study.Five county jails and TB outreach clinics for homeless populations in three cities.Study staff enrolled 1,211 patients (844 inmates and 367 homeless persons).Sites used 60 daily doses of rifampin and pyrazinamide, an approved treatment regimen for LTBI.Types and frequency of drug-related adverse events and outcomes of treatment.Prior to treatment, 25 of 1,178 patients (2.1%) had a serum aminotransferase measurement at least 2.5 times the upper limit of normal. Patients who reported excess alcohol use in the past 12 months were more likely than other patients to have an elevated pretreatment serum aminotransferase level (odds ratio, 2.1; 95% confidence interval, 1.1 to 6.1; p = 0.03). Treatment was stopped in 66 of 162 patients (13.4%) who had a drug-related adverse event. Among 715 patients who had serum aminotransferase measured during treatment, 43 patients (6.0%) had an elevation5 times the upper limits of normal, including one patient who died of liver failure attributed to treatment. In multivariate analyses, increasing age, an abnormal baseline aspartate aminotransferase level, and unemployment within the past 24 months were independent risk factors for hepatotoxicity. Completion rates were similar in jail inmates (47.5%) and homeless persons (43.6%).This study detected the first treatment-associated fatality with the rifampin and pyrazinamide regimen, prompting surveillance that detected unacceptable levels of hepatotoxicity and retraction of recommendations for its routine use. Completion rates for LTBI treatment using a short-course regimen exceeds historical rates using isoniazid. Efforts to identify an effective short-course treatment for LTBI should be given a high priority.

Recurrence of active tuberculosis after treatment can be due to relapse of infection with the same strain or reinfection with a new strain of Mycobacterium tuberculosis. The proportion of recurrent tuberculosis cases caused by reinfection has varied widely in previous studies. We evaluated cases of recurrent tuberculosis in two prospective clinical trials: a randomized study of two regimens for the last 4 months of treatment (n = 1,075) and a study of a twice-weekly rifabutin-containing regimen for human immunodeficiency virus-infected tuberculosis (n = 169). Isolates at diagnosis and from positive cultures after treatment completion underwent genotyping using IS6110 (with secondary genotyping for isolates with less than six copies of IS6110). Of 85 patients having a positive culture after completing treatment, 6 (7.1%) were classified as false-positive cultures by a review committee blinded to treatment assignment. Of the remaining 75 cases with recurrent tuberculosis and genotyping data available, 72 (96%; 95% confidence interval, 88.8-99.2%) paired isolates had the same genotype; only 3 (4%; 95% confidence interval, 0.8-11.2%) had a different genotype and were categorized as reinfection. We conclude that recurrent tuberculosis in the United States and Canada, countries with low rates of tuberculosis, is rarely due to reinfection with a new strain of M. tuberculosis.

The chronic granulomatous inflammation of sarcoidosis has been hypothesized to depend on the CD4+ T-helper lymphocyte. HIV infection, which depletes these cells, has been reported to attenuate the manifestations of sarcoidosis.We asked whether the development of symptomatic sarcoidosis in the context of preexisting HIV infection was dependent on the CD4+ lymphocyte count.We performed a retrospective standardized chart review of all patients who developed granulomatous inflammation following HIV infection at an urban academic referral center.We identified seven patients with sarcoidosis within this cohort and compared their CD4+ lymphocyte count to that in a cohort of 16 patients in whom similar granulomatous inflammation was found but who did not have sarcoidosis. We then compared our cases to all reported cases using a systematic literature review.The CD4+ lymphocyte count was200 cells/ microL in all of our patients with HIV infection when they developed subsequent sarcoidosis. In contrast, specific etiologies for granulomatous inflammation were found in all 10 HIV-infected patients who presented with granulomatous inflammation and a CD4+ lymphocyte count of200 cells/ microL, with infectious etiologies found in 8 patients. Similarly, there was relative preservation of the CD4+ lymphocyte count in previously reported cases, with 14 of 19 patients (74%) having an absolute CD4+ lymphocyte count of200 cells/ microL.We conclude that the development of the chronic granulomatous inflammation of sarcoidosis appears to depend on the preservation or restoration of the peripheral CD4+ lymphocyte count and that in most cases the CD4+ lymphocyte count exceeds 200 cells/ microL. Furthermore, alternative specific etiologies of granulomatous inflammation are generally identifiable in HIV-infected patients with peripheral CD4+ lymphocyte counts of200 cells/ microL.

The epidemiology of extrapulmonary tuberculosis (TB) is not well understood. We studied all cases of extrapulmonary TB reported in San Francisco during 1991-2000 to determine risk factors for extrapulmonary TB and the proportion caused by recent infection. Isolates were analyzed by IS6110-based restriction fragment-length polymorphisms analysis. There were 480 cases of extrapulmonary TB, of which 363 (76%) were culture positive; isolates were genotyped for 301 cases (83%). Multivariate analysis identified young age, female sex, and HIV infection as independent risk factors for nonrespiratory TB (excluding pulmonary, pleural, and disseminated TB). Pleural TB was less common in HIV-seropositive persons and women than were nonrespiratory forms of extrapulmonary TB. Pleural TB is different from other forms of extrapulmonary TB and is associated with the highest clustering rate (35% of cases) of all forms of TB. This high rate of clustering occurs because pleural TB is often an early manifestation of recent infection.

In HIV-infected patients with intrathoracic lymphadenopathy, it is not known whether clinical and radiographic findings are useful in predicting a specific diagnosis. We determined the etiology and predictors of the etiology of computed tomography (CT)-diagnosed intrathoracic lymphadenopathy in HIV-infected patients evaluated from June 1993 through April 1999. Multivariate analyses were performed to determine clinical and radiographic predictors of the three most common diagnoses. Of 318 patients, 110 (35%) had lymphadenopathy on chest CT. Among these 110 patients, tuberculosis/nontuberculous mycobacterial disease ( = 31), bacterial pneumonia ( = 26), and lymphoma ( = 21) were the most common diagnoses. Multivariate analysis identified cough and necrosis of lymph nodes on chest CT as independent predictors of tuberculosis/nontuberculous mycobacterial disease. African-American race, symptoms for 1 to 7 days, dyspnea, and presence of airways disease on chest CT were independent predictors of bacterial pneumonia; symptoms for >7 days, absence of cough, and absence of pulmonary nodules on CT independently predicted lymphoma. Intrathoracic lymphadenopathy is a frequent chest CT finding in HIV-infected patients. Opportunistic infections and lymphoma are the most common causes, and specific clinical and radiographic features can suggest these particular diagnoses.

Study objectives: To determine the etiology and the clinical and radiographic predictors of the etiology of pulmonary nodules in a group of HIV-infected patients. Design: Retrospective analysis. Setting: A large urban hospital in San Francisco, CA. Patients: HIV-infected patients evaluated at San Francisco General Hospital from June 1, 1993, through December 31, 1997, having one or more pulmonary nodules on chest CT. Main outcome measures: Three physicians reviewed medical records for clinical data and final diagnoses. Three chest radiologists blinded to clinical data reviewed chest CTs. Univariate and multivariate analyses were performed to determine clinical and radiographic predictors of having an opportunistic infection and the specific diagnoses of bacterial pneumonia and tuberculosis. Results: Eighty seven of 242 patients (36%) had one or more pulmonary nodules on chest CT. Among these 87 patients, opportunistic infections were the underlying etiology in 57 patients; bacterial pneumonia (30 patients) and tuberculosis (14 patients) were the most common infections identified. Multivariate analysis identified fever, cough, and size of nodules < 1c m on chest CT as independent predictors of having an opportunistic infection. Furthermore, a history of bacterial pneumonia, symptoms for 1 to 7 days, and size of nodules < 1c m on CT independently predicted a diagnosis of bacterial pneumonia; a history of homelessness, weight loss, and lymphadenopathy on CT independently predicted a diagnosis of tuberculosis. Conclusions: In HIV-infected patients having one or more pulmonary nodules on chest CT scan, opportunistic infections are the most common cause. Specific clinical and radiographic features can suggest particular opportunistic infections. (CHEST 2000; 117:1023‐1030)

Mechanical hyperventilation of acidemic patients with acute lung injury (ALI) requires the use of high volumes and pressures that may worsen lung injury. However, permissive hypercapnia in the presence of shock, metabolic acidosis, and multi-organ system dysfunction may compromise normal cellular function. Tris-hydroxymethyl aminomethane (THAM) may be an effective method to control acidosis in this circumstance. Protonated THAM is excreted by the kidneys, so that carbon dioxide production is not raised. In an uncontrolled study, we administered THAM to 10 patients with acidosis (mean pH = 7.14) and ALI (mean lung injury score = 3.28) in whom adequate control of arterial pH could not be maintained during either eucapnic ventilation or permissive hypercapnia ventilation. THAM was given at a mean dose of 0.55 mmol/kg/h. Administration of THAM was associated with significant improvements in arterial pH and base deficit, and a decrease in arterial carbon dioxide tension that could not be fully accounted for by ventilation. Although further studies are needed to confirm these observations, THAM appears to be an effective alternative to sodium bicarbonate for treating acidosis during ALI.

To determine whether the computed tomographic (CT) appearances of multiple pulmonary nodules in patients with acquired immunodeficiency syndrome (AIDS) can help differentiate the potential infectious and neoplastic causes.The thoracic CT scans obtained in 60 patients with AIDS and multiple pulmonary nodules were reviewed retrospectively by two thoracic radiologists who were blinded to clinical and pathologic data. The scans were evaluated for nodule size, distribution, and morphologic characteristics. CT findings were correlated with final diagnoses.Thirty-six (84%) of 43 patients with opportunistic infection had a predominance of nodules smaller than 1 cm in diameter, whereas 14 (82%) of 17 patients with a neoplasm had a predominance of nodules larger than 1 cm (P.001). Of the 43 patients with opportunistic infection, 28 (65%) had a centrilobular distribution of nodules; only one (6%) of 17 patients with a neoplasm had this distribution (P.001). Seven (88%) of eight patients with a peribronchovascular distribution had Kaposi sarcoma (P.001).In patients with AIDS who have multiple pulmonary nodules at CT, nodule size and distribution are useful in the differentiation of potential causes. Nodules smaller than 1 cm, especially those with a centrilobular distribution, are typically infectious. Nodules larger than 1 cm are often neoplastic. A peribronchovascular distribution is suggestive of Kaposi sarcoma.

Clinical and radiologic findings in a 73-year-old man who developed a systemic illness while receiving intravesical bacillus Calmette-Guérin (BCG) immunotherapy for bladder cancer are presented. Thin-section chest computed tomographic findings included a diffuse pattern of small nodules consistent with miliary disease. Potential mechanisms explaining the pulmonary disease resulting from intravesical BCG treatment include a hypersensitivity reaction or actual BCG infection of the lungs.

Rifampin and pyrazinamide are recommended for treatment of latent tuberculosis infection in adults without HIV infection, but reports of severe hepatotoxicity have raised concerns about its safety. Clinical trials have not compared this treatment with isoniazid in adults without HIV infection.To compare the safety and tolerance of a 2-month regimen of rifampin and pyrazinamide with that of a 6-month regimen of isoniazid for treatment of latent tuberculosis infection.Multicenter, prospective, open-label trial.Three urban public health tuberculosis clinics in the United States.589 adults with latent tuberculosis infection who met U.S. criteria for treatment.Patients were assigned in alternate weeks to receive rifampin and pyrazinamide daily for 2 months (n = 307) or isoniazid daily for 6 months (n = 282).Primary end points were hepatotoxicity, other adverse events, and percentage of patients who completed treatment.Sixteen of 207 (7.7%) patients assigned to rifampin and pyrazinamide developed grade 3 or 4 hepatotoxicity compared with 2 of 204 (1%) patients assigned to isoniazid (odds ratio, 8.46 [95% CI, 1.9 to 76.5]; P = 0.001). The rifampin plus pyrazinamide regimen was more likely than the isoniazid regimen to be discontinued because of hepatotoxicity (odds ratio, 5.19; P = 0.033). The overall percentage of nonhepatotoxic adverse events was 20% in the rifampin-pyrazinamide group and 16% in the isoniazid group. The proportion of patients who completed the study treatment was 61% and 57%, respectively.A 2-month regimen of rifampin and pyrazinamide was associated with an increased risk for grade 3 or 4 hepatotoxicity compared with a 6-month regimen of isoniazid. Liver enzymes should be measured routinely during treatment to screen for liver injury and prevent progression to severe toxicity.