A new preadmission staging system for predicting inpatient mortality from HIV-associated Pneumocystis carinii pneumonia in the early highly active antiretroviral therapy (HAART) era

Prognostic indicators in the World Health Organization's algorithm for seriously ill HIV-infected inpatients with suspected tuberculosis

BACKGROUND

Criteria for the 2007 WHO algorithm for diagnosing tuberculosis among HIV-infected seriously ill patients are the presence of one or more danger signs (respiratory rate > 30/min, heart rate > 120/min, temperature > 39 °C, and being unable to walk unaided) and cough ≥ 14 days. Determining predictors of poor outcomes among HIV-infected inpatients presenting with WHO danger signs could result in improved treatment and diagnostic algorithms.

METHODS

We conducted a prospective cohort study of inpatients presenting with any duration of cough and WHO danger signs to two regional hospitals in Cape Town, South Africa. The primary outcome was all-cause mortality up to 56 days post-discharge, and the secondary outcome a composite of any one of: hospital admission for > 7 days, died in hospital, transfer to a tertiary level or tuberculosis hospital. We first assessed the WHO danger signs as predictors of poor outcomes, then assessed the added value of other variables selected a priori for their ability to predict mortality in common respiratory opportunistic infections (CD4 count, body mass index (BMI), being on antiretroviral therapy (ART), hypotension, and confusion) by comparing the receiver operating characteristic (ROC) area under the curve (AUC) of the two multivariate models.

RESULTS

484 participants were enrolled, median age 36, 66% women, 53% had tuberculosis confirmed on culture. The 56-day mortality was 13.2%. Inability to walk unaided, low BMI, low CD4 count, and being on ART were independently associated with poor outcomes. The multivariate model of the WHO danger signs showed a ROC AUC of 0.649 (95% CI 0.582-0.717) for predicting 56-day mortality, which improved to ROC AUC of 0.740 (95% CI 0.681-0.800; p = 0.004 for comparison between the two ROC AUCs) with the multivariate model including the a priori selected variables. Findings were similar in sub-analyses of participants with culture-positive tuberculosis and with cough duration ≥ 14 days.

CONCLUSION

The study design prevented a rigorous evaluation of the prognostic value of the WHO danger signs. Our prognostic model could result in improved algorithms, but needs to be validated.

Classical versus alternative macrophage activation: the Ying and the Yang in host defense against pulmonary fungal infections

Macrophages are innate immune cells that possess unique abilities to polarize toward different phenotypes. Classically activated macrophages are known to have major roles in host defense against various microbial pathogens, including fungi, while alternatively activated macrophages are instrumental in immune-regulation and wound healing. Macrophages in the lungs are often the first responders to pulmonary fungal pathogens, and the macrophage polarization state has the potential to be a deciding factor in disease progression or resolution. This review discusses the distinct macrophage polarization states and their roles during pulmonary fungal infection. We focus primarily on Cryptococcus neoformans and Pneumocystis model systems as disease resolution of these two opportunistic fungal pathogens is linked to classically or alternatively activated macrophages, respectively. Further research considering macrophage polarization states that result in anti-fungal activity has the potential to provide a novel approach for the treatment of fungal infections.

Pneumocystis pneumonia in HIV-infected and immunocompromised non-HIV infected patients: a retrospective study of two centers in China

Background

Pneumocystis pneumonia (PCP) is an emerging infectious disease in immunocompromised hosts. However, the clinical characteristics of these patients are poorly understood in mainland China.

Methods

We performed a retrospective study of PCP from 2008 to 2012. Information was collected regarding clinical manifestations, hospitalization, and outcome. A prognostic analysis was performed using a Cox regression model.

Results

151 cases of PCP were included; 46 non-HIV and 105 HIV cases. All-cause mortality (15.2% vs. 12.4%, p = 0.64) and the results of time-to-event analysis (log-rank test, p = 0.62) were similar between non-HIV and HIV infected cases, respectively. From 2008 to 2012, time from admission to initial treatment in non-HIV infected PCP patients showed declining trend [median (range) 20 (9–44) vs. 12 (4–24) vs. 9 (2–23) vs. 7 (2–22) vs. 7 (1–14) days]. A similar trend was observed for all-cause mortality (33.3% vs. 20.0% vs.14.3% vs. 14.3% vs. 6.7%). Patients with four or more of the following clinical manifestations (cough, dyspnea, fever, chest pain, and weight loss) [adjusted HR (AHR) 29.06, 95% CI 2.13–396.36, P = 0.01] and admission to intensive care unit (ICU) [AHR 22.55, 95% CI 1.36–375.06, P = 0.03] were independently associated with all-cause mortality in non-HIV infected PCP patients. Variables associated with mortality in HIV infected PCP patients were admission to ICU (AHR 72.26, 95% CI 11.76–443.87, P<0.001) and albumin ≤30 g/L (AHR 9.93 95% CI 1.69–58.30, P = 0.01).

Conclusions

Upon admission comprehensive clinical assessment including assessment of four or more clinical manifestations (cough, dyspnea, fever, chest pain, and weight loss) in non-HIV infected PCP patients and albumin ≤30 g/L in HIV infected patients might improve prognosis.

Pneumocystis pneumonia associated with human immunodeficiency virus

Pneumocystis pneumonia (PCP) is caused by the yeastlike fungus Pneumocystis. Despite the widespread availability of specific anti-Pneumocystis prophylaxis and of combination antiretroviral therapy (ART), PCP remains a common AIDS-defining presentation. PCP is increasingly recognized among persons living in Africa. Pneumocystis cannot be cultured and bronchoalveolar lavage is the gold standard diagnostic test to diagnose PCP. Use of adjunctive biomarkers for diagnosis requires further evaluation. Trimethoprim-sulfamethoxazole remains the preferred first-line treatment regimen. In the era of ART, mortality from PCP is approximately 10% to 12%. The optimal time to start ART in a patient with PCP remains uncertain.

A prognostic scoring tool for identification of patients at high and low risk of death from HIV-associated Pneumocystis jirovecii pneumonia

A prognostic scoring tool (PST) was created to aid prediction of outcome from HIV-associated Pneumocystis jirovecii pneumonia (PCP) using data obtained from 577 episodes of PCP among 540 patients presenting to a specialist HIV treatment centre in London, UK. It used risk factors identifiable at/soon after hospitalization, previously identified as being associated with mortality: repeat episode of PCP, patient's age, haemoglobin (Hb) and oxygen partial pressure (PaO2) on admission, presence of medical co-morbidity (Comorb) and of pulmonary Kaposi sarcoma (PKS). The derived PST was 25.5+(age in years/10) + 2 (if a repeat episode of PCP) + 3 (if Comorb present) + 4 (if PKS detected) – PaO2 (kPa) – Hb (g/dL), and produced scores that ranged between 0 and 19. Patients were divided into five groups according to their prognostic score: 0-3.9 = group 1 (0% mortality), 4-7.9 = group 2 (3% mortality), 8-10.9 = group 3 (9% mortality), 11-14.9 = group 4 (29% mortality) and ≥15 = group 5 (52% mortality). This PST facilitates rapid identification of patients early in their hospitalization who have mild or severe HIV-associated PCP and who are at high and low risk of in-hospital death from PCP. The PST may aid assessment of severity of illness and in directing treatment strategies, but requires validation in patient cohorts from other healthcare institutions.

Characteristics and clinical relevance of the quantitative touch-down major surface glycoprotein polymerase chain reaction in the diagnosis of Pneumocystis pneumonia

The evaluation of quantitative polymerase chain reaction (PCR) characteristics can increase the accuracy of the laboratory diagnosis of Pneumocystis pneumonia (PCP). Between July 2008 and September 2009, 66 non-sequential prospective bronchoalveolar lavage (BAL) samples, obtained from five HIV-infected and 49 non HIV-infected patients were investigated, using a quantitative-touch-down-PCR to determine the number of copies of major surface glycoprotein (MSG) genes of Pneumocystis jirovecii (q-TD-MSG-PCR). PCP was confirmed by microscopic observation of Pneumocystis, radio-clinical and therapeutic data in 18/54 patients. For PCP, the cut-off was 54.3 MSG copies per ml of BAL fluid. The PCR was positive in these same 18 cases and it was the only positive assay in two cases and the earliest diagnosis test in one case of PCP relapse. The likelihood positive ratio, sensitivity and specificity of the q-TD-MSG-PCR were 44, 100% and 97.7%, respectively. The Predictive Negative Value was 100% and the Predictive Positive Value of 95.5%, the intra- and inter-assay variability values were 2.7% (at more than 30 MSG copies) and 11.7% (at 10,000 MSG copies), respectively. Quantitative PCR can help diagnose PCP even in cases of low Pneumocystis load and might decrease morbidity in association with very early specific treatments.

Seasonal variation in mortality of Pneumocystis jirovecii pneumonia in HIV-infected patients

A seasonal variation in the presentation of Pneumocystis jirovecii pneumonia (PCP) has been reported and a previous study from this centre noted a seasonal variation in mortality rates. This study examined seasonal influences (including climatic factors) within-host factors (clinical and laboratory-derived variables), the infectious burden of P. jirovecii in bronchoalveolar lavage (BAL) fluid, the presence of dihydropteroate synthase (DHPS) mutations in P. jirovecii, variations in knowledge and skills of junior medical staff, and mortality in 547 episodes of PCP occurring in 494 HIV-infected patients. The overall mortality rate was 13.5%. There was a seasonal variation in mortality: highest in autumn (21.2%) and lowest in spring (9.7%), P = 0.047. After adjustment was made for prognostic factors previously identified as being associated with mortality (increasing patient age, second/third episode of PCP, low haemoglobin, low PaO(2), presence of medical co-morbidity and pulmonary Kaposi sarcoma), there was no seasonal association with mortality, P = 0.249. The quantity of P. jirovecii DNA in BAL fluid showed no evidence of seasonal variation, P = 0.67; DHPS mutations were identified with equal frequency in each season and the mortality rate for February and August (when junior medical staff arrive in new posts) was 16.7%, only slightly greater than for other months (13.0%).

Predicting mortality from HIV-associated Pneumocystis pneumonia at illness presentation: an observational cohort study

BACKGROUND

Although the use of antiretroviral therapy has led to dramatic declines in AIDS-associated mortality, Pneumocystis pneumonia (PCP) remains a leading cause of death in HIV-infected patients.

OBJECTIVES

To measure mortality, identify predictors of mortality at time of illness presentation and derive a PCP mortality prediction rule that stratifies patients by risk for mortality.

METHODS

An observational cohort study with case note review of all HIV-infected persons with a laboratory diagnosis of PCP at San Francisco General Hospital from 1997 to 2006.

RESULTS

451 patients were diagnosed with PCP on 524 occasions. In-hospital mortality was 10.3%. Multivariate analysis identified five significant predictors of mortality: age (adjusted odds ratio (AOR) per 10-year increase, 1.69; 95% CI 1.08 to 2.65; p = 0.02); recent injection drug use (AOR 2.86; 95% CI 1.28 to 6.42; p = 0.01); total bilirubin >0.6 mg/dl (AOR 2.59; 95% CI 1.19 to 5.62; p = 0.02); serum albumin <3 g/dl (AOR 3.63; 95% CI 1.72-7.66; p = 0.001); and alveolar-arterial oxygen gradient >or=50 mm Hg (AOR 3.02; 95% CI 1.41 to 6.47; p = 0.004). Using these five predictors, a six-point PCP mortality prediction rule was derived that stratifies patients according to increasing risk of mortality: score 0-1, 4%; score 2-3, 12%; score 4-5, 48%.

CONCLUSIONS

The PCP mortality prediction rule stratifies patients by mortality risk at the time of illness presentation and should be validated as a clinical tool.

Pneumocystis murina colonization in immunocompetent surfactant protein A deficient mice following environmental exposure

Background

Pneumocystis spp. are opportunistic pathogens that cause pneumonia in immunocompromised humans and animals. Pneumocystis colonization has also been detected in immunocompetent hosts and may exacerbate other pulmonary diseases. Surfactant protein A (SP-A) is an innate host defense molecule and plays a role in the host response to Pneumocystis.

Methods

To analyze the role of SP-A in protecting the immunocompetent host from Pneumocystis colonization, the susceptibility of immunocompetent mice deficient in SP-A (KO) and wild-type (WT) mice to P. murina colonization was analyzed by reverse-transcriptase quantitative PCR (qPCR) and serum antibodies were measured by enzyme-linked immunosorbent assay (ELISA).

Results

Detection of P. murina specific serum antibodies in immunocompetent WT and KO mice indicated that the both strains of mice had been exposed to P. murina within the animal facility. However, P. murina mRNA was only detected by qPCR in the lungs of the KO mice. The incidence and level of the mRNA expression peaked at 8–10 weeks and declined to undetectable levels by 16–18 weeks. When the mice were immunosuppressed, P. murina cyst forms were also only detected in KO mice. P. murina mRNA was detected in SCID mice that had been exposed to KO mice, demonstrating that the immunocompetent KO mice are capable of transmitting the infection to immunodeficient mice. The pulmonary cellular response appeared to be responsible for the clearance of the colonization. More CD4+ and CD8+ T-cells were recovered from the lungs of immunocompetent KO mice than from WT mice, and the colonization in KO mice depleted CD4+ cells was not cleared.

Conclusion

These data support an important role for SP-A in protecting the immunocompetent host from P. murina colonization, and provide a model to study Pneumocystis colonization acquired via environmental exposure in humans. The results also illustrate the difficulties in keeping mice from exposure to P. murina even when housed under barrier conditions.

Outcome of HIV-associated Pneumocystis pneumonia in hospitalized patients from 2000 through 2003

BACKGROUND

Pneumocystis pneumonia (PCP) remains a leading cause of morbidity and mortality in HIV-infected persons. Epidemiology of PCP in the recent era of highly active antiretroviral therapy (HAART) is not well known and the impact of HAART on outcome of PCP has been debated.

AIM

To determine the epidemiology of PCP in HIV-infected patients and examine the impact of HAART on PCP outcome.

METHODS

We performed a retrospective cohort study of 262 patients diagnosed with PCP between January 2000 and December 2003 at a county hospital at an academic medical center. Death while in the hospital was the main outcome measure. Multivariate modeling was performed to determine predictors of mortality.

RESULTS

Overall hospital mortality was 11.6%. Mortality in patients requiring intensive care was 29.0%. The need for mechanical ventilation, development of a pneumothorax, and low serum albumin were independent predictors of increased mortality. One hundred and seven patients received HAART before hospitalization and 16 patients were started on HAART while in the hospital. HAART use either before or during hospitalization was not associated with mortality.

CONCLUSION

Overall hospital mortality and mortality predictors are similar to those reported earlier in the HAART era. PCP diagnoses in HAART users likely represented failing HAART regimens or non-compliance with HAART.

Acute lung injury outside of the ICU: incidence in respiratory isolation on a general ward

BACKGROUND

Epidemiologic investigations of acute lung injury (ALI) and ARDS have focused on mechanically ventilated patients in ICUs, and have reported high mortality rates. We sought to determine the incidence and lethality of these syndromes in the respiratory isolation areas of general wards, a non-ICU setting that often serves patients with acute lung processes.

METHODS

We prospectively studied all patients who were admitted to respiratory isolation rooms on the general wards of a large tertiary care hospital over a 1-year period. Patients were classified as having ALI or ARDS if they met consensus definitions for the syndromes. Characteristics and outcomes were compared to those of other patients who had been admitted to a respiratory isolation room with infiltrating lung disease but lacking bilateral infiltrates, hypoxemia, or both.

RESULTS

Of 715 patients admitted to respiratory isolation rooms on general wards, 474 (66%) had acute infiltrates. ALI criteria were met by 9% of patients (62 of 715 patients), with 2% of patients (15 of 715) satisfying the criteria for ARDS. Respiratory distress was present in 71% of ALI patients (44 of 62 patients) and 32% of patients (130 of 412 patients) with acute infiltrates who did not have ALI (p < 0.001). However, the 90-day survival rates (ALI patients, 88%; patients with acute infiltrates who did not have ALI, 90%) was similar between the two groups (p > 0.50).

CONCLUSIONS

ALI and ARDS may be frequent among patients who are admitted to respiratory isolation beds outside of ICUs. Mortality rates are substantially lower than those typically reported from surveys of ventilated ICU patients with ALI and ARDS.

Early predictors of mortality from Pneumocystis jirovecii pneumonia in HIV-infected patients: 1985-2006

BACKGROUND

Pneumocystis jirovecii pneumonia (PCP) remains the leading cause of opportunistic infection among human immunodeficiency virus (HIV)-infected persons. Previous studies of PCP that identified case-fatality risk factors involved small numbers of patients, were performed over few years, and often focused on patients who were admitted to the intensive care unit.

OBJECTIVE

The objective of this study was to identify case-fatality risk factors present at or soon after hospitalization among adult HIV-infected patients admitted to University College London Hospitals (London, United Kingdom) from June 1985 through June 2006.

PATIENTS AND METHODS

We performed a review of case notes for 494 consecutive patients with 547 episodes of laboratory-confirmed PCP.

RESULTS

Overall mortality was 13.5%. Mortality was 10.1% for the period from 1985 through 1989, 16.9% for the period from 1990 through June 1996, and 9.7% for the period from July 1996 through 2006 (P = .142). Multivariate analysis identified factors associated with risk of death, including increasing patient age (adjusted odds ratio [AOR], 1.54; 95% confidence interval [CI], 1.11-2.23; P = .011), subsequent episode of PCP (AOR, 2.27; 95% CI, 1.14-4.52; P = .019), low hemoglobin level at hospital admission (AOR, 0.70; 95% CI, 0.60-0.83; P < .001), low partial pressure of oxygen breathing room air at hospital admission (AOR, 0.70; 95% CI, 0.60-0.81; P < .001), presence of medical comorbidity (AOR, 3.93; 95% CI, 1.77-8.72; P = .001), and pulmonary Kaposi sarcoma (AOR, 6.95; 95% CI, 2.26-21.37; P = .001). Patients with a first episode of PCP were sicker (mean partial pressure of oxygen at admission +/- standard deviation, 9.3+/-2.0 kPa) than those with a second or third episode of PCP (mean partial pressure of oxygen at admission +/- standard deviation, 9.9+/-1.9 kPa; P = .008), but mortality among patients with a first episode of PCP (12.5%) was lower than mortality among patients with subsequent episodes of PCP (22.5%) (P = .019). No patient was receiving highly active antiretroviral therapy before presentation with PCP, and none began highly active antiretroviral therapy during treatment of PCP.

CONCLUSIONS

Mortality risk factors for PCP were identifiable at or soon after hospitalization. The trend towards improved outcome after June 1996 occurred in the absence of highly active antiretroviral therapy.

Developing Indicators of Inpatient Adverse Drug Events Through Nonlinear Analysis Using Administrative Data

BACKGROUND

Because of uniform availability, hospital administrative data are appealing for surveillance of adverse drug events (ADEs). Expert-generated surveillance rules that rely on the presence of International Classification of Diseases, 9th Revision Clinical Modification (ICD-9-CM) codes have limited accuracy. Rules based on nonlinear associations among all types of available administrative data may be more accurate.

OBJECTIVES

By applying hierarchically optimal classification tree analysis (HOCTA) to administrative data, derive and validate surveillance rules for bleeding/anticoagulation problems and delirium/psychosis.

RESEARCH DESIGN

Retrospective cohort design.

SUBJECTS

A random sample of 3987 admissions drawn from all 41 Utah acute-care hospitals in 2001 and 2003.

MEASURES

Professional nurse reviewers identified ADEs using implicit chart review. Pharmacists assigned Medical Dictionary for Regulatory Activities codes to ADE descriptions for identification of clinical groups of events. Hospitals provided patient demographic, admission, and ICD9-CM data.

RESULTS

Incidence proportions were 0.8% for drug-induced bleeding/anticoagulation problems and 1.0% for drug-induced delirium/psychosis. The model for bleeding had very good discrimination and sensitivity at 0.87 and 86% and fair positive predictive value (PPV) at 12%. The model for delirium had excellent sensitivity at 94%, good discrimination at 0.83, but low PPV at 3%. Poisoning and adverse event codes designed for the targeted ADEs had low sensitivities and, when forced in, degraded model accuracy.

CONCLUSIONS

Hierarchically optimal classification tree analysis is a promising method for rapidly developing clinically meaningful surveillance rules for administrative data. The resultant model for drug-induced bleeding and anticoagulation problems may be useful for retrospective ADE screening and rate estimation.

Improving outcome of human immunodeficiency virus-infected patients in a Mexican intensive care unit

BACKGROUND

In Latin America, insufficient data are available to improve local admission policies for human immunodeficiency virus (HIV) patients in the intensive care units (ICU). We undertook this study to evaluate the outcome and survival determinants of HIV patients in a Mexican ICU during three time periods.

METHODS

From December 1985 through January 2006, a clinical chart-based, retrospective study of all HIV patients admitted to the ICU was conducted. Demographic, clinical and laboratory data; disease severity score (APACHE II) and mortality were evaluated. A comprehensive database was created and data were analyzed using survival and regression models.

RESULTS

Ninety HIV patients were admitted to the ICU during the study: 16 (18%) in 1985-1992 (non-antiretroviral [ARV]-period), 21 (23%) in 1993-1996 (ARV-period), and 53 (58%) in 1996-2006 (highly active antiretroviral treatment [HAART] period). Leading reasons for admission were the need for mechanical ventilatory support (MVS, 85.5%), septic shock (23%), and non-HIV/AIDS complications (15.5%). Survival in the ICU increased from 12.5% (non-ARV period) to 57% (HAART period). Mortality during ICU stay was associated with MVS (HR: 3.2; 95% CI 1.0-10.2) and APACHE II > or =13 points (HR: 2.2; 95% CI 1.3-4.0). Use of steroids (HR: 0.4; 95% CI 0.2-0.8) and HAART (HR: 0.25; 95% CI 0.1-0.5) were associated with a lower risk of death. In multivariate analysis, septic shock was the main predictor of death in the ICU (HR: 2.4; 95% CI 1.1-5.2) and after discharge. HAART remained as a significant protective factor.

CONCLUSIONS

Overall survival in Mexican HIV patients admitted to an ICU has substantially increased in recent years. These data should encourage policies that consider HIV patients as good candidates for receiving intensive care.

The roles of low literacy and social support in predicting the preventability of hospital admission

BACKGROUND

Prior studies found higher hospitalization rates among patients with low literacy, but did not determine the preventability of these admissions or consider other determinants of hospitalization, such as social support. This study evaluated whether low literacy was a predictor for preventability of hospitalization when considered in the context of social support, sociodemographics, health status, and risk behaviors.

METHODS

A convenience sample of 400 patients, admitted to general medicine wards in a university-affiliated Veterans Affairs hospital between August 1, 2001 and April 1, 2003, completed a face-to-face interview to assess literacy, sociodemographics, social support, health status, and risk behaviors. Two Board-certified Internists independently assessed preventability of hospitalization and determined the primary preventable cause through blinded medical chart reviews.

RESULTS

Neither low literacy (<seventh grade) nor very low literacy (<fourth grade) was significantly associated with preventability of hospitalization. In multivariable analysis, significant predictors of having a preventable cause of hospitalization included binge alcohol drinking (P< or =.001), lower social support for medical care (P<.04), < or =3 annual clinic visits (P<.005), and > or =12 people talked to weekly (P<.023). Among nonbinge drinkers with lower social support for medical care, larger social networks were predictive of preventability of hospitalization. Among nonbinge drinkers with higher support for medical care, lower outpatient utilization was predictive of the preventability of hospitalization.

CONCLUSIONS

While low literacy was not predictive of admission preventability, the formal assessment of alcohol binge drinking, social support for medical care, social network size, and prior outpatient utilization may enhance our ability to predict the preventability of hospitalizations and develop targeted interventions.

Delays in suspicion and isolation among hospitalized persons with pulmonary tuberculosis at public and private US hospitals during 1996 to 1999

BACKGROUND

While prior studies have shown that public and private hospitals differ in their rates of suspicion and isolation of patients who are at risk for tuberculosis (TB), no study has investigated whether this variation is due to differences in the impact of patient case-mix on hospitals or to variations attributable to specific hospital practice patterns.

OBJECTIVE

To investigate patient-level and hospital-level factors associated with delays in TB suspicion and isolation among inpatients with pulmonary TB disease.

DESIGN

Retrospective cohort study of patients hospitalized with culture-positive pulmonary TB during 1996 to 1999.

SETTING

Patients with culture-proven pulmonary TB treated at three public hospitals (765 patients) and seven not-for-profit private hospitals (172 patients) in Chicago, Los Angeles, and southern Florida that provided care for five or more patients with TB per year during the study period.

MEASUREMENTS

Two-day rates (within 48 h from admission) of acid-fast bacilli (AFB) smear orders and 1-day rates (within 24 h from admission) of TB isolation.

RESULTS

Two-day rates of ordering AFB smears were > 80% at three public and two private hospitals vs 65 to 75% at five private hospitals. One-day rates of TB isolation at the three public hospitals were 64%, 79%, and 86%, respectively, vs 39 to 58% at the seven private hospitals. Delays of > 2 days in ordering AFB smears were associated with patient-level factors: absence of cough (adjusted odds ratio [AOR], 6.02; 95% confidence interval [CI], 3.82 to 9.52), cavitary lung lesion (AOR, 5.17; 95% CI, 1.98 to 13.50), night sweats (AOR, 3.38; 95% CI, 1.90 to 5.99), chills (AOR, 1.70; 95% CI, 1.01 to 2.88), and female gender (AOR, 1.66; 95% CI, 1.06 to 2.60). Delays of > 1 day in ordering pulmonary isolation were associated with patient-level factors: absence of cough (AOR, 3.40; 95% CI, 2.31 to 5.03), cavitary lung lesion (AOR, 2.66; 95% CI, 1.57 to 4.50), night sweats (AOR, 1.98; 95% CI, 1.35 to 2.92), and history of noninjecting drug use (AOR, 1.86; 95% CI, 1.16 to 2.99) and one hospital-level factor: receiving care at a nonpublic hospital. Even after adjustment for patient-level factors, TB patients at private hospitals were half as likely as those at public hospitals to be placed in pulmonary isolation (AOR, 0.47; 95% CI, 0.30 to 0.72), while odds of suspecting TB in these same patients were similar at both hospitals.

CONCLUSION

Private hospitals should order TB isolation for all patients for whom AFB smears are ordered, a policy that has been instituted previously at public hospitals in our study.

Design, synthesis, and computational affinity prediction of ester soft drugs as inhibitors of dihydrofolate reductase from Pneumocystis carinii

A series of dihydrofolate reductase (DHFR) inhibitors, where the methylenamino-bridge of non-classical inhibitors was replaced with an ester function, have been prepared as potential soft drugs intended for inhalation against Pneumocystis carinii pneumonia (PCP). Several of the new ester-based inhibitors that should serve as good substrates for the ubiquitous esterases and possibly constitute safer alternatives to metabolically stable DHFR inhibitors administered orally, were found to be potent inhibitors of P. carinii DHFR (pcDHFR). Although the objectives of the present program is to achieve a favorable toxicity profile by applying the soft drug concept, a high preference for inhibition of the fungal DHFR versus the mammalian DHFR is still desirable to suppress host toxicity at the site of administration. Compounds with a slight preference for the fungal enzyme were identified. The selection of the target compounds for synthesis was partly guided by an automated docking and scoring procedure as well as molecular dynamics simulations. The modest selectivity of the synthesized inhibitors was reasonably well predicted, although a correct ranking of the relative affinities was not successful in all cases.

US hospital care for patients with HIV infection and pneumonia: the role of public, private, and Veterans Affairs hospitals in the early highly active antiretroviral therapy era

STUDY OBJECTIVES

We evaluated differences in processes and outcomes of HIV-related pneumonia care among patients in Veterans Affairs (VA), public, and for-profit and not-for-profit private hospitals in the United States. We compared the results of our current study (1995 to 1997) with those of our previous study that included a sample of patients receiving care during the years 1987 to 1990 to determine how HIV-related pneumonia care had evolved over the last decade.

SETTING/PATIENTS

The sample consisted of 1,231 patients with HIV infection who received care for Pneumocystis carinii pneumonia (PCP) and 750 patients with HIV infection who received care for community-acquired pneumonia (CAP) during the years 1995 to 1997.

MEASUREMENT

We conducted a retrospective medical record review and evaluated patient and hospital characteristics, HIV-related processes of care (timely use of anti-PCP medications, adjunctive corticosteroids), non-HIV-related processes of care (timely use of CAP treatment medications, diagnostic testing, ICU utilization, rates of endotracheal ventilation, placement on respiratory isolation), length of inpatient hospital stay, and inpatient mortality.

RESULTS

Rates of timely use of antibiotics and adjunctive corticosteroids for treating PCP were high and improved dramatically from the prior decade. However, compliance with consensus guidelines that recommend < 8 h as the optimal time window for initiation of antibiotics to treat CAP was lower. For both PCP and CAP, variations in processes of care and lengths of in-hospital stays, but not mortality rates, were noted at VA, public, private not-for-profit hospitals, and for-profit hospitals.

CONCLUSIONS

This study provides the first overview of HIV-related pneumonia care in the early highly active antiretroviral therapy era, and contrasts current findings with those of a similarly conducted study from a decade earlier. Quality of care for patients with PCP improved, but further efforts are needed to facilitate the appropriate management of CAP. In the third decade of the epidemic, it will be important to monitor whether variations in processes of care for various HIV-related clinical diagnoses among different types of hospitals persist.

HIV-related pneumonia care in older patients hospitalized in the early HAART era

Age-related variations in care have been identified for HIV-associated Pneumocystis carinii pneumonia (PCP) in both the 1980s and 1990s. We evaluated if age-related variations affected all aspects of HIV-specific and non-HIV-specific care for HIV-infected individuals with PCP or community-acquired pneumonia (CAP), or whether age-related variations were primarily limited to HIV-specific aspects of care. Subjects were HIV-infected persons with PCP (n = 1855) or CAP (n = 1415) hospitalized in 8 cities from 1995 to 1997. Nine percent of our study patients had received protease inhibitors and 39% had received any type of antiretroviral therapy prior to hospitalization. Data were abstracted from medical records and included severity of illness, HIV-specific aspects of care (initiation of PCP medications), general measures of care [initiation of CAP medications, intubation, and intensive care units (ICU)], and inpatient mortality. Compared to younger patients, pneumonia patients 50 years of age or older were significantly more likely to: be severely ill (PCP, 20.4% vs. 10.4%; CAP, 27.5% vs. 14.9%; each p = 0.001), receive ICU care (PCP, 22.0% vs. 12.8%, p = 0.002; CAP: 15.1% vs. 9.4%; p = 0.02), and be intubated (PCP, 14.6% vs. 8.4%, p = 0.01; CAP, 9.9% vs. 5.6%, p = 0.03). Compared to younger patients, older patients (>/=50 years) had similar rates of timely medications for CAP (48.5% vs. 50.8%) but had lower rates of receiving anti-PCP medications (85.8% vs. 92.9%, p = 0.002). Differences by age in timely initiation of PCP medications, ICU use, and intubation were limited to the nonseverely ill patients. Older hospitalized patients were more likely to die (PCP, 18.3% vs. 10.4%; CAP, 13.4% vs. 8.5%; each p < 0.05). After adjustment for disease severity and timeliness of antibiotic use, mortality rates were similar for both age groups. Physicians should develop strategies that increase awareness of the possibility of HIV infection in older individuals.

Relationship between health insurance and medical care for patients hospitalized with human immunodeficiency virus-related Pneumocystis carinii pneumonia, 1995-1997: Medicaid, bronchoscopy, and survival

In the late 1980s, Medicaid-insured human immunodeficiency virus (HIV)-infected patients with Pneumocystis carinii pneumonia (PCP) were 40% less likely to undergo diagnostic bronchoscopy and 75% more likely to die than were privately insured patients, whereas rates of use of other, less resource-intensive aspects of PCP care were similar. We reviewed 1395 medical records at 59 hospitals in 6 cities for the period 1995-1997 to examine the impact of insurance status on PCP-related care. Medicaid patients were only one-half as likely to undergo diagnostic bronchoscopy as were privately insured patients, yet we found no evidence that mortality was greater among patients who received empirical treatment. The bronchoscopy rates were primarily related to patients' personal insurance status. A weaker hospital-level effect was seen that was related to hospitals' Medicaid/private insurance case mix ratios. The situation has evolved from one in which Medicaid coverage was associated with underuse of bronchoscopy and poorer survival among empirically treated persons with HIV-related PCP to one in which empirical therapy is effective in treating this disease and expensive diagnostic procedures may be overused for privately insured patients.

A rapid staging system for predicting mortality from HIV-associated community-acquired pneumonia

STUDY OBJECTIVE

Community-acquired pneumonia (CAP) accounts for an increasing proportion of the pulmonary infections in individuals with HIV infection. During the mid-1990s, hospital mortality rates for HIV-associated CAP ranged from 0 to 28%. While hospital differences in case mix may account for mortality rate variation, few methods to evaluate illness severity for HIV-associated CAP have been reported previously. The study objective was to develop a staging system for categorizing mortality risk of patients with HIV-associated CAP using information available prior to hospital admission.

DESIGN/SETTING/PATIENTS

Retrospective medical records review of 1,415 patients hospitalized with HIV-associated CAP from 1995 to 1997 at 86 hospitals in seven metropolitan areas.

MEASUREMENTS

In-patient mortality rate.

RESULTS

Hierarchically optimal classification tree analysis was used to develop a preadmission staging system for predicting inpatient mortality. The overall inpatient mortality rate was 9.1%. The significant predictors of mortality included the presence of neurologic symptoms, respiratory rate > or = 25 breaths/min, and creatinine > 1.2 mg/dL. The model identified a five-category staging system, with the mortality rate increasing by stage: 2.3% for stage 1, 5.8% for stage 2, 12.9% for stage 3, 22.0% for stage 4, and 40.5% for stage 5. The classification accuracy of the model was 85.2%.

CONCLUSIONS

Our staging system categorizes inpatient mortality risk for patients with HIV-associated CAP using three routinely available variables. The staging system may be useful for guiding clinical decisions about the intensity of patient care and for case-mix adjustment in future studies addressing variation in hospital mortality rates.

Intensive care of human immunodeficiency virus-infected patients during the era of highly active antiretroviral therapy

Highly active antiretroviral therapy for human immunodeficiency virus (HIV) infection has produced significant declines in morbidity and mortality from acquired immunodeficiency syndrome (AIDS). Whether this therapy has resulted in changes in epidemiology and outcomes of intensive care among HIV-infected patients is unknown. We performed chart review of all intensive care unit admissions for HIV-infected patients at San Francisco General Hospital from 1996 through 1999. There were an average of 88.5 admissions per year with 71% survival to hospital discharge. Univariate analysis demonstrated that prior highly active antiretroviral therapy (odds ratio [OR] = 1.8, p = 0.04), a non-AIDS-associated admission diagnosis (OR = 3.7, p = 0.001), a lower Acute Physiology and Chronic Health Evaluation II score (OR = 5.4, p = 0.001), and higher serum albumin (OR = 4.4, p = 0.001) predicted improved survival. Pneumocystis carinii pneumonia (OR = 0.24, p = 0.001), mechanical ventilation (OR = 0.19, p = 0.001), or a pneumothorax (OR = 0.08, p = 0.001) were associated with worse survival. In multivariate logistic regression, all variables except prior use of highly active antiretroviral therapy and pneumothorax were significant independent predictors of outcome. At our institution, overall survival for HIV-infected intensive care unit patients has improved, especially among patients receiving highly active antiretroviral therapy. These patients may have an improved survival because of effects of therapy on variables such as likelihood of non-AIDS-associated admission diagnoses and serum albumin levels.

Discontinuation of Pneumocystis carinii prophylaxis in patients infected with human immunodeficiency virus: a meta-analysis and decision analysis

We performed a meta-analysis and a decision analysis on the discontinuation of prophylaxis for Pneumocystis carinii pneumonia (PCP) in patients infected with human immunodeficiency virus who had adequate immune recovery while receiving highly active antiretroviral therapy. In the meta-analysis (14 studies with 3584 subjects who had discontinued prophylaxis), 8 cases of PCP occurred during 3449 person-years (0.23 cases per 100 person-years [95% confidence interval, 0.10-0.46]). In the decision analysis, mortality and time spent alive without immunodeficiency in the modeled discontinuation strategy were similar to those in the continuation strategy. For patients who received primary prophylaxis, the discontinuation strategy led to slightly fewer episodes of PCP and fewer toxicity-related prophylaxis withdrawals (e.g., 8.6 vs. 34.5 cases per 100 patients during a 10-year period). Patients on the discontinuation strategy were more likely to be receiving trimethoprim-sulfamethoxazole when they became immunodeficient. Comparative results were similar for patients with prior PCP. Discontinuation of PCP prophylaxis in patients with adequate immune recovery is a useful strategy that should be widely considered.

HIV-related Pneumocystis carinii pneumonia in older patients hospitalized in the early HAART era

OBJECTIVE

To determine whether older age continues to influence patterns of care and in-hospital mortality for hospitalized persons with HIV-related Pneumocystis carinii pneumonia (PCP), as determined in our prior study from the 1980s.

DESIGN

Retrospective chart review.

PATIENTS/SETTING

Patients (1,861) with HIV-related PCP at 78 hospitals in 8 cities from 1995 to 1997.

MEASUREMENTS

Medical record notation of possible HIV infection; alveolar-arterial oxygen gradient; CD4 lymphocyte count; presence or absence of wasting; timely use of anti-PCP medications; in-hospital mortality.

MAIN RESULTS

Compared to younger patients, patients > or =50 years of age were less likely to have HIV mentioned in their progress notes (70% vs 82%, P <.001), have mild or moderately severe PCP cases at admission (89% vs 96%, P <.002), receive anti-PCP medications within the first 2 days of hospitalization (86% vs 93%, P <.002), and survive hospitalization (82% vs 90%, P <.003). However, age was not a significant predictor of mortality after adjustment for severity of PCP and timeliness of therapy.

CONCLUSIONS

While inpatient PCP mortality has improved by 50% in the past decade, 2-fold age-related mortality differences persist. As in the 1980s, these differences are associated with lower rates of recognition of HIV, increased severity of illness at admission, and delays in initiation of PCP-specific treatments among older individuals--factors suggestive of delayed recognition of HIV infection, pneumonia, and PCP, respectively. Continued vigilance for the possibility of HIV and HIV-related PCP among persons > or =50 years of age who present with new pulmonary symptoms should be encouraged.

Design, synthesis, computational prediction, and biological evaluation of ester soft drugs as inhibitors of dihydrofolate reductase from Pneumocystis carinii

A series of lipophilic soft drugs structurally related to the nonclassical dihydrofolate reductase (DHFR) inhibitors trimetrexate and piritrexim have been designed, synthesized, and evaluated in DHFR assays, with special emphasis on the inhibition of P. carinii DHFR. The best inhibitors, encompassing an ester bond in the bridge connecting the two aromatic systems, were approximately 10 times less potent than trimetrexate and piritrexim. The metabolites were designed to be poor inhibitors. Furthermore, molecular dynamics simulations of three ligands in complex with DHFR from Pneumocystis carinii and from the human enzyme were conducted in order to better understand the factors determining the selectivity. A correct ranking of the relative inhibition of DHFR was achieved utilizing the linear interaction energy method. The soft drugs are intended for local administration. One representative ester was selected for a pharmacokinetic study in rats where it was found to undergo fast metabolic degradation to the predicted inactive metabolites.