Samuel D. Yoo

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BACKGROUND Although World Health Organization guidelines recommend clinical judgment and chest radiography for diagnosing tuberculosis in HIV-infected adults with unexplained cough and negative sputum smears for acid-fast bacilli, the diagnostic performance of this approach is unknown. Therefore, we sought to assess the accuracy of symptoms, physical signs,(More)
BACKGROUND T-cell interferon-gamma release assays (IGRAs) may have a role in the diagnosis of active tuberculosis when evaluating patients for whom standard microbiology has limited sensitivity. Our objective was to examine the accuracy of a commercial IGRA for diagnosis of active tuberculosis in HIV-infected persons. METHODS We enrolled HIV-infected(More)
OBJECTIVE To determine the need for routine speciation of positive Lowenstein-Jensen mycobacterial cultures in HIV-infected patients suspected of having pulmonary tuberculosis at Mulago Hospital in Kampala, Uganda. METHODS Sputum and bronchoalveolar lavage Lowenstein-Jensen mycobacterial culture isolates from consecutive, HIV-infected patients admitted to(More)
SETTING Mulago national referral and teaching hospital. OBJECTIVE To assess the etiology of lower respiratory infections in HIV-infected Ugandan adults who are sputum acid-fast bacilli (AFB) smear-negative. DESIGN A descriptive cross-sectional study. Participants included consecutive adult patients admitted to medical wards with respiratory symptoms of(More)
BACKGROUND Respiratory infections are a leading cause of death in Africa, especially among HIV-infected patients. Data on the etiology of fatal respiratory diseases are largely based on autopsy studies. We evaluated causes of pneumonia associated with early mortality among hospitalized HIV-infected patients in Kampala, Uganda. METHODS Prospective cohort(More)
BACKGROUND Sputum concentration increases the sensitivity of smear microscopy for the diagnosis of tuberculosis (TB), but few studies have investigated this method in human immunodeficiency virus (HIV)-infected individuals. METHODS We performed a prospective, blinded evaluation of direct and concentrated Ziehl-Neelsen smear microscopy on a single(More)
BACKGROUND Cryptococcal infection occurs in HIV-seropositive patients and is associated with high mortality. However, limited information is available on the prevalence and outcomes of cryptococcal antigenemia among hospitalized HIV-seropositive patients in sub-Saharan Africa. OBJECTIVES To determine the prevalence of and risk factors for cryptococcal(More)
BACKGROUND Peripheral blood interferon-gamma release assays (IGRAs) have sub-optimal sensitivity and specificity for diagnosis of active pulmonary tuberculosis (TB). However, assessment of local immune responses has been reported to improve the accuracy of TB diagnosis. METHODS We enrolled HIV-infected adults with cough ≥2 weeks' duration admitted to(More)
Pneumocystis jirovecii pneumonia (PCP) is an important opportunistic infection in patients infected with HIV, but its burden is incompletely characterized in those areas of sub-Saharan Africa where HIV is prevalent. We explored the prevalence of both PCP in HIV-infected adults admitted with pneumonia to a tertiary-care hospital in Uganda and of putative P.(More)