The Prevalence and Clinical Course of HIV-Associated Pulmonary Cryptococcosis in Uganda

Department of Medicine, Makerere University, Kampala, Uganda.
JAIDS Journal of Acquired Immune Deficiency Syndromes (Impact Factor: 4.56). 02/2010; 54(3):269-74. DOI: 10.1097/QAI.0b013e3181ce6b19
Source: PubMed


The prevalence and clinical course of pulmonary cryptococcosis in Sub-Saharan Africa are not well described.
Consecutive HIV-infected adults hospitalized at Mulago Hospital (Kampala, Uganda) between September 2007 and July 2008 with cough >or=2 weeks were enrolled. Patients with negative sputum smears for acid-fast bacilli were referred for bronchoscopy with bronchoalveolar lavage (BAL). BAL fluid was examined for mycobacteria, Pneumocystis jirovecii, and fungi. Patients were followed 2 and 6 months after hospital discharge.
Of 407 patients enrolled, 132 (32%) underwent bronchoscopy. Of 132 BAL fungal cultures, 15 (11%) grew Cryptococcus neoformans. None of the patients were suspected to have pulmonary cryptococcosis on admission. The median CD4 count among those with pulmonary cryptococcosis was 23 cells per microliter (interquartile range = 7-51). Of 13 patients who completed 6-month follow-up, 4 died and 9 were improved, including 5 who had started antiretroviral therapy but had not received antifungal medication.
Pulmonary cryptococcosis is common in HIV-infected tuberculosis suspects in Uganda. Early initiation of antiretroviral therapy in those with isolated pulmonary infection may improve outcomes, even without antifungal therapy. This finding suggests that some HIV-infected patients with C. neoformans isolated from respiratory samples may have colonization or localized infection.

Download full-text


Available from: Harriet N Kisembo
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Although antiretroviral therapy (ART) improves survival in persons with cryptococcal meningitis (CM) and AIDS, ART frequently elicits HIV immune reconstitution inflammatory syndrome (IRIS), an exaggerated and frequently deadly inflammatory reaction that complicates recovery from immunodeficiency. The pathogenesis of IRIS is poorly understood and prediction of IRIS is not possible. We prospectively followed 101 ART-naïve Ugandans with AIDS and recent CM for one year after initiating ART, and used Luminex multiplex assays to compare serum cytokine levels in participants who did or did not develop IRIS. IRIS occurred in 45% of participants with recent CM on ART, including 30% with central nervous system (CNS) manifestations. The median time to CM-IRIS was 8.8 wk on ART. Overall mortality on ART was 36% with IRIS and 21% without IRIS. CM-IRIS was independently associated with death (HR = 2.3, 95% CI 1.1-5.1, p = 0.04). Patients experiencing subsequent CM-IRIS had 4-fold higher median serum cryptococcal antigen (CRAG) levels pre-ART (p = 0.006). Higher pre-ART levels of interleukin (IL)-4 and IL-17 as well as lower tumor necrosis factor (TNF)-α, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and vascular endothelial growth factor (VEGF) predicted future IRIS in multivariate analyses (area under the curve [AUC] = 0.82). An algorithm based on seven pre-ART serum biomarkers was a robust tool for stratifying high (83%), moderate (48%), and low risk (23%) for IRIS in the cohort. After ART was initiated, increasing levels of C-reactive protein (CRP), D-dimer, IL-6, IL-7, IL-13, G-CSF, or IL-1RA were associated with increasing hazard of IRIS by time-to-event analysis (each p≤0.001). At the time of IRIS onset, multiple proinflammatory cytokine responses were present, including CRP and IL-6. Mortality was predicted by pre-ART increasing IL-17, decreasing GM-CSF, and CRP level >32 mg/l (highest quartile). Pre-ART CRP level >32 mg/l alone was associated with future death (OR = 8.3, 95% CI 2.7-25.6, p<0.001). Pre-ART increases in Th(17) and Th(2) responses (e.g., IL-17, IL-4) and lack of proinflammatory cytokine responses (e.g., TNF-α, G-CSF, GM-CSF, VEGF) predispose individuals to subsequent IRIS, perhaps as biomarkers of immune dysfunction and poor initial clearance of CRAG. Although requiring validation, these biomarkers might be an objective tool to stratify the risk of CM-IRIS and death, and could be used clinically to guide when to start ART or use prophylactic interventions.
    Full-text · Article · Dec 2010 · PLoS Medicine
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Nucleic acid amplification tests are sensitive for identifying Mycobacterium tuberculosis in populations with positive sputum smears for acid-fast bacilli, but less sensitive in sputum-smear-negative populations. Few studies have evaluated the clinical impact of these tests in low-income countries with high burdens of TB and HIV. We prospectively enrolled 211 consecutive adults with cough ≥2 weeks and negative sputum smears at Mulago Hospital in Kampala, Uganda. We tested a single early-morning sputum specimen for Mycobacterium tuberculosis DNA using two nucleic acid amplification tests: a novel in-house polymerase chain reaction targeting the mycobacterial secA1 gene, and the commercial Amplified® Mycobacterium tuberculosis Direct (MTD) test (Gen-Probe Inc, San Diego, CA). We calculated the diagnostic accuracy of these index tests in reference to a primary microbiologic gold standard (positive mycobacterial culture of sputum or bronchoalveolar lavage fluid), and measured their likely clinical impact on additional tuberculosis cases detected among those not prescribed initial TB treatment. Of 211 patients enrolled, 170 (81%) were HIV-seropositive, with median CD4+ T-cell count 78 cells/µL (interquartile range 29-203). Among HIV-seropositive patients, 94 (55%) reported taking co-trimoxazole prophylaxis and 29 (17%) reported taking antiretroviral therapy. Seventy-five patients (36%) had culture-confirmed TB. Sensitivity of MTD was 39% (95% CI 28-51) and that of secA1 was 24% (95% CI 15-35). Both tests had specificities of 95% (95% CI 90-98). The MTD test correctly identified 18 (24%) TB patients not treated at discharge and led to a 72% relative increase in the smear-negative case detection rate. The secA1 and MTD nucleic acid amplification tests had moderate sensitivity and high specificity for TB in a predominantly HIV-seropositive population with negative sputum smears. Although newer, more sensitive nucleic acid assays may enhance detection of Mycobacterium tuberculosis in sputum, even currently available tests can provide substantial clinical impact in smear-negative populations.
    Full-text · Article · Jan 2011 · PLoS ONE
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cryptococcosis is an invasive fungal infection (IFI), caused predominantly by Cryptococcus neoformans or Cryptococcus gattii, that affects both immunocompromised (IC) and non-IC patients. Although the most serious disease manifestation is meningoencephalitis, cryptococcal pneumonia is underdiagnosed and may disseminate to the central nervous system (CNS) and other sites depending upon host defenses and administration of appropriate antifungal therapy. The clinical presentation of pulmonary cryptococcosis varies along a spectrum from asymptomatic infection to severe pneumonia and respiratory failure, and the radiological presentation can be characterized by an array of findings, including nodules, consolidation, cavitary lesions, and a diffuse interstitial pattern. Diagnosis most often relies upon isolation of Cryptococcus from a pulmonary specimen in the appropriate clinical and radiological context. Treatment recommendations include induction therapy with an amphotericin B preparation and flucytosine for IC patients and those with severe disease and fluconazole for mild-to-moderate, localized disease. Knowledge of the pathophysiology, epidemiology, clinical presentation, and treatment of pulmonary cryptococcosis may lead to greater recognition of this underdiagnosed IFI and improved outcomes.
    No preview · Article · Dec 2011 · Seminars in Respiratory and Critical Care Medicine
Show more