Epidemiology of bloodstream infections and predictive factors of mortality among HIV-infected adult patients in Thailand in the era of highly active antiretroviral therapy

Few studies have described the pattern of bloodstream infections (BSI) among HIV-infected patients in the highly active antiretroviral therapy (HAART) era, particularly in resource-limited settings. A retrospective cohort study was conducted among 140 HIV-infected patients who had a positive blood culture from 2004-2008. Of the 140 patients, 91 (65%) were male with a mean (SD) age of 38 (9.1) years and a median (IQR) CD4 cell count of 32 (9-112) cells/mm(3). Community-acquired infection was detected in 89% of patients. The blood cultures contained Gram-negative bacteria, 40%; fungi, 24%; Mycobacterium spp., 20%; and Gram-positive bacteria, 16%. Common causative pathogens were Cryptococcus neoformans, 21%; Salmonella spp., 15%; and Mycobacterium tuberculosis, 12%. Common focal sites of infection were the central nervous system, 24%; respiratory tract, 20%; and gastrointestinal tract, 18%. CD4 cell count (OR, 0.61 per 50 cells/mm(3) increment; 95% CI, 0.39-0.96; P = 0.031) was the only factor associated with mycobacterial or fungal BSI. The crude mortality was 21%. HAART (OR, 0.23; 95% CI, 0.01-0.77; P = 0.017), focal infection (OR, 0.31; 95% CI, 0.10-0.97; P = 0.044), and complication (e.g., shock) (OR, 9.26; 95% CI, 3.25-26.42; P < 0.001) were the predictive factors of mortality. In conclusion, opportunistic infections are still the leading causes of BSI among HIV-infected patients in the HAART era.     

A superior test for diagnosis of Clostridium difficile-associated diarrhea in resource-limited settings

In this prospective cohort study, we investigated the prevalence of Clostridium difficile-associated diarrhea (CDAD) in adult patients with nosocomial diarrhea by performing enzyme immunoassay (EIA) for detecting toxins A and B and polymerase chain reaction (PCR) for detecting the presence of the tcdB gene in stool samples. We determined the factors associated with CDAD, and the treatment outcome of CDAD from May 2010 to January 2011. A total of 175 stool samples were tested by EIA and PCR. In total, 26.9% patients tested positive for C. difficile: 12.6% by EIA and 24.0% by PCR. The kappa coefficient and total agreement of both the tests were 0.46 and 83.2%, respectively. Onset of diarrhea after antibiotic administration for 10 days or more (OR, 2.71; 95% CI, 1.14-6.44; P = 0.024) and leukocyte count >15,000 cells/mm(3) (OR, 3.12; 95% CI, 1.24-7.88; P = 0.016) were significantly associated with occurrence of CDAD. The non-response rate to CDAD treatment was 24.1%, and the all-cause mortality rate was 31.9% in the CDAD group as against 35.9% in the non-CDAD group (P = 0.721). In our study, the performance of direct PCR of stool samples for detecting tcdB was better, with the number of positive results for stool toxins A and B being twofold higher than that in the case of EIA. Patients who have diarrhea after receiving antibiotics for 10 days or more or those who have a leukocyte count of >15,000 cells/mm(3) should be investigated for CDAD.