Blood cultures for the diagnosis of multidrug-resistant and extensively drug-resistant tuberculosis among HIV-infected patients from rural South Africa: a cross-sectional study
1 Tugela Ferry Care and Research Collaboration (TF CARES), Tugela Ferry, South Africa
2 University of Virginia, Charlottesville, VA, USA
3 Albert Einstein College of Medicine and Montefiore Medical Center, New York, NY, USA
4 Philanjalo Care Center and Church of Scotland Hospital, Tugela Ferry, South Africa
5 National Health Laboratory Services, Durban, South Africa
6 Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
7 Yale University School of Medicine, New Haven, CT, USA
BMC Infectious Diseases 2010, 10:344 doi:10.1186/1471-2334-10-344Published: 6 December 2010
The yield of mycobacterial blood cultures for multidrug-resistant (MDR) and extensively drug-resistant tuberculosis (XDR-TB) among drug-resistant TB suspects has not been described.
We performed a retrospective, cross-sectional analysis to determine the yield of mycobacterial blood cultures for MDR-TB and XDR-TB among patients suspected of drug-resistant TB from rural South Africa. Secondary outcomes included risk factors of Mycobacterium tuberculosis bacteremia and the additive yield of mycobacterial blood cultures compared to sputum culture.
From 9/1/2006 to 12/31/2008, 130 patients suspected of drug-resistant TB were evaluated with mycobacterial blood culture. Each patient had a single mycobacterial blood culture with 41 (32%) positive for M. tuberculosis, of which 20 (49%) were XDR-TB and 8 (20%) were MDR-TB. One hundred fourteen (88%) patients were known to be HIV-infected. Patients on antiretroviral therapy were significantly less likely to have a positive blood culture for M. tuberculosis (p = 0.002). The diagnosis of MDR or XDR-TB was made by blood culture alone in 12 patients.
Mycobacterial blood cultures provided an additive yield for diagnosis of drug-resistant TB in patients with HIV from rural South Africa. The use of mycobacterial blood cultures should be considered in all patients suspected of drug-resistant TB in similar settings.