Mycobacterium tuberculosis Beijing Strain, Bamako, Mali

To the Editor: Mycobacterium tuberculosis has >36 identifi ed genotype families (1). Four genotypes cause 35% of documented cases of active tuberculosis (TB): Beijing (10%– 11%), Latin American–Mediterranean (9.3%), Haarlem (7.5%), and the X clade (7%) (1,2) The Beijing clade strains, reported in 1995 from the Peo-ple's Republic of China, are widely recognized as highly pathogenic with a possible predilection for multidrug resistance (3). Predominant in Asia, these strains have been documented in other parts of the world (1,4,5). The virulence, propensity to become resistant , and distinct geographic distribution of the Beijing clade suggest it may have some adaptive advantage in producing disease in humans. Limited data suggest that its presence in Africa is low (2,4,5). In Bamako, Mali, 2 patients with active pulmonary TB came to the research clinic at Point G Hospital, af-fi liated with the University of Bamako Medical School, for recruitment under a US National Institute of Allergy and Infectious Diseases' institutional review board–approved protocol. The fi rst patient, a previously healthy 34-year-old man, sought treatment in March 2008. He had a 3-month history of fever, cough, shortness of breath, and left-sided chest pain; respiratory rate of 24/min; temperature of 36.8ºC; and pulse rate of 68/ min. He weighed 60 kg. His leuko-cyte count was 8,700 cells/μL, and he was positive for HIV-1 with a CD4+ T-cell count of 468 cells/μL. He reported contact with persons from other countries in Africa, China, and other parts of Asia. Chest radiograph showed a cavi-tary lesion on the left upper lobe and opacities throughout the left lung. Three sputum samples collected 3 days apart were digested and decontaminated with N-acetyl-L-cysteine, 4% NaOH; concentrated by high-speed centrifugation; stained with auramine-rhodamine; and evaluated by using fl uorescent microscopy. The many acid-fast bacilli (AFB) seen were identifi ed by using nucleic acid probes (AccuProbe, Gen-Probe, San Diego CA, USA). Antimycobacterial drug susceptibility was determined by using a manual indirect susceptibility test (mycobacterial growth indicator tube,) showed the isolate sensitive to isoniazid (0.1 μg/mL), rifampin (1.0 μg/mL), and ethambutol (3.5 μg/mL) but resistant to streptomycin (0.8 μg/ mL). Spoligotyping using a commercially available kit (Spoligotyping Isogen Life Science, De Meern, the Netherlands) showed characteristics of the Beijing clade (online Appendix Figure, panel A, www.cdc.gov/EID/ content/16/2/362-appF.htm) (6). The patient began treatment with the standard fi rst-line regimen of iso-niazid, rifampin, pyrazinamide, and ethambutol fi xed-dose combination (Svizera Laboratory, Mumbai, India) according to Malian …