Detection of Mycobacterium tuberculosis in sputum in patients coinfected with HIV / tuberculosis by various methods (literature review)

Abstract

The review presents the special aspects of bacillary excretion in tuberculosis patients co-infected with HIV and the yield of acid-fast smear depending on the CD4-cell count. Predictors of positive growth of Mycobacterium tuberculosis from sputum under negative microscopy in this category of patients are considered. The experience of different countries of the world on the effectiveness of various diagnostic algorithms for detecting tuberculosis in HIV/TB co-infection and the role of molecular-genetic methods in the diagnosis of tuberculosis are discussed. According to the data presented in the review, the yield of acid-fast sputum smear microscopy varies significantly, and depends on a variety of factors, including the immune status of the patient with HIV infection, the level of the laboratory service. The different yield of the smear microscopy in combination with the subclinical course of tuberculosis and atypical radiologic presentation in patients with HIV infection leads to a delay in diagnosis and to late initiation of antituberculosis therapy. The culture and the molecular-genetic methods of sputum examination increase the frequency of detection of the pathogen, however, the diagnosis of tuberculosis by culture can not be considered rapid in patients with immunodeficiency. Therefore, in the context of the continuing increase in the number of patients with co-infection, rapid, molecular-genetic methods for the detection of MTB DNA should be included in the algorithm for screening for tuberculosis of HIV- infected patients during their first encounter with the healthcare system.