Posted on

HIV infection and mycobacterium tuberculosis drug-resistance among tuberculosis patients in Burkina Faso, West Africa

L Sangaré, S Diandé, G Ouédraogo, A.S Traoré

 

Abstract

The aim of this study was to compare the drug-resistance patterns of Mycobacterium tuberculosis strains among pulmonary tuberculosis patients, according to their HIV serostatus, in Burkina Faso. Tuberculosis (TB) patients were classified in new and previously treated cases by using a structured questionnaire. Susceptibility testing to isoniazid, streptomycin, rifampicin and ethambutol was done by the proportion method. Association between HIV-serostatus and drug-resistant TB was assessed with χ2 tests, and the statistical significance was set to P<0.05. Of 316 (249 new, 67 previously treated) patients included in the study, 68.7% were males and 28.8% were HIV-positive; females (36.4%) were more infected than males
(25.3%), (P=0.04). The average age of the patients was 37.24±12.76 years [11-75years]. Most of the patients infected with HIV were aged from 15 to 44 years and were females, (P=0.01). In the new cases of TB, the difference between HIV-positive and HIV-negative patients was not statistically significant neither for the MDR-TB (P=0.40), nor for the resistant-TB to any drug (P=0.26). However, the difference was significant for the resistance to isoniazid and streptomycin alone (P=0.04). Among the previously treated patients, although there was more MDR-TB and more resistance to any drug in HIV-negative patients than among HIV-positive patients, these differences also were not statistically significant (P=0.54 and P=0.63, respectively). This study found no significant difference between TB/HIV-negative and TB/HIV-positive patients according to the resistance patterns to anti-TB medications, excepted the resistance to isoniazid in new cases and to isoniazid and streptomycin in all patients took globally. These results encourage the collaboration between the programs against TB and HIV to prevent rapid diffusion of drug-resistant TB and high mortality in patients living with HIV/AIDS as recommended by the World Health Organization.

Keywords: Tuberculosis, HIV, Drug resistance, Burkina Faso

Download full journal in PDF below

HIV infection and mycobacterium tuberculosis drug-resistance among tuberculosis patients in Burkina Faso, West Africa

Posted on

COMPARATIVE STUDY ON SPECIFIC AND EARLY DETECTION OF PULMONARY MYCOBACTERIA COMPLEX USING SMEAR AND CULTURE METHOD AND SEROLOGICAL PATHOZYME EIA KITS

CA Enwuru, EO Idigbe, NV Ezeobi, CT Oparaugo, U Udensi Kalu, JI Onyewuche, J Ibiam

 

Abstract

The objective of this study was to compare the sensitivity and specificity of smear and culture methods with rapid serological EIA myco kits manufactured by Omega diagnostics, for the early detection of Mycobacterium tuberculosis (MTB) complex. Sera from various categories of smear and culture results were compared with the result of 38KDa, 16KDa and purified protein for IgA, IgM and IgG antibodies with sensitivity of 4%, 24% and 76%, respectively and with specificity of100% for IgG in Smear and Culture Positive (S+)C+)) category. The sensitivity of the test improved to a level of 80% for IgG + IgA without affecting the specificity. A combination of IgG + IgA and IgM further improved the sensitivity to 88% but reduced the specificity to 91%. Amongst the S–)C+) and S–)C–) 64% and 14.7% were positive for IgG respectively. The predictive value of the kit using S+)C+) subject was 96%. For all culture positivity (n=78), there was 2.6%, 33.3% and 71.8% sensitivity for IgA, IgM and IgG respectively. IgA +IgG and IgA + IgM + IgG combination gave 74.4% and 84.6% sensitivity respectively with the same level of specificity. Fifty-five percent of culture positive subjects were found to be MTB complex positive by routine biochemical tests, while 40% through PATHOZYME TB COMPLEX PLUS kit (high positive (H+)) values). When high positivity is combined with low positivity of the same kit (H+) + L+)), 65% of the isolates were found to be MTB complex. Our study showed 88% sensitivity and 91% specificity for combined IgA + IgM + IgG antibodies recorded for MTB (S+)C+) group) and 85% sensitivity and 91% specificity for all culture positives. Our study has demonstrated that the myco kits and TB complex plus kit produced by Omega Diagnostics are a good tool for specific, early and rapid identification of active tuberculosis for both diagnostic and epidemiological purposes.

Key Words: Tuberculosis, diagnosis, comparative, specificity, sensitivity, culture and serological technique.

Afr. J. Clin. Exper. Microbiol. 2004; 5(2): 182 – 188.

Posted on

PHAGE AMPLIFICATION TECHNOLOGY AND ANTI-TUBERCULOUS DRUG SUSCEPTIBILITY TESTING IN NIGERIA

E.J. Otive-Igbuzor

 

Abstract

The emergence of multi-drug resistant tuberculosis (MDR-TB) defined as combined resistance to the two most effective anti-tuberculosis drugs, rifampicin and isoniazid, threatens to create a public health hazard of unprecedented proportion. The fact that MDR-TR is more difficult and expensive to cure creates the need for prompt diagnosis. Conventionally, the proportion method on Lowenstein Jensen (L J) medium is used in most developing countries as the ‘gold standard’ in the drug susceptibility testing of Mycobacterium tuberculosis (MTB) and it takes 3-4 weeks to give results from an MTB culture. The use of phage as a diagnostic is fast gaining ground today. It involves targeting viable MTB cells from culture with a specific mycobacteriophage. After a one-hour incubation, it is treated with an antivirus to destroy the phages that are not protected with the bacilli. Upon addition of cells of growing, non-pathogenic Mycobacterium smegmatis (sensor cells), progeny phage from the MTB cells infect the sensor cells, thus amplifying the effect of the phage. When plated in an agar medium overnight, plaques occur in the cell lawn indicating the presence of viable MTB in an original sample. A comparison is made between the number of plaques produced in a drug-free control and a sample incubated in the presence of the drug. While the presence of plaques beyond a cut-of point indicates drug resistance, the absence of plaques indicates that the drug destroyed MTB cells. Overall accuracy from several trials so far conducted is put at 97-98% compared with the ‘gold standard’. With the phage amplification method, antituberculosis drug susceptibility results are obtained from MTB culture within 48 hours as opposed to the L J proportion method, which gives resulted in 3 to 4 weeks. Also, phage, as a diagnostic, is much more applicable in Nigeria laboratories than newer, rapid methods which requires specially dedicated instrumentation and are therefore very expensive. Phage amplification technology requires no special equipment and the results can be read visually.

Key words: Tuberculosis, drug susceptibility, phage, treatment, FASTPlaque-TB, rifampicin

(Af J Clinical & Exp Microbiology: 2003 4(2): 67-78)