DNA restriction fragment length polymorphism analysis of Mycobacterium tuberculosis isolates from HIV-seropositive and HIV-seronegative patients in Kampala, Uganda.
BACKGROUND
The identification and differentiation of strains of Mycobacterium tuberculosis by DNA fingerprinting has provided a better understanding of the epidemiology and tracing the transmission of tuberculosis. We set out to determine if there was a relationship between the risk of belonging to a group of tuberculosis patients with identical mycobacterial DNA fingerprint patterns and the HIV sero-status of the individuals in a high TB incidence peri-urban setting of Kampala, Uganda.


METHODS
One hundred eighty three isolates of Mycobacterium tuberculosis from 80 HIV seropositive and 103 HIV seronegative patients were fingerprinted by standard IS6110-RFLP. Using the BioNumerics software, strains were considered to be clustered if at least one other patient had an isolate with identical RFLP pattern.


RESULTS
One hundred and eighteen different fingerprint patterns were obtained from the 183 isolates. There were 34 clusters containing 54% (99/183) of the patients (average cluster size of 2.9), and a majority (96.2%) of the strains possessed a high copy number (> or = 5 copies) of the IS6110 element. When strains with <5 bands were excluded from the analysis, 50.3% (92/183) were clustered, and there was no difference in the level of diversity of DNA fingerprints observed in the two sero-groups (adjusted odds ratio [aOR] 0.85, 95%CI 0.46-1.56, P = 0.615), patients aged <40 years (aOR 0.53, 95%CI 0.25-1.12, P = 0.100), and sex (aOR 1.12, 95%CI 0.60-2.06, P = 0.715).


CONCLUSIONS
The sample showed evidence of a high prevalence of recent transmission with a high average cluster size, but infection with an isolate with a fingerprint found to be part of a cluster was not associated with any demographic or clinical characteristics, including HIV status.
Asiimwe
Benon B
BB
Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77, Stockholm, Sweden. benon.asiimwe@ki.se
Joloba
Moses L
ML
Ghebremichael
Solomon
S
Koivula
Tuija
T
Kateete
David P
DP
Katabazi
Fred A
FA
Pennhag
Alexander
A
Petersson
Ramona
R
Kallenius
Gunilla
G
D017088:AIDS-Related Opportunistic Infections / Q000453:epidemiology / Q000382:microbiology; D000293:Adolescent; D000328:Adult; D015373:Bacterial Typing Techniques; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D005838:Genotype; D006679:HIV Seropositivity / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D009169:Mycobacterium tuberculosis / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D016017:Odds Ratio; D012150:Polymorphism, Restriction Fragment Length; D015995:Prevalence; D012307:Risk Factors; D017422:Sequence Analysis, DNA; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000382:microbiology; D014454:Uganda / Q000453:epidemiology; D055815:Young Adult
D004269:DNA, Bacterial