dc.contributor.author |
Nyamogoba, Henry Dismas Nyabuto |
|
dc.date.accessioned |
2013-04-05T09:18:14Z |
|
dc.date.accessioned |
2013-07-19T07:52:33Z |
|
dc.date.available |
2013-04-05T09:18:14Z |
|
dc.date.available |
2013-07-19T07:52:33Z |
|
dc.date.issued |
2013-04-05 |
|
dc.identifier.uri |
http://hdl.handle.net/123456789/1760 |
|
dc.identifier.uri |
http://hdl.handle.net/123456789/1031 |
|
dc.description |
A thesis submitted in partial fulfillment for the degree of Doctor
of Philosophy in Medical Microbiology in the Jomo Kenyatta
University of Agriculture and Technology
2012 |
en_US |
dc.description.abstract |
Tuberculosis and human immunodeficiency virus co-infections have a global
prevalence with high morbidity and mortality rates. Non-tuberculous mycobacteria have
emerged as opportunistic pathogens among human immunodeficiency virus / acquired
immunodeficiency syndrome patients. Ziehl Neelsen smear microscopy initially used in
the diagnosis of tuberculosis fails to differentiate between tuberculous and nontuberculous
mycobacteria. This cross-sectional study was carried out between 2007 and
2009 at one provincial, one Level 5 and eight district hospitals in western Kenya to
determine the performance of Ziehl Neelsen smear microscopy and culture in the
diagnosis of tuberculosis among human immunodeficiency virus / acquired
immunodeficiency syndrome patients. It sought to determine the prevalence of
tuberculosis and human immunodeficiency virus infection, and tuberculosis - human
immunodeficiency virus co-infection rate in western Kenya. It also sought to determine
the clinical significance of non-tuberculous mycobacteria in western Kenya, and the
correlation between human immunodeficiency virus co-infection and resistance of
Mycobacterium tuberculosis to first-line anti-tuberculosis drugs isoniazid, rifampicin,
streptomycin and ethambutol. Sputa from 872 tuberculosis suspects underwent
microscopy and culture on solid and liquid media. Isolates were identified as
Mycobacterium tuberculosis or species of non-tuberculous mycobacteria using Hain’s
GenoType® Mycobacterium CM/AS Molecular Genetic Assay. Drug susceptibility
testing was done using the BACTEC MGIT 960 incubator. Hain’s GenoType
MTBDRplus Molecular Genetic Assay was also used to determine resistance to
xxii
isoniazid and rifampicin. Blood samples from 695 out of the 872 tuberculosis suspects
enrolled into the study were screened for human immunodeficiency virus infection
using Uni-GoldTM rapid test and positives confirmed with enzyme linked
immunosorbent assay. A questionnaire was used to collect demographic and medical
history data of the tuberculosis suspects. The Ziehl Neelsen smear positivity rate was
42.7% among the human immunodeficiency virus infected cases and 57.3% among the
non-infected cases. Culture positivity rate among the human immunodeficiency virus
infected cases was 46.4% and 53.6% among the non-infected cases. Tuberculosis
prevalence was 39.7% with disease significantly in males than females (P < 0.05).
Tuberculosis recurrence rate was 44.8% with no significant difference between the
genders (P > 0.05). Human immunodeficiency virus prevalence was 39.1% with
infection significantly higher among females than males (P < 0.05). Tuberculosis -
human immunodeficiency virus co-infection rate was 41.8% with no significant
difference in co-infection between the genders (P > 0.05). Non-tuberculous
mycobacterial disease prevalence was 1.72%. A total of 8 out of 12 Mycobacterium
tuberculosis mono-drug resistant isolates were from human immunodeficiency virus
infected cases. Ziehl Neelsen smear microscopy was inaccurate in the diagnosis of
tuberculosis among human immunodeficiency virus infected patients compared to
culture. Tuberculosis and human immunodeficiency virus / acquired immunodeficiency
syndrome prevalence were high in western Kenya. Tuberculosis recurrence rate was
high in western Kenya. Tuberculosis - human immunodeficiency virus co-infection rate
was high in western Kenya. Non-tuberculous mycobacteria played a significant role in
xxiii
causing tuberculosis-like disease which was misdiagnosed as tuberculosis. Antituberculosis
drug resistance was more among Mycobacterium tuberculosis isolates from
human immunodeficiency virus infected patients suggesting a positive correlation. A
more accurate diagnostic technique to augment Ziehl Neelsen smear microscopy is
needed to improve tuberculosis diagnosis among human immunodeficiency virus
infected patients. There is need to explore new approaches to childhood tuberculosis
diagnosis in order to increase case detection rate. The high prevalence of tuberculosis
and human immunodeficiency virus infection in western Kenya underscores the need
for more efforts and resources to increase knowledge and access healthcare. The high
tuberculosis recurrence rate observed in this study calls for studies to determine the
proportions of the disease attributable to endogenous re-activation and exogenous reinfection.
There is need to strengthen tuberculosis and human immunodeficiency virus /
acquired immunodeficiency syndrome collaborative activities to reduce morbidity and
mortality among co-infected patients. A more accurate diagnostic technique, a robust
scoring system and algorithms for non-tuberculous mycobacterial disease need to be
developed in order to enhance the diagnosis of the disease in Kenya. Large case-control
studies are imperative to identify risk factors and determine the contribution of nontuberculous
mycobacteria to tuberculosis-like disease among human immunodeficiency
virus / acquired immunodeficiency syndrome patients. Since no multi-drug resistant
tuberculosis was observed in this study, continued use and surveillance of resistance
trends to first-line anti-tuberculosis drugs would be prudent. |
en_US |
dc.description.sponsorship |
Dr. Gideon Kikuvi
JKUAT, Kenya
Dr. Solomon Mpoke
KEMRI, Kenya
Dr. Peter G. Waiyaki
KEMRI, Kenya |
en_US |
dc.language.iso |
en |
en_US |
dc.relation.ispartofseries |
PHD Medical Microbiology; |
|
dc.title |
Tuberculosis and human immunodeficiency virus co-infection and clinical significance of non-tuberculous mycobacteria in western Kenya |
en_US |
dc.type |
Thesis |
en_US |