Abstract
Background
A summary of factors associated with recurrent tuberculosis (TB) in the African HIV-infected population is lacking. We performed a systematic review to address this.
Methods
We performed a literature search within PubMed and The WHO Global Library with specific inclusion and exclusion criteria to identify manuscripts emanating from the African continent which potentially described factors associated with recurrent TB in persons living with HIV.
Results
The literature search yielded 52 unique manuscripts, of which only 4 manuscripts were included in the final systematic review following application of the inclusion and exclusion criteria. Baseline CD4 count, baseline HIV viral load, a positive tuberculin skin test, prior active TB disease, cutaneous hypersensitivity reaction to treatment, having < 3 lung zones affected by prior TB disease, and anaemia were associated with recurrent TB in HIV-infected individuals, whilst age and antiretroviral status were not.
Conclusion
The lack of studies describing recurrent TB in Africa which stratify results by HIV-status is a hindrance to understanding risk factors for recurrent TB in this population. This might be overcome by implementing guidelines related to the publishing of data from observational studies in peer-reviewed medical journals reporting recurrent TB in populations with a high-burden of HIV infection.
Keywords: published literature, tuberculosis recurrence, HIV, Africa
Introduction
Tuberculosis (TB) is a global health problem, with the African population amongst the populations with the highest burden of TB disease.1 This appears to be related to the high burden of HIV on the African continent. Indeed, HIV infection substantially increases the risk of developing future TB disease.1 Therefore, even HIV-infected individuals with a previous history of TB who might have been cured or successfully completed their TB treatment might develop TB again during their lifetime. This “recurrent” TB infection might be due to 1) a newly acquired infection with Mycobacterium tuberculosis following prior successful treatment for active TB disease, or 2) activation of latent M. tuberculosis from a previous exposure which did not result in active TB disease, or 3) activation of latent M. tuberculosis which remained following treatment completion for a prior episode of active TB disease.2 Persons with HIV infection have a higher risk of recurrent TB disease.1 In addition, there is significant mortality from TB infection in HIV infected persons.3 It is therefore important to identify additional factors associated with recurrent TB in the HIV-infected population to aid in the development of efficient risk-reduction interventions. The aim of this study was to conduct a systematic review of the published literature in order to identify additional risk factors for recurrent TB infection in people living with HIV/AIDS in Africa.
Methods
A formally registered protocol for this systematic review is unavailable. Briefly, we conducted a parallel search of PubMed and The WHO Global Library. In PubMed we searched using a combination of phrases/keywords and using a set of relevant MeSH terms (Table 1).
Table 1.
Database | Query | Search Terms | Number of Items Returned |
PubMed | 1 | Recurrence [MeSH Terms] | 150497 |
2 | Tuberculosis[MeSH Terms] | 162792 | |
3 | HIV [MeSH Terms] | 83568 | |
4 | Risk Factors [MeSH Terms] | 592615 | |
5 | Africa [MeSH Terms] | 191475 | |
6 | (((Recurrent) OR Recurrence) OR Recurring) OR Relapse [All Fields] |
560062 | |
7 | Tuberculosis [All Fields] | 219757 | |
8 | HIV [All Fields] | 287733 | |
9 | (Risk Factors) OR Predictors [All Fields] |
1024743 | |
10 | Africa [All Fields] | 249634 | |
11 | ((((Query #1) AND Query #2) AND Query #3) AND Query #4) AND Query #5 |
5 | |
12 | ((((Query #6) AND Query #7) AND Query #8) AND Query #9) AND Query #10 |
51 | |
13 | (Query #11) OR Query #12 | 51 | |
WHO Global Health Library |
1 | (Recurrence [MeSH Terms]) AND (Tuberculosis [MeSH Terms]) AND (HIV [MeSH Terms]) AND (Risk Factors [MeSH Terms]) AND (Africa [MeSH Terms]) |
12 |
We had chosen to search PubMed with both these options to improve the sensitivity of the search. In addition to the PubMed literature search, we also performed a search of literature in the World Health Organisation's (WHO) Global Medical Library using the same MeSH terms used in the PubMed search. We were unable to search EMBASE as our institution does not have access to the database. Abstracts of studies identified from the literature search were screened using the inclusion and exclusion criteria specified in Table 2.
Table 2.
Inclusion Criteria | Exclusion Criteria |
Original manuscripts published in English in peer reviewed journals |
Unpublished data, review manuscripts, case reports, commentaries, non-English manuscripts |
Research conducted in Africa | Research conducted outside Africa |
Studies reporting risk factors for recurrent TB in people living with HIV/AIDS |
Studies which do not report risk factors for recurrent TB in people living with HIV/AIDS |
Studies conducted in the general population | Research which does not involve the general population or focusses on specific population groups (For example, miners) |
Research in adults | Research in children |
The reference lists of included manuscripts were also hand searched for relevant studies which might not have been identified during the literature search. The quality of included studies was evaluated using the Newcastle-Ottawa Scale. We did not extend our search to “grey area” literature. Our decision to exclude data from “grey area” literature might have introduced publication bias, however the “grey area” literature is often not peer reviewed and in the case of conference abstracts, may not have provided enough information to be included in the review. Two authors independently screened the articles for inclusion in the review, and the opinion of an expert would be sought in the event of a dispute.
Manuscripts describing findings from HIV-positive populations (either studies solely of HIV-infected populations, or studies which stratified results by HIV status) were reviewed and the relevant data abstracted where possible. In addition to key risk factors for recurrent TB in HIV-infected individuals, the following data elements were extracted from all included manuscripts: Author, country where the study was conducted and year of publication; study design; size of HIV infected population; incidence of recurrent TB; % of cohort which was female; age; and CD4 count summary. Risk factors obtained from each study are primarily presented as a narrative. The characteristics of included studies are presented as descriptive statistics.
Results
The results of our literature search of the two databases are illustrated in Figure 1.
Our search yielded a total of 63 manuscripts. A total of 11 of these manuscripts were duplicates. Following review of the abstracts of the remaining 52 unique manuscripts,4–55 9 manuscripts7,15,18,23,25,26,31,33,35 were selected to undergo full text review. Reasons for exclusion of 43 manuscripts included: Not original manuscripts — 13 manuscripts;6,8,10,16,29,32,38,39,42,46,49,50,53 Not English — 3 manuscripts;30,40,45 Research in children – 6 manuscripts;4,12,17,27,47,48 Do not describe findings from a general population — 6 manuscripts;5,14,21,37,41,51 Studies which do not report risk factors for recurrent TB in people living with HIV/AIDS — 14 manuscrip ts.9,11,13,19,20,22,24,28,36,43,44,52,54,55 In addition there was one manuscript which reported on leprosy.34
Following full text screening of the 9 manuscripts,7,15,18,23,25,26,31,33,35 there were 5 manuscripts which were found not to specifically report risk factors for recurrent TB in people living with HIV/AIDS.7,15,26,33,35 In addition, we screened the reference lists of the remaining 4 manuscripts18,23,25,31 in order to identify other potentially eligible studies for inclusion in our systematic review, which did not yield any additional manuscripts. Therefore, this systematic review was comprised of 4 eligible manuscripts.18,23,25,31
A description of all eligible manuscripts evaluated in this systematic review is shown in Table 3.
Table 3.
Authors (Country, Year) |
Study Design | Total sample size analyzed (HIV-positives only) |
Incidence of recurrent TB (/100 py) |
% Female | Median Age | Median CD4+ count (Range) |
Study Quality (Newcastle-Ottawa Scale Score) |
Potential bias |
Lahey et al. (Tanzania, 2013) |
Prospective observational |
979 | HIV-positive with definite TB: 4.57 HIV-positive with definite/probable TB: 7.42 |
75.6 | Median age of HIV-positive patients with prior history of TB: 36.4 years |
HIV-positive patients with a prior history of TB: 347 (262–549) cells/µL |
7 | Selection, performance |
Houben et al. (Malawi, 2012) |
Prospective observational |
623 | HIV-positive not on ART: 3.9 HIV-positive on ART: 3.0 |
53.7 | Not specified. 50.6% of cohort <35 years |
Not specified | 8 | Performance |
Isanaka et al. (Tanzania, 2012) |
Sub-analysis of randomized controlled trial data |
Unclear | 12 events/644 person months and 11 events/704 person months in HIV-infected persons with non-iron deficiency anaemia and iron deficiency anaemia, respectively. |
Unclear | Unclear | Unclear | 8 | Selection, performance |
Hawken et al. (Kenya, 1993) |
Prospective observational |
58 | In patients with HIV-infection: 16.7 |
38.0% | Not reported. 65% of patients < 35 years old. |
Not reported | 8 | Selection |
Risk factors for recurrent TB in people living with HIV/AIDS were evaluated in participants from 4 studies conducted in 3 countries in Africa (Kenya, Malawi and Tanzania).18,23,25,31 Three of the eligible manuscripts describe prospective observational studies.18,23,31 One manuscript described the secondary analysis of data obtained from a randomized controlled trial.25 Females comprised 38%,18 54%23 and 76%31 of HIV-infected participants described in three of the eligible manuscripts. The remaining manuscript did not stratify results for gender by HIV status.25 The median age of HIV-infected participants in one manuscript was 36 years old.31 although median age was not specified in two manuscripts, approximately half of the HIV-infected study population was <35 years old in one manuscript,23 while this proportion was 65% in another manuscript.18 The remaining manuscript did not stratify results for age by HIV status.25 Median CD4 counts were reported in one of the 4 manuscripts only.31
There were several factors associated with a higher risk of developing recurrent TB infection identified in this systematic review. Risk factors for recurrent TB in people living with HIV/AIDS obtained from the full text review of eligible manuscripts are shown in Figure 2.
Most of these risk factors were identified from the study of Lahey et al,31 and included: Baseline CD4 count, baseline HIV viral load, and a positive tuberculin skin test. Factors which were not associated with a higher risk of recurrent TB in HIV-infected individuals reported in the study of Lahey et al,31 included ART status and age. In their study, Houben and colleagues conducted a sub-analysis of HIV-infected individuals but only investigated whether ART status was associated with recurrent TB infection in this population.23 As with the study of Lahey et al,31 the study of Houben and colleagues did not identify an association between ART status and recurrent TB in HIV-infected individuals.23 In the study conducted by Hawken and colleagues, there were two factors associated with a higher risk of recurrent TB in HIV-infected patients who had completed treatment: cutaneous hypersensitivity reaction to treatment and < 3 lung zones affected by prior TB disease.18 Isanaka et al., found that anaemia with or without iron-deficiency was associated with a 4- to 7-fold increased risk of recurrent tuberculosis in HIV-infected patients when potential confounders were accounted for.25
Discussion
Despite the high burden of HIV-TB co-infection on the African continent, there appears to be very little published peer-reviewed literature related to identifying risk factors for recurrent TB in HIV-infected individuals emanating from Africa. It is possible that the complexity of sharing data between TB and HIV programs (which have traditionally been vertical programs at African health care facilities),56 makes research related to HIV-TB co-infection very difficult. Therefore it is likely that collaborative activities between HIV and TB health services which have been shown to improve patient outcomes,57 might also improve research efforts as a consequence.
The risk factors for recurrent TB in HIV-infected individuals identified in this systematic review were essentially extracted from four manuscripts18,23,25,31 and included baseline CD4 count, baseline HIV viral load, a positive tuberculin skin test, cutaneous hypersensitivity reaction to treatment, having < 3 lung zones affected by prior TB disease, and anaemia. The findings of this systematic review have identified a gap in the current literature and highlight the important role of future clinical studies studying recurrent TB in the HIV-infected population. Due to the insufficient number of published manuscripts identified during the literature search, we were unable to perform a meta-analysis which could have provided pooled risk estimates for risk factors associated with recurrent TB in HIV-infected individuals in Africa. This further highlights the need for more research initiatives aimed at identifying risk factors for recurrent TB in HIV-infected individuals living in Africa, and further efforts to disseminate the findings of these studies through peer-reviewed manuscripts to the wider scientific community. This systematic review was also unable to provide information related to the stratification of recurrent TB into re-infection with M. tuberculosis or TB relapse. Before risk factors can be identified for these pathways leading to recurrent TB disease, adequately-powered genetic studies in African populations are required to accurately determine the burden of re-infection with M. tuberculosis and TB relapse.
Unfortunately, the lack of studies describing recurrent TB in Africa which stratify results by HIV-status is a hindrance to understanding risk factors for recurrent TB in this population. It is possible that implementing guidelines related to the publishing of observational studies in peer-reviewed medical journals reporting recurrent TB in populations with a high-burden of HIV infection might be a worthwhile approach to generating higher-level evidence for risk factors for recurrent TB in the form of systematic reviews and meta-analyses.
Acknowledgment
This work was supported through postdoctoral funding awarded by the South African National Research Foundation. The funding source played no role in designing the study; in the collection, analysis, and interpretation of data; in writing the report; or in the decision to submit this article for publication. The authors declare that there are no conflicts of interest.
References
- 1.Corbett EL, Marston B, Churchyard GJ, De Cock KM. Tuberculosis in sub-Saharan Africa: opportunities, challenges, and change in the era of antiretroviral treatment. Lancet. 2006;367:926–937. doi: 10.1016/S0140-6736(06)68383-9. [DOI] [PubMed] [Google Scholar]
- 2.Millet JP, Shaw E, Orcau A, Casals M, Miro JM, Cayla JA. Tuberculosis recurrence after completion treatment in a European city: reinfection or relapse? PLoS One. 2013;8:e64898. doi: 10.1371/journal.pone.0064898. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Mukadi YD, Maher D, Harries A. Tuberculosis case fatality rates in high HIV prevalence populations in sub-Saharan Africa. Aids. 2001;15:143–152. doi: 10.1097/00002030-200101260-00002. [DOI] [PubMed] [Google Scholar]
- 4.Bellamy R, Ruwende C, McAdam KP, et al. Mannose binding protein deficiency is not associated with malaria, hepatitis B carriage nor tuberculosis in Africans. Qjm. 1998;91:13–18. doi: 10.1093/qjmed/91.1.13. [DOI] [PubMed] [Google Scholar]
- 5.Charalambous S, Grant AD, Moloi V, et al. Contribution of reinfection to recurrent tuberculosis in South African gold miners. Int J Tuberc Lung Dis. 2008;12:942–948. [PubMed] [Google Scholar]
- 6.Crampin AC, Glynn JR, Fine PE. What has Karonga taught us? Tuberculosis studied over three decades. Int J Tuberc Lung Dis. 2009;13:153–164. [PMC free article] [PubMed] [Google Scholar]
- 7.Crampin AC, Mwaungulu JN, Mwaungulu FD, et al. Recurrent TB: relapse or reinfection? The effect of HIV in a general population cohort in Malawi. Aids. 2010;24:417–426. doi: 10.1097/QAD.0b013e32832f-51cf. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Daley CL. Tuberculosis recurrence in Africa: true relapse or re-infection? Lancet. 1993;342:756–757. doi: 10.1016/0140-6736(93)91535-t. [DOI] [PubMed] [Google Scholar]
- 9.De Cock KM, Colebunders R, Francis H, et al. Evaluation of the WHO clinical case definition for AIDS in rural Zaire. Aids. 1988;2:219–221. [PubMed] [Google Scholar]
- 10.Douglas JG, McLeod MJ. Pharmacokinetic factors in the modern drug treatment of tuberculosis. Clin Pharmacokinet. 1999;37:127–146. doi: 10.2165/00003088-199937020-00003. [DOI] [PubMed] [Google Scholar]
- 11.Feleke Y, Abdulkadir J, Aderaye G. Prevalence and clinical features of tuberculosis in Ethiopian diabetic patients. East Afr Med J. 1999;76:361–364. [PubMed] [Google Scholar]
- 12.Ferrand RA, Luethy R, Bwakura F, Mujuru H, Miller RF, Corbett EL. HIV infection presenting in older children and adolescents: a case series from Harare, Zimbabwe. Clin Infect Dis. 2007;44:874–878. doi: 10.1086/511878. [DOI] [PubMed] [Google Scholar]
- 13.Glynn JR, Warndorff DK, Fine PE, Munthali MM, Sichone W, Ponnighaus JM. Measurement and determinants of tuberculosis outcome in Karonga District, Malawi. Bull World Health Organ. 1998;76:295–305. [PMC free article] [PubMed] [Google Scholar]
- 14.Grant AD, Charalambous S, Fielding KL, et al. Effect of routine isoniazid preventive therapy on tuberculosis incidence among HIV-infected men in South Africa: a novel randomized incremental recruitment study. JAMA. 2005;293:2719–2725. doi: 10.1001/jama.293.22.2719. [DOI] [PubMed] [Google Scholar]
- 15.Gupta A, Wood R, Kaplan R, Bekker LG, Lawn SD. Tuberculosis incidence rates during 8 years of follow-up of an antiretroviral treatment cohort in South Africa: comparison with rates in the community. PLoS One. 2012;7:e34156. doi: 10.1371/journal.pone.0034156. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Harries AD, Hargreaves NJ, Salaniponi FM. Design of regimens for treating tuberculosis in patients with HIV infection, with particular reference to sub-Saharan Africa. Int J Tuberc Lung Dis. 2001;5:1109–1115. [PubMed] [Google Scholar]
- 17.Hashim MS, Salih MA, el Hag AA, et al. AIDS and HIV infection in Sudanese children: a clinical and epidemiological study. AIDS Patient Care STDS. 1997;11:331–337. doi: 10.1089/apc.1997.11.331. [DOI] [PubMed] [Google Scholar]
- 18.Hawken M, Nunn P, Gathua S, et al. Increased recurrence of tuberculosis in HIV-1-infected patients in Kenya. Lancet. 1993;342:332–337. doi: 10.1016/0140-6736(93)91474-z. [DOI] [PubMed] [Google Scholar]
- 19.Hesseling AC, Walzl G, Enarson DA, et al. Baseline sputum time to detection predicts month two culture conversion and relapse in non-HIV-infected patients. Int J Tuberc Lung Dis. 2010;14:560–570. [PubMed] [Google Scholar]
- 20.Hira SK, Ngandu N, Wadhawan D, et al. Clinical and epidemiological features of HIV infection at a referral clinic in Zambia. J Acquir Immune Defic Syndr. 1990;3:87–91. [PubMed] [Google Scholar]
- 21.Hnizdo E, Singh T, Churchyard G. Chronic pulmonary function impairment caused by initial and recurrent pulmonary tuberculosis following treatment. Thorax. 2000;55:32–38. doi: 10.1136/thorax.55.1.32. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Houben RM, Glynn JR, Mallard K, et al. Human immunodeficiency virus increases the risk of tuberculosis due to recent re-infection in individuals with latent infection. Int J Tuberc Lung Dis. 2010;14:909–915. [PMC free article] [PubMed] [Google Scholar]
- 23.Houben RM, Glynn JR, Mboma S, et al. The impact of HIV and ART on recurrent tuberculosis in a sub-Saharan setting. Aids. 2012;26:2233–2239. doi: 10.1097/QAD.0b013e32835958ed. [DOI] [PubMed] [Google Scholar]
- 24.Ipuge YA, Rieder HL, Enarson DA. Adverse cutaneous reactions to thiacetazone for tuberculosis treatment in Tanzania. Lancet. 1995;346:657–660. doi: 10.1016/S0140-6736(95)92278-4. [DOI] [PubMed] [Google Scholar]
- 25.Isanaka S, Mugusi F, Urassa W, et al. Iron deficiency and anemia predict mortality in patients with tuberculosis. J Nutr. 2012;142:350–357. doi: 10.3945/jn.111.144287. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Johnson JL, Okwera A, Vjecha MJ, et al. Risk factors for relapse in human immunodeficiency virus type 1 infected adults with pulmonary tuberculosis. Int J Tuberc Lung Dis. 1997;1:446–453. [PubMed] [Google Scholar]
- 27.Kabangila R, Semvua K, Rambau P, et al. Pulmonary histoplasmosis presenting as chronic productive cough, fever, and massive unilateral consolidation in a 15-year-old immune-competent boy: a case report. J Med Case Rep. 2011;5:374. doi: 10.1186/1752-1947-5-374. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 28.Kelly PM, Cumming RG, Kaldor JM. HIV and tuberculosis in rural sub-Saharan Africa: acohort study with two year follow-up. Trans R Soc Trop Med Hyg. 1999;93:287–293. doi: 10.1016/S0035-9203(99)90025-1. [DOI] [PubMed] [Google Scholar]
- 29.Kidenya BR, Webster LE, Behan S, et al. Epidemiology and genetic diversity of multidrug-resistant tuberculosis in East Africa. Tuberculosis (Edinb) 2014;94:1–7. doi: 10.1016/j.tube.2013.08.009. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 30.Kornaszewski W, Kornaszewska M, Skotnicki AB. [Acquired immunodeficiency syndrome (AIDS) in the African environment] Postepy Hig Med Dosw. 1986;40:331–346. [PubMed] [Google Scholar]
- 31.Lahey T, Mackenzie T, Arbeit RD, et al. Recurrent tuberculosis risk among HIV-infected adults in Tanzania with prior active tuberculosis. Clin Infect Dis. 2013;56:151–158. doi: 10.1093/cid/cis798. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 32.Lawn SD, Myer L, Badri M, Bekker LG, Wood R. Reply to Ouattara et al.: past history of tuberculosis is not a risk factor for incident tuberculosis during antiretroviral treatment in South Africa. Aids. 2007;21:388–389. doi: 10.1097/QAD.0b013e328011ec88. [DOI] [PubMed] [Google Scholar]
- 33.Lawn SD, Myer L, Bekker LG, Wood R. Burden of tuberculosis in an antiretroviral treatment programme in sub-Saharan Africa: impact on treatment outcomes and implications for tuberculosis control. Aids. 2006;20:1605–1612. doi: 10.1097/01.aids.0000238406.93249.cd. [DOI] [PubMed] [Google Scholar]
- 34.Lienhardt C, Kamate B, Jamet P, et al. Effect of HIV infection on leprosy: a three-year survey in Bamako, Mali. Int J Lepr Other Mycobact Dis. 1996;64:383–391. [PubMed] [Google Scholar]
- 35.Luzze H, Johnson DF, Dickman K, et al. Relapse more common than reinfection in recurrent tuberculosis 1–2 years post treatment in urban Uganda. Int J Tuberc Lung Dis. 2013;17:361–367. doi: 10.5588/ijtld.11.0692. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 36.Malkin JE, Prazuck T, Simonnet F, et al. Tuberculosis and human immunodeficiency virus infection in west Burkina Faso: clinical presentation and clinical evolution. Int J Tuberc Lung Dis. 1997;1:68–74. [PubMed] [Google Scholar]
- 37.Mallory KF, Churchyard GJ, Kleinschmidt I, De Cock KM, Corbett EL. The impact of HIV infection on recurrence of tuberculosis in South African gold miners. Int J Tuberc Lung Dis. 2000;4:455–462. [PubMed] [Google Scholar]
- 38.Marras TK, Daley CL. Epidemiology of human pulmonary infection with nontuberculous mycobacteria. Clin Chest Med. 2002;23:553–567. doi: 10.1016/S0272-5231(02)00019-9. [DOI] [PubMed] [Google Scholar]
- 39.Meintjes G, Rabie H, Wilkinson RJ, Cotton MF. Tuberculosis-associated immune reconstitution inflammatory syndrome and unmasking of tuberculosis by antiretroviral therapy. Clin Chest Med. 2009;30:797–810. doi: 10.1016/j.ccm.2009.08.013. [DOI] [PubMed] [Google Scholar]
- 40.Muganga N, Nkuadiolandu A, Mashako LM. [Clinical manifestations of AIDS in children in Kinshasa] Pediatrie. 1991;46:825–829. [PubMed] [Google Scholar]
- 41.Murray J, Sonnenberg P, Shearer S, Godfrey-Faussett P. Drug-resistant pulmonary tuberculosis in a cohort of southern African goldminers with a high prevalence of HIV infection. S Afr Med J. 2000;90:381–386. [PubMed] [Google Scholar]
- 42.Murray JF. Tuberculosis and HIV infection: global perspectives. Respirology. 1997;2:209–213. doi: 10.1111/j.1440-1843.1997.tb00081.x. [DOI] [PubMed] [Google Scholar]
- 43.Muture BN, Keraka MN, Kimuu PK, Kabiru EW, Ombeka VO, Oguya F. Factors associated with default from treatment among tuberculosis patients in Nairobi province, Kenya: a case control study. BMC Public Health. 2011;11:696. doi: 10.1186/1471-2458-11-696. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 44.Nicholas S, Sabapathy K, Ferreyra C, Varaine F, Pujades-Rodriguez M. Incidence of tuberculosis in HIV-infected patients before and after starting combined antiretroviral therapy in 8 sub-Saharan African HIV programs. J Acquir Immune Defic Syndr. 2011;57:311–318. doi: 10.1097/QAI.0b013e318218a713. [DOI] [PubMed] [Google Scholar]
- 45.Nicolas J. [AIDS in the African infant and child] Med Mal Infect. 1990;20:454–458. doi: 10.1016/s0399-077x(05)80819-4. [DOI] [PubMed] [Google Scholar]
- 46.Paul J. Royal Society of Tropical Medicine and Hygiene Meeting at Manson House, London, 12 December 1996. HIV and pneumococcal infection in Africa. Microbiological aspects. Trans R Soc Trop Med Hyg. 1997;91:632–637. doi: 10.1016/s0035-9203(97)90500-9. [DOI] [PubMed] [Google Scholar]
- 47.Rekha B, Swaminathan S. Childhood tuberculosis — global epidemiology and the impact of HIV. Paediatr Respir Rev. 2007;8:99–106. doi: 10.1016/j.prrv.2007.04.010. [DOI] [PubMed] [Google Scholar]
- 48.Schaaf HS, Krook S, Hollemans DW, Warren RM, Donald PR, Hesseling AC. Recurrent culture-confirmed tuberculosis in human immunodeficiency virus-infected children. Pediatr Infect Dis J. 2005;24:685–691. doi: 10.1097/01.inf.0000172933.22481.36. [DOI] [PubMed] [Google Scholar]
- 49.Scully C, Cawson RA, Porter SR. Acquired immune deficiency syndrome: review. Br Dent J. 1986;161:53–60. doi: 10.1038/sj.bdj.4805895. [DOI] [PubMed] [Google Scholar]
- 50.Semba RD, Darnton-Hill I, de Pee S. Addressing tuberculosis in the context of malnutrition and HIV coinfection. Food Nutr Bull. 2010;31:S345–S364. [PubMed] [Google Scholar]
- 51.Sonnenberg P, Murray J, Glynn JR, Shearer S, Kambashi B, Godfrey-Faussett P. HIV-1 and recurrence, relapse, and reinfection of tuberculosis after cure: a cohort study in South African mineworkers. Lancet. 2001;358:1687–1693. doi: 10.1016/S0140-6736(01)06712-5. [DOI] [PubMed] [Google Scholar]
- 52.Stein ME, Spencer D, Kantor A, Ruff P, Haim N, Bezwoda WR. Epidemic AIDS-related Kaposi's sarcoma in southern Africa: experience at the Johannesburg General Hospital (1980–1990) Trans R Soc Trop Med Hyg. 1994;88:434–436. doi: 10.1016/0035-9203(94)90419-7. [DOI] [PubMed] [Google Scholar]
- 53.Warren RM, van Helden PD. HIV-1 and tuberculosis infection. Lancet. 2002;359:1618–1619. doi: 10.1016/S0140-6736(02)08496-9. author reply 1619–1620. [DOI] [PubMed] [Google Scholar]
- 54.Whalen CC, Zalwango S, Chiunda A, et al. Secondary attack rate of tuberculosis in urban households in Kampala, Uganda. PLoS One. 2011;6:e16137. doi: 10.1371/journal.pone.0016137. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 55.Wilkinson D, Pillay M, Davies GR, Sturm AW. Resistance to antituberculosis drugs in rural South Africa: rates, patterns, risks, and transmission dynamics. Trans R Soc Trop Med Hyg. 1996;90:692–695. doi: 10.1016/s0035-9203(96)90440-x. [DOI] [PubMed] [Google Scholar]
- 56.Gunneberg C, Reid A, Williams BG, Floyd K, Nunn P. Global monitoring of collaborative TB-HIV activities. Int J Tuberc Lung Dis. 2008;12:2–7. [PubMed] [Google Scholar]
- 57.Howard AA, El-Sadr WM. Integration of tuberculosis and HIV services in sub-Saharan Africa: lessons learned. Clin Infect Dis. 2010;50(Suppl 3):S238–S244. doi: 10.1086/651497. [DOI] [PubMed] [Google Scholar]