Tuberculosis during the first year of antiretroviral therapy in a South African cohort using an intensive pretreatment screening strategy.
OBJECTIVE
To determine the baseline prevalence of tuberculosis (TB) in a cohort using a strategy of intensive pretreatment screening for TB and the subsequent incidence rate and temporal distribution of cases during the first year of antiretroviral therapy (ART).


METHODS
Prospective observational community-based ART cohort in South Africa.


METHODS
Adults enrolling for ART and who did not have a current TB diagnosis were intensively screened for TB at baseline using culture of two sputum samples, chest radiography and investigations for extrapulmonary disease as required. Patients who developed symptoms consistent with incident TB during ART were similarly investigated.


RESULTS
Two hundred forty-one patients had a median CD4 cell count of 125 cells/microl (interquartile range 70-186) and 200 (83%) started ART. TB was diagnosed in 87 (36%) patients, with 82% of pulmonary cases being culture-proven. Most TB cases (87%) were prevalent disease detectable at baseline, whereas just 11 (13%) were incident cases that presented during the first year of ART. The incidence rate during 0-4 months of ART was similar to the rate during months 5-12 of ART [10.9 (95% confidence interval [CI] 4.6-23.3) cases per 100 person-years versus 8.1 (95% CI 3.6-18.0) cases per 100 person-years].


CONCLUSIONS
Systematic culture-based screening detected a very high burden of prevalent TB present at baseline. This intensified screening strategy was associated with an approximately two-fold lower incidence rate in the first 4 months of ART than previously observed in this cohort. This suggests that many incident cases of symptomatic TB presenting during early ART can be detected as prevalent disease prior to ART initiation using sensitive diagnostic tests.
Lawn
Stephen D
SD
The Desmond Tutu HIV Centre, Institute for Infectious Disease and Molecular Medicine, University of Cape Town, South Africa. stevelawn@yahoo.co.uk <stevelawn@yahoo.co.uk>
Kranzer
Katharina
K
Edwards
David J
DJ
McNally
Matthew
M
Bekker
Linda-Gail
LG
Wood
Robin
R
D017088:AIDS-Related Opportunistic Infections / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D000995:Antitubercular Agents / Q000008:administration & dosage; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000453:epidemiology; D015497:HIV-1; D006801:Humans; D008297:Male; D011247:Pregnancy; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D013019:South Africa / Q000453:epidemiology; D013183:Sputum / Q000821:virology; D011795:Surveys and Questionnaires; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*
D019380:Anti-HIV Agents; D000995:Antitubercular Agents
AIDS. 2009 Aug 24;23(13):1717-25
19461502
Sex Transm Infect. 2003 Aug;79(4):337-8
12902592
AIDS. 2007 Mar 30;21(6):713-9
17413692
Int J Tuberc Lung Dis. 2009 Jan;13(1):6-16
19105873
J Clin Microbiol. 2009 May;47(5):1287-9
19279173
Clin Infect Dis. 2009 Mar 15;48(6):829-31
19207078
AIDS. 2007 Jan 30;21(3):335-41
17255740
J Acquir Immune Defic Syndr. 2000 May 1;24(1):23-9
10877491
AIDS. 2008 Oct 1;22(15):1897-908
18784453
Am J Respir Crit Care Med. 2008 Apr 1;177(7):680-5
18202347
Lancet. 2006 Nov 4;368(9547):1575-80
17084757
Clin Chest Med. 2009 Dec;30(4):685-99, viii
19925961
Clin Infect Dis. 2009 Apr 1;48(7):856-62
19222372
Lancet. 2007 Jun 16;369(9578):2042-2049
17574096
J Acquir Immune Defic Syndr. 2009 Oct 1;52(2):145-51
19692904
Int J Tuberc Lung Dis. 2010 Jan;14(1):52-8
20003695
Am J Respir Crit Care Med. 2008 Apr 1;177(7):787-92
18202343
AIDS. 2006 Jun 12;20(9):1275-9
16816556
AIDS. 2009 Jan 2;23(1):143-5
19050399
Lancet Infect Dis. 2010 Feb;10(2):93-102
20113978
J Infect Dis. 2007 Aug 15;196 Suppl 1:S108-13
17624819
AIDS. 1993 Dec;7(12):1569-79
7904450
AIDS. 2005 Dec 2;19(18):2141-8
16284464
Lancet Infect Dis. 2009 Mar;9(3):173-84
19246021
AIDS. 2006 Aug 1;20(12):1605-12
16868441
AIDS. 2009 Sep 10;23(14):1875-80
20108382
J Infect Dis. 2007 Aug 15;196 Suppl 1:S15-27
17624822