Tuberculosis

A number of randomized controlled trials have shown that isoniazid preventive therapy (IPT) to reduce the incidence of active TB disease in people living with HIV.

A Cochrane review of 11 trials involving 8,130 randomized participants showed that IPT reduced the risk of active TB by 33%.

A recent randomized, double-blind placebo controlled trial in Botswana found that isoniazid preventive therapy (IPT) taken for 36 months was more effective than a 6-month course in significantly reducing risk of TB incidence in people with HIV.

A retrospective analysis evaluated the impact of IPT on mortality of 3,258 HIV-positive miners in South Africa who initiated IPT and found that the mortality rate was significantly lower, with a 53% reduction in mortality among those on IPT than among those who did not receive IPT.

A study in Ethiopia that assessed the effect of HAAART on patient mortality and TB incidence rates under routine clinical care conditions in 2003 found that HAART resulted in a 65% decline in mortality and the TB incidence rate was lower in the HAART group. HAART improved survival and decreased TB incidence to a level similar to that achieved in developed countries during the early years of HAART. In August 2003, the hospital started providing HAART to patients. All HIV-positive patients who visited the clinic since January 2003 were followed and treated for opportunistic infections. Patients who were followed from January 2003 to August 2003 were the “pre-HAART cohort” and patients followed from August 2003 to August 2005 were the “HAART cohort.” The last day of pre-HAART followed was April 1, 2004. After April 1, 2004 all patients of this hospital who met the Ethiopian HAART treatment guidelines had access to HAART at this hospital. Pre-HAART patients who joined the HAART group contributed person-time to both cohorts at different periods. A cohort of 90 men and 95 women, or a total of 185 patients were followed prior to accessing HAART. A cohort of 102 men and 78 women, for a total cohort of 180 patients were followed in the HAART cohort. At the end of the pre-HAART period, 10 patients (5.4%) were lost to follow-up; 8 (4.3%) were transferred to another health institution; 47 (25.4%) died and 120 (64.9%) were under regular follow-up. The pre-HAAART mortality rate was 58.1 per 100 person-years of observation. TB incidence rate with HAART was reduced by almost 90%. Community agents visited patients on a monthly basis in the patient’s home. Community agents received training and had completed secondary school. Community agents reported the patient’s status to the hospital following each visit to the patient’s home.

A multi-center cohort study in Spain of 2,238 HIV-seroconverters compared TB incidence in pre-HAART and HAART eras and found that the risk of developing TB was 70% lower in the HAART era than in the pre-HAART era.

Among a cohort of 346 patients receiving HAART in Cape Town, South Africa TB incidence was highest among patients with CD4 counts under 100 and those with WHO clinical stage 3 or 4 disease. Risk for TB was independently associated with CD4 count, and WHO stage 3 or 4 disease. Incidence of TB continued to decrease during the first 5 years of HAART.

From February 2003 through January 2004, 2,342 patients were registered for TB treatment in Ubon-ratchathani, Thailand. Of these, 225 (10%) were confirmed as HIV-positive prior to their TB diagnosis, and of the remaining 2,117 patients, 680 agreed to be tested for HIV, and 104/680 (15%) were found to be HIV-positive. The 329 (14%) TB patients with confirmed HIV diagnoses were followed prospectively to assess the impact of HAART on TB treatment outcomes. Among the 290 TB patients with known outcomes, 71 were on HAART and 219 were not. Death during TB treatment occurred in 7% (5 of 71) on HAART and 43% (94 of the 219) not on HAART. Antiretroviral therapy was associated with a significant reduction in deaths among those on HAART prior to initiating TB treatment.

Pregnant HIV-positive women who have active TB are at higher risk for mortality. “There is a strong evidence base for screening pregnant HIV- infected women for TB as part of antenatal care. Intensified case finding for TB can reduce morbidity and mortality and prevent transmission of TB in families, the community, and health care settings. Delaying the diagnosis of active TB significantly increases the proportion of infected contacts” . “Although there is a wealth of evidence suggesting that screening for active TB during routine antenatal care would be a beneficial intervention, especially in places with efficient PMTCT program, no country programs have implemented this strategy as part of best practices” (DeLuca et al., 2009: 198).

At two PMTCT program clinics in Soweto, South Africa, 370 HIV-positive pregnant women were screened for TB symptoms by lay counselors during post- test counseling sessions. Eight women were found to have previously undiagnosed, smear-negative TB disease. Active screening for TB symptoms is feasible..

Clients accessing antenatal clients, TB patients, and medical providers from five health facilities in Kasungu District, Malawi were interviewed to assess the acceptability of TB screening and TB treatment. Most clients found screening acceptable but expressed concern about HIV stigma. All of the service providers agreed that TB screening was important but expressed concern about the increased workload.