862 
Asymptomatic Pulmonary TB among HIV-infected Adults Screened for the Botswana Isoniazid Preventive Therapy Clinical Trial, 2004-2006
Taraz Samandari*1,2, Taraz Samandari*1,2, T Agizew1, A Arwady1, J Yoon1, S Nyirenda1, B Mosimaneotsile1, Z Tedla1, O Motsamai3, P Kilmarx2, and C Wells2
1BOTUSA Project, Botswana; 2CDC, Atlanta, GA, US; and 3Natl TB Prgm, Ministry of Hlth, Gaborone, Botswana
Background: Isoniazid preventive therapy (IPT) is recommended for persons living
with HIV (PLWH) to prevent active tuberculosis (TB) in TB-endemic settings.
Based upon previous findings, the Botswana IPT Program guidelines recommend
that asymptomatic PLWH receive IPT without a screening chest radiograph (CXR).
As part of a 2000-person clinical trial to determine the efficacy of continuous
versus 6-month IPT, we sought to validate this recommendation among patients
enrolled in the clinical trial integrated with the National IPT Program.
Methods: PLWH referred from counseling and testing centers and local
clinics were screened in 2 steps. Screen-1 exclusion criteria (similar to the
National Program) included acute illness, recent TB treatment, liver disease,
or Karnofsky score <60. Screen-2 (trial-related)
exclusion criteria included abnormal CXR, elevated hepatic enzymes, significant
neutropenia, or anemia. Individuals with abnormal CXR
were later evaluated for pulmonary TB.
Results: Between November 2004 and June 2006, 4326 persons underwent
screen-1, and 2768 asymptomatic PLWH underwent screen-2. Of 4326 screenees, 1246 (29%) were excluded at screen-1; 61% because
of recent TB, acute illnesses, or AIDS-defining illnesses. At screen-2, 2768 screenees, 597 (22%) were excluded, of whom 50% had
abnormal CXR and 20% had neutropenia. Screen-2
subject characteristics included: median
CD4 lymphocyte count 308 cells/mm3 (range 4 to 1476), negative tuberculin
skin tests (75%), and taking ART (14%). Abnormal CXR potentially compatible
with TB were found in 336 of 2768 (12%). Abnormal findings included: 55% infiltrates, 25% hilar
adenopathy, 7% nodules, and 6% cavities. When detailed evaluations for TB were
conducted in 196 of 336 (58%) 0 to 13 months after the initial screening, 31
(9%) were found to have TB. Of the 336 individuals with abnormal baseline CXR,
97 initiated or completed a 6-month course of IPT. Of 97 patients, 2
subsequently developed TB, 1 of whom had isoniazid-resistant
disease. None of the remaining 95 (98%) developed TB after a median of 8 months
of observation.
Conclusions: Many PLWH seeking IPT in Botswana had advanced HIV disease
and were ineligible for the trial because of illness or abnormal CXR. Abnormal
CXR were common among asymptomatic PLWH seeking IPT. A significant portion of
these individuals developed TB. Further consideration of public health issues,
logistic factors, and cost-benefit analyses will help to inform National IPT
Program policy.
|
