Active and Latent Tuberculosis Screening Among HIV-infected Pregnant Women, Nayanza Province, Kenya
Maternal HIV/TB co-infection is associated with poor maternal and infant outcomes. Pregnancy provides a unique opportunity for TB screening and isoniazid preventative therapy. Our study objective is to determine prevalence and cofactors of active and latent TB infection (LTBI) and to evaluate performance of the WHO TB symptom screen and sputum Xpert for diagnosis/exclusion of active TB among pregnant HIV-infected women in Western Kenya.
This is an ongoing cross-sectional study of HIV-infected pregnant women in two maternal child health clinics in Nyanza Province, Kenya. All enrolled women undergo WHO TB symptom screening. Two sputum specimens are collected for smear and liquid culture, and one for Xpert performed at the CDC-KEMRI lab. Active TB was defined by at least one positive culture. Women with positive tuberculin skin test and negative culture were considered to have LTBI. Smear and Xpert were compared to the gold-standard of culture.
Between July 2013-April 2014, 188 women were enrolled who had median age 25 years (IQR 22-38), median CD4 of 413 cells/µL (IQR 308-552) and median gestational age of 27 weeks (IQR 20-32). Ten percent of women had a history of TB, 19% reported a history of TB contact, and 22% of women had at least one WHO TB screen symptom.
Among 125 women with finalized TB culture, prevalence of active TB was 4.0% (95% CI 0.5-7.5%). Individuals with active TB were 16-fold more likely to report a family member with a WHO TB screen symptom (PR 16.0 95% CI 3.4-75.3, p=0.012). Compared to culture, WHO symptom screen (60%), smear (0%), and Xpert (40%) had low sensitivity but high specificity (83%, 99%, and 100%, respectively). Cough >2 weeks was significantly associated with active TB (p=.006).
The prevalence of LTBI was 20.0% (95% CI 12.4-27.6%). Women with LTBI were older (median 27 vs 25 years, p=0.02) and more likely to be employed (77.3% vs 52.3%, PR 2.5 95% CI 1.0 - 6.4%, p=0.03); LTBI was not associated with CD4 count.
Prevalence of active pulmonary TB and LTBI was high among HIV-infected pregnant women. Active TB was associated with chronic cough and household member with TB symptoms and LTBI with employment and age. WHO TB symptom screen, smear, and Xpert were specific to exclude TB in pregnant HIV-infected women.
S. M. LaCourse,
J. Kinuthia, None
D. N. Matemo, None
G. C. John-Stewart, None
D. Horne, None