Impact of expanded antiretroviral use on incidence and prevalence of tuberculosis in children with HIV in Kenya.

SETTING: Antiretroviral therapy (ART) reduces pulmonary tuberculosis (PTB) in human immunodeficiency virus (HIV) infected children. Recent ART recommendations have increased the number of children on ART. OBJECTIVE: To determine the prevalence and incidence of TB in HIV-infected children after the implementation of expanded ART guidelines. DESIGN: A prospective cohort study including HIV-infected children aged 6 weeks to 14 years was conducted in Kenya. The primary outcome measure was clinically diagnosed TB. Study participants were screened for prevalent TB at enrollment using Kenya's national guidelines and followed at monthly intervals to detect incident TB. Predictors of TB were assessed using logistic regression and Cox proportional hazards regression. RESULTS: Of 689 participants (median age 6.4 years), 509 (73.9%) were on ART at baseline. There were 51 cases of prevalent TB (7.4%) and 10 incident cases, with over 720.3 child-years of observation (incidence 1.4 per 100 child-years). Months on ART (adjusted hazard ratio [aHR] 0.91, P = 0.003; aOR 0.91, P< 0.001) and months in care before ART (aHR 0.87, P= 0.001; aOR 0.92, P < 0.001) were protective against incident and prevalent TB. CONCLUSIONS: ART was protective against TB in this cohort of HIV-infected children with high levels of ART use. Optimal TB prevention strategies should emphasize early ART in children.

Validation of a new clinical scoring system for acute bronchitis.

INTRODUCTION: Although several clinical prediction rules exist for lower respiratory tract infection (LRTI), few are for acute bronchitis (acute bronchitis) and most have not been validated in high human immunodeficiency virus (HIV) prevalence settings. METHODS: An Acute Bronchitis Severity Score (ABSS) was developed and validated during a randomized trial of antibiotic treatment for acute bronchitis. Ambulatory adults with productive cough of < or =2 weeks at out-patient respiratory disease clinics in Nairobi, Kenya, were recruited and assessed for clinical response to therapy. The ABSS quantitative ratings of LRTI-associated symptoms, physical signs and sputum Gram stain purulence were assessed using standard psychometric tests. RESULTS: The ABSS was evaluated among 649 cases of acute bronchitis; 129 (20%) were HIV-seropositive. The ABSS had small floor and ceiling effects (1.8/0.2) and demonstrated high internal consistency (alpha-coefficient of 0.66) and internal validity, with a mean inter item total correlation of > or =0.25. Effect sizes from baseline to subsequent follow-up visits were large (>0.5). Wheezing and chest pain were associated with higher ABSS values, whereas irrelevant clinical variables were not. CONCLUSION: The ABSS demonstrated good responsiveness, high internal consistency, good correlation with common respiratory signs and symptoms and high discriminatory validity among patients with acute bronchitis in a high HIV-seroprevalence setting.