Initiation of anti-tuberculosis treatment in children following gastric aspirate testing, Botswana, 2008-2012.

SETTING: Diagnosing pediatric tuberculosis (TB) is difficult; to improve diagnosis, gastric aspiration (GA) was performed in 121 Botswana health facilities. OBJECTIVE: To describe treatment initiation and outcomes in children with a positive GA result and those treated empirically. METHODS: Children with smear or culture-positive GA or those clinically diagnosed were referred for anti-tuberculosis treatment. Treatment initiation and outcomes were assessed from February 2008 to December 2012 using name-based matching algorithms of the GA database; treatment initiation was captured in the electronic TB registry. Analyses included descriptive statistics and regression models. RESULTS: GA was conducted in 1268 children. Among these, 121 (9.5%) were GA-positive; and treatment was initiated in 90 (74.3%). An additional 137 (11.9%) were treated empirically. More than a third (36.4%) had known human immunodeficiency virus status (positive or negative); this was significantly associated with TB treatment initiation (adjusted odds ratio [aOR] 1.8, 95%CI 1.3-2.5); P < 0.05). Among the 90 children with a positive GA result, nearly all either completed treatment (78.9%) or were on treatment (20.0%) at the time of data collection. CONCLUSION: We could not find documentation of treatment for more than a quarter of the children with laboratory-confirmed TB, an important gap that calls for further examination. The failure to initiate prompt treatment requires investigation and urgent action.

Risk factors for gastric aspirate culture contamination in children evaluated for tuberculosis in Botswana.

SETTING: Gastric aspirate (GA) sample culture is commonly performed in children evaluated for tuberculosis (TB) who cannot expectorate sputum. Contamination limits culture yield and negatively impacts care. OBJECTIVE: To evaluate the proportion of and factors associated with GA contamination at a central TB reference laboratory in Botswana. DESIGN: This was a 5-year cross-sectional study of untreated children aged 12 years evaluated for TB with the first GA sample registered at the National Tuberculosis Reference Laboratory. We performed descriptive statistics to assess the risk of contamination with patient age, sex, transport time and distance, culture medium, and facility type. We generated multivariable logistic regression models using generalized estimating equation extension. RESULTS: We analyzed 3642 samples. The median age was 2 years (interquartile range [IQR] 1-4), median transport time was 4 days (IQR 2-7), and 64.1% of samples were from clinics or health posts. TB culture positivity was 1.6% (60/3642), and contamination was observed in 35.6% (1298/3642). Hospital collection was associated with lower contamination risk (adjusted OR [aOR] 0.53, 95%CI 0.40-0.69) and Mycobacteria Growth Indicator Tube vs. Löwenstein-Jensen medium with higher risk (aOR 1.88, 95%CI 1.51-2.34). CONCLUSION: In routine care settings, high sample contamination and low TB culture yield were observed. This raises questions about the collection technique and storage in lower-level facilities and affirms higher risk with a liquid culture medium.

High rates of exposure to tuberculosis patients among HIV-infected health care workers in Botswana.

OBJECTIVE: To compare daily exposure to tuberculosis (TB) patients between HIV-infected and non-HIV-infected health care workers (HCWs), and examine the uptake of antiretroviral therapy (ART) and isoniazid preventive therapy (IPT) among HIV-infected HCWs in Botswana. DESIGN: We conducted a cross-sectional study among HCWs in 30 hospitals and clinics. We determined self-reported exposure frequency to TB patients and HIV status through in-person interviews. HCWs with unknown or negative HIV status were offered rapid HIV testing. Multivariable Poisson regression modeling with robust variance was used to estimate the association between HIV status and daily exposure to TB patients. RESULTS: Of 1877 participants enrolled, 1388 (73.9%) with complete data were included in this study. Among 277 (20.0%) HIV-infected participants, 14.3% were newly diagnosed, 57.8% were on ART, and 34.3% reported previously receiving IPT. Daily exposure to TB patients was reported by respectively 48.4% and 52.9% of HIV-infected and non-infected participants. After adjusting for sex, age, occupation, and department, the rates of daily TB exposure remained similar between HIV-infected and non-HIV-infected participants (prevalence ratio 0.96, 95%CI 0.85-1.08). CONCLUSIONS: We found similar rates of exposure to TB patients between HIV-infected and non-HIV-infected HCWs. Improved efforts are needed to reduce nosocomial exposure to TB among HIV-infected HCWs.

Diagnosis of paediatric tuberculosis using sputum induction in Botswana: programme description and findings.

SETTING: Four public hospitals in Botswana, a high tuberculosis (TB) burden setting. OBJECTIVES: To assess the feasibility and utility of sputum induction in the diagnosis of paediatric TB. DESIGN: From 2008 to 2010, children aged ≤18 years referred for suspected pulmonary TB underwent sputum induction. Confirmed TB was defined as the presence of at least one of the signs and symptoms suggestive of TB and positive Mycobacterium tuberculosis culture. Information on TB-associated symptoms (cough, fatigue, night sweats, low appetite, chest pain, weight loss, haemoptysis and contact with a TB case) was collected for three risk groups: human immunodeficiency virus (HIV) positive children, HIV-negative children aged <3 years and HIV-negative children aged ≥3 years. RESULTS: The median age of the 1394 subjects who underwent sputum induction was 3.8 years (IQR 1.3-8.4); 373 (27%) were HIV-positive, 419 (30%) were HIV-negative and 602 (43%) had unknown HIV status. TB was confirmed in 84 (6.0%); cases were more likely to have weight loss, chest pain or TB household contacts. There were no serious complications attributable to sputum induction during and after the procedure; only 0.8% (9/1174) of patients reported minor complications. CONCLUSIONS: In Botswana, paediatric sputum induction was feasible, safe and assisted bacteriological confirmation in a subgroup of children treated for TB.

Yield of contact tracing from pediatric tuberculosis index cases in Gaborone, Botswana.

SETTING: Contact tracing using pediatric index cases has not been adequately investigated in high tuberculosis (TB) and human immunodeficiency virus (HIV) prevalence settings. OBJECTIVE: To determine the yield of contact tracing in household contacts of pediatric TB index cases in Botswana. DESIGN: Index cases included all pediatric (age ≤ 13 years) TB admissions from January 2009 to December 2011 to Botswana's largest referral hospital. A contact tracing team identified cases, conducted home visits, symptom-screened contacts and referred those with ≥ 1 TB symptoms. The primary outcome was newly diagnosed TB in a contact. RESULTS: From 163 pediatric index cases, 548 contacts were screened (median 3 contacts/case, interquartile range [IQR] 2-4). Of these, 49 (9%) were referred for positive symptoms on screening and 27/49 (55%) were evaluated for active TB. Twelve new TB cases were diagnosed (12/548, 2.2%); the median age was 31 years (IQR 23-38); 11 (92%) were smear-positive. Ten (83%) had known HIV status: 7 (70%) were HIV-positive. To find one new TB case, the number needed to contact trace (index cases/new cases) was 13.6, and the number needed to screen (contacts/new cases) was 46. CONCLUSION: This yield of contact tracing using pediatric index cases is similar to the traditional adult index case approach. Improving the proportion of symptomatic contacts evaluated may increase yield.