Latent Tuberculosis Infection Diagnostic and Treatment Cascade among Contacts in Primary Health Care in a City of Sao Paulo State, Brazil: Cross-Sectional Study

BACKGROUND: Diagnosis and treatment of latent tuberculosis infection (LTBI) is a tool for global TB control, especially in close contacts. But data is scarce in high burden countries, under field conditions, including data on the benefits of LTBI management. OBJECTIVE: To analyze the LTBI diagnosis and treatment cascade among contacts in primary health care (PHC) services in São José do Rio Preto—SP, Brazil. METHODS: Cross-sectional design, conducted with contacts of pulmonary TB patients followed in all PHC services. Data was collected from May to September 2014 in the Reporting System for TB cases (TBWEB) and Reporting System for Chemoprophylaxis. Medical records and treatment follow-up forms were reviewed and all the nurses responsible for TB in PHC services were interviewed. RESULTS: Among 336 contacts included, 267 (79.4%) were screened for TB or LTBI, according to the presence or not of respiratory symptoms. Among those contacts screened, 140 (52.4%) were symptomatic, 9 (3.4%) had TB disease, 106/221 (48%) had positive TST result, meeting the criteria for LTBI treatment, and 64/106 (60.4%) actually started it. Overall, among 267 screened, only 64 (24%) started LTBI treatment. The completion rates of treatment among the contacts who started it, those with positive TST result and those screened were 56.3% (36/64), 16.3% (36/221) and 13.5% (36/267), respectively. Nurses claimed that asymptomatic TB contacts pay no attention to preventive health care and do not seek medical care as they do not have symptoms of the disease. In reviewing the medical records, high proportions of contacts without evaluation, incomplete assessment, incorrect records of contraindication for LTBI treatment, lack of notes regarding the identification and evaluation of contacts were identified. CONCLUSIONS: There is a need for better organization of the surveillance and investigation routine for contacts in PHC, considering the reorganization of the work process and the features of the local health system.