[Contact investigation according to concentric circles in a case of laryngeal tuberculosis].

OBJECTIVE

To describe the census and contact investigation in a case of laryngeal tuberculosis.

METHODS

Based on a patient with laryngeal tuberculosis and through interviews and ocular inspection, we established three circles of contacts. The tuberculin test was performed (positive ≥5 mm). Persons testing positive were invited to undergo a chest x-ray. The association of the infection was calculated with the odds ratio. The exposure-response relationship was determined with the linear trend χ2 test.

RESULTS

The overall prevalence of infection was 39.9% (67/168). The prevalence among coworkers was 60.0% (24/40), that among frequenters of the town bar was 43.3% (13/30) and the conversions rate was 12.9%. There was a relationship with the degree of exposure (p <0.0001).

CONCLUSIONS

Laryngeal tuberculosis involved high transmission to coworkers and frequenters of the town bar. In-depth studies through concentric circles and good communication with exposed individuals should be carried out.