In a case-control study to evaluate a systematic scoring system for diagnosing pulmonary tuberculosis (PTB) in children, cases had gastric lavage cultures positive for Mycobacterium tuberculosis and recovered after anti-tuberculosis treatment, while controls had negative cultures and recovered with non-anti-tuberculosis treatment. Radiological aspect (OR = 25.39), contact with a tuberculous adult (OR = 10.67) and tuberculin skin test > or = 10 mm (OR = 8.23) were associated with PTB diagnosis. The sensitivity of the score ranged from 58% to 89% and the specificity from 98% to 86%, with cut-offs of respectively > or = 40 or > or = 30. The scoring system may be a useful diagnostic method in areas with a high prevalence of TB.