PPD is a useful test to identify children infected with TB independently of whether they had received BCG or not. Children exposed to adults with TB are at high risk of infection. The risk of infection is associated with the intimacy of contact and the number of bacilli expectorated in sputum.

Our findings suggest that proficiency in TBLC is achieved at approximately the 70th procedure; however they need to be validated in more series and cohorts.

Tuberculosis imposes high human and economic tolls, including in Europe. This study was conducted to develop a severity assessment tool for stratifying mortality risk in pulmonary tuberculosis (PTB) patients. A derivation cohort of 681 PTB cases was retrospectively reviewed to generate a model based on multiple logistic regression analysis of prognostic variables with 6-month mortality as the outcome measure. A clinical scoring system was developed and tested against a validation cohort of 103 patients. Five risk features were selected for the prediction model: hypoxemic respiratory failure (OR 4.7, 95% CI 2.8–7.9), age ≥50 years (OR 2.9, 95% CI 1.7–4.8), bilateral lung involvement (OR 2.5, 95% CI 1.4–4.4), ≥1 significant comorbidity—HIV infection, diabetes mellitus, liver failure or cirrhosis, congestive heart failure and chronic respiratory disease–(OR 2.3, 95% CI 1.3–3.8), and hemoglobin <12 g/dL (OR 1.8, 95% CI 1.1–3.1). A tuberculosis risk assessment tool (TReAT) was developed, stratifying patients with low (score ≤2), moderate (score 3–5) and high (score ≥6) mortality risk. The mortality associated with each group was 2.9%, 22.9% and 53.9%, respectively. The model performed equally well in the validation cohort. We provide a new, easy-to-use clinical scoring system to identify PTB patients with high-mortality risk in settings with good healthcare access, helping clinicians to decide which patients are in need of closer medical care during treatment.

No abstract

The tuberculin test (PPD) is used frequently in the diagnosis of tuberculosis. PPD, however, relies on an intact cell-mediated immunity and infected children often have false negative results. This study assessed whether a single oral zinc supplement modifies the PPD induration size and its association with nutritional status in Brazilian children. Ninety-eight children below 15 years of age who had been exposed to adults with smear-positive pulmonary TB in 1998 were tested by PPD in 1998 and 2000. Children were randomised in 2000 to receive a single oral dose of zinc sulphate or a placebo at the time of administering the PPD. Forty-three (44%) children were PPD-positive in 1998 and 54 (55%) in 2000. A higher proportion of children were classified as PPD-positive in 2000 in the zinc-supplemented group (57.1%) than in the placebo group (53.1%). PPD indurations were larger in children receiving zinc (mean 18.5 and 15.5 mm in the zinc and placebo groups, respectively) (p < 0.03). Mean induration sizes in 2000 were larger in zinc-supplemented children, regardless of their nutritional status. Our study demonstrates that zinc increases the PPD induration size in children irrespective of nutritional state. Zinc supplementation could work by correcting asymptomatic or marginal zinc deficiencies or as a non-specific booster of immunological mechanisms (whether or not there is a deficiency).