Erythrocyte sedimentation rate in childhood tuberculosis: is it still worthwhile?

OBJECTIVE: To evaluate the utility of the erythrocyte sedimentation rate (ESR) in the diagnosis of childhood tuberculosis.
DESIGN: Data were collected retrospectively from the Qatar National Tuberculosis (TB) Registry for children (birth to 14 years of age) from 1983 to 1996. The diagnosis of active tuberculosis was based on positive sputum cultures (or histology) or an abnormal chest radiograph that responded to anti-tuberculosis chemotherapy.
RESULTS: Of 144 childhood TB patients, 68 (47%) had an ESR documented at the time of diagnosis. Twenty-two children (33%) had a normal ESR (<10 mm/hour) and 46 children (67%) had an elevated ESR (> or =10 mm/hour) at the time of diagnosis. Culture positive and symptomatic children had significantly higher ESR values than culture negative and asymptomatic children, respectively, at the time of diagnosis. There was no significant difference in ESR values for children with extrapulmonary versus pulmonary disease, and likewise no significant correlation between either age or size of tuberculin skin test reactivity and ESR values.
CONCLUSION: Although an elevated ESR may be expected in children with tuberculosis, this study found that one-third of children with TB had a normal ESR at the time of diagnosis, and consequently there would seem to be little value in using ESR as a diagnostic test for childhood tuberculosis.