Are annual blood tests in preschool cystic fibrosis patients worthwhile?

AIM To investigate whether routine annual assessment blood tests in cystic fibrosis (CF) patients under 5 years influence management. METHODS Retrospective review of the results of the first annual assessment blood tests of patients with CF less than 5 years of age during a four year period (1995-99). Management changes were identified from a follow up letter to the general practitioner or local paediatrician. RESULTS A total of 169 patients (100 female), median age 2.2 years (range 0.3-4.9) were identified. Venepuncture was successful in 93% of patients. Of the 32 individual blood parameters measured, the overall success rate in obtaining a result was 81%. Eleven per cent of patients underwent subsequent management changes, including liver ultrasound, fasting glucose, and a short course of iron. Of particular importance, vitamin A and E concentrations were low in 9% of patients, which prompted an increase in prescribed dose. CONCLUSIONS These results support the recommendations for routine blood tests at annual review in preschool CF children. The results may help to rationalise which tests are performed and thus reduce laboratory costs.