LONG-TERM PULMONARY AND ALLERGIC OUTCOME OF VERY-LOW-BIRTH-WEIGHT PREMATURES WITH AND WITHOUT BRONCHOPULMONARY DYSPLASIA

Fifty sex children with a birth weight of less than 1500 g and gestational age less than 34 weeks were studied at a mean age of 7.7 years. All had required mechanical ventilation, 36 suffered from hyaline membrane disease, 17 from atelectasis and three from pneumonia. Of these patients 37 developed broncho-pulmonary dysplasia (BPD). The study included skin prick test, measurement of ciliary beat frequency, chest X-ray, whole-body plethysmography and histamine challenge. Eight patients suffered from recurrent pulmonary infections up to the age of 4 years. Eleven children had a positive skin prick test. Three suffered from allergic asthma and six from hay-fever. The family history of atopy in these premature infants was no different from that of the general population. Ciliary beat frequency was normal in all cases (frequency: 11.8 +/- 1.8 Hz). In 34 patients X-rays showed minimal changes (peribronchial thickening n = 6, mild emphysema n = 28). Pulmonary function was normal except for an increase of thoracic gas volume which was correlated to grade of BPD according to Northway. There was a significant correlation between oxygen-score and rediological stage of BPD (r = 0.7). Histamine challenge showed hyperresponsiveness in 53% of the children. Eight patients showed a threshold similar of mild asthma (< 1000-mu-g histamine per ml). The degree of airway hyperreactivity was correlated to the grade of BPD (r = 0.7; p < 0.01) and the oxygen-score (r = -0.63; p < 0.05). The oxygen-score may be considered a predictor of hyperresponsiveness and pulmonary outcome in later childhood.