[The neonatal respiratory insufficiency syndrome: the role of the chest radiogram].

INTRODUCTION: Chest radiography is considered the most reliable diagnostic tool to study the respiratory distress syndrome in newborns and one of the few diagnostic investigations which can be used considering the clinical situation of these patients and the need of a prompt diagnosis.

MATERIALS AND METHODS: We examined 124 newborns (56 males and 68 females) submitted to chest radiography at least once. Two radiologists analyzed the images investigating: a) chest expansion, b) reticulonodular opacities, c) aerial bronchograms, d) parenchymal consolidation, e) atelectasis, f) pneumothorax. The clinical diagnosis was made by neonatologists on the basis of clinical and instrumental data and of the clinical evolution of the patients.

RESULTS: Twenty of 23 clinically negative patients had negative chest radiographs and 3 were false positives. Transient tachypnea was diagnosed in 14 newborns where chest radiography showed reticulonodular opacities. Ten of 62 patients with hyaline membrane disease had a negative chest radiograph, 26 had fine granular opacities, 16 marked hypoexpansion with reticulonodular opacities and aerial bronchogram, and 10 diffuse parenchymal consolidations with aerial bronchogram also in the peripheral lung. Eleven patients had a clinical and radiological diagnosis of segmental or lobar atelectasis; 5 newborns had an aspiration syndrome and radiography showed parenchymal consolidations in 4 and was negative in one. Five patients had pneumothorax, 3 diaphragmatic hernia and 1 infective pneumonia; radiology confirmed the diagnosis in all cases. We had three false positives and 11 false negatives at conventional radiography--i.e., 10 had MMI and one the meconium aspiration syndrome. Diagnostic sensitivity was 89.1%, specificity 86.9% and diagnostic accuracy 88.7%.

CONCLUSIONS: Our results are partially limited by the lack of a reference gold standard. Nevertheless, if we consider the clinical condition and the respiratory distress syndrome evolution as a valid reference, the diagnostic accuracy of radiography is good.