[Congenital diaphragmatic hernia in older children].
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The incidence of congenital diaphragmatic hernia (CDH) is about 4.8/10,000 live births. Its typical clinical presentation is respiratory distress occurring immediately after birth or in the first few hours or days of a child's life. It is characterized by a high mortality rate. Exceptionally, CDH can occur at an older age, its symptoms then frequently reflecting gastrointestinal obstruction or mild respiratory symptoms. In such cases CDH presents a far more complex diagnostic problem. The paper presents the cases of two girls without typical symptomatology, aged 5.5 and 10 years, in whom CDH was detected incidentally upon thorough physical examination and chest x-rays. Further radiographic evaluation, which included barium contrast study and spiral computed tomography, confirmed the suspicion of a left-sided posterolateral diaphragmatic hernia with associated intestinal malrotation. Surgical intervention conclusively confirmed a diaphragmatic defect at the site of Bochdalek's foramen in both cases. The vital capacity of the older girl, which was low before the surgery (VC 1.66 L; 69% of predicted), was significantly increased a month after the surgical treatment (VC 2.25 L; 92% of predicted). The generally expressed view that the clinical onset of CDH is rare after the neonatal period seems to be erroneous. Some papers report on the clinical presentation of CDH after the neonatal period in as many as 13%-14% of infants and young children suffering from CDH. Infants and young children with a delayed clinical occurrence of CDH can present with respiratory or gastrointestinal symptomatology. Children presenting with gastrointestinal symptoms have been shown to be significantly older than those presenting with respiratory symptoms. In older children and adolescents, the symptoms and signs of CDH, which include acute hernial incarceration, nausea, recurrent vomiting, diarrhea, obstipation, acute gastric dilatation, subcostal pain, failure to thrive and recurrent chest infections, habitually present a significant diagnostic problem. Diagnostic errors are mainly due to the fact that the possibility of CDH in that age is totally neglected. The most recurrent diagnostic misinterpretations in such cases are pneumonia or massive pleuropneumonia, empyema, pneumothorax, lung cysts and bullae, and gastric volvulus. Thus, whenever a child presents with uncommon respiratory or gastrointestinal symptoms and an anomalous chest x-ray, a differential diagnosis of CDH should be considered. Otherwise, an accurate diagnosis in both young and older children will most probably be only reached at autopsy. In conclusion, the presented cases corroborate the finding that CDH in older children may present with scarce symptoms, mostly gastrointestinal, or may be altogether asymptomatic and unrecognized until as late as adolescence. However, when a diagnosis of CDH has been established, albeit asymptomatic, it must be promptly treated surgically in order to prevent complications, such as strangulation or bowel perforation, and thus avert a potentially fatal outcome. The size itself of the herniac foramen is unlikely to be a determining factor at the time of clinical presentation of CDH. Surgical occlusion of CDH may in older children result in an improved vital capacity, as such cases are rarely associated with major pulmonary hypoplasia. Complications resulting from surgical treatment of CDH in older children are more likely to occur in the gastrointestinal system, as a consequence of the associated bowel malrotation and inadequate bowel fixation. Finally, these two cases corroborate the diagnostic value of accurate history taking and thorough physical examination.