- Slides: 9
Radiological Category: Pediatrics Principal Modality (1): General Radiography Principal Modality (2): None Case Report #0194 Submitted by: Elaine Granmayeh, M. D. Faculty reviewer: Lawrence Robinson, M. D. Date accepted: 14 March 2005
Case History Term male infant with poor respiratory effort.
Test Your Diagnosis Which one of the following is your choice for the appropriate diagnosis? After your selection, go to next page. • Congenital cystic adenomatoid malformation (CCAM) • Pulmonary interstitial emphysema • Congenital diaphragmatic hernia • Pneumonia with pneumatoceles
Findings and Differentials Findings: Patient is intubated. Right hemithorax demonstrates a diffuse bubbly or cystic appearance with protrusion into the left hemithorax. Heart is shifted to the left. Minimal aerated lung is present along the left cardiac border. There is a small amount of bowel gas in the right upper abdominal quadrant. The lower abdomen is devoid of bowel gas. A nasogatric tube extends to the stomach, which lies in the left upper abdominal quadrant. Differentials: • Congenital diaphragmatic hernia • Congenital cystic adenomatoid malformation
Discussion The differential considerations include CCAM and congenital diaphragmatic hernia. In pulmonary interstitial emphysema, the interlobular septae demonstrate small round or discrete linear lucencies not observed in this case. Pneumatocele formation is also excluded because it occurs 10 -14 days after onset of pneumonia and would therefore not be expected at birth. CCAM is a hamartomatous lesion, which demonstrates adenomatoid proliferation of bronchial structures that form cysts and lack alveoli. Three types are described radiographically: type I presents as multiple large cysts or a single dominant cyst, type II is characterized by multiple smaller cysts, and type III appears solid but contains microscopic cysts . CCAM can be large and cause mediastinal shift, but the bowel gas pattern should be normal. While Type I CCAM should be considered in this case, there is an abnormal intestinal pattern which does not support the diagnosis. The correct diagnosis is congenital diaphragmatic hernia. The most common type of herniation occurs through a posterolateral defect of the diaphragm, known as a Bochdalek hernia. This is located on the left in 80% of cases. Morbidity is due to pulmonary and left heart hypoplasia as well as lung immaturity leading to persistent pulmonary hypertension of the newborn [2, 3].
Discussion Delayed presentation is more commonly right-sided, where the liver may temporarily prevent movement of viscera into the chest. Delayed presentation has been reported in infants with Group B streptococcal pneumonia . One case report postulates that positive pressure ventilation and abnormal lung compliance in a neonate with Group B streptococcal pneumonia contributed to delayed right diaphragmatic hernia . Anterior diaphragmatic or Morgagni hernias and central tendon defects with herniation through the central diaphragm into the pericardium are seen much less commonly .
Diagnosis Congenital diaphragmatic hernia
References 1. Giacoia GP and Jegathesen S. “Acquired” congenital diaphragmatic hernia following early onset group B streptococcal pneumonia. Clin Pediatr 1980; 19(10): 662 -663. 2. Kirks DR. Practical Pediatric Imaging Diagnostic Radiology of Infants and Children. 1998, Lippincott-Raven, Philadelphia, p. 842. 3. Kuhn J, Slovis TL, Haller JO. Caffey’s Pediatric Diagnostic Imaging. Tenth edition, Vol. 1, 2004, Elsevier Inc. , Philadelphia, pp. 58 -67.