Left anteromedial strangulated congenital diaphragmatic hernia in an 11-year-old child: a case report

Introduction

Congenital diaphragmatic hernia (CDH) was first described by Riverius in 1679. ¹ It consists of herniation of abdominal contents of a variable extent into the thoracic cavity. Embryological defects in the diaphragm during intrauterine life are thought to be the underlying cause. The reported incidence is 1:2000 to 1:5000 live births with no gender preference. ² It usually presents immediately in the newborn period with severe respiratory distress. CDH is more commonly seen on the left side as the right pleuroperitoneal canal closes earlier and the presence of the liver is also thought to block the right side partially. ³ Malrotation of the gut and pulmonary hypoplasia are the most commonly described associated anomalies. ⁴ CDH may rarely present late in early childhood and adulthood with atypical symptoms; this often leads to misdiagnosis and delay in corrective measures. The prognosis is, however, excellent when CDH presents beyond the neonatal period. ⁵ Nonetheless, complications such as gastric strangulation, gut ischemia with perforation and shock may occur and prove fatal.

Case report

A previously healthy 11-year-old girl presented as a paediatric emergency with bilious vomiting, abdominal distension and pain with constipation. Vital signs on examination were normal. The abdomen was found to be distended and bowel sounds were increased. No air entry was heard in the left hemi-thorax and heart sounds were audible on right. A chest radiograph showed a large thoracic fluid level on the left side with a marked mediastinal shift (Figure 1). Ultrasound scan demonstrated dilated loops of gut and free fluid in the pelvic cavity and, similarly, the presence of dilated intestine in the left hemi-thorax with a small pleural effusion. Nasogastric aspiration was commenced to decompress the dilated bowel and intravenous fluid rehydration instituted. A full blood count and renal function tests were within normal limits. Contrast computed tomography (CT) of the chest confirmed the diagnosis of CDH and demonstrated underlying lung collapse (Figure 2). OPEN IN VIEWER

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Figure 2.

CT showing dilated gut loops in thoracic cavity.

Laparotomy was performed through a left sub costal incision. The liver, spleen and gastro-oesophageal junction along with the stomach were present in the abdomen cavity. Through an anteromedial diaphragmatic defect of approximately 3 cm in size, the ileum had herniated into the left thoracic cavity. Reduction of the dilated herniated ileum was impossible owing to the small size of diaphragmatic defect, which was thus extended by a lateral incision (Figure 3). Non-viable dilated bowel was then reduced into the abdomen and resected with an iliocolic anastomosis. The underlying collapsed lung was noted. Once the diaphragmatic defect was closed the abdomen could also be closed. No intercostal chest tube was placed. Postoperative recovery was uneventful. A repeat chest radiograph showed significant lung expansion after one week (Figure 4). OPEN IN VIEWER

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Figure 4.

X-ray chest showing significant lung expansion on left thoracic cavity seven days after surgery.

Discussion

Congenital diaphragmatic hernia presenting beyond neonatal age is a very rare clinical entity with an estimated incidence of 10–25% of all reported cases. ⁶ Kirkland described the first case of late presentation in 1959. ⁷ Development of the diaphragm takes place during weeks 4–8 of gestation. The central tendon formation occurs from the transverse septum and the peripheral muscular part develops from the postero-lateral pleuro-peritoneal membranes. Diaphragmatic anomalies result from either fusion defects of pleuroperitoneal membrane or from a defect in development of the muscular part. ⁸ The most common site for CDH is the postero-lateral Bochdalek hernia (78–90%), followed by the oesophageal hiatus hernia (14–24%) and then retrosternal type of herniation through the foramen of Morgagni (1.5–6%). ³ Late presentations of CDH are principally of postero-lateral type. ³ After a wide search of the literature, we failed to find a report of herniation through an antero-medial diaphragm defect.

Late presentation is often varied with atypical symptoms depending upon the extent of the herniation. Recurrent cough, dyspnoea, chest infections, vomiting and epigastric fullness are the most common symptoms. If the defect is of very small size, a patient may remain asymptomatic. Increased intra-abdominal pressure brought on by coughing, intestinal obstruction, sneezing, pregnancy or blunt abdominal trauma may precipitate herniation. Late presenting CDH may be confounded with pleural effusion, empyema, haemo-pneumothorax or even with pulmonary tuberculosis. Thus the correct diagnosis may be delayed. Dangerous insertion of intercostal drain may even be contemplated. ¹⁰

Chest radiography with a nasogastric tube in situ is helpful in making the diagnosis. This simple investigation may show the absence of the fundic gas bubble, a mediastinal shift and the presence gut loops or stomach with its nasogastric tube in the thorax. ¹⁰ Ultrasound scan may reveal peristaling gut in the thorax and may also detect other congenital malformations. In doubtful cases, contrast-enhanced CT scan is confirmative by showing the exact morphological details of the site and extent of visceral herniation. It will also confirm the anatomical position of the duodenojejunal flexure and rule out malrotation of the gut.

After confirming the diagnosis, early surgical intervention is necessary to prevent life-threatening complications of CDH. Repair may be performed effectively through abdominal and transthoracic approaches. The former is preferred where complications such as peritonitis and strangulation of gut have ensued, in order that the entire peritoneal cavity may be visualized. Abdominal contents are repositioned and repaired (if necessary) and the diaphragmatic defect is closed, usually primary. Associated anomalies may occur in 8–80% of the patients with malrotation of gut and pulmonary hypoplasia is the commonest.^11,12 Malrotation is more commonly associated with left-sided hernias. Herniation of the large intestine, small intestine and spleen may occur on the left; and of the liver, small intestine and large intestine on the right. These anomalies increase the morbidity and mortality, so should be identified before or, at least, during surgery. Late-presenting CDH usually has a good outcome in comparison to presentation as neonate. However, previously undiagnosed CDH may cause conundra if presenting first time in the context of trauma.