A girl, born at full term to nonconsanguineous parents with a birth weight of 3.2 kg, presented to the Emergency Department at the age of 2 days with failure to pass meconium, feeding difficulties, bilious vomiting, and abdominal distention. Laboratory data included normal ESR, haemoglobin, packed cell volume, and white blood cell and platelet counts.
A nasogastric tube was placed, parenteral nutrition and antibiotics were started via an intravenous catheter, and several diagnostic procedures were carried out.
A plain abdominal radiograph showed gaseous distention of the gut, with widened intestinal loops. Barium enema on unprepared bowel did not reveal a transitional zone or abnormal mucosal pattern, but showed a narrowed colon (Fig. 1). Anorectal manometry was not diagnostic, although the anorectal reflex was not clearly evoked.
Suction rectal biopsy showed an absence of ganglion cells in the submucosal plexus, but no submucosal nerve trucks and a normal acetylcholinesterase pattern in the lumina propria, muscularis mucosae, and submucosa (Fig. 2).
These features most likely represent:
- Transient neonatal intestinal obstruction
- Hirschsprung's disease
- Meconium ileus, meconium plug syndrome
- Small left colon syndrome
- Esophageal atresia with distal tracheoesophageal fistula
- Ileal atresia
- Necrotizing enterocolitis
Answer: Long-segment Hirschsprung's disease (total colonic aganglionosis) was suspected. Colonic washouts via a nasogastric tube were performed and surgery was carried out at the age of 8 days. Frozen sections of intraoperative seromuscular biopsies revealed the typical pattern of total colonic aganglionosis, in which the circular and the longitudinal muscle coats are closely opposed, with an absence not only of ganglion cells, but also of large nerve trunks (Fig. 3). The patient was found to have long-segment disease extending to the terminal ileum, and a one-stage ileonal pull-through was performed. Anal stenosis requiring dilatations for 6 months was the only postoperative complication.
Comment: This case emphasizes the need for careful examination of the suction rectal biopsy to identify patients with total colonic aganglionosis. Generally, in both the short-segment and long-segment diseases, the acetylcholinesterase pattern is pathognomonic of Hirschsprung's disease. However, in rare cases of total colonic aganglionosis, the changes in the biopsy may be mild with no apparent increase in the number of nerve fibers. This pattern may be interpreted as normal for a low biopsy taken immediately above the pectinate line.
In conclusion, clinicians and pathologists should be aware that total colonic aganglionosis may be difficult to diagnose because of the possibility of false negatives on barium enema, anorectal manometry, and histology. In some cases, only at surgery is it possible to confirm the diagnosis.