An Unsuspected Case of Hirschsprung Disease in an Adolescent Male with Constipation

Introduction: Hirschsprung Disease, also known as Congenital Aganglionic Megacolon, is due to the absence of ganglion cells in the myenteric and submucosal plexuses of the distal colon. This rare disease occurs in 1:10,000 births and diagnosis is made in 95% of cases before 1 year. That leaves less than 5% of cases seen in patients over one year, and even less so in adolescence and adulthood.

Case Description: A 15-year-old male with a medical history of recurrent constipation presented to the emergency department with complaints of constipation and crampy abdominal pain for 6 days. Prior to his arrival, he was seen at a nearby hospital where he was found to have fecal impaction of the rectosigmoid colon on CT scan of abdomen. He underwent attempts for manual fecal disimpaction which were unsuccessful resulting in transfer of care. At home, the patient was treating his symptoms with MiraLax three times a day, one rectal enema, and one dose of magnesium citrate with no significant relief. The patient reported a high-fiber diet with good fluid intake.
On the physical exam, his abdomen was non-tender with significant fullness in the left lower quadrant and hypoactive bowel sounds throughout. He was found to be anemic with Hgb of 10.6, elevated sedimentation rate at 27, and positive fecal occult blood.
A multidisciplinary approach including pediatric gastroenterology and surgery was pursued. Lab work to rule out differentials such as Crohn's disease, Cystic Fibrosis, Celiac disease, Hirschsprung disease, and irritable bowel syndrome were all negative. The patient then underwent a full bowel clean-out in preparation for a rectal biopsy. The rectal biopsies from the mucosa, submucosa, and muscularis propria were found to be aganglionic which correlated with Hirschsprung disease.

Discussion: In young children who commonly present with delayed passage of meconium beyond the first 24 hours or with a distal intestinal obstruction, the diagnosis is clear. This is largely due to the lack of peristalsis causing a functional obstruction. However, in older children and adolescence, the disease may present as chronic constipation, and it may be difficult to discern between this and other more common causes.

Conclusion: This case illustrates the prompt diagnosis of an uncommon presentation of Hirschsprung Disease in an older pediatric patient. Although this disease normally presents in young children, there is still some prevalence in adolescence that requires further investigation. Therefore, it is beneficial to further investigate a common symptom like constipation in older children who are resistant to conservative management. Because Hirschsprung Disease is complex, creating a database of patients with information about genetic mutations, pathological findings, and clinical outcomes will be instrumental in furthering our understanding of this disease and optimizing our current therapeutic strategies.