| Symptoms or history | Possible implications |
| Acute signs | |
| Delayed passage of meconium (after 48 hours of life) | Possible HD, other anatomical intestinal obstruction, or CF, but may be normal if infant is otherwise asymptomatic |
| Severe abdominal distension | HD (in an infant), functional ileus (ill patient), other cause of obstruction, or CF |
| Fever, vomiting, or diarrhea | HD-associated enterocolitis |
| Rectal bleeding | Anal fissure, food protein-induced proctitis (milk protein intolerance), IBD, infectious colitis, HD-associated enterocolitis |
| Chronic signs | |
| Constipation present from birth or early infancy | HD, intestinal neuronal dysplasia, pseudo-obstruction, congenital anorectal malformations, or other congenital cause of constipation |
| Ribbon stools (very narrow in diameter) | HD or anal stenosis/congenital anorectal malformation |
| Urinary incontinence or bladder disease | Congenital or acquired neurologic deficit (eg, sacral teratoma), CAKUT (which may be associated with HD), or pseudo-obstruction |
| Weight loss or poor weight gain | Any organic cause, including HD, celiac disease, and CF |
| Delayed growth (eg, decreasing height percentiles) | Any cause, especially hypothyroidism |
| Extraintestinal symptoms (especially neurologic deficits) | Implications depend on the symptom; may include syndromes associated with HD (eg, Down syndrome) |
| Family history of MEN or associated neoplasms (medullary thyroid cancer, pheochromocytoma, or hyperparathyroidism) | MEN type 2A (associated with HD) or type 2B (associated with intestinal ganglioneuromas) |
| Physical findings | Possible implications |
| Severe abdominal distension | HD (in an infant), functional ileus (ill patient), pseudo-obstruction, or other cause of obstruction |
| Pelvic mass | Sacral teratoma |
| Lower spine abnormalities | Spinal dysraphism, sacral agenesis |
| Lumbosacral dimple, hair tuft or lipoma, or deviation of the gluteal cleft | Spinal dysraphism |
| Anal scars | Anal fissures or trauma |
| Anteriorly displaced anus | Anorectal malformation |
| Patulous anus | Neurologic dysfunction (eg, spinal dysraphism) |
| Perianal fistula | Anorectal malformation |
| Tight anal canal with narrow rectum | HD |
| Explosive expulsion of stool after digital examination of the rectum | HD |
| Absent anal wink | Spinal cord anomalies |
| Absent cremasteric reflex | Spinal cord anomalies |
| Decreased lower extremity tone or strength | Spinal cord anomalies |
| Abnormal lower extremity deep tendon reflex: absence of delay in relaxation phase | Spinal cord anomalies, hypothyroidism |
| Abnormal thyroid gland | Hypothyroidism |
| Extreme fear during the anal inspection | Sexual abuse |
