A 3-year-old with buttock pain

A review of the child's history reveals that he was delivered via emergent cesarean section for maternal preeclampsia at 29 weeks, and was diagnosed as a borderline-intrauterine growth-retarded premature infant. He had a one-month neonatal intensive care unit stay but never required intubation or diuretics. He had no known residual complications of his prematurity. There was no report of delay in passing meconium, and the stooling pattern was normal during his hospitalization. He was circumcised.

At three years of age he presented to the emergency department with "butt and penis pain." His parents reported that he had a gradual decrease in frequency of stools, increased straining to stool, and development of small, hard "balls" of stool. The child was diagnosed with constipation and prescribed a regimen of prune juice, four ounces once or twice a day, as needed. Penile pain was thought to be secondary to contact dermatitis, causing mild erythema around the urethral meatus. After multiple attempts at catheterization, a urinalysis showed a pH of 5.5, 4+ protein, large hemoglobin, negative leukocyte esterase, negative nitrite, 20 to 25 RBC (red blood cell count), 3 to 5 WBC (white blood cell), 0 to 1 granular casts, few crystals, and few bacteria. There was no explanation for 4+ protein in the patient's chart. A urine culture was negative. No repeat urinalysis was sent at this visit.

Since that initial emergency department visit, the child has been seen twice. His stooling pattern improved with interventions, but after discontinuation of treatments he becomes symptomatic again with decreased stooling, increased straining, and intermittent, diffuse, crampy pain in the abdomen. His therapy has been intensified from prune juice to Senokot, and glycerine suppositories to lactulose and docusate daily. His diet remains deficient in fiber as well.

Review of systems remains negative for fever, weight loss, rash, joint pain, encopresis, hematuria, melena, hematochezia, dysuria, hematurias, oliguria, or polyuria. Parents were specifically asked if they felt there was any possible chance that he may have been abused, if he had said anything that would make them suspicious of abuse, and if he was in the care of anyone for extended periods of time that would cause them to worry about abuse. The parents expressed no concern about sexual abuse. He has continued to be small for weight and height, but has actually shown improved growth velocity since the initial visit. His exam has remained unremarkable, including normal blood pressure and a benign abdomen without palpable stool or tenderness. His hematuria resolved, but he has had intermittent mild proteinuria and sterile pyuria without casts or crystals on repeat urinalyses.

Normal stools but still 'butt pain'

Two weeks ago, the child's mother phoned to report that her son's symptoms continued. She was given a refill for the lactulose and docusate and she was referred to a pediatric gastroenterologist. The child and his parents return today because of the continued pain. The parents are most concerned about the child complaining of "butt pain." The child and his parents are unable to elaborate about the specific location of the pain other than it is from "inside" his rectum. The pain lasts seconds to minutes, causes him to stop his current activity, and he kicks and fusses a great deal with the episodes. The pain is associated with stooling or flatulence, and resolves quickly thereafter. No other alleviating or aggravating factors are known. He was toilet trained, but his parents have chosen to return to diapers while on the stool softeners because his stooling is too unpredictable. Family history is unremarkable for any gastroenterology disorders and only positive for a grandfather with a recent history of nephrolithiasis.

The physical exam reveals a young boy in no acute distress, whose weight and height parameters are in the tenth percentile, with improved growth velocity from the prior parameters of <5%. His abdominal exam is unremarkable, and there is no tenderness and no palpable stool. Rectal exam revealed no fissures or skin breakdown, normal rectal tone, no significant amount of stool in the rectal vault, and a negative guaiac test. The remainder of the exam is normal.