A 4-day-old infant is brought to the emergency department due to bilious vomiting. The boy was born at 38 weeks gestation via an uncomplicated spontaneous vaginal delivery. His birth weight was 3.4 kg (7.5 lb), and Apgar scores were 8 and 9 at 1 and 5 minutes, respectively. The patient's hospital course was uncomplicated, and he was sent home on day 2 of life. Since discharge, he has been nursing every 2-3 hours but has begun to appear uncomfortable after feeding. Today, he developed 2 episodes of bile-stained vomiting after feeding. He has had no stool since discharge. Vital signs are normal. The infant appears irritable. There is moderate abdominal distension, and the anal canal is tight. Abdominal radiographs reveal dilated loops of bowel and air-fluid levels with no evidence of pneumatosis. Which of the following is the best next step in management of this patient?

Question

A 4-day-old infant is brought to the emergency department due to bilious vomiting.  The boy was born at 38 weeks gestation via an uncomplicated spontaneous vaginal delivery.  His birth weight was 3.4 kg (7.5 lb), and Apgar scores were 8 and 9 at 1 and 5 minutes, respectively.  The patient's hospital course was uncomplicated, and he was sent home on day 2 of life.  Since discharge, he has been nursing every 2-3 hours but has begun to appear uncomfortable after feeding.  Today, he developed 2 episodes of bile-stained vomiting after feeding.  He has had no stool since discharge.  Vital signs are normal.  The infant appears irritable.  There is moderate abdominal distension, and the anal canal is tight.  Abdominal radiographs reveal dilated loops of bowel and air-fluid levels with no evidence of pneumatosis.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d67f_a872_bc81_b7b7d3f0d65b_MD0003_00 This neonate has bilious vomiting, abdominal distension, and dilated loops of bowel consistent with intestinal obstruction. With a tight anal canal, this patient most likely has Hirschsprung disease (HD), a disorder in which a segment of colon (eg, rectosigmoid) lacks ganglion cells and therefore cannot relax. Disease severity correlates with the length of nonfunctional colon, and in some cases, those with a very short aganglionic segment may remain undiagnosed with chronic constipation for years. The most common presentation is in neonates with poor feeding, decreased stooling, and signs of bowel obstruction (eg, bilious emesis, abdominal distension). Although absence of stool in the first 48 hours of life is classic, passage of meconium does not exclude HD. Increased rectal tone is typical, and expulsion of gas and stool ("squirt sign") may occur on digital rectal examination due to temporary relief of the obstruction. neonates The first step in evaluation of intestinal obstruction is abdominal x-ray, which shows dilated bowel loops and absent gas in the rectum. Once perforation is excluded (ie, no free air on x-ray), contrast enema should be performed to determine the level of obstruction and differentiate HD from other etiologies (eg, meconium ileus). A transition zone between the dilated proximal colon (megacolon) and the narrow, aganglionic sigmoid colon is characteristic of HD. Diagnosis is confirmed by absent ganglia on suction rectal biopsy. transition zone (Choice A) Abdominal ultrasound is helpful in evaluating obstruction due to intussusception, which presents at age 6-36 months with intermittent abdominal pain and vomiting. This patient's age, lack of episodic symptoms, and increased rectal tone make intussusception unlikely. (Choices C and F) Upper GI series is the next step for assessing malrotation, which presents with intestinal obstruction but does not cause a tight anal canal. Abdominal CT scan may also identify malrotation but is typically avoided due to radiation and decreased sensitivity. (Choice D) Emergency laparotomy is indicated for clinical or radiographic evidence of intestinal perforation (eg, rigid abdomen, unstable vital signs, free air under the diaphragm). (Choice E) Constipation can occur with congenital hypothyroidism but is unlikely to result in intestinal obstruction. In addition, anal sphincter tone would not be increased. Educational objective: Hirschsprung disease typically presents in neonates with decreased stooling, increased rectal tone, and signs of intestinal obstruction (eg, bilious emesis, abdominal distension, dilated bowel loops). Contrast enema is performed to identify the level of obstruction. References: Hirschsprung disease. (http://www.ncbi.nlm.nih.gov/pubmed/23615177)

A 4-Day-Old Infant Is Brought to the Emergency Department Due