A 52-hour-old girl is evaluated in the newborn nursery for abdominal distension. The patient was delivered at 40 weeks gestation to a 21-year-old woman by cesarean delivery for arrest of labor. Apgar scores were 8 and 9 at 1 and 5 minutes, respectively. The patient has been voiding appropriately but has not yet had a bowel movement. The abdomen is tense and distended. Rectal examination reveals no stool or release of gas. Feeds are held, and a nasogastric tube is placed successfully for decompression. Upright abdominal radiograph reveals multiple dilated loops of small bowel with paucity of air in the large intestine and rectum. The left lateral decubitus view shows free air above the liver, and an emergency laparotomy is performed. Thick, sticky stool is irrigated and evacuated from the ileum, and the colon appears diffusely narrow. This patient is at increased risk for which of the following comorbidities?

Question

A 52-hour-old girl is evaluated in the newborn nursery for abdominal distension.  The patient was delivered at 40 weeks gestation to a 21-year-old woman by cesarean delivery for arrest of labor.  Apgar scores were 8 and 9 at 1 and 5 minutes, respectively.  The patient has been voiding appropriately but has not yet had a bowel movement.  The abdomen is tense and distended.  Rectal examination reveals no stool or release of gas.  Feeds are held, and a nasogastric tube is placed successfully for decompression.  Upright abdominal radiograph reveals multiple dilated loops of small bowel with paucity of air in the large intestine and rectum.  The left lateral decubitus view shows free air above the liver, and an emergency laparotomy is performed.  Thick, sticky stool is irrigated and evacuated from the ileum, and the colon appears diffusely narrow.  This patient is at increased risk for which of the following comorbidities?

Quizplus · Accepted Answer

11ec25c8_d67a_2a29_bc81_69dd056e8873_MD0003_00 This patient's presentation is most likely due to meconium ileus, which is virtually diagnostic of cystic fibrosis (CF), with ~90% of cases of meconium ileus due to CF. A mutation in the CF transmembrane conductance regulator (CFTR) gene results in abnormal chloride transport and viscous secretions in multiple organs. Thick, inspissated meconium is difficult to propel, resulting in obstruction at the level of the ileum (ie, dilated small bowel with scant air in the colon/rectum) and a narrow, underdeveloped large intestine (microcolon). Unlike 99% of healthy newborns, patients with meconium ileus do not pass stool in the first 24 hours after birth. Abdominal distension is common, and perforation (seen as free air on x-ray) is a potentially fatal complication that requires emergency surgery. microcolon Because of thick, viscous secretions and impaired mucociliary clearance in the sinuses and respiratory tract, nearly all CF patients develop sinopulmonary disease. Chronic rhinosinusitis, a significant cause of morbidity, is often associated with nasal polyposis. Imaging reveals sinus cavity opacification due to tenacious mucus in almost all CF patients as early as age 1, and patients often require surgical debridement. (Choice A) Bicuspid aortic valve is common with Turner syndrome, which is associated with an increased risk of inflammatory bowel disease (IBD). IBD can cause intestinal strictures and obstruction but does not manifest in the newborn period. In addition, CF is not associated with a bicuspid aortic valve. (Choices C and D) Along with CF, another important differential diagnosis in newborns with delayed passaged of meconium is Hirschsprung disease (HD). HD is associated with Down syndrome, which increases the risk of early-onset Alzheimer disease and hypothyroidism. However, in contrast to the thick, sticky stool in this patient, meconium consistency is normal in patients with HD, and the typical presentation includes increased rectal tone, squirt sign (expulsion of gas/stool on rectal examination), and obstruction at the rectosigmoid region with a dilated proximal colon. Patients with CF do not have increased risk of developing Alzheimer disease or hypothyroidism. dilated proximal colon (Choice E) Sensorineural hearing loss (SNHL) is typically associated with neurofibromatosis type 2, an autosomal dominant disorder with neurologic and cutaneous, not gastrointestinal, manifestations. SNHL can develop in a minority of patients with CF due to frequent treatment with aminoglycosides for gram-negative infections (eg, Pseudomonas aeruginosa) but would not be expected in the newborn period. Educational objective: Meconium ileus is due to inspissated meconium and classically presents with delayed passage of meconium, in addition to signs of intestinal obstruction with or without perforation at the level of the ileum. Meconium ileus is virtually diagnostic for cystic fibrosis, which causes chronic sinopulmonary disease. References: Meconium ileus in cystic fibrosis. (http://www.ncbi.nlm.nih.gov/pubmed/28986020) Chronic rhinosinusitis in patients with cystic fibrosis. (http://www.ncbi.nlm.nih.gov/pubmed/27393775)

A 52-Hour-Old Girl Is Evaluated in the Newborn Nursery for Abdominal