A 6-week-old girl is brought to the office due to blood in the stool for the past week. The patient was born at 36 weeks gestation by spontaneous vaginal delivery and has been exclusively breastfed. Her stools had been soft but have become loose with streaks of blood and mucus. The patient has not had any fever, vomiting, or sick contacts. Weight is at the 25th percentile and has increased since her 1-month checkup. Temperature is 37 C (98.6 F), pulse is 135/min, and respirations are 30/min. Examination shows a playful and well-appearing infant. Cardiopulmonary examination is normal. The abdomen is soft. No anal fissure is present on rectal examination. A fecal occult blood test is positive. Which of the following is the best next step in management of this patient?

Question

A 6-week-old girl is brought to the office due to blood in the stool for the past week.  The patient was born at 36 weeks gestation by spontaneous vaginal delivery and has been exclusively breastfed.  Her stools had been soft but have become loose with streaks of blood and mucus.  The patient has not had any fever, vomiting, or sick contacts.  Weight is at the 25th percentile and has increased since her 1-month checkup.  Temperature is 37 C (98.6 F), pulse is 135/min, and respirations are 30/min.  Examination shows a playful and well-appearing infant.  Cardiopulmonary examination is normal.  The abdomen is soft.  No anal fissure is present on rectal examination.  A fecal occult blood test is positive.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d5f9_3a68_bc81_610bb79d2d4e_MD0003_00 Blood-streaked stools in a well-appearing infant age <6 months are most commonly due to anal fissure or food protein-induced allergic proctocolitis (FPIAP). In this case, a normal rectal examination, history of loose stools (as opposed to constipation), and presence of mucus in the stool make FPIAP the most likely diagnosis. FPIAP is a non-IgE-mediated reaction to a protein (usually cow's milk) in breast milk (due to maternal dairy intake) or formula. Symptoms usually develop weeks to months after initial exposure to the offending protein, and patients typically are gaining weight appropriately and have no pain. The diagnosis is made clinically and confirmed by symptom resolution after the offending protein is removed. Most breastfed infants respond to maternal elimination of dairy alone, and additional eliminations (eg, soy) usually are recommended only for persistent symptoms to avoid a severely restricted maternal diet. For formula-fed infants, switching to an extensively hydrolyzed formula, which contains predigested cow's milk proteins and is free of potentially cross-reacting soy proteins, is ideal. In rare cases of persistent bleeding, an amino acid-based (elemental) formula may be required. Symptoms typically resolve in days to weeks. (Choice B) Stool cultures may be considered for bloody diarrhea due to a suspected infectious gastroenteritis, but other symptoms (eg, fever, vomiting) would be expected. (Choice C) Abdominal x-ray is the next step in management for suspected intestinal obstruction (eg, malrotation with midgut volvulus) or necrotizing enterocolitis, both of which can cause hematochezia due to progressive intestinal ischemia. However, patients typically appear ill and have an acutely tender and distended abdomen. (Choice D) Air contrast enema is diagnostic and therapeutic for intussusception, which classically presents at age 6-36 months with intermittent, colicky abdominal pain (or fussiness in an infant) and vomiting in addition to currant jelly stools. This patient's age and lack of irritability/pain make this diagnosis unlikely. (Choice E) A Meckel diverticulum (remnant of the fetal vitelline duct) containing ectopic gastric tissue can secrete hydrochloric acid and lead to intestinal ulceration and bleeding. Although painless, bloody stools are classic in older children, symptoms at age <6 months are exceedingly rare and usually are related to associated complications, such as intestinal obstruction causing ill appearance, vomiting, and abdominal distension. Educational objective: Food protein-induced allergic proctocolitis should be suspected in a well-appearing infant with painless, bloody stools. Diagnosis is clinical, and management involves eliminating dairy from the maternal diet (if breastfeeding) or switching to an extensively hydrolyzed formula. References: Food protein-induced enterocolitis syndrome and allergic proctocolitis. (http://www.ncbi.nlm.nih.gov/pubmed/25976434) Non-IgE-mediated gastrointestinal food allergy. (http://www.ncbi.nlm.nih.gov/pubmed/25956013)

A 6-Week-Old Girl Is Brought to the Office Due to Blood