GI Flashcards
What workup should be done for a neonate that passes bloody meconium?
Hematemesis and melena are not uncommon in the neonatal period, especially if gross placental bleeding has occurred at the time of delivery. The diagnostic procedure that should be done first is the Apt-Downey test, which differentiates fetal from adult hemoglobin in a bloody specimen. The test is based upon the finding that fetal hemoglobin is alkali resistant, while adult hemoglobin will convert to hematin upon exposure to alkali. If the blood in an affected infant’s gastric contents or stool is maternal in origin, further workup of the infant is obviated.
How is necrotizing enterocolitis managed?
Management depends initially on the presence or absence of perforation; if no evidence of free peritoneal air is found, the infant should be put on bowel rest with nasogastric decompression, and systemic
antibiotics are initiated. Electrolytes and vital signs should be monitored closely, and serial abdominal films should be performed to evaluate for perforation. If free air is identified on plain radiographs or if the infant clinically worsens with medical management, surgical consultation is required. An exploratory laparotomy is usually performed, and any necrotic intestinal tissue is removed.
What is meconium ileus pathognomonic for?
CF -Approximately 15% of children with CF will present with meconium ileus
What is meconium ileus?
Seen in CF. In meconium ileus, low or distal intestinal obstruction results from the impaction of thick, tenacious meconium in the distal small bowel. Radiographs show dilated loops of bowel, and usually reveal a bubbly or granular pattern at the level of obstruction. The enema shows microcolon from disuse.
Positive p-ANCA is a sign of what GI disease?
Ulcerative colitis (positive in 70% of cases)
Positive anti-Saccharomyces cerevisiae antibodies (ASCA) is a sign of what GI disease?
Crohn’s disease (positive in 55% of cases)
What is the classic presentation of intussusception?
Infant between 4-10 months with sudden onset of intermittent colicky abdominal pain (infant irritable then abates, then comes back with increasing frequency). Can lead to vomiting and obtundation. Infants may also get currant jelly stool, and a sausage-shaped mass may be felt in the RUQ.
What imaging study is suggested for suspected intussusception?
An air, barium, or saline enema under fluoroscopic or ultrasound control can be therapeutic as well as diagnostic when the hydrostatic effects of the contrast serve to reduce the intussusception, but should be performed with surgical backup, as a
complication of attempted reduction is intestinal perforation. Rates of intestinal perforation are lowest with air reduction.
What is Sandifer syndrome?
The bending or arching of the neck caused by gastroesophageal reflux; this condition may be confused with infantile spasm.
What is the typical presentation of a Meckel diverticulum if symptomatic?
Painless rectal bleeding in the first 2 years of life.
How can lactose intolerance be diagnosed?
Removal of the offending sugar, with a reproduction of symptoms upon reintroduction or a hydrogen breath test (more specific - increased bacteria in the gut due to increased undigested lactose leads to increased release of hydrogen by bacteria). Acidic stool may also be an indication
In a newborn, at what percentage of conjugated bilirubin of the total bilirubin should you be concerned for obstructive jaundice?
≥20% of the total
How can swallowed maternal blood (from delivery or from cracked nipples) be differentiated from an infant’s in an infant with bloody stool?
With an Apt (or Apt-Downey) test - distinguishes fetal hemoglobin from adult hemoglobin based on the specimen’s reaction to alkali (fetal hemoglobin is unchanged, whereas adult hemoglobin changes to hematin
What is the initial diagnostic test of choice for necrotizing enterocolitis?
Plain film radiographs - will see pneumatosis intestinalis
What is the treatment for necrotizing enterocolitis?
Antibiotics unless there is perforation (surgical emergency)
