Emergency Medicine is fantastic--I am posting here today because scheduling allowed me a three and a half day weekend this block! Much better than my colleagues in Medicine, Surgery, or OB-GYN--it would never happen on those rotations.
Let's do a case. A 42-day old infant girl presents at 8pm, upgraded from the pediatric urgent care center located at your ER (don't you wish you had one!), with bleeding from the rectum. The parents were concerned because of a 5 day history of worsening blood mixed with mucous (currant jelly) and a normal appearing green stool. Stooling frequency unchanged--4-5x per day. No apparent pain with passing stool or abdominal pain, no vomiting, no fever. Weight gain was appropiate, and baby did not seem overly fatigued, although mother thought she was a little pale. No recent antibiotic use or NSAID use reported for baby or mother. They had come to the our ER after it started and baby was started on a soy based formula and sent home. 1 day previously, baby was started on Neutramigen (last resort before hyperalimentation), but the bleeding had worsened--more obvious blood in the stools for the last day. Prior to starting the soy based formula, baby had been breast feeding. Mother had had cracked nipple previously about two weeks ago with a little bleeding, but it had resolved after 2 days. Baby had been born 2 days post dates by C-section for failure to progress. Normal primigravida prenatal course, no NICU time, no peri-natal infections reported. Parents report an iguana and two dogs in the house, are non-smokers, have no medical problems, and the baby has no siblings.
On exam, baby was well appearing, in no distress, and appeared well hydrated, with no pallor or jaundice. Mild baby acne over L lateral face and forehead seen. VSS, afeb. No bruises noted on skin. Oro-nasopharyngeal exam revealed pink mucosa without bleeding, hyperemia, or thrush. Normal cardiovascular and lung exam. Normal bowel sounds. No tenderness, distension, or masses on abdominal exam, no organomegaly. No caput medusa. No cracks, fissures, or hemmorhoids appreciated. During the (normal) digital rectal exam,I got an episode of forceful pooping for my trouble, getting baby shit on my pants, eliciting knowing smiles from the parents, and endearing me to them forever. Strongly guiac positive semisolid green stool mixed with red mucous.
CBC revealed a HB/Hct of 12/36, WBC of 14, plt of 640. Complete metabolic panel within normal limits except for slightly elevated AST/ALT, but normal bilirubin and alkaline phosphatase.
So what's the differential?
--Whenever you see currant jelly stools in a child less than 2, my spastic reflex is "intussusception," which is a good reflex, as this is a dangerous and often-missed diagnosis, it can lead to
"the process progresses to transmural gangrene and perforation of the leading edge of the intussusceptum." . Other features of this diagnosis missing from this picture: altered mental status, intermittent abdominal pain, vomiting, intestinal obstruction, preceeding upper respiratory infection, wrong age--"intussusception occurs in infants aged 5-10 months," and palpable abdominal mass.
--Meckel's diverticulum--which often presents with painless rectal bleeding, and can be a lead point for intussusception. However, in this case: no signs of abdominal pain, the bleeding was relatively mild (Meckel's typically produces profuse rectal bleeding--because of ectopic gastric mucosa ulcerating), wrong time frame (remember 'rule of two's'--2% of population, 2% manifest clinical sx, 2 feet proximal to the terminal ileus, and 45% of symptomatic patients are less than two years old) and again, no sign of obstruction, and the patient did not appear acutely ill (which would prompt perhaps a search for a meckel's--typically via Meckel's scan, a nuclear test.).
--Necrotizing enterocolitis: Less common in normal birth weight babies, no peritoneal signs, and simply not ill.
-- swallowed maternal blood--excluded by history in this case--cracked nipple most common--not an issue here.
--Anal fissures, cracks, and fistulas--rectal exam is mandatory in case of rectal bleeding, fortunately negative in this case.
--Milk protein allergy--quiet, can last for days after last milk ingestion, can lead to GI bleeding. This ended up being our probable diagnosis.
The patient was discharged after a discussion with the PMD and referral for close GI followup.
*Picture from www.restaurantwidow.com