Name 6 causes of GI bleeding in neonates (< 1 month)? What is your clinical approach to diagnosis?

1. anorectal fissures (most common cause of rectal bleeding in patients less than 1 year)
2. swallowed maternal blood (examine mother's nipples)
3. coagulopathy
4. necrotizing enterocolitis 
5. malrotation with midgut volvulus 
6. Hirschsprung disease 

If patient appears well and there is an obvious cause of bleeding such as a fissure or swallowed maternal blood, a minimalist workup can probably be pursued with close outpatient followup.  However, if the patient is ill and/or there is no obvious cause of bleeding consider checking labs and an abdominal x-ray to start.  


Source

Ramsook, C. and Endom, E.  "Diagnostic approach to lower gastrointestinal bleeding in children"  Up to Date. May 2011.