A Synopsis of AFP's "Gastroenteritis in Children: Part I. Diagnosis"

Gastroenteritis in Children: Part I. Diagnosis
CATHERINE A. CHURGAY, MD, Hope Medical Clinic, Ypsilanti, Michigan
ZAHRA AFTAB, MD, St. Luke’s Hospital/University of Toledo, Maumee, Ohio

Am Fam Physician. 2012 Jun 1;85(11):1059-1062.
http://www.aafp.org/afp/2012/0601/p1059.pdf

     Acute gastroenteritis in children is most commonly due to infection. Diarrhea (3 or more loose or watery stools in 24 hours) is often seen with gastroenteritis. It is due to virus (rotavirus) 85% of the time, bacteria (Campylobacter, Shigella, Salmonella) 15% of the time,  travelers diarrhea (E. coli enterotoxin) 10% of the time, and parasites (Giardia, Cryptosporidium) less than 5% of the time. The differential diagnosis includes IBD, intussusception, membranous colitis, food allergy, sepsis, pneumonia, meningitis, UTI and others.
     Noninflammatory diarrhea is watery without blood, mucus or fever. It commonly involves the small intestine and does not destroy the lining. Inflammatory diarrhea will have blood and leukocytes in the stool. It commonly involves the large intestine and may be associated with pain, tenderness, fever or vomiting.
     Diarrhea lasting more than 14 days may be due to a parasite. Diarrhea with neurological changes may be to toxins. Bacterial and viral bacterial may have systemic symptoms such as weakness, arthritis, fever, or jaundice.
     The history and exam should focus on the patient's hydration status. Clinicians should ask about urination quality and quantity, bowel moments, vomiting, oral intake, stool quality, presence of fever, mental status, and history of other illnesses. Weighting the child can help assess the volume status of the patient. The degree of dehydration can be classified into none (less than 5%) , mild/moderate (5-10%), and severe (10% or more).  Factors that may signal dehydration may be overall appearance, capillary refill time greater than two seconds, absence of tears, and dry mucus membranes.  Two of these factors would be present in a patient with at least 5% dehydration. Presence of three of these features would be seen in a patient with 5-10% dehydration. A patient with more than 10% dehydration would have four of these factors. Dehydrated patients may have hypercapnia and acidosis. Urine specific gravity, serum electrolytes. and BUN are not very helpful. A bicarbonate level can give certain clues as to if the patient will need to be admitted  (a bicarb less than 13). Stool for ova and parasite need only be ordered in cases of persistent diarrhea (greater than 2 weeks) or if there is evidence of an outbreak.