Diarrhea

Definition

• • Acute diarrhea consists of abrupt onset of increased frequency and/or fluidity of BM.

    • Inf. agents, toxins, and drugs are the major cause of acute diarrhea.

    • In hospitalized patients, pseudomembranous colitis, ABx or drug associated diarrhea, and fecal impaction should be considered.

  • Chronic diarrhea consists of passage of loose stools with or without increased stool frequency for more than 4 weeks.

Diagnosis

• • Most acute infectious diarrheal illnesses last <24 hours and could be viral etiology; therefore, stool studies are unnecessary in short lived episodes without fever, dehydration, or presence of blood or pus in the stool.

  • Stool cultures, C. diff toxin assay, ova and parasite examinations, and flex sig may be needed in pt w/ severe, prolonged, or atypical sx.

  • Fecal osmotic gap can be calc in pt w/ ch diarrhea and voluminous watery stools as follows: 290 - 2(stool Na + stool K)

    • Secretory diarrhea: stool osmotic gap is <50 mOsm/kg

    • Osmotic diarrhea: stool osmotic gap is >125 mOsm/kg.