EM Quick Hits 63 S-TEC and HUS, IM Epinephrine in OHCA, Dengue, Geriatric Trauma Imaging, TTP

Topics in this EM Quick Hits podcast

Stephen Freedman on pediatric bloody diarrhea, S-TEC and hemolytic uremic syndrome (1:06)

Justin Morgenstern on the evidence for IM epinephrine in out of hospital cardiac arrest (27:04)

Matthew McArther on recognition and ED management of dengue fever (33:56)

Andrew Petrosoniak on imaging decision making in trauma in older patients (47:20)

Brit Long & Michael Gotlieb on recognition and management of TTP (59:10)



Podcast production, editing and sound design by Anton Helman

Podcast content, written summary & blog post by Brandon Ng, edited by Anton Helman, March, 2025

Cite this podcast as: Helman, A. Freedman, S. Morgenstern, J. McArther, M. Petrosoniak, A. Long, B. Gotlieb, M. EM Quick Hits 63 - S-TEC and HUS, IM Epinephrine in OHCA, Dengue, Geriatric Trauma Imaging, TTP. Emergency Medicine Cases. March, 2025. https://emergencymedicinecases.com/em-quick-hits-march-2025/. Accessed September 14, 2025.

Pediatric bloody diarrhea: Shiga Toxin Producing E. Coli (S-TEC) and HUS

Consider obtaining a stool specimen or rectal swab in the ED for PCR testing (not culture) to detect S-TEC, Salmonella, Shigella, and Campylobacter.

Which children with bloody diarrhea require bloodwork? Most children with blood in stool do not require blood work. Indications for bloodwork include:



* Hemodynamic instability

* S-TEC is high on your differential (bloodwork may be useful as baseline)

* Recent travel with bloody diarrhea and fever

* Close contact with S-TEC cases (~10% household transmission rate)



When to suspect S-TEC?



* Severe crampy abdominal pain

* >15-20 small frequent, mucousy, bloody stools per day

* Low grade fever

* Signs of microangiopathy (e.g. petechiae, jaundice)

* Endemic area









Children generally do not require stool O&P for acute diarrhea but should be considered for chronic abdominal pain, chronic diarrhea, or failure to thrive.

When to test for C.difficile? There is a high carriage rate of C. diff (up to ~50% in children under 2 years old). Consider C. diff testing only in children with risk factors such as recent antibiotic use or hospitalization, or as a second line test on follow up if bloody diarrhea persists that is not noted to be from another bacterial etiology.

Why is it important to recognize S-TEC?

A complication of S-TEC infection is Hemolytic Uremic Syndrome (HUS), caused by Shiga toxin accumulation in the kidney which leads to the HUS triad: acute kidney injury, hemolysis, and thrombocytopenia.



* Shiga toxin 2 (STX2) is specifically associated with a 15-20% risk of HUS in children 10 new petechiae appear in a 1 square inch of skin within 1-2 min of cuff deflation)

* Blood work may show leukopenia, thrombocytopenia, and mild liver enzyme elevation

* Confirmatory test for dengue: Viral molecular testing and IgM levels (positive within 4-7 days of infection





* Critical phase (severe cases only): Plasma leakage leading to shock, bleeding, and organ dysfunction



* Treatment: IV fluid resuscitation and supportive care

* Risk factors for developing into severe dengue include extremes of age, immunosuppression, baseline comorbidities, and previous dengue infection





* Recovery phase: Resolution of plasma leakage and hemorrhage. Reabsorption of extravasated fluids



* Some may develop further rashes or severe post-viral fatigue la...