32 yo M no sig PMH presents to ED with low grade, fevers, cough, SOB, and bodyaches for 4-5 days, symptoms are getting progressively worse. Pt had abdominal cramping, nausea, and diarrhea that preceded respiratory symptoms and began 1-2 weeks ago. He recently came back 2 days ago from Patagonia, Chile where he was camping for 6 weeks. No headache, neck pain, chest pain, abd pain, vomiting, dysuria, rash, or edema. VS: T 38, HR 120, BP 120/70, RR 40, O2 sat 88% RA. Labs significant for atypical lymphocytes with bandemia, hemoconcentration, renal failure and thrombocytopenia. Chest XR shows bilateral peripheral interstitial opacities, consistent with pulmonary edema. Pt quickly decompensates in the ED and becomes hypoxic and hypotensive. He fails trial of BiPAP, requires intubation and pressors. What could this patient have and what treatment should you consider?
- Hantavirus General Information
- Organism: Bunyaviridae virus
- Vector: deer mice
- Transmission: inhalation of aerosols containing rodent urine or feces.
- Seen in the southwestern United States, South and Central America
- Shock is partly cardiogenic and partly disseminated circulatory shock.
- Clinical Presentation
- Initial symptoms are nonspecific and occur 1-5 weeks after exposure: fever, malaise, myalgia, nausea, vomiting and diarrhea
- Can quickly progress to fulminant ARDS-like picture
- NOTE: signs that DO NOT occur with Hantavirus Pulmonary Syndrome are rash, hemorrhage, petechiae, peripheral or periorbital edema.
- Initial symptoms are nonspecific and occur 1-5 weeks after exposure: fever, malaise, myalgia, nausea, vomiting and diarrhea
- Diagnosis
- Mainly a clinical diagnosis
- Labs may show thrombocytopenia, atypical lympthocytes with bandemia or blasts, hemoconcentration, and renal failure.
- Chest XR may show bilateral perihilar or interstitial infiltrates consistent with pulmonary edema
- Serology (ELISA) available through the CDC.
- Treatment
- There is no specific therapy for hantavirus infection; Treatment is primarily supportive, ABCs.
- If ARDS picture predominates intubate with ARDS settings: low TV (4-6cc/kg ideal body weight), higher PEEP (start at 5). If shunt is present, increase PEEP. Remember if shunt is present you must increasing PEEP since shunt is unresponsive to oxygen. Keep plateau pressures below 30.
- Aggressive fluid hydration and steroids may be given if adrenal shock occurs
- In a young person with reversible cardiopulmonary shock extracorporal membrane oxygen (ECMO) should be considered.
Thank you Dr Teran for this case.
References:
University of Maryland Emergency Medicine, Hantavirus, available at https://umem.org/educational_pearls/1896/
Center for Disease Control. (2012). Hantavirus. Retrieved September 3, 2012, from http://www.cdc.gov/hantavirus/index.html
Berger, S. A., Calisher, C. H., and Keystone, J. H., (2003). Exotic Viral Disease: A Global Guide. Hamilton, Ontario: BC Decker.