ABEM Toxicology, Environmental & Infectious Diseases 5

Question 1

A patient on warfarin presents with an INR of 9.8 and active intracranial hemorrhage. Which is the FASTEST and most appropriate reversal strategy?

Accepted Answer

4-factor prothrombin complex concentrate (4F-PCC)

Answer

4-factor PCC reverses warfarin-related INR within minutes, contains all vitamin K-dependent factors, requires small volume, and is superior to FFP for emergent reversal.

Question 2

A patient presents with fever, hepatosplenomegaly, and pancytopenia after returning from a tropical trip; a bone marrow biopsy shows macrophages engulfing red blood cells and platelets. What is the diagnosis?

Accepted Answer

Visceral leishmaniasis (kala-azar)

Answer

Visceral leishmaniasis (kala-azar) causes macrophage invasion of the reticuloendothelial system, presenting with fever, massive splenomegaly, and pancytopenia in a returning traveler.

Question 3

Which ECG finding in a patient with digoxin toxicity is MOST specific for toxicity rather than therapeutic effect?

Accepted Answer

Bidirectional ventricular tachycardia

Answer

Bidirectional ventricular tachycardia is highly specific for digoxin (and aconitine) toxicity and is not a therapeutic ECG change.

Question 4

A patient presents with fever, cough, and bilateral hilar lymphadenopathy after disturbing bat guano in an Ohio cave. Bronchoalveolar lavage reveals intracellular yeast within macrophages. What is the treatment for severe pulmonary disease?

Accepted Answer

Amphotericin B lipid complex

Answer

Severe or disseminated histoplasmosis requires amphotericin B lipid formulation as initial therapy, followed by step-down to itraconazole after clinical improvement.

Question 5

A construction worker collapses on a hot summer day with core temperature of 41.5°C, anhidrosis, and delirium. What is the MOST effective cooling method to reduce core temperature rapidly?

Accepted Answer

Ice water immersion

Answer

Ice water immersion provides the fastest rate of core cooling (0.2°C/min) for exertional heat stroke and is the gold standard cooling method.

(ABEM) American Board of Emergency Medicine Practice Test

(ABEM) American Board of Emergency Medicine Practice Test

ABEM Toxicology, Environmental & Infectious Diseases 5