A 47-year-old guy with a fever and weariness visits the emergency room. His antiretrovirals have not been taken consistently, and he has a history of HIV. Blood pressure is 110/70 mm Hg, his temperature is 38.3 C (100.9 F), his pulse is 104/min, and his respirations are 20/min. Hepatosplenomegaly and a number of erythematous papules are prominent physical examination findings. Pancytopenia is evident through laboratory tests. Testing for histoplasma antigen is successful. For the treatment of disseminated histoplasmosis, amphotericin B is administered intravenously. The patient experiences palpitations and weakness a day later. Frequent premature ventricular beats are seen on an ECG. If these new signs and symptoms are caused by drug toxicity, they are most likely related to which of the following?

Question

Quizplus · Accepted Answer

Eductional Objective: Amphotericin B's nephrotoxicity, which results from both a decline in glomerular filtration rate and immediate toxic effects on the tubular epithelium, is the most serious side effect. Anemia (reduced erythropoietin production) and altered electrolytes can result from nephrotoxicity. The distal tubule's increased membrane permeability results in an increase in the prevalence of hypokalemia and (less frequently) hypomagnesemia. Arrhythmias and paralysis can also result from hypokalemia. T wave flattening, ST-segment depression, strong U waves, and early atrial and ventricular contractions are all ECG symptoms of hypokalemia. Ventriculoventricular tachycardia or fibrillation can result from severe hypokalemia.

A 47-Year-Old Guy with a Fever and Weariness Visits the Emergency