Empiric Treatment for Suspected Malaria in the United States: A Case Report

Malaria in the United States is rare and most commonly presents among returning travelers from endemic areas. Diagnosis is classically dependent on a positive blood smear or polymerase chain reaction (PCR) test. The objective of this case report is to highlight a case of suspected malaria in a high-risk individual with negative diagnostic testing where a trial of empiric treatment was initiated based on clinical presentation after a thorough discussion of risks and benefits. However, empiric treatment based on a single case is limiting. We present a case of a 56-year-old man with extensive travel history throughout Asia, who presented after multiple episodes of unprovoked 24-hour fevers over the past seven years. A thorough rheumatologic and infectious inpatient workup was negative and oncology was consulted with low suspicion for malignancy. However, based on clinical presentation and history, malaria remained highly suspected and an empiric trial of anti-malarial treatment was initiated. One year after receiving treatment, the patient has not experienced any further febrile episodes. The efficacy of blood smears and PCR may be influenced by the malarial strain, as some species have low circulating biomass. Therefore, blood smears and PCR testing may not always be diagnostic. Clinical signs supportive of a malarial infection include fever, rigors, chills, hepato/splenomegaly, hyperbilirubinemia, and thrombocytopenia. Malaria is endemic to many regions outside of Africa, including Asia, and should be considered in any returning traveler with recurrent fevers.