Recrudescence of Plasmodium falciparum Malaria in a Patient With Progressive Sarcoidosis Joseph Allencherril, MD,* Allexa Hammond, MD,† Gilad Birnbaum, MD,* Benjamin Gold, MD,* Ronan Allencherril, BA,‡ Katherine Salciccioli, MD,* and Hana El Sahly, MD§ Abstract: Although endemic malaria has largely been eradicated in the United States, cases still occur, often as a result of travel-related exposure. Although nearly all cases of Plasmodium falciparum malaria occur within 3 months of exposure, in rare instances, symptoms manifest years after the sentinel infection because of compromise of immunity and parasite recrudes- cence. We describe a case of a 49-year-old woman with a history of child- hood malaria and no recent travel history who presented with P. falciparum malaria in the setting of progressing pulmonary sarcoidosis. This case report highlights the role of advancing immune compromise status in malarial re- crudescence. We also consider other potential avenues to explain how a pa- tient might develop P. falciparum malaria in a nonendemic region in the absence of recent travel. Key Words: malaria, immunoregulation, plasmodium, travel medicine (Infect Dis Clin Pract 2019;27: 102–104) T he worldwide burden of malaria is significant, with 214 million cases of symptomatic malaria estimated in 2015. 1 In developed countries such as the United States, where endemic malaria elim- ination efforts have been successful, reported malaria cases are largely travel related. The Centers for Disease Control and Pre- vention (CDC) estimate that roughly 1700 cases of malaria are diagnosed in the United States each year, most of which occur in returning travelers. 2 CASE REPORT A 49-year-old Nigerian woman with pulmonary sarcoidosis presented to the emergency department with 1 week of nocturnal fevers and right upper quadrant pain. The maximum measured temperature at home was 102°F. The patient described the abdom- inal pain as achy without associated aggravating or relieving fac- tors, nausea, vomiting, or diarrhea. She also reported fatigue with intermittent headaches but denied neck stiffness, photophobia, dys- uria, chest pain, cough, worsening dyspnea, arthralgias, skin rashes, or changes in weight. Medical history was notable for multiple treated episodes of malaria as a child, with her last bout of malaria at the age of 12 years. She was not on immunosuppressive therapy for pulmonary sarcoid- osis given stable symptoms over the past several years. She was tak- ing no medications or supplements and denied recent sick contacts. The patient was unemployed and had lived in Houston for 12 years since emigrating from Nigeria. She last traveled to Nigeria 4 years before her presentation and regularly came into contact with recent Nigerian immigrants at social functions in the United States, such as church gatherings. However, there was no household con- tact with returning travelers. She denied recent sexual activity, al- cohol, tobacco, and intravenous drug use, and history of blood transfusions. The patient had no history of surgeries or recent hos- pitalization. She had no known allergies. On admission, the patient appeared tired. She was afebrile with a heart rate 112 beats/min, blood pressure of 98/54 mm Hg, respiratory rate of 18 breaths/min, and oxygen saturation of 99% on room air. Physical examination was notable for conjunc- tival pallor, a low-pitched II/VI systolic murmur at the right upper sternal border, and mild right upper quadrant abdominal tender- ness with negative Murphy sign. No hepatosplenomegaly was noted, and there were no meningeal signs or nuchal rigidity. Initial laboratory assays showed a white blood cell count of 11,000/μL with atypical lymphocytes and a normal differential, hemoglobin level of 9.0 mg/dL with mean corpuscular volume of 83 fL, and platelet count of 54,000/μL. Creatinine was 1.4 mg/dL (elevated from a baseline of 0.8 mg/dL), and total bilirubin was 1.0 mg/dL with an otherwise normal electrolytes and liver enzymes panel. HIV antibody screening was negative. Although there was initially no clinical suspicion of malaria given the remote travel history to Nigeria, the automated hematol- ogy reading revealed “atypical lymphocytes” in the blood, which were confirmed by a laboratory technician to be intracellular tro- phozoites in red blood cells on a peripheral blood smear (Fig. 1). The level of parasitemia was estimated to be 3%. A rapid diagnostic test for Plasmodium falciparum antigen showed a positive result, and the result of subsequent confirmatory polymerase chain reac- tion for P. falciparum was positive. The patient was diagnosed as having severe malaria recru- descence, given her acute kidney injury. Accordingly, a regimen of quinidine and doxycycline was started with prompt resolution of parasitemia and marked clinical improvement. Repeat periph- eral blood smear at 24 hours showed reduction of parasitemia to less than 0.3%. The patient's fevers and abdominal pain rapidly abated with treatment. Computed tomography of the chest (Fig. 2) obtained during this admission demonstrated innumerable pulmo- nary nodules in a perilymphatic distribution throughout the lungs, increased from a year prior, consistent with marked progression of pulmonary sarcoidosis. Eighteen months later, the patient was do- ing clinically well with normal clinical and laboratory parameters. We postulate that sarcoidosis progression was the immune- altering trigger that resulted in P. falciparum malaria recrudes- cence from an infection that occurred at least 4 years ago. DISCUSSION Despite the official declaration of malaria eradication in the United States by the CDC in 1950, domestic cases are still observed annually, especially in patients with a history of recent travel to endemic areas. 1 From the *Department of Medicine, Baylor College of Medicine, Houston; †De- partment of Medicine, University of Texas Southwestern Medical Center, Dallas; ‡University of Texas Medical Branch, Galveston; and §Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX. Correspondence to: Joseph Allencherril, MD, Department of Medicine, Baylor College of Medicine, Houston, One Baylor Plaza, Houston, TX 77030. E‐mail: allenche@bcm.edu. The authors have no funding or conflicts of interest to disclose. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved. ISSN: 1056-9103 CASE REPORT 102 www.infectdis.com Infectious Diseases in Clinical Practice • Volume 27, Number 2, March 2019 Copyright © 2019 Wolters Kluwer Health, Inc. 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