Case Presentation: A 30 year old female without any past medical history presented to the Emergency Department for 10 days history of persistent fevers. The fever was as high as 104°F and was accompanied by myalgias, headaches, palpitations, and diaphoresis. The remaining review of systems was negative. Aside from fever and tachycardia, a complete physical exam was unremarkable. Lab work showed WBC leukopenia without neutrophil, lymphocyte, or monocyte predominance. A comprehensive metabolic panel was within normal range. Chest x-ray demonstrated clear lungs. Given the suspicion for septicemia due to an unknown pathogen, broad-spectrum antibiotic coverage with Vancomycin and Zosyn was initiated, though she continued to spike fevers. CT scans of the chest, abdomen, and pelvis with intravenous contrast revealed only duodenitis. A comprehensive infectious and rheumatologic work up was negative. Upon further inquiry, the patient’s husband reported that the patient had been consuming Bangladeshi delicacies brought into the United States by family members. Given a concern for food-borne parasites, stool studies were performed, which revealed Giardia lamblia. The patient was switched to intravenous Metronidazole, she defervesced after one dose, and completed a 10-day course of Metronidazole as an outpatient making a full recovery.
Discussion: Giardia is a protozoan parasite capable of causing epidemic or sporadic diarrheal illness. Acute giardiasis typically presents with abdominal complaints, including abdominal pain and diarrhea with or without steatorrhea. Clyne et al., reported a case of fever and urticaria without diarrhea apparently associated with Giardial infection (1). Our patient presented with persistently high fevers without gastrointestinal complaints. The fevers persisted despite broad spectrum antibiotic treatment. She responded to one dose of metronidazole. The mechanism of persistent fever without gastrointestinal symptoms caused by Giardia remains unclear at this time, therefore further investigation is warranted.
Conclusions: Here we report a case of persistently high fevers without gastrointestinal symptoms apparently caused by Giardia infection. Our case suggests that stool studies may be indicated during work up for a fever of unknown origin even in the absence of gastrointestinal symptoms.