Case Presentation: A 73-year-old male with a history of heart failure with preserved ejection fraction presented with one month of dizziness, weakness, dyspnea on exertion, and a 25-pound weight loss due to loss of appetite. On the day of admission, he had three brief episodes of syncope upon standing. His initial blood pressure was 64mmHg/40mmHg, which improved to 93mmHg/47mmHg after two liters of intravenous fluids. On exam he appeared fatigued with conjunctival pallor. His initial labs showed pancytopenia with a hemoglobin of 9.7 g/dL, platelet count of 122 × 10^9/L, and white blood cell count of 2.7 x 10^9/L. There was evidence of hemolysis with elevated total bilirubin and LDH, and a low haptoglobin. He was not vaccinated against COVID-19, and his COVID-19 test was positive. No insect bites were reported, however upon admission to the hospital, the patient was empirically treated with azithromycin, atovaquone, and doxycycline due to local concern for tick-borne illnesses. His peripheral smear subsequently showed intra-erythrocytic parasites consistent with babesiosis (see Figure 1). Doxycycline was stopped once his tick panel was positive only for Babesia. He never required oxygen therapy or other treatment for his COVID-19 infection. The patient improved rapidly, supporting his medical readiness for discharge, with resolution of pancytopenia and hemolysis in the outpatient setting.
Discussion: Rates of hospitalization for COVID-19 are high across the country. Patients often have co-existing medical conditions that can complicate the clinical presentation. As seen in this case, babesiosis and COVID-19 share many common symptoms such as fevers, chills, arthralgias, and weakness (CDC, 2019). Severe babesiosis often presents with hemolytic anemia and its sequelae, which can lead to a need for hospitalization. Some of these complications include disseminated intravascular coagulation, hemodynamic instability, and respiratory failure, all of which have also been seen in COVID-19 infections (CDC, 2019). Recently, COVID-19 has also been found to be associated with cases of hemolytic anemia, similarly to babesiosis (Lazarian, et al. 2020). Additionally, babesiosis and COVID-19 have common risk factors for severe disease, such as immunocompromised states and advanced age (Krause, et al. 2020). Interestingly, atovaquone and azithromycin, which are used to treat babesiosis, are being studied for use together in treatment of COVID-19, and atovaquone may provide benefit on its own due to its ability to inhibit viral replication (Farag, et al. 2020). Our patient improved as expected with appropriate treatment for babesiosis. It is possible that this treatment may also have limited the severity of his COVID-19 infection, despite risk factors for severe disease, though no definitive conclusions can be drawn without additional research in this area.
Conclusions: Given the high prevalence of babesiosis in endemic areas, co-infection is a possibility with many other illnesses. Tick-borne infections often present with non-specific symptoms that resemble the initial symptoms of COVID-19. During the pandemic, COVID-19 has been presumed to be the primary cause of many varied presentations of illness. However, clinicians need to maintain a high level of suspicion for concurrent tick-borne illnesses in areas where such illnesses are endemic.
