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INTRODUCTION: Babesiosis, or Babesia microti in the blood, is a rare tickborne parasitic illness. It is endemic to the Northeast and upper Midwest regions of the United States, in warmer summer months, and is a reportable disease. Babesia is transmitted by the bite of an infected Ixodes scapularis nymph tick (black-legged or deer tick). Many people remain asymptomatic, while others experience life-threatening illness. even with low parasite index, such as the case described. Cases are rising in Pennsylvania overall since 2010, but since the start of COVID-19 pandemic, our small community hospital in rural Northeastern Pennsylvania (NEPA) has seen 12 cases. DESCRIPTION: A 63-year-old male presented with severe illness due to persistent Babesiosis parasitemia in a NEPA community hospital, with history of recent COVID-19 infection. He presented with fever, rigors, myalgias, diarrhea, and weakness. He reported history of tick bite two weeks prior to presentation. Initial exam was unremarkable. He was admitted to the hospital with hyponatremia, acute liver and kidney injury, anemia, thrombocytopenia, and elevated bilirubin. Babesia microti red blood cell (RBC) parasite index initially was 2%. He then became lethargic and hypotensive and parasite index escalated to 5% with worsening febrile illness, confusion, rapid atrial fibrillation, worsening acute kidney injury, and evidence of hemolysis and consumptive coagulopathy, despite standard-of-care antimicrobial regimen. He was fluid resuscitated and transferred to a higher level of care for urgent RBC exchange, which he obtained, and recovered after prolonged intensive care unit stay. DISCUSSION: Babesiosis can present indolently or acutely with flu-like and hemolytic illness. Those at higher risk of illness are elderly, and those with asplenia, baseline liver or kidney dysfunction, or immunocompromised status. Babesia cases are rising all over the country. Our single small hospital has seen 12 cases in the past 3 years. It is a possibility that the recent COVID-19 infection created a relative immunocompromised and pro-inflammatory state leading to susceptibility to the parasite. Illness can be life-threatening. Even with low parasitemia index, early RBC exchange should be considered if end organ dysfunction is present and clinical course is not improving.
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SESSION TITLE: Unusual Critical Care SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/18/2022 10:15 am - 11:10 am INTRODUCTION: Babesiosis can have a clinical spectrum ranging from mild illness in most cases to more severe manifestations in immunosuppressed individuals or in those with high-grade parasitemia. This patient had severe babesiosis resulting in ARDS and shock in spite of being immunocompetent and having low-grade parasitemia, making it a rare presentation. CASE PRESENTATION: A 49-year-old, previously healthy woman, was admitted with high-grade fevers. Physical exam findings were normal, except for fever (103 F). Initial lab results were significant for hemolytic anemia and thrombocytopenia. Chest radiography was normal. Other microbiology studies, including COVID-19, were negative. Empiric antibiotic therapy with piperacillin-tazobactam and doxycycline was started. Peripheral smear identified rare, minute intracellular ring forms, suspicious for babesia. IV azithromycin and oral atovaquone were started. PCR was done to confirm the diagnosis and Babesia microti DNA was detected. As peripheral smear showed parasitemia of only 1% (percentage of red blood cells infected), exchange transfusion was not considered as a treatment option. Two days after admission, worsening hemodynamic and respiratory status was noted with increasing oxygen requirements. CT chest now revealed diffuse interstitial infiltrates. ARDS ensued and the patient was intubated and started on mechanical ventilation with vasopressor support. Immunodeficiency workup was normal. In view of clinical deterioration, the antimicrobials were switched from atovaquone and azithromycin to IV clindamycin and quinidine for 14 days. After a protracted ICU stay, the patient showed gradual clinical improvement, parasitemia resolved, and she was eventually discharged to a rehabilitation facility. DISCUSSION: Babesiosis is a tick-borne infectious disease endemic to the North-East and Midwest United States. Majority of the infections are self-limited. However, in immunocompromised individuals and in those with high-grade parasitemia (>10%), it manifests as a severe illness with ARDS, severe hemolysis, or shock. Diagnosis is made by identifying parasites on thin peripheral blood smears with Giemsa/Wright stains. PCR can be used for species identification and for confirming the diagnosis in cases with low-grade parasitemia (<4%). IV azithromycin plus oral atovaquone is the preferred initial regimen and IV clindamycin plus quinidine is an alternative combination that can be used in severe infection. Red blood cell exchange transfusion can be considered in patients with high-grade parasitemia or organ failure. CONCLUSIONS: Babesiosis can very rarely cause ARDS and shock in immunocompetent patients with low-grade parasitemia. Prompt diagnosis and escalation of antimicrobial regimens to clindamycin and quinidine in such cases can lead to improved clinical outcomes. Exchange transfusion can serve as a treatment option in patients with high-grade parasitemia. Reference #1: Ord RL, Lobo CA. Human babesiosis: Pathogens, prevalence, diagnosis, and treatment. Current clinical microbiology reports. 2015 Dec;2(4):173-81. Reference #2: Ripoll JG, Rizvi MS, King RL, Daniels CE. Severe Babesia microti infection presenting as multiorgan failure in an immunocompetent host. Case Reports. 2018 May 30;2018:bcr-2018. Reference #3: Sanchez E, Vannier E, Wormser GP, Hu LT. Diagnosis, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis, and babesiosis: a review. Jama. 2016 Apr 26;315(16):1767-77. DISCLOSURES: No relevant relationships by Shankar Chhetri No relevant relationships by Vasudev Malik Daliparty No relevant relationships by Preethi Dendi No relevant relationships by samer talib
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Diagnosing and treating many infectious diseases depends on correctly identifying the causative pathogen. Characterization of pathogen-specific nucleic acid sequences by PCR is the most sensitive and specific method available for this purpose, although it is restricted to laboratories that have the necessary infrastructure and finance. Microscopy, rapid immunochromatographic tests for antigens, and immunoassays for detecting pathogen-specific antibodies are alternative and useful diagnostic methods with different advantages and disadvantages. Detection of ribosomal RNA molecules in the cytoplasm of bacterial and protozoan pathogens by fluorescence in-situ hybridization (FISH) using sequence-specific fluorescently labelled DNA probes, is cheaper than PCR and requires minimal equipment and infrastructure. A LED light source attached to most laboratory light microscopes can be used in place of a fluorescence microscope with a UV lamp for FISH. A FISH test hybridization can be completed in 30 min at 37 °C and the whole test in less than two hours. FISH tests can therefore be rapidly performed in both well-equipped and poorly-resourced laboratories. Highly sensitive and specific FISH tests for identifying many bacterial and protozoan pathogens that cause disease in humans, livestock and pets are reviewed, with particular reference to parasites causing malaria and babesiosis, and mycobacteria responsible for tuberculosis.