Severe Anaplasmosis With Multiorgan Involvement in a Rheumatoid Arthritis Patient

Anaplasmosis, caused by the tick-borne bacterium Anaplasma phagocytophilum, is an emerging infectious disease with a broad spectrum of clinical manifestations. Here, we present case report 66-year-old Caucasian woman residing in Connecticut who exhibited severe anaplasmosis multi-organ involvement. The patient, medical history rheumatoid arthritis and hypothyroidism, presented confusion, lethargy, fever, myalgia, generalized weakness, poor appetite May 2023. Laboratory investigations revealed pancytopenia, hyponatremia, elevated liver enzymes mild hyperbilirubinemia, lactic acidosis. A buffy coat smear analysis demonstrated basophilic intracytoplasmic inclusion bodies neutrophils, supporting diagnosis anaplasmosis. Prompt administration doxycycline, recommended treatment for anaplasmosis, was initiated. However, patient subsequently developed acute respiratory distress syndrome (ARDS) necessitating heated humidified high-flow nasal cannula (HFNC) therapy. polymerase chain reaction (PCR) confirmed presence patient's blood. Following doxycycline treatment, improvement peripheral blood findings, resolution ARDS, complete neurologic recovery. This underscores potential severity diverse manifestations highlighting importance early recognition, prompt diagnosis, timely initiation appropriate to prevent complications improve outcomes.