Patient is a 62 year old male with a past medical history of hypertension presented to the emergency department (ED) with 4 days of watery, non-bloody diarrhea occurring throughout the day with concurrent diaphoresis, chills, and high fever ranging from 102 to 105 F with minimal improvement on acetaminophen. He reported a significant decrease in appetite and oral intake. He had a recent trip to upstate New York and returned about 2 weeks ago. During this trip, he noticed numerous mosquito bites, but denied having any rashes, tick bites, sick contacts or any travel abroad. On exam, he was found to be diaphoretic, tachycardic and febrile with a temperature of 102.9F. The abdominal exam revealed normal bowel sounds in all four abdominal quadrants, was nondistended, soft and nontender to palpation. No hepatosplenomegaly was present. On admission the labs were notable for white blood cell count 3.08 × 103/mcL (normal: 4.8–10.80 × 103/mcL), which reduced to 0.93 × 103/mcL during the hospitalization day 2, hemoglobin 15.5 g/dL (normal: 14.0–18.0 g/dL) initially but 11.1 g/dL on hospitalization day 2, platelet count 27,000/mcL (normal: 150-450 × 103/mcL), fibrinogen 410 mg/dL (normal: 200–393 mg/dL), lactate dehydrogenase (LDH) 511 U/L (normal: 135–225 U/L), and D-Dimer: 6,172 ng/mL DDU (normal: 0–243 ng/mL DDU), aspartate aminotransferase 76 U/L (normal: 5–40 U/L) and rest of the lab including haptoglobin, human immunodeficiency virus (HIV), hepatitis panel and electrolytes were within normal range. Hematology was also consulted for pancytopenia and direct antiglobulin tests IgG level and C3 level were negative, flow cytometry studies were unremarkable, and no schistocytes seen on peripheral smear. The common causes of secondary immune thrombocytopenic purpura (ITP) were ruled out using the lab results. The patient was negative for HIV and HEP C, which are the two predominant viral causes of secondary ITP. The fibrinogen levels were normal and peripheral smear did not show microangiopathic pathology which outlawed the possibility of disseminated intravascular coagulation (DIC). Chest radiography was negative for consolidation, or infiltrates and the computed tomography (CT) Pulmonary angiography was negative for pulmonary embolism. The CT abdomen & pelvis with contrast showed an incidental 11mm cystic lesion adjacent to the pancreatic body and primarily emphasized findings suggesting viral enterocolitis (, ). The patient received multiple units of platelet transfusion in the setting of febrile thrombocytopenia less than 20,000/mcL. The patient was treated with empiric antibiotics given the concern for infection with vancomycin 1000mg daily, cefepime 1g every 12 hours and metronidazole 500mg every 8 hours to cover anaerobes given CT findings. Full infectious workup including blood cultures, stool culture, clostridium difficile antigen, ova and parasite tests were all negative. Tick borne infectious disease serologies were unremarkable for babesia, rocky mountain spotted fever, ehrlichia or lyme antibodies. Ultimately, the patient was found to have anaplasma phagocytophilum antibodies positive and a diagnosis of HGA was made. The antibiotics were stopped and were switched to doxycycline 100mg every 12 hours with planned for ten days. The patient had a rapid clinical improvement and the pancytopenia improved. The patient was discharged home to complete the ten day course of doxycycline and was followed up in the outpatient clinic. At the outpatient clinic, the patient continued to show improvement of his symptoms and labs showed resolution of pancytopenia. The predominant challenge in this case was figuring out the cause of the pancytopenia in this patient. It was crucial for the clinician to dig deep and have a detailed history by covering salient points, giving the treating clinician a more holistic picture in order to ascertain the cause of pancytopenia. Furthermore, the investigative workup was initially significant only for thrombocytopenia, lending to the possibility of conversion to pancytopenia after one week.