A 9-year-old castrated male mixed breed dog was presented to Cornell’s Emergency Service on referral for further evaluation of less than a week’s history of lethargy, melena, and hematochezia. The patient had visited his primary care veterinarian for these clinical signs two days before presentation to Cornell and been diagnosed with severe thrombocytopenia and mild regenerative anemia on a complete blood count. At this time he also tested weakly positive for antibodies to Anaplasma on a 4Dx test. The referring veterinarian prescribed oral prednisolone, doxycycline, and famotidine but the patient failed to improve after two days, prompting referral. On presentation, the patient was quiet, alert, and responsive. The only physical exam abnormalities were pale pink mucous membranes, gingival petechiae, ecchymoses on his ventral abdomen, and black tarry stool on the thermometer probe. Quick assessment tests revealed a moderate anemia and severe hypoproteinemia. Coagulation testing revealed no abnormalities. A complete blood count submitted at this time revealed a platelet count of 11 thou/uL. Thoracic radiographs and abdominal ultrasound were unremarkable. Main differentials at this time included immune-mediated thrombocytopenia or rickettsial infection. The following day, the patient was transferred to Cornell’s Internal Medicine Service. The patient had become hypovolemic and more severely anemic overnight, so a packed red blood cell transfusion and fluid bolus were initiated. Vincristine treatment was initiated as a rescue drug for his thrombocytopenia. After a repeat CBC revealed a non-regenerative anemia and multiple dysplastic lineages, a bone marrow aspirate was performed to investigate whether his disease process affected blood cell precursors. Intravenous immunoglobulin therapy was also initiated after the aspirate. The patient’s platelets returned to normal levels and he was discharged. Multiple re-checks confirm that the patient has maintained adequate platelet and RBC levels and remains clinically well.