Disseminated Intravascular Coagulation (DIC): This condition is characterized by both thrombotic and hemorrhagic complications due to the consumption of platelets and clotting factors. The presence of fever, thrombocytopenia, and anemia, especially with a normal bone marrow biopsy, could suggest a consumptive process like DIC.

Severe Infection or Sepsis: Infections can cause fever, thrombocytopenia (due to consumption or bone marrow suppression), and anemia (due to chronic disease or hemolysis). A normal bone marrow biopsy might be seen if the infection is not directly involving the marrow.
Immune Thrombocytopenic Purpura (ITP): Although ITP primarily presents with thrombocytopenia, it can be associated with anemia if there is significant bleeding. Fever might not be a primary symptom but could be present if there's an underlying infection.
Hemophagocytic Lymphohistiocytosis (HLH): This is a condition of pathologic immune activation characterized by fever, cytopenias (including anemia and thrombocytopenia), and hemophagocytosis, which might not always be evident on a bone marrow biopsy.

Thrombotic Thrombocytopenic Purpura (TTP): A rare disorder characterized by thrombocytopenia, microangiopathic hemolytic anemia, renal failure, neurological symptoms, and fever. It's crucial to diagnose TTP early due to its high mortality rate if left untreated.
Hantavirus Syndrome: Certain hantaviruses can cause a syndrome that includes fever, thrombocytopenia, and anemia, among other symptoms. It's essential to consider this diagnosis, especially in patients with a relevant travel or exposure history.
Malaria: In areas where malaria is endemic, it should be considered in patients with fever, anemia, and thrombocytopenia. Malaria can cause these symptoms due to the destruction of red blood cells and the consumption of platelets.

Paroxysmal Nocturnal Hemoglobinuria (PNH): A rare, acquired, life-threatening disease of the blood characterized by the destruction of red blood cells (hemolysis), bone marrow failure, and the potential for blood clot formation (thrombosis). Fever and thrombocytopenia can be part of the presentation.
Atypical Hemolytic Uremic Syndrome (aHUS): A rare disease that primarily affects kidney function and can cause anemia, thrombocytopenia, and fever among its symptoms. It's essential to consider aHUS in the differential diagnosis due to its severity and the need for specific treatment.