Differential Diagnosis

The patient's laboratory results show a low white blood cell count (WBC) with a left shift, anemia, and thrombocytopenia. Here is a differential diagnosis based on the provided categories:

• Single Most Likely Diagnosis

  • Viral Infection (e.g., Viral Bone Marrow Suppression): The patient's low WBC count, anemia, and thrombocytopenia could be indicative of a viral infection that is suppressing bone marrow function. The low neutrophil percentage and absolute count, along with a high monocyte percentage, support this diagnosis.

• Other Likely Diagnoses

  • Bone Marrow Failure Syndrome (e.g., Aplastic Anemia): The pancytopenia (low WBC, RBC, and platelet counts) could be indicative of a bone marrow failure syndrome. However, the presence of a high monocyte percentage and absolute count makes this diagnosis less likely.
  • Chronic Infection (e.g., Tuberculosis, Endocarditis): Chronic infections can cause pancytopenia and a left shift in the WBC differential count. The high monocyte percentage and absolute count could be indicative of a chronic infection.
  • Hypersplenism: The patient's pancytopenia and splenomegaly (if present) could be indicative of hypersplenism. However, the high monocyte percentage and absolute count are not typical of hypersplenism.

• Do Not Miss Diagnoses

  • Leukemia (e.g., Acute Myeloid Leukemia): Although the patient's WBC count is low, the presence of a left shift and a high monocyte percentage and absolute count could be indicative of leukemia. A bone marrow biopsy would be necessary to confirm this diagnosis.
  • Sepsis: The patient's low WBC count and left shift could be indicative of sepsis. However, the high monocyte percentage and absolute count are not typical of sepsis.
  • Disseminated Intravascular Coagulation (DIC): The patient's pancytopenia and thrombocytopenia could be indicative of DIC. However, the presence of a high monocyte percentage and absolute count is not typical of DIC.

• Rare Diagnoses

  • Myelodysplastic Syndrome (MDS): The patient's pancytopenia and left shift could be indicative of MDS. However, the high monocyte percentage and absolute count are not typical of MDS.
  • Lymphoma (e.g., Hodgkin Lymphoma): The patient's low WBC count and left shift could be indicative of lymphoma. However, the high monocyte percentage and absolute count are not typical of lymphoma.
  • Paroxysmal Nocturnal Hemoglobinuria (PNH): The patient's pancytopenia and thrombocytopenia could be indicative of PNH. However, the presence of a high monocyte percentage and absolute count is not typical of PNH.