Differential Diagnosis
- Single most likely diagnosis
- Viral infection (e.g. influenza) with secondary bacterial infection: The patient's recent flu-like illness, elevated WBC count, and increased platelets are consistent with a viral infection complicated by a secondary bacterial infection. The absolute lymphocyte count is slightly elevated, which can occur in viral infections, while the presence of immature granulocytes suggests a response to a bacterial infection.
- Other Likely diagnoses
- Bacterial infection (e.g. pneumonia): The elevated WBC count and presence of immature granulocytes suggest a bacterial infection, which could be a primary diagnosis or a complication of the initial flu-like illness.
- Viral infection with reactive neutrophilia: Some viral infections can cause a reactive neutrophilia, which could explain the elevated WBC count and increased platelets.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Sepsis: Although the patient's symptoms and lab results do not strongly suggest sepsis, it is a potentially life-threatening condition that must be considered, especially in the context of a recent infection.
- Neutrophilic leukemia (e.g. chronic myeloid leukemia): While unlikely, an elevated WBC count with increased immature granulocytes could be indicative of a myeloproliferative disorder, which would require prompt evaluation and treatment.
- Rare diagnoses
- Myeloproliferative neoplasm (e.g. essential thrombocythemia): The elevated platelet count could be suggestive of a myeloproliferative neoplasm, although this would be an uncommon diagnosis in this clinical context.
- Lymphoproliferative disorder (e.g. lymphoma): Although the absolute lymphocyte count is only slightly elevated, a lymphoproliferative disorder could be considered, especially if the patient has other symptoms or lab abnormalities suggestive of such a condition.