Differential Diagnosis for WBC of 14 with Normal Labs and Images

Single Most Likely Diagnosis

• Viral upper respiratory infection: A mild elevation in WBC count can be seen in response to a viral infection, which is common and often self-limiting. The normal labs and images support this diagnosis, as viral infections typically do not cause significant abnormalities in other tests.

Other Likely Diagnoses

• Bacterial pharyngitis: Although the WBC count is not markedly elevated, a bacterial infection such as strep throat could still be present, especially if the patient has symptoms like a sore throat.
• Viral gastroenteritis: Similar to a viral upper respiratory infection, viral gastroenteritis can cause a mild increase in WBC count, and the absence of other lab abnormalities does not rule out this diagnosis.
• Stress or exercise-induced leukocytosis: Physical stress or intense exercise can cause a transient increase in WBC count, which would return to normal once the stressor is removed.

Do Not Miss Diagnoses

• Leukemia or lymphoma: Although unlikely, it is crucial to consider hematologic malignancies, as they can present with a mild elevation in WBC count and normal other labs and images, especially in early stages.
• Sepsis: Early sepsis might not cause significant abnormalities in labs and images, but it is a life-threatening condition that requires prompt recognition and treatment.
• Acute appendicitis: Appendicitis can sometimes present with a mild increase in WBC count, and normal other labs and images do not rule out this diagnosis, especially if the patient has abdominal pain.

Rare Diagnoses

• Myeloproliferative neoplasms: Conditions like polycythemia vera or essential thrombocytosis can cause an elevated WBC count, but they are less common and typically have other associated lab abnormalities.
• Chronic infections (e.g., tuberculosis, endocarditis): Certain chronic infections can cause a mild, persistent elevation in WBC count, but they are less likely given the normal labs and images.
• Inflammatory or autoimmune conditions: Conditions like rheumatoid arthritis or lupus can cause an elevated WBC count, but they usually have other characteristic lab abnormalities and clinical features.