# Hairy Cell Leukemia: A Differential Diagnosis of Hepatitis B-Associated Aplastic Anemia and Syphilis

## TL;DR

A case shows that hairy cell leukemia, not hepatitis B or syphilis, caused a man's bone marrow failure, highlighting the need for thorough diagnosis.

## Contribution

Highlights the importance of differential diagnosis in pancytopenia cases involving hepatitis B and syphilis.

## Key findings

- Hairy cell leukemia was the true cause of bone marrow failure in a patient initially diagnosed with hepatitis B-associated aplastic anemia and syphilis.
- Failure to detect hepatitis B in hematologic malignancies can lead to fatal treatment errors.
- A detailed diagnostic plan is essential for patients presenting with pancytopenia.

## Abstract

Aplastic anemia occurs with an incidence of 2–5: 1 million people worldwide. However, the frequency of newly diagnosed cases of bone marrow aplasia is greater, and some of these patients present to emergency departments initially. Description of Case: We present the case of a middle-aged man with pancytopenia. In this case, aplastic anemia associated with hepatitis B and syphilis was only the initial diagnosis. An indolent hematologic malignancy—hairy cell leukemia—was diagnosed as the real cause of the bone marrow failure in a clinic of hematology. Conclusions: This clinical case allows us to make a conclusion, albeit not definitively, about the contribution of hepatitis B and syphilis to the clinical manifestation of hairy cell leukemia. A detailed and consistent diagnostic plan is also required in patients presenting with pancytopenia. Failure to diagnose a hepatitis B infection in a patient with malignant hematologic disease would lead to fatal therapeutic errors.