Cat scratch disease mimicking Richter's Syndrome in a patient with chronic lymphocytic leukemia

Richter's Syndrome is a highly refractory and usually fatal condition. It occurs as a result of transformation of chronic lymphocytic leukemia (CLL) or low grade lymphoma into highly aggressive lymphoma. Patients usually present with rapidly enlarging lymph nodes and systemic symptoms like night sweats, fever and weight loss. We are reporting a case of CLL presenting with similar symptoms. Initial suspicion of Richter's Syndrome proved wrong when lymph node biopsy did not reveal evidence of high grade lymphoma. Instead it showed findings consistent with cat scratch disease (CSD), later confirmed by serology. To our knowledge this is the first reported case of CSD in a patient with CLL.