[Clinical Picture] When leukaemia masquerades: the hidden syphilis diagnosis

A 61-year-old man with chronic lymphocytic leukaemia maintained on oral venetoclax 400 mg daily presented to the emergency department with oral lesions, worsening lymphadenopathy, and fevers. CT showed multiple enlarged submandibular and submental lymph nodes, and fine needle aspiration with flow cytometry demonstrated a predominantly lymphocytic population positive for CD19 with co-expression of CD5 and variable CD23 expression and lambda light chain restriction consistent with chronic lymphocytic leukaemia involving a lymph node.