A case of chronic lymphocytic leukaemia with initial symptoms of cognitive impairment

Background: Chronic lymphocytic leukaemia (CLL) is a type of leukaemia that is often ignored in the initial stages. Slight fever, fatigue and night sweats are common presentations, but cognitive decline is rare. Case presentation: A 69-year-old patient with early-stage CLL presented with rapid cognitive decline. The patient was taken by his wife to seek medical attention in our hospital. In his medical reports from other hospitals, the Mini-mental State Examination(MMSE) score was 10, and the Montreal Cognitive Assessment(MoCA) score was zero since he could not cooperate. MRI revealed bilateral hippocampal atrophy. The apolipoprotein E (APOE) gene test revealed that his genotype was e3/e4. A blood test also revealed high leucocyte and lymphocyte counts. Peripheral blood lymphocyte immunotyping was subsequently performed, and the results revealed abnormal monoclonal mature B cells. The final diagnosis was CLL. Discussion: To our knowledge, memory loss is rare in the primary phase of CLL. However, we linked this patient’s cognitive impairment with CLL.