<prompt> 80 year old, asymptomatic man present with a Total Leucocyte Count of 1 lakh, with 80degA lymphocytes and 20 PMCs. What is the most probable diagnosis?HIVCMLCLLTB  <response>: Answer is C CLL Incidental finding of Lymphocytosis 80,000mcL in an elderly and asymptomatic patient suggests the diagnosis of CLL. Why is CLL the single best answer of choice here ? CLL is a disease of older patients wth 90 of cases occurring after the age of 50 years and median age of presentation is 65 years. - CMDT The patient in question is aged 80 years and hence falls in the bracket of CLL. Typical B cell CLL is often fbund incidentally when a complete blood count is done for another reason. -Harrison 16th 648 The patient in question is asymptomatic and the findings represent incidental observation on a full blood count done for an obscure reason. The hallmark of CLL is absolute lymphocytosis. White cell count is usually greater than 20,000mcL may be markedly elevated to several 100,000mcL. Usually 75-80 of circulating cells are lymphocytes. - CMDT The patient in question is presenting with a white cell count of 100,000mcL and 80 of circulating cells are lymphocytes. This finding is consistent with the blood picture of CLL. 