High percentage of smudge cells in a patient with COVID19: Rediscovering their utility

Abstract

We present a patient with SARS‐CoV‐2 infection, with an unexpected presence of lymphocytosis. Examination of blood film revealed mature small lymphocytes associated with high percentage of smudge cells (63%). A peripheral flow cyometry evidenced a CD5 negative CLL. A high percentage of smudge cells is associated with CLL diagnosis and has an important prognostic value: better survival and prolonged time to first treatment. It is a useful index in developing countries with low access to molecular testing.