A woman in her 30s presented with a raised lymphocyte count of 6 × 10⁹/L during routine blood tests. A peripheral blood film was prepared to investigate the cause of the lymphocytosis. While assessing the film, an interesting phenomenon was noted, one that can influence how we interpret platelet counts in certain samples.

What do you observe? What causes it and what affect could this potentially have on the full blood count (FBC) results?

Images for this case were kindly shared by Charlotte Pattison.