In this article, we provide an illustrated review that may serve as a microscope companion, as well as a reference for the diagnosis of red blood cells alterations and the interpretation of their significance. Beginners in the fields of clinical haematology and haematopathology may benefit from this manuscript's brevity and practical points, while the more advanced will find it useful as a teaching tool.
Platelets, along with coagulation factors and vasculature, represent the three main compartments of hemostasis. Upon investigation of a suspected hemostasis disorder, platelet count, size and morphology often offer important clues to the diagnosis or help narrow the differential diagnosis. In this review, we describe a general approach to diagnosing platelet disorders, starting with easily obtained data such as findings of complete blood count (CBC) and microscopic review of a stained peripheral blood smear. We discuss general findings that help separate consumptive from underproduction thrombocytopenia. We further touch on inherited thrombocytopenia disorders after classifying them into those associated with small, normal sized or large platelets. Illustrative microscopic images are provided where contributory. We conclude with a suggested algorithmic step-by-step approach to investigating a suspected platelet disorder in children.