Stomatocytes have a mouth-shaped instead of a round area of central pallor. In many cases, stomatocytes comprise more than half of RBCs. Stomatocytosis can be heritable or acquired. If a specific genetic cause is known in the family, testing for the familial variant can be performed. Hematologist input is appropriate for any suspected heritable syndrome, any acutely ill individual, or any management considerations that depend on the underlying cause of stomatocytosis, including indications and contraindications of splenectomy, and management of iron overload. Refer to UpToDate for additional details.
RBC: red blood cell; CBC: complete blood count; MCV: mean corpuscular volume; MCHC: mean corpuscular hemoglobin concentration; MCH: mean corpuscular hemoglobin; LDH: lactate dehydrogenase; HPLC: high performance liquid chromatography; HSt: hereditary stomatocytosis; HX: hereditary xerocytosis. * Stomatocytes typically have a normal MCV and increased MCH and MCHC. ΒΆ Evidence of hemolysis may include findings from the history (jaundice, gallstones) or laboratory testing (reticulocytosis, high LDH and bilirubin, low haptoglobin). These individuals may be referred to hematology for possible osmotic fragility testing, ektacytometry, and/or genetic testing.
