Stomatocytes are red blood cells that, under a microscope, look like “kissing lips” or “coffee beans” rather than a biconcave disc with a clear centre.
A check for abnormal red blood cells is performed systematically when irregularities are found in an automated complete blood count (CBC) or when a blood smear (examination of the blood under a microscope) is specifically ordered by the doctor. Even though all possible varieties of abnormal red blood cells are checked for, unless a specific request is made, the report mentions only the abnormal varieties found in the specimen. Results are expressed as “occasional,” “a few” to “4+” (“four plus”).
The presence of stomatocytes is not specific and can be found in different forms of acquired or hereditary anemia. Sometimes they are mere artifacts associated with specimen collection and storage. A significantly high number of stomatocytes can be found in alcoholism, liver and gallbladder disease, cancer and heart disease. A high number of stomatocytes are also seen in congenital stomatocytosis and other rare hereditary diseases.