Stomatocyte

A stomatocyte is a type of red blood cell (RBC) with a distinctive mouth-shaped (stoma) area of central pallor when viewed under a microscope. This morphological abnormality is associated with various hematological disorders and can be induced by certain conditions or substances.

Structure and Morphology

Stomatocytes are characterized by their unique shape, which deviates from the typical biconcave disc shape of normal erythrocytes. The central pallor of a stomatocyte appears slit-like or mouth-shaped, which is a result of alterations in the cell membrane's lipid bilayer. This shape change is often due to an imbalance in the lipid composition between the inner and outer leaflets of the membrane.

Causes

Stomatocytes can be seen in a variety of conditions, including:

• Hereditary stomatocytosis: A rare genetic disorder where there is a defect in the red blood cell membrane, leading to increased permeability to sodium and potassium ions.
• Liver disease: Conditions such as alcoholic liver disease can lead to the appearance of stomatocytes.
• Alcoholism: Chronic alcohol consumption can induce stomatocytosis.
• Medications: Certain drugs, such as phenothiazines and chlorpromazine, can cause stomatocyte formation.

Pathophysiology

The formation of stomatocytes is primarily due to alterations in the lipid composition of the red blood cell membrane. This can be caused by genetic mutations, as seen in hereditary stomatocytosis, or by external factors such as alcohol or drugs. The altered lipid composition affects the membrane's flexibility and stability, leading to the characteristic shape of stomatocytes.

Clinical Significance

The presence of stomatocytes in a blood smear can be an important diagnostic clue. It may indicate underlying liver disease, chronic alcoholism, or a hereditary condition. However, the presence of stomatocytes alone is not diagnostic and should be interpreted in the context of other clinical findings and laboratory results.

Diagnosis

Stomatocytes are typically identified through a peripheral blood smear examination. A trained hematologist or laboratory technician will examine the blood smear under a microscope to identify the presence and proportion of stomatocytes among other red blood cells.

Treatment

Treatment of stomatocytosis depends on the underlying cause. For hereditary stomatocytosis, management may involve supportive care and monitoring. In cases related to alcohol or drug use, cessation of the offending substance is recommended. Liver disease-related stomatocytosis may improve with treatment of the liver condition.

Also see

• Red blood cell
• Peripheral blood smear
• Hereditary stomatocytosis
• Liver disease
• Alcoholism