About the Condition
Spur cell anemia is an acquired Coombs-negative nonimmune hemolytic anemia occurring in patients with liver cirrhosis (usually alcoholic) and characterized by the presence of increased numbers of spur cells (also called acanthocytes) on the peripheral blood smear. It is caused by an excess of membrane cholesterol in red blood cells and portends a very poor prognosis.
Spur cell anemia is reported in about 3% of patients with alcohol use disorder and advanced liver disease.
In patients with severe liver disease there is an imbalance in hepatic lipid metabolism resulting in excess cholesterol in red cell membranes and an increased ratio of cholesterol to phospholipid. The imbalance between cholesterol and phospholipids alters the shape and membrane fluidity of the erythrocytes as well as the capacity of the erythrocytes to repair the defect in the lipid content of their membranes. These abnormal RBC undergo splenic conditioning by splenic macrophages and are further deformed into spur cells, which are prone to destruction and hemolysis.
When normal red blood cells are transfused into patients with advanced alcohol-related cirrhosis, they are transformed into spur cells.
There are no consensus diagnostic criteria for spur cell anemia.
Suspect diagnosis of spur cell anemia in patients with:
- Liver disease, usually late stage and often progressive with:
- Severe hemolytic anemia requiring frequent RBC transfusions.
Confirm diagnosis by demonstrating spur cells (acanthocytes) on the peripheral smear:
- Spur cells (acanthocytes) are abnormal red cells with irregular surfaces and spike-like projections that vary in width, length and distribution.
- There is no agreed upon threshold in number of spur cells required for diagnosis. It varies between >5% and >20%.
Differential diagnosis of anemia in patients with cirrhosis includes (but is certainly not limited to):
- Poor nutritional status
- Gastrointestinal blood loss
- Vitamin B12 and/or folate deficiency
- Chronic inflammation
- Ineffective erythropoiesis due to bone marrow suppression (resulting from direct toxic effect of alcohol or from humoral inhibitors of erythroid progenitor cells)
- Blunted erythropoietin (epo) response to anemia
- Characterized by:
- Hemolytic anemia
- Alcohol-related steatohepatitis
- Believed to represent a variant of spur cell anemia.
- However, in contrast to spur cell anemia:
- Hemolytic anemia is usually mild
- Self-limited within days
- Might be accompanied by fever and abdominal pain (especially right upper quadrant)
Treatment of spur cell anemia is largely supportive, primarily with red cell transfusions and folic acid supplementation.
Limited evidence of medical management including:
- Intravenous administration of phospholipids
- Flunarizine (a calcium antagonist not available in the United States)
- Combination therapy of flunarizine, pentoxifylline, and cholestyramine
Orthotopic liver transplantation is the only curative treatment.
Prognosis of patients with SCA is very poor, with the majority of patients dying within months of diagnosis (from advanced liver disease, not from the anemia per se).