A systematic review of ABCG8 mutation and sitosterolemia.

BACKGROUND

Sitosterolemia is a rare inherited condition caused by elevated levels of plant sterols in the plasma, characterized by mutations in ABCG5 and ABCG8 genes. A scarce occurrence in this condition are hematological abnormalities such as hemolytic anemia, stomatocytosis, and macrothrombocytopenia. We conducted a meta-analysis and systematic review to answer these questions regarding patients who have hemolytic anemia and ABCG8 mutation.

METHODS

13 reports were shortlisted for the final analysis (Observational studies-6, case series-4, case reports-3). Descriptive statistics were utilized to study the patient characteristics.

RESULTS

From the 13 reports that we found in available literature, we identified 19 cases of ABCG8 mutation and anemia. From the random-effects proportions model, the chance of this event occurring among patients with sitosterolemia was 6.8% [0.068, 95% Confidence Interval (CI) 0.016-0.120, P=0.010] (I2 24.68%) (14/145). Thrombocytopenia and stomatocytosis were frequently reported. Splenomegaly and xanthomas were other common associations.

CONCLUSIONS

To the best of our knowledge, we provide the first report of the prevalence of anemia, specifically in patients with sitosterolemia caused by a mutation in the ABCG8 gene. At 6.8%, this is an extremely rare occurrence in an already infrequent disease.