MYH9-related diseases in the differential diagnosis of chronic immune thrombocytopenic purpura

Year 2024, Volume: 37 Issue: 2, 256 - 258, 31.05.2024

Simge Horoz Bicer Mehmet Fatih Orhan

https://doi.org/10.5472/marumj.1487461

Abstract

Myosin heavy chain 9 (MYH9)-related platelet disorders (MYH9-RD) belong to the group of inherited thrombocytopenias
characterized by giant platelets and Döhle bodies. The process leading to the diagnosis of MYH9-RD in a 13-year-old male patient,
followed by the diagnosis of chronic immune thrombocytopenic purpura (ITP), is described. The patient had thrombocytopenia
with increased mean platelet volume since he was a little boy. Low CD41, CD42 and CD61 levels were detected in blood tests sent to
complete missing diagnostic tests. Platelet aggregation tests were also abnormal. The requested genetic test revealed a heterozygous
mutation in the MYH9 gene. The patient’s audiogram and kidney functions were normal. In conclusion, because MYH9-RD appears
to be rare, it is of great importance to maintain a high index of suspicion when managing patients diagnosed with chronic ITP.
Additional complaints and findings should be considered at every outpatient clinic examination to make a more accurate diagnosis
and prevent unnecessary treatments.

Keywords

Thrombocytopenia , Chronic ITP , MYH9 , Mean Platelet Volume , Children

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