S BEK1, N EREN1
1Kocaeli University Hospital, Kocaeli, Turkey
Background: Myosin Heavy Chain 9 (MYH9) missense mutations have been characterized by large platelets, leukocyte Döhle bodies, in variable extent sensorineural deafness, cataracts, and glomerulopathy. We report the clinical manifestations and treatment of a case with heterozygous MYH9 R702 mutation.
Case Report: A 25-year old female with triad of thrombocytopenia, sensorineural hearing loss and end stage renal disease (ESRD) presented with uremic symptoms with a history of chronic thrombocytopenia with recurrent epistaxis, gum bleeding and anemia since childhood. She was misdiagnosed with ITP, Bernard -Soulier and Alport’s syndrome chronologically. First misdiagnosis of idiopathic thrombocytopenia was treated oral methylprednisolone, then pulses of intravenous immunoglobulin (IVIG) and azathioprine 300 mg/day were tried respectively with no response. The diagnosis was re-evaluated; bone marrow biopsy was done relieving increased number of megakaryocytes with moderately decreased platelet budding and increased reticulin build-up. Large platelets and Döhle bodies on peripheral blood smear were noted. The audiogram done at the age of 22 revealed a profound high-frequency sensorineural hearing deficit bilaterally and the renal biopsy was done with 3 gr/day proteinuria. Renal biopsy revealed features consistent with chronic glomerulosclerosis. Genetic analysis was performed at the age of 23 revealing MYH9 gen: NM_002473.5 p.R702C (c.2104C>T) heterozygous mutation. She has no findings of cataract on examination. She has been diagnosed with MHY9 Related Disease (MHY9RD) and treated with eltrombopag 75 mg/day. After a successful increase to 17 000/mm3 in platelet count, the peritoneal catheter was implanted successfully without complications.
Conclusions: MHY9RD is a rare syndrome that can end with ESRD and severe hearing loss. This rare diagnosis should be kept in mind and treatment modalities like renal biopsy should be done with eltrombopag.
I am an assistant professor in Kocaeli University Hospital and will be working for one-year in Sydney University, Nephrology Department as an ISN-fellow between 1st June- 2018/ 2019.