Sibel GÖKÇAY BEK, Necmi EREN, Metin ERGÜL

Difficult Diagnosis of Myosin Heavy Chain 9 Related Platelet Disorder

Myosin Heavy Chain 9 (MYH9) missense mutations have been characterized by large platelets, leukocyte Döhle bodies, in variable extent sensorineural deafness, cataracts, and glomerulopathy. 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 since childhood. She was misdiagnosed with ITP, Bernard -Soulier and Alport syndrome chronologically. First she was treated oral methylprednisolone, then pulses of intravenous immunoglobulin (IVIG) and azathioprine 300 mg/day were tried with no response. The diagnosis was re-evaluated; bone marrow biopsy revealed increased number of megakaryocytes with decreased platelet budding, increased reticulin build-up. The audiogram revealed a profound high-frequency sensorineural hearing deficit bilaterally. Renal biopsy revealed features consistent with chronic glomerulosclerosis. MYH9 gen NM_002473.5 p.R702C (c.2104CT) heterozygous mutation was found. She has been diagnosed with MHY9 Related Disease (MHY9RD) and treated with eltrombopag 75 mg/day. After a successful increase to 17 000mm3 in platelet count, the peritoneal catheter was implanted successfully without complications. 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.

Miyozin Agir Zincir 9 Iliskili Trombosit Bozuklugu: Zor Tanı

Myosin Heavy Chain 9 (MYH9) hatalı mutasyonları, trombosit disfonsiyonları, lökosit Döhle gövdeleri, değişken ölçüde sensorinöral sağırlık, katarakt ve glomerulopati ile karakterize edilmiştir. Üçlü trombositopeni, sensörinöral işitme kaybı ve son dönem böbrek hastalığı (ESRD) olan kadın hasta sunulmuştur. 25 yaşında kadın hasta kronik trombositopeni ve üremik semptomlar ile başvurdu. Kronolojik olarak ITP, Bernard - Soulier ve Alport sendromu tanıları alan hastaya oral metilprednizolon, ardından intravenöz immünoglobulin (IVIG) ve azatioprin 300 mg / gün verildiği öğrenildi. Tanı tekrar değerlendirildi; kemik iliği biyopsisinde retikülin artışı ile megakaryosit sayısında artış izlendi. Odyogram, iki taraflı yüksek frekanslı bir sensorinöral işitme açığını ortaya çıkardı. Renal biyopside kronik glomerüloskleroz ile uyumlu özellikler saptandı. MYH9 gen NM_002473.5 p.R702C (c.2104CT) heterozigot mutasyon bulundu. MHY9 İlişkili Hastalık (MHY9RD) tanısı konulan hastaya 75 mg / gün eltrombopag ile tedavi verildi. Trombosit sayısı, 17 000 mm3'e yükseldikten sonra periton kateteri komplikasyonsuz yerleştirildi. MHY9RD, ESRD ve ciddi işitme kaybı ile karakterize nadir bir sendromdur. Böbrek biyopsisi ve invazif girişimler öncesi eltrombopag tedavisi uygulanabileceği akılda tutulmaldır.

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