Necmi EREN, Metin ERGÜL, Sibel GÖKÇAY BEK

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.

Difficult Diagnosis of Myosin Heavy Chain 9 Related Platelet Disorder

Myosin Heavy Chain 9 (MYH9) missense mutations have beencharacterized by large platelets, leukocyte Döhle bodies, invariable extent sensorineural deafness, cataracts, andglomerulopathy.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 chronicthrombocytopenia with since childhood. She was misdiagnosedwith ITP, Bernard -Soulier and Alport syndromechronologically. First she was treated oralmethylprednisolone, then pulses of intravenousimmunoglobulin (IVIG) and azathioprine 300 mg/day weretried with no response. The diagnosis was re-evaluated; bonemarrow biopsy revealed increased number of megakaryocyteswith decreased platelet budding, increased reticulin build-up.The audiogram revealed a profound high-frequencysensorineural hearing deficit bilaterally. Renal biopsyrevealed features consistent with chronic glomerulosclerosis.MYH9 gen NM_002473.5 p.R702C (c.2104CT) heterozygousmutation was found. She has been diagnosed with MHY9Related Disease (MHY9RD) and treated with eltrombopag 75mg/day. After a successful increase to 17 000mm3 in plateletcount, the peritoneal catheter was implanted successfullywithout complications.MHY9RD is a rare syndrome that can end with ESRD andsevere hearing loss. This rare diagnosis should be kept in mindand treatment modalities like renal biopsy should be done withEltrombopag.

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