TEKRARLAYAN GEBELİK KAYIPLARI BULUNAN OLGUDA SAPTANAN 48,XY,+7,+21 VE 47,XX,+16 FETAL KARYOTİPLER

Öz

Erken gebelik kaybı, klinik gebeliklerin yaklaşık %10'unun sonucudur ve kromozomal anomaliler en az %50'sindeki temel nedendir. Bu yazıda ardışık düşüklerde farklı anöploidiler saptanan bir olgu üzerinden anöploidi mekanizmaları ve takipte düşünülmesi gereken seçenekler tartışılmıştır. Otuz beş yaşında kadın spontan abortus ile başvurdu. Kantitatif floresan PCR, trizomi 21 ile uyumluydu. Ancak kültür süreci sonunda yapılan karyotipleme 48,XY,+7,+21 çift trizomisini ortaya çıkardı. Olgunun takibinde başka bir düşük 47,XX,+16 olarak saptandı. Periferik kandan sitogenetik analizinde sınırda mozaik 46,XX[95]/45,X[5] karyotipi görüldü. Fizik muayenesi normaldi fakat abdominal ultrasonografide sol böbrekte çift üreter ve aksesuar dalak mevcuttu. Tekrarlayan trizomilerin olası nedenlerinden Robertsonian translokasyonlar, yapısal anomaliler veya trizomi mozaikliği dışlandı. Düşük oranlı 45,X mozaikliği ise oosit rezervini azalttığından riski arttırabilir. Olgudaki malformasyonlar mozaikliğin genitoüriner sistemde daha yüksek oranlı olabileceğini göstermektedir. Over biyopsisi invaziv doğası nedeniyle yapılamadığından bu oranının bilinmesi mümkün değildir. Tanı ve tedavi seçeneklerinin sınırlı kaldığı benzer vakaların yönetiminde genetik danışma hayati öneme sahiptir.

Anahtar Kelimeler

• Anöploidi
• Trizomi
• Tekrarlayan Düşük
• Cinsiyet Kromozom Aberasyonları

48,XY,+7,+21 AND 47,XX,+16 FETAL KARYOTYPES IN A CASE WITH RECURRENT PREGNANCY LOSS

Öz

Early pregnancy loss is the outcome of approximately 10% of clinically recognized pregnancies and chromosomal abnormalities are the underlying reason in 50%. In this report we discussed aneuploidy mechanisms and management options based on a couple with recurrent aneuploidies. Thirty-five-year-old female was referred with spontaneous abortion. Quantitative Fluorescent PCR was consistent with trisomy 21 but karyotyping revealed double trisomy of 48,XY,+7,+21. During follow-up, another abortion was diagnosed as 47,XX,+16. Peripheral blood analysis revealed a borderline mosaic 46,XX[95]/45,X[5] karyotype. Her physical examination was normal but abdominal ultrasonography revealed accessory spleen and double ureter in left kidney. We excluded Robertsonian translocations, structural aberrations or trisomic mosaicism as a cause but the borderline 45,X mosaicism may be the triggering factor by decreasing oocyte reserve. Presence of urinary malformation indicates that genitourinary mosaicism may be higher, although ovarian biopsy cannot be performed to determine it. Genetic counseling is vital in management of such cases.

Anahtar Kelimeler

• Aneuploidy
• Trisomy
• Habitual Abortion
• Sex Chromosome Aberrations

Kaynakça

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