A Rare Cause of Splenomegaly: Acid Sphingomyelinase Deficiency Type B

Öz

Acid Sphingomyelinase Deficiency is a rare, autosomal recessive inherited metabolic disorder caused by mutations in the SMPD1 gene. It is a pan-ethnic, multisystemic, often progressive, and potentially life-limiting condition, with an age of onset ranging from the first days of life to adulthood. Acid Sphingomyelinase Deficiency results from a deficiency of the enzyme acid sphingomyelinase. In Acid Sphingomyelinase Deficiency type B patients, hepatosplenomegaly and pulmonary pathological changes are frequently observed; however, central nervous system involvement is usually absent. The rarity of the disease and the lack of expertise often lead to misdiagnosis, delayed diagnosis, and limited access to adequate care. In recent years, enzyme replacement therapy with olipudase alfa, which provides an exogenous source of acid sphingomyelinase, has been introduced for children and adults diagnosed with Acid Sphingomyelinase Deficiency without central nervous system involvement, altering the course of the disease. In this case presentation, we aimed to emphasize the consideration of Acid Sphingomyelinase Deficiency in the etiology of splenomegaly.

Anahtar Kelimeler

• Acid Sphingomyelinase Deficiency
• interstitial lung disease
• Niemann-Pick disease
• splenomegaly
• thrombocytopenia

Nadir Bir Splenomegali Nedeni: Asit sfingomiyelinaz eksikliği tip B

Öz

Asit Sfingomiyelinaz Eksikliği, SMPD1 genindeki mutasyonlardan kaynaklanan nadir bir otozomal resesif geçiş gösteren, başlangıç yaşı yaşamın ilk günlerinden erişkinliğe kadar değişen, pan-etnik, çok nadir, multisistemik, çoğunlukla ilerleyici ve potansiyel olarak yaşamı sınırlayan bir metabolik hastalıktır. Asit Sfingomiyelinaz Eksikliği, asit sfingomiyelinaz enziminin yetersizliğinden kaynaklanır. Asit Sfingomiyelinaz Eksikliği tip-B hastalarda sıklıkla hepatosplenomegali ve akciğerlerde patolojik değişiklikler vardır, ancak genellikle santral sinir sistemi tutulumu yoktur. Hastalığın nadir görülmesi ve uzmanlık eksikliği, yanlış tanıya, teşhisin gecikmesine ve yeterli bakıma erişimin engellenmesine neden olmaktadır. Son yıllarda merkezi sinir sistemi tutulumu olmayan Asit Sfingomiyelinaz Eksikliği tanılı çocuk ve yetişkinlerde, hastalığın seyrini değiştiren, asit sfingomiyelinazın ekzojen bir kaynağını sağlayan bir enzim replasman tedavisi olan olipudaz alfa kullanıma girmiştir. Bu vaka sunumunda splenomegali etyolojisinde Asit Sfingomiyelinaz Eksikliğinin de göz önünde bulundurulmasını vurgulamak istedik.

Anahtar Kelimeler

• Asit Sfingomiyelinaz Eksikliği
• interstisyel akciğer hastalığı
• Niemann-Pick hastalığı
• splenomegali
• trombositopeni

Kaynakça

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