Examination of Cases Who Had Molecular Testing with the Presumptive Diagnosis of Cystic Fibrosis: Experience of a Single Center

Abstract

Objective: Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the Cystic Fibrosis Transmembrane Regulator (CFTR) gene, leading to multisystem involvement. Early diagnosis is crucial for managing complications and improving patient prognosis. This study aimed to evaluate the clinical and demographic characteristics and molecular analysis results of patients who underwent CFTR gene mutation analysis with a preliminary diagnosis of CF. Materials and Methods: A total of 34 patients were included in the study. Clinical and demographic data, along with genetic analysis results, were retrospectively examined. The frequency of symptoms associated with CF was determined, and the relationship between genetic findings and clinical manifestations was analyzed. Results: The most common reason for admission was respiratory symptoms, accounting for 64.7% of cases, followed by gastrointestinal complaints and malnutrition. Malnutrition was found to be significantly associated with a positive CFTR gene mutation (p=0.027). The risk of detecting a CFTR gene mutation was 5.667 times higher in patients with malnutrition. Conclusions: This study highlights the necessity of considering CF in the differential diagnosis of children presenting with recurrent respiratory tract infections and malnutrition, even in the absence of a positive family history. While respiratory symptoms were the most common reason for admission, malnutrition was found to be significantly more prevalent among mutation-positive cases. These findings underscore the importance of supporting careful clinical evaluation with genetic analysis in the diagnostic process of CF. Further large-scale, multicenter studies are needed to confirm and expand upon these results.

Keywords

• CFTR gene
• cystic fibrosis
• heterozygous mutation
• malnutrition
• recurrent lower respiratory tract infection

Kistik Fibrozis Öntanısıyla Moleküler Test Yapılan Olguların İncelenmesi: Tek Merkez Deneyimi

Öz

Giriş: Kistik fibrozis (KF), Cistic fibrosis Cystic Fibrosis Transmembrane Regulator (CFTR) genindeki mutasyonlar sonucu ortaya çıkan otozomal resesif geçişli bir hastalıktır ve multisistemik tutulum gösterir. Erken tanı, komplikasyonların yönetimi ve hasta prognozu açısından kritik öneme sahiptir. Bu çalışmada, KF ön tanısı ile CFTR gen mutasyon analizi yapılan hastaların klinik ve demografik özellikleri ile moleküler analiz sonuçlarının değerlendirilmesi amaçlandı. Materyal ve Metot: Çalışmaya toplam 34 hasta dahil edilmiştir. Klinik, demografik veriler ve genetik analiz sonuçları retrospektif olarak incelenmiştir. KF ile ilişkili semptomların sıklığı belirlenmiş ve genetik bulgular ile klinik belirtiler arasındaki ilişki analiz edilmiştir. Bulgular: Başvuru nedenleri arasında en yaygın olanı %64,7 oranıyla solunum yolu semptomlarıydı; bunu gastrointestinal şikayetler ve malnütrisyon izledi. Malnütrisyon, CFTR gen mutasyonu pozitifliği ile anlamlı şekilde ilişkili bulundu (p=0,027). Malnütrisyonu olan hastalarda CFTR gen mutasyonu saptanma riski 5,667 kat daha yüksekti. Sonuç: Bu çalışma, tekrarlayan solunum yolu enfeksiyonları ve malnütrisyon ile başvuran çocuklarda, aile öyküsü olmasa dahi, ayırıcı tanıda kistik fibrozisin mutlaka göz önünde bulundurulması gerektiğini vurgulamaktadır. Solunum semptomları en sık başvuru nedeni olmakla birlikte, malnütrisyonun mutasyon pozitif olgularda anlamlı derecede daha sık görüldüğü saptanmıştır. Bu bulgular, kistik fibrozis tanı sürecinde dikkatli klinik değerlendirmenin genetik analizle desteklenmesinin önemini ortaya koymaktadır. Bulguların doğrulanması ve genişletilmesi için daha geniş çaplı, çok merkezli çalışmalara ihtiyaç vardır.

Anahtar Kelimeler

• Kistik Fibrozis
• CFTR geni
• Heterozigot mutasyon
• Malnutrisyon
• Tekrarlayan alt solunum yolu enfeksiyonu

Kaynakça

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