Myasthenia Graviste Jitter Parametrelerinin ve Asetilkolin Reseptör Antikor Titrelerinin Korelasyonu

Öz

Amaç: Asetilkolin reseptör (AChR) antikor testi ve tek-lif elektromiyografi (TLEMG), myasthenia gravis (MG) tanısı için önemli olan iki testtir. Bu çalışmada AChR antikor titreleri ve stimülasyonlu TLEMG (STLEMG) arasında bir ilişki olup olmadığının bulunması amaçlanmıştır. Materyal ve Metot: Klinik bulguları, ardışık sinir uyarımı (ASU) ve AChR antikor testi MG ile uyumlu olan hastalar bu retrospektif kohort çalışmasına dahil edildi. Hastaların yeni tanı almış olması gerekliydi. STLEMG hastalara uygulandı ve STLEMG parametreleri analiz edildi. Bulgular: On altı hasta (11 erkek, 5 kadın) çalışmaya dahil edildi. Hastaların yaş ortalaması 54.1 ± 15.8 yıl idi. AChR antikor pozitifliği, ASU ve STLEMG parametrelerinde anormallik sırasıyla 13 (%81), 9 (%56) ve 14 (%88) hastada bulundu. Serum AChR antikor düzeyi ve artmış jitterli tek lif aksiyon potansiyel (TLAP) çiftlerinin yüzdesi arasında anlamlı pozitif bir korelasyon bulundu (p=0.019, r=0.639). Sonuç: Bu çalışma AChR antikor titreleri ve artmış jitterli TLAP çiftlerinin yüzdesi arasında pozitif bir korelasyon olduğunu göstermiştir.

Anahtar Kelimeler

• Asetilkolin reseptör antikoru
• myasthenia gravis
• stimülasyonlu tek-lif elektromiyografi

Correlation of Jitter Parameters and Acetylcholine Receptor Antibody Titers in Myasthenia Gravis

Abstract

Aim: Acetylcholine receptor (AChR) antibody test and single-fiber electromyography (SFEMG) are two important tests for the diagnosis of myasthenia gravis (MG). In this study, it was aimed to find out whether there is a relationship between AChR antibody titers and stimulated SFEMG (SSFEMG) parameters. Material and method: Patients whose clinical findings, repetitive nerve stimulation (RNS), and AChR antibody test were compatible with MG were included in this retrospective cohort study. The patients had to be newly diagnosed. SSFEMG was applied to the patients and SSFEMG parameters were analyzed. Results: Sixteen patients (11 males, 5 females) were included in the study. The mean age of the patients was 54.1 ± 15.8 years. AChR antibody positivity, abnormality in RNS and SSFEMG parameters were found in 13 (81%), 9 (56%), 14 (88%) patients, respectively. A significant positive correlation was found between serum AChR antibody level and the percentage of apparent single fiber action potential (ASFAP) pairs with increased jitter (p=0.019, r=0.639). Conclusion: This study showed a positive correlation between AChR antibody titers and the percentage of ASFAP pairs with increased jitter obtained by SSFEMG.

Keywords

• Acetylcholine receptor antibody
• myasthenia gravis
• stimulated single-fiber electromyography

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