Determination of Systemic Inflammation and Diagnostic Markers Using Iron Parameters in Foals Infected with Rhodococcus equi

Abstract

Rhodococcus equi is a significant respiratory pathogen in foals, particularly those under six months of age. This study aimed to evaluate the effects of R. equi infection on serum iron (Fe), unsaturated iron-binding capacity (UIBC), and fibrinogen (Fbg) concentrations. Fifteen foals with confirmed R. equi pneumonia and ten healthy control foals were included. Infected foals were treated with oral azithromycin and rifampicin for 15 days. Samples were collected on days 0, 7, and 14, and Fe, UIBC, and Fbg levels were analyzed. Statistical analysis showed significantly higher UIBC and Fbg levels in the infected group at the start of treatment compared to controls (p=0.004 and p<0.001, respectively). Serum Fe levels did not differ significantly between groups (p=0.138), though a trend toward lower levels in infected foals was noted, reflecting the inflammatory response. Changes in UIBC and Fbg levels reflect the progression of infection and response to treatment. Among the parameters evaluated, fibrinogen appears to be the most reliable biomarker for monitoring systemic inflammation during R. equi pneumonia in foals. However, the diagnostic value of iron parameters warrants further investigation with larger sample sizes and time-point-specific analyses.

Keywords

• Horse
• Iron
• Unsaturated Iron-Binding Capacity

Rhodococcus equi ile Enfekte Olmuş Taylarda Demir Parametreleri Kullanılarak Sistemik İnflamasyon ve Tanı Belirteçlerinin Belirlenmesi

Öz

Rhodococcus equi, özellikle altı aylıktan küçük taylarda önemli bir solunum sistemi patojenidir. Bu çalışmada, R. equi enfeksiyonunun serum demiri (Fe), doymamış demir bağlama kapasitesi (UIBC) ve fibrinojen (Fbg) düzeylerine etkisi değerlendirilmiştir. Çalışmaya, tanısı doğrulanmış ve tedavi edilen 15 tay ile sağlıklı 10 tay dahil edilmiştir. Enfekte gruptaki taylara 15 gün boyunca azitromisin ve rifampisin uygulanmıştır. Örnekler tedavi öncesi (0. gün), 7. ve 14. günlerde alınmış ve Fe, UIBC, Fbg düzeyleri analiz edilmiştir. İstatistiksel analizler sonucunda, tedavi başlangıcında enfekte taylarda UIBC ve Fbg düzeylerinin kontrol grubuna göre anlamlı derecede yüksek olduğu bulunmuştur (sırasıyla p=0,004 ve p<0,001). Serum Fe düzeyleri açısından gruplar arasında anlamlı fark gözlenmemiştir (p=0,138), ancak enfeksiyonun inflamatuvar etkisine bağlı bir azalma eğilimi izlenmiştir. ROC analizine göre Fbg, tanı açısından yüksek duyarlılık ve özgüllüğe sahip bulunmuştur. UIBC ve Fbg düzeylerindeki değişiklikler enfeksiyonun seyrini yansıtabilir. Fbg, özellikle tedavi sürecinin takibinde güvenilir bir inflamasyon belirteci olarak öne çıkmaktadır. Demir parametrelerinin tanısal değeri ise daha ileri çalışmalarla desteklenmelidir.

Anahtar Kelimeler

• At
• Demir
• Doymamış Demir Bağlama Kapasitesi

Kaynakça

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