Current Laboratory Diagnostic Approaches to Brucellosis: An Evaluation of Conventional and Molecular Methods

Abstract

Brucellosis is a zoonotic infectious disease caused by Gram-negative coccobacilli of the genus Brucella, which is endemic worldwide, particularly in the Mediterranean basin, the Middle East, Central Asia, Africa, and Latin America. Because its clinical findings are nonspecific, definitive diagnosis relies largely on laboratory confirmation. This review covers conventional methods used in the laboratory diagnosis of brucellosis (blood/bone marrow culture, Rose Bengal test, standard tube agglutination test, Coombs test, complement fixation test, ELISA) as well as molecular diagnostic methods (conventional and multiplex PCR, real-time PCR, isothermal amplification techniques, high-resolution melting analysis, CRISPR-Cas-based tests, digital PCR, next-generation sequencing, and MALDI-TOF mass spectrometry) are discussed comparatively in light of the current literature. While conventional methods have limitations such as low sensitivity, long turnaround time, and cross-reactivity, molecular methods offer higher sensitivity and specificity, shorter turnaround time, and lower biosafety risk. Consequently, it is recommended that clinical findings, conventional serological tests, and molecular methods be used together within a stepwise diagnostic algorithm to ensure a reliable diagnosis of brucellosis.

Keywords

• Brucellosis
• Brucella
• Laboratory Diagnosis
• Serological Tests
• Polymerase Chain Reaction
• Molecular Diagnosis

Brusellozda Güncel Laboratuvar Tanı Yaklaşımları: Konvansiyonel ve Moleküler Yöntemlerin Değerlendirilmesi

Abstract

Bruselloz, dünya genelinde özellikle Akdeniz havzası, Orta Doğu, Orta Asya, Afrika ve Latin Amerika'da endemik seyreden, Brucella cinsi Gram-negatif kokobasiller tarafından oluşturulan zoonotik bir enfeksiyon hastalığıdır. Klinik bulgularının özgül olmaması nedeniyle kesin tanı büyük ölçüde laboratuvar doğrulamasına dayanmaktadır. Bu derlemede brusellozun laboratuvar tanısında kullanılan konvansiyonel yöntemler (kan/kemik iliği kültürü, Rose Bengal testi, standart tüp aglütinasyon testi, Coombs testi, kompleman fiksasyon testi, ELISA) ile moleküler tanı yöntemleri (konvansiyonel ve multipleks PCR, gerçek zamanlı PCR, izotermal amplifikasyon teknikleri, yüksek çözünürlüklü erime analizi, CRISPR-Cas tabanlı testler, dijital PCR, yeni nesil dizileme ve MALDI-TOF kütle spektrometrisi) güncel literatür ışığında karşılaştırmalı olarak ele alınmıştır. Konvansiyonel yöntemlerin düşük duyarlılık, uzun sonuç süresi ve çapraz reaksiyon gibi sınırlılıkları bulunurken, moleküler yöntemler daha yüksek duyarlılık ve özgüllük, kısa sonuç süresi ve düşük biyogüvenlik riski sunmaktadır. Sonuç olarak, brusellozun güvenilir tanısı için klinik bulgular, konvansiyonel serolojik testler ve moleküler yöntemlerin birlikte, kademeli bir tanı algoritması içinde kullanılması önerilmektedir.

Keywords

• Bruselloz
• Brucella
• Laboratuvar Tanısı
• Serolojik Testler
• Polimeraz Zincir Reaksiyonu
• Moleküler Tanı

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