Typhoid Fever vs. Brucellosis: Guidelines for Diagnosing Prolonged Fever and Systemic Infections

Typhoid fever and brucellosis are two systemic infections that present significant diagnostic challenges due to their nonspecific symptoms and similar clinical presentation. Both diseases are endemic in many regions of the world and can manifest as prolonged fever, complicating their clinical differentiation. In this article, we will explore the clinical characteristics and diagnostic tests that can assist physicians in distinguishing between these two infections.

Profundizando en el diagnóstico

Typhoid fever, caused by Salmonella enterica serotype Typhi, is characterized by fever, abdominal pain, and gastrointestinal symptoms. The diagnosis primarily relies on the detection of specific antigens in blood or blood cultures, although the latter can be slow and not always conclusive. A recent study highlighted the utility of urine antigen detection via ELISA as a promising tool for the rapid diagnosis of typhoid fever, especially in the first week of fever [1].

On the other hand, brucellosis is a zoonosis caused by species of the genus Brucella, transmitted mainly through contact with infected animals or the consumption of contaminated animal products. Symptoms include fever, night sweats, and joint pain. The diagnosis of brucellosis is complex due to the low sensitivity of blood cultures and the need for combined serological tests to avoid false-negative results. Serological tests such as serum agglutination tests and ELISA are essential for confirming the infection [2].

A comparative study in Ethiopia underscored the importance of improving laboratory services for the diagnosis of these infections, as brucellosis is often misdiagnosed as malaria or other diseases based solely on clinical presentation [3]. Furthermore, blood clot culture has proven to be more sensitive than conventional blood cultures for both diseases, allowing for a quicker identification of the etiological agent [4].

Conclusiones

The differential diagnosis between typhoid fever and brucellosis is crucial for the appropriate management of these systemic infections. The implementation of faster and more accurate diagnostic techniques, such as the use of ELISA for antigen detection and blood clot culture, can significantly improve diagnostic accuracy and timely treatment. It is essential for physicians in endemic areas to be well-informed about the clinical characteristics and available diagnostic tools for these diseases.

Referencias

• [1] Rapid diagnosis of typhoid fever by enzyme-linked immunosorbent assay detection of Salmonella serotype typhi antigens in urine.
• [2] Laboratory-based diagnosis of brucellosis--a review of the literature. Part II: serological tests for brucellosis.
• [3] Community-based prevalence of typhoid fever, typhus, brucellosis and malaria among symptomatic individuals in Afar Region, Ethiopia.
• [4] Diagnostic yield of blood clot culture in the accurate diagnosis of enteric fever and human brucellosis.

Created 6/1/2025