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The changing etiology of fever of intermediate duration

Nuria Espinosa1, Elías Cañas, Máximo Bernabeu-Wittel

  • 1Services of Infectious Diseases, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, España. nurinea@hotmail.com

Enfermedades Infecciosas Y Microbiologia Clinica
|February 16, 2010
PubMed
Abstract

Insights

Fever of intermediate duration (FID) is often caused by infections, with Q fever being the most common. Changes in causes, including the emergence of HIV infection, highlight the need for ongoing research into FID etiologies.

Area of Science:

  • Infectious Diseases
  • Internal Medicine
  • Epidemiology

Background:

  • Fever of intermediate duration (FID) is a frequent clinical presentation.
  • The primary causes of FID remain incompletely defined in many regions.

Purpose of the Study:

  • To investigate the changing etiologic spectrum of FID over time.
  • To identify the most common causes of FID in southern Spain.

Main Methods:

  • A prospective study comparing FID cases from two distinct periods (1983-1989 and 2004-2005).
  • Utilized blood cultures and serologic tests for common infectious agents (e.g., Brucella, Coxiella, Rickettsia, CMV, EBV).
  • Employed clinician-driven diagnostic approaches for further investigations.

Main Results:

  • Diagnosis was achieved in 81.1% of patients in the first period and 60.9% in the second.
  • Infectious diseases accounted for the majority of FID cases (94.8% and 84.4% respectively).
  • Q fever was the leading cause in both periods; brucellosis declined, while HIV infection emerged as a new cause in the later period.

Conclusions:

  • Q fever is identified as the predominant cause of FID in southern Spain.
  • Temporal studies are crucial for understanding evolving etiologic patterns of FID.
  • Emerging infectious agents, such as HIV, necessitate continued surveillance and research into FID causes.

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