A prospective study on the outcomes of prolonged fever and the prevalence of fever of unknown origin

A prospective study on the outcomes of prolonged fever and the prevalence of fever of unknown origin - FEBRIX

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

DRKS

Registry ID

DRKS00009591

Enrollment

168

Registered

2015-11-23

Start date

2015-12-01

Completion date

Unknown

Last updated

2025-04-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

R50

Interventions

Group 1: This is not a therapeutical study with primary/secondary endpoints. Patients will be recruited consecutively over two years from the routine outpatient clinic and will be evaluated based on a

Eligibility

Sex/Gender

All

Age

18 Years to 80 Years

Inclusion criteria

Inclusion criteria: Febrile illness exceeding 37.8°C core temperature taken orally on at least three occasions over a minimum period of one week

Exclusion criteria

Exclusion criteria: Immunodeficiency, such as HIV, neutropenia or other immunocompromised states; Nosocomial fever; Patients below 18 years of age; Patients incpable of giving consent; Pregnant women

Design outcomes

Primary

Measure	Time frame
A post-hoc analysis of clinical (history, physical examination, chest X-ray, result of the naproxen test and the 18FDG-PET/CT) markers and biomarkers (erythrocyte sedimentation rate, blood count, differential blood count, chemistry, haemostasis, thyroid hormones, blood cultures, urinalysis, biomarkers for malignancy, infection, sepsis and autoimmunity) at baseline will be performed to identify potential predictors of outcome at study entry using principal component analysis. Thus, the main analysis (multiple regression of relevant markers) will have sufficent power to identify the independent effects of the most relevant markers, which may help modify / optimise clinical approach to patients with prolonged fever as well as FUO in the future.	—

Measure

Time frame

A post-hoc analysis of clinical (history, physical examination, chest X-ray, result of the naproxen test and the 18FDG-PET/CT) markers and biomarkers (erythrocyte sedimentation rate, blood count, differential blood count, chemistry, haemostasis, thyroid hormones, blood cultures, urinalysis, biomarkers for malignancy, infection, sepsis and autoimmunity) at baseline will be performed to identify potential predictors of outcome at study entry using principal component analysis. Thus, the main analysis (multiple regression of relevant markers) will have sufficent power to identify the independent effects of the most relevant markers, which may help modify / optimise clinical approach to patients with prolonged fever as well as FUO in the future.

—

Secondary

Measure	Time frame
(1) The prevalence of "true " FUO (2) The prevalence of the underlying causes of prolonged fever (3) The Naproxen Test We will consider a complete response as a drop in body temperature to <37.2°C. (4) 18FDG-PET/CT Based on the result of an 18FDG-PET/CT, additional diagnostic clues may appear and lead to additional diagnostic tests, which may or may not lead to a diagnosis. Based on the diagnostic status at the entering of Phase #2 and the diagnostic status after conclusion of Phase #2, the increase in diagnostic utility of 18FDG-PET/CT will be determined.	—

Measure

Time frame

(1) The prevalence of "true " FUO (2) The prevalence of the underlying causes of prolonged fever (3) The Naproxen Test We will consider a complete response as a drop in body temperature to <37.2°C. (4) 18FDG-PET/CT Based on the result of an 18FDG-PET/CT, additional diagnostic clues may appear and lead to additional diagnostic tests, which may or may not lead to a diagnosis. Based on the diagnostic status at the entering of Phase #2 and the diagnostic status after conclusion of Phase #2, the increase in diagnostic utility of 18FDG-PET/CT will be determined.

—

Countries

Austria

Contacts

Public ContactDaniel Aletaha

Abteilung für Rheumatologie Medizinische Universität Wien

daniel.aletaha@meduniwien.ac.at+4314040062090

Outcome results

None listed

Source: DRKS (via WHO ICTRP) · Data processed: Feb 4, 2026