Morning cortisol — adrenal insufficiency if < 83 nmol/l
Serum protein electrophoresis
M-spike — multiple myeloma
Diagnostic Tests
Scoring Systems
HScore for hemophagocytic lymphohistiocytosis
Components scored: temperature, hepatosplenomegaly, cytopenias, ferritin, fibrinogen/triglycerides, bone marrow hemophagocytosis, known immunosuppression, AST, HIV status
HScore > 169 points — probability of HLH > 93%
Online calculator available (saintantoine.aphp.fr)
Ferritin threshold
> 10,000 mcg/l highly suggestive of HLH or Still's disease
Duke Criteria for infective endocarditis
Major criteria
Positive blood cultures with typical organisms >= 2 sets
Yucel E et al — Endocarditis in People Who Inject Drugs — JACC 2022
PMID: 35589166
Wright WF et al — NGS and Molecular Assays in FUO — Clin Infect Dis 2022
PMID: 33606012
Drug fever and inflammatory disease
Lipsky BA, Hirschmann JV — Drug Fever — JAMA 1981
PMID: 7463680
Someko H et al — Drug Fever in Nosocomial Fever — Systematic Review — Intern Med 2024
PMID: 37690845
Yaita K et al — Drug Fever During Infectious Disease Consultation — Intern Med 2016
PMID: 26984075
Elbahr U et al — FUO with ESR >= 100 mm/h — ID-IRI Cohort — Medicine 2025
PMID: 40696644
Antoniadou C et al — Fever and Inflammation of Unknown Origin in the 21st Century — Eur J Intern Med 2025
PMID: 40841245
SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.