Acute fever: Difference between revisions

Latest revision as of 19:17, 5 November 2025

Background

Definition

Defined as temperature ≥38°C (100.4°F).
Peripheral temperature is not clinically accurate and central measurements are the preferred means of determining fever.
- Rectal or oral
- Rectal temperatures should not be performed in neutropenic patients^[1]

Clinical Features

Fever directly causes an increase in:^[2]
- Heart rate: 10 beats per minute per degree centigrade
- Respiratory rate

Differential Diagnosis

Fever

Infectious

Critical
- Sepsis
- PNA with respiratory failure
- Peritonitis
- Meningitis
- Cavernous Sinus Thrombosis
- Necrotizing Fasciitis
Emergent
- PNA
- Peritonsillar Abscess
- Retropharyngeal Abscess
- Epiglottitis
- Endocarditis
- Pericarditis
- Appendicitis
- Cholecystitis
- Diverticulitis
- Intra-abdominal abscess
- Pyelonephritis
- Tubo-ovarian abscess
- Encephalitis
- Brain abscess
- Cellulitis
- Abscess
- Malaria
Non-emergent
- Viral syndrome
- Otitis Media
- Sinusitis
- Pharyngitis
- Influenza
- TB
- UTI
- Epididymitis
- Prostatitis

Non-infectious

Critical
Emergent
- CHF
- Dehydration
- Recent Seizure
- Sickle Cell Dz
- Transplant rejection
- Pancreatitis
- DVT
- Serotonin Syndrome
Non-emergent
- Drug fever (except as in NMS and Serotonin Syndrome)
- Malignancy
- Gout
- Sarcoidosis
- Crohn's Disease
- Postmyocardiotomy syndrome
- Sweet's syndrome

DDx by Heart Rate

Every 0.55°C increase in temperature should → increase HR by ~10BPM

If patient has relative bradycardia, consider:
- Concomitant medication
- Drug fever
- Typhoid Fever
- Brucellosis
- Leptospirosis
If patient has frank bradycardia, consider:
- Rheumatic Fever
- Lyme Disease
- Viral Myocarditis
- Endocarditis

Evaluation

See individual notes for specific workup:

Management

Consider tylenol or ibuprophen for fever relief
Treat the underlying condition

Disposition

Depends on underlying etiology

External Links

References

↑ Niven DJ, Gaudet JE, Laupland KB, Mrklas KJ, Roberts DJ, Stelfox HT. Accuracy of Peripheral Thermometers for Estimating Temperature: A Systematic Review and Meta-analysis. Ann Intern Med. 2015;163(10):768-777. doi:10.7326/M15-1150.
↑ Davies P, Maconochie I. The relationship between body temperature, heart rate and respiratory rate in children. Emerg Med J. 2009 Sep;26(9):641-3. doi: 10.1136/emj.2008.061598.

Authors:

[1] Niven DJ, Gaudet JE, Laupland KB, Mrklas KJ, Roberts DJ, Stelfox HT. Accuracy of Peripheral Thermometers for Estimating Temperature: A Systematic Review and Meta-analysis. Ann Intern Med. 2015;163(10):768-777. doi:10.7326/M15-1150.

[2] Davies P, Maconochie I. The relationship between body temperature, heart rate and respiratory rate in children. Emerg Med J. 2009 Sep;26(9):641-3. doi: 10.1136/emj.2008.061598.

[1]

[2]

@@ Line 1: / Line 1: @@
-*[[Acute Fever (DDx)]]
+==Background==
-*[[Fever (Peds)]]
+===Definition===
+*Defined as [[Celsius Fahrenheit Temperature Conversion|temperature]] ≥38°C (100.4°F).
+*Peripheral temperature is not clinically accurate and central measurements are the preferred means of determining fever.
+**Rectal or oral
+**Rectal temperatures should not be performed in neutropenic patients<ref>Niven DJ, Gaudet JE, Laupland KB, Mrklas KJ, Roberts DJ, Stelfox HT. Accuracy of Peripheral Thermometers for Estimating Temperature: A Systematic Review and Meta-analysis. Ann Intern Med. 2015;163(10):768-777. doi:10.7326/M15-1150.</ref>
+==Clinical Features==
+*Fever directly causes an increase in:<ref>Davies P, Maconochie I. The relationship between body temperature, heart rate and respiratory rate in children. Emerg Med J. 2009 Sep;26(9):641-3. doi: 10.1136/emj.2008.061598.</ref>
+**Heart rate: 10 beats per minute per degree centigrade
+**Respiratory rate
+==Differential Diagnosis==
+{{Acute Fever DDX}}
+===DDx by Heart Rate===
+''Every 0.55°C increase in temperature should → increase HR by ~10BPM
+*If patient has relative bradycardia, consider:
+**Concomitant medication
+**Drug fever
+**[[Typhoid Fever]]
+**Brucellosis
+**[[Leptospirosis]]
+*If patient has frank bradycardia, consider:
+**[[Rheumatic Fever]]
+**[[Lyme Disease]]
+**Viral Myocarditis
+**[[Endocarditis]]
+==Evaluation==
+See individual notes for specific workup:
+*[[Fever and Rash]]
+*[[Fever of Unknown Origin]]
+*[[Neutropenic Fever]]
+*[[AIDS Fever of Unknown Origin]]
+*[[Heat Emergencies]]
+*[[Fever in Traveler]]
+==Management==
+*Consider [[tylenol]] or [[ibuprophen]] for fever relief
+*Treat the underlying condition
+==Disposition==
+*Depends on underlying etiology
+==See Also==
+*[[Pediatric fever of uncertain source]]
+*[[Fever and rash]]
+*[[Fever of unknown origin]]
+*[[Neutropenic fever]]
+*[[AIDS fever of unknown origin]]
+*[[Environmental heat diagnoses]]
+*[[Fever in traveler]]
+==External Links==
+==References==
+<references/>
+[[Category:ID]]