II. Definitions

  1. Fever
    1. Celsius Temperature >38 degrees
    2. Fahrenheit Temperature >100.4 Fahrenheit
  2. Remittent Fever
    1. Daily elevated Temperature (>38 C or 100.4 F)
    2. Returns to baseline but not to normal
  3. Intermittent Fever (Periodic Fever)
    1. Intermittently elevated Temperature (>38 C, 100.4 F)
    2. Return to baseline and to normal
    3. Examples
      1. PFAPA Syndrome: Fever every 3-4 weeks
        1. Most common cause in children age <5 years
      2. Relapsing Fever (Borrelia species): Every 2-3 weeks
      3. Malaria: Fever every other or every third day
      4. Rat Bite Fever: Fever every 3 to 5 days
      5. Hodgkin's Disease: Pel-Ebstein Fever
      6. Cyclic Neutropenia: Fever every 3 weeks
        1. Associated with Mucosal Ulcer
  4. Hectic Fever
    1. Daily elevated Temperature (>38 C or 100.4 F)
    2. Either remittent or intermittent pattern
    3. Temperature excursion >1.4 C (2.5 F)
    4. Examples
      1. Intermittent bacteremia (dental abscess, UTI)
      2. Epstein-Barr Virus
      3. Familial Mediterranean Fever
      4. Crohn's Disease
      5. Still's Disease (Juvenile Rheumatoid Arthritis)
  5. Sustained or Continuous Fever
    1. Daily elevated Temperature (>38 C or 100.4 F)
    2. Fluctuation of elevated Temperature < 0.3 C (0.5 F)
    3. Associated conditions
      1. Drug Fever
      2. Salmonella
  6. Pulse-Temperature Dissociation
    1. Pulse slower than normal for fever degree (pulse fails to increase with fever spike)
    2. Associated conditions
      1. Typhoid Fever
      2. Rickettsial infection

III. Classification

  1. Fever Without Focus
    1. Age <36 months
    2. Higher risk in younger infants
    3. Fever without localizing signs
    4. Acute onset of fever persisting <1 week
    5. Assess for Occult Bacteremia
  2. Fever of Unknown Origin (FUO)
    1. Fever exceeding 1 week duration
    2. Fever documented in the hospital
    3. All possible investigations performed during the week

IV. Special Circumstances: Fever in adults over age 65 years

  1. Fever: Temperature rise of 1.1 C (2 F) over baseline
  2. High fever suggesting severe infection: 38.3 C (101 F)

V. Causes: Common Non-Infectious Causes of Low Grade Fever

  1. Over-dressing
  2. Recent Exercise
  3. Hot weather
  4. Warm foods
  5. Recent Immunization
    1. DTP Vaccine within 24 hours
    2. MMR Vaccine within 7 to 10 days

Images: Related links to external sites (from Google)

Ontology: Fever (C0015967)

Definition (NCI) A disorder characterized by elevation of the body's temperature above the upper limit of normal.
Definition (MEDLINEPLUS)

A fever is a body temperature that is higher than normal. It is not an illness. It is part of your body's defense against infection. Most bacteria and viruses that cause infections do well at the body's normal temperature (98.6 F). A slight fever can make it harder for them to survive. Fever also activates your body's immune system.

Infections cause most fevers. There can be many other causes, including

  • Medicines
  • Heat exhaustion
  • Cancers
  • Autoimmune diseases

Treatment depends on the cause of your fever. Your health care provider may recommend using over-the-counter medicines such as acetaminophen or ibuprofen to lower a very high fever. Adults can also take aspirin, but children with fevers should not take aspirin. It is also important to drink enough liquids to prevent dehydration.

Definition (NCI) An increase in body temperature above normal (98.6 degrees F), usually caused by disease.
Definition (AIR) Fever: a documented body temperature higher than 38 degrees C., or 100.4 degrees F.
Definition (CSP) abnormal elevation of body temperature, usually as a result of a pathologic process.
Definition (MSH) An abnormal elevation of body temperature, usually as a result of a pathologic process.
Definition (NCI) The elevation of the body's temperature above the upper limit of normal, usually taken as 37.7 degrees C.
Concepts Finding (T033)
MSH D005334
ICD9 780.60
ICD10 R50.9
SnomedCT 206762007, 274234009, 64882008, 158161008, 367493005, 50177009, 386661006, 248425001
English Body temperature, increased, Fever, Fevers, Hyperthermia, Hyperthermias, Pyrexia, Pyrexias, BODY TEMPERATURE INCREASED, FEVER, Feverish, Hyperthermic, PYREXIA, TEMPERATURE ELEVATION, TEMPERATURE INCREASE, Body temperature above normal, Fever NOS, Fever, unspecified, [D]Fever NOS (context-dependent category), [D]Pyrexia (context-dependent category), [D]Fever NOS, Alteration in body temperature: hyperthermia, fever, High body temperature, Pyrexia [D], High temperature, febrile, fever, pyrexia, fever (physical finding), pyrexia (diagnosis), Increased body temperature (finding), Pyrexia [D] (situation), Body temperature increased, Temperature elevation, Pyrexia NOS, [D]Fever NOS (situation), [D]Pyrexia (situation), [D]Pyrexia, Body temperature above normal (finding), Fever [Disease/Finding], increased body temperature, increases temperature, hyperthermic, fevered, Temperature;high, temperature increase, feverish, increase temperature, raised temperature, fevers, high body temperature, temperature elevation, elevated temperature, pyrexial, Increased body temperature, Febrile, Has a temperature, Temperature raised, Temperature elevated, Pyrexial, Fever (finding), hyperthermia, febris, body temperature; increased, high; temperature, increased; body temperature, temperature; high, Feels feverish, Increased body temperature (finding) [Ambiguous], Pyrexia (finding), Pyrexia [D] (finding), high temperature
French FIEVRE, Elevation de la température corporelle, Température élevée, Pyrexie SAI, Fébrile, ELEVATION DE LA TEMPERATURE, Fievre, PYREXIE, Température augmentée, Fièvre, Hyperthermie, Pyrexie
Portuguese FEBRE, PIREXIA, Temperatura alta, Elevação da temperatura, Pirexia NE, Febril, ELEVACAO DA TEMPERATURA, Temperatura corporal aumentada, Febre, Pirexia, Doenças Febris, Enfermidades Febris, Hipertermia
Spanish FIEBRE, PIREXIA, Piréxico, Temperatura elevada, Pirexia NEOM, Elevación de temperatura, [D]pirexia (categoría dependiente del contexto), [D]fiebre, SAI (categoría dependiente del contexto), Pyrexia [D], TEMPERATURA AUMENTADA, [D]fiebre, SAI, [D]fiebre, SAI (situación), aumento de la temperatura corporal, hipertermia, [D]pirexia (situación), aumento de la temperatura corporal (hallazgo), [D]pirexia, hipertermia (hallazgo), temperatura corporal aumentada, afiebrado, febril, fiebre (concepto no activo), fiebre (hallazgo), fiebre, pirexia (hallazgo), pirexia, temperatura corporal elevada, Temperatura corporal elevada, Fiebre, Pirexia, Hipertermia, Enfermedades Febriles
German FIEBER, Temperatur hoch, fieberhaft, Temperaturanstieg, Pyrexie NNB, Fieber, nicht naeher bezeichnet, PYREXIE, TEMPERATURANSTIEG, Koerpertemperatur erhoeht, Fieber, Hyperpyrexie, Hyperthermie, Pyrexie
Italian Temperatura corporea aumentata, Febbrile, Piressia NAS, Temperatura elevata, Aumento della temperatura, Ipertermia, Piressia, Febbre
Dutch koorts NAO, temperatuur stijging, hoge temperatuur, koorts, koortsig, hoog; temperatuur, lichaamstemperatuur; verhoging, temperatuur; hoog, verhoging; lichaamstemperatuur, Koorts, niet gespecificeerd, lichaamstemperatuur verhoogd, pyrexie, Koorts, Hyperthermie, Pyrexie
Japanese 発熱NOS, 体温上昇, ハツネツNOS, コウタイオン, タイオンジョウショウ, ハツネツ, 高体温, 発熱, 熱病, 熱症状
Swedish Feber, FEBER
Czech horečka, Pyrexie NOS, Pyretický, Zvýšení teploty, Tělesná teplota zvýšená, Pyrexie, Horečka, Vysoká teplota, pyrexie, febrilní reakce
Finnish Kuume, KUUME
Norwegian FEBER
Danish Feber
Hungarian laz, Láz, Lázas, Testhőmérséklet emelkedett, Magas láz k.m.n., Pyrexia, Magas hőmérséklet, Hőmérséklet emelkedés
Korean 상세불명의 열
Croatian VRUĆICA
Hebrew xom
Polish Gorączka

Ontology: Relapsing Fever (C0035021)

Definition (MSHFRE) Infection aiguë caractérisée par des épisodes récurrents de fièvre alternant avec des intervalles asymptomatiques de rétablissement apparent. Elle est causés par des spirochètes du genre Borrelia. L'infection se transmet soit par les poux de corps (Pediculus humanus corporis, soit par des morsures de tiques molles (genre Ornithodoros)pour lesquelles les rongeurs et lagomorphes (lapins, lièvres) sont les principaux réservoirs.
Definition (MSH) An acute infection characterized by recurrent episodes of PYREXIA alternating with asymptomatic intervals of apparent recovery. This condition is caused by SPIROCHETES of the genus BORRELIA. It is transmitted by the BITES of either the body louse (PEDICULUS humanus corporis), for which humans are the reservoir, or by soft ticks of the genus ORNITHODOROS, for which rodents and other animals are the principal reservoirs.
Concepts Disease or Syndrome (T047)
MSH D012061
ICD9 087.9, 087
ICD10 A68.9 , A68
SnomedCT 186820006, 187374004, 186822003, 46107006, 420079008
English Fevers, Relapsing, Relapsing Fevers, FEVER, FAMINE, FEVER, RECURRENT, Fever, Relapsing, RELAPSING FEVER, RELAPSING FEVERS, Recurrent fever, NOS, Relapsing fever, NOS, Relapsing fever NOS, Relapsing fever, unspecified, Relapsing fever,unspecified, [X]Relapsing fever, unspecified, [X]Relapsing fever,unspecified, Recurrent fevers, recurrent fever, relapsing fever, fever recurs, recurrent fever (symptom), E-137 RELAPSING FEVERS, relapsing fever (diagnosis), Unspecified relapsing fever, FEVER RECURRENT, [X]Relapsing fever, unspecified (disorder), Relapsing fever NOS (disorder), Relapsing fevers, Relapsing Fever [Disease/Finding], fevers recurrent, Fever;relapsing, relapsing fevers, fever recurrent, fever relapsing, febris; recurrens, fever; relapsing, relapsing; fever, Relapsing fever [dup] (disorder), Relapsing Fever, Relapsing fever, Recurrent fever due to Borrelia, Relapsing fever due to Borrelia, Recurrent fever, Relapsing fever (disorder)
Spanish fiebre recidivante (trastorno), fiebre recidivante, Fiebre recurrente no especificada, fiebre recidivante por Borrelia, fiebre recurrente por Borrelia, [X]fiebre recurrente, no especificada (trastorno), [X]fiebre recurrente, no especificada, fiebre recidivante [dup] (trastorno), fiebre recurrente, SAI (trastorno), fiebre recurrente, SAI, Fiebre recurrente, Fiebre Recurrente
Dutch niet-gespecificeerde febris recurrens, febris recurrens, niet-gespecificeerd, febris; recurrens, fever; relapsing, relapsing; fever, Febris recurrens, niet gespecificeerd, febris recurrens, Febris recurrens [Relapsing fever], Febris recurrens
French Fièvre récidivante non précisée, Fièvre récurrente, non précisée, Fièvre récurrente, Spirochétose récurrente
German unspezifisches Rueckfallfieber, Rueckfallfieber, unspezifisch, Rueckfallfieber, nicht naeher bezeichnet, Rueckfallfieber, Febris recurrens, Rückfallfieber
Italian Febbre ricorrente non specificata, Febbre ricorrente
Portuguese Febre recorrente NE, Febre recorrente, Febre Recorrente
Japanese 回帰熱, 詳細不明の回帰熱, 回帰熱、詳細不明, カイキネツショウサイフメイ, カイキネツ, ショウサイフメイノカイキネツ
Swedish Återfallsfeber
Czech návratná horečka, Blíže neurčená návratná horečka, Návratná horečka, blíže neurčená, Návratná horečka
Finnish Toisintokuume
Korean 재귀열, 상세불명의 재귀열
Polish Dur powrotny, Zakażenie Borrelia recurrentis, Gorączka powrotna
Hungarian visszatérő láz, Nem meghatározott visszatérő láz, Visszatérő láz, nem meghatározott

Ontology: Continuous fever (C0424767)

Concepts Finding (T033)
SnomedCT 271751000
English sustained fever, sustained fever (physical finding), fever continuous, continuous fever, Continuous fever, Sustained fever, Continuous fever (finding)
Spanish fiebre continua (hallazgo), fiebre continua