Pyrexia of unknown origin

Emergency referrals

Consider urgent referral for patients with the following:

  • Altered conscious level
  • Suspicion of meningitis
  • Suspicion of endocarditis
  • A PUO, (see criteria below) especially if the patient is unwell, would be grounds for urgent referral through Emergency. It is likely that most patients fitting this description would be admitted through Emergency for investigation. Do not delay urgent referral if the patient is unwell or deteriorating. If in doubt contact the ID registrar/specialist for advice.

Pyrexia of unknown origin (PUO) is defined as:

  • Temperature greater than 38.3℃ on several occasions
  • Accompanied by more than 3 weeks of illness
  • Failure to reach a diagnosis after 1 week of investigation

Most patients with PUO will be referred urgently through Emergency. If in doubt how to refer this condition contact the Infectious Diseases registrar at your local hospital or an Infectious Diseases physician.

Other important information for referring practitioners

Medical management

Most are caused by uncommon presentations of common diseases e.g. tuberculosis, endocarditis, gall bladder disease or HIV.

In adults

  • Infections and cancer (25-40%)
  • Autoimmune disorders (10-20%)

Specific causes

  • Infection
    • Bacterial (hepatobiliary, occult abscess, osteomyelitis, brucellosis, treponemal disease, gonococcal disease)
    • Viral (CMV, EBV, HIV)
    • Fungal
    • Parasitic (toxoplasma, trypanosomiasis, leishmania, amoeba
    • Rickettsial infection (Coxiella burnetii)
    • Chlamydial (esp psittacosis)
  • Cancer
    • Lymphomas, renal cell carcinoma, malignant histiocytosis
  • Autoimmune disease (Juvenile RA, polyarteritis nodosa, MCTD
  • Drugs ( beta lactam antibiotics, isoniazid)
  • Other (granulomatous disease, vasculitides, PE, familial Mediterranean fever, hyperthyroidism)

If the cause of a fever is not immediately apparent, take a full history. Consider:

  • Foreign travel, contact with foreign visitors,
  • Occupational exposure
  • Look for evidence of immunosuppression
  • Recent opportunistic infections
  • High risk behaviour ( IV drug use)

Examine closely for:

  • Lymphadenopathy
  • Check ENT
  • Examine skin for rashes
  • Check nails for splinter haemorrhages
  • Auscultate for murmurs
  • Examine the chest
  • Examine abdomen for masses, tenderness
  • Check testes and prostate in men
  • Perform pelvic examination in women

Perform first round investigations using broad screening tools (FBC, E/LFT, ESR, CRP, 2 sets of blood cultures from separate sites & CXR). Only use specific investigations when guided by suspicion from history or examination.

Refer urgently if patients condition is progressive and further investigation may delay management.

Referral requirements

A referral may be rejected without the following information.

  • Presence of any red flags
  • Timeline of symptoms
    • Maximum recorded temperature
    • Any diurnal variation
    • Associated symptoms (rigors, sweating, dysuria, rash, diarrhoea, vomiting)
    • Duration
  • Excluded causes
  • List foreign travel
  • Contact with animals
  • Occupation
  • Drug history including non-prescription and recreational
  • Sexual history
  • Examination
    • Lymphadenopathy
    • Rashes (full description)
    • Heart murmur
    • Joint inflammation
    • Neurological signs
    • Fundoscopy findings
  • Investigations
    • FBC, ESR, CRP, E/LFTs
    • ANA, Rh Factor and TFT
    • Sputum culture
    • MSU micro C&S
    • HIV serology
    • CXR
    • Echocardiogram if heart murmur present

Additional referral information (useful for processing the referral)

  • Auto antibody screen
  • Relevant serology (EBV, toxoplasma, CMV, pertussis, hepatitis B and C etc)
  • Blood cultures (at least two sets taken from separate sites)
  • Skin biopsy results of any rash

Out of catchment

Metro North Health is responsible for providing public health services to the people who reside within its boundaries. Special consideration is made for patients requiring tertiary care or services that are not provided by their local Hospital and Health Service. If your patient lives outside the Metro North Health area and you wish to refer them to one of our services, inclusion of information regarding their particular medical and social factors will assist with the triaging of your referral.

  • Impact on employment
  • Impact on education
  • Impact on home
  • Impact on activities of daily living
  • Impact on ability to care for others
  • Impact on personal frailty or safety
  • Identifies as Aboriginal and/or Torres Strait Islander
  • To establish a diagnosis
  • For treatment or intervention
  • For advice and management
  • For specialist to take over management
  • Reassurance for GP/second opinion
  • For a specified test/investigation the GP can’t order, or the patient can’t afford or access
  • Reassurance for the patient/family
  • For other reason (e.g. rapidly accelerating disease progression)
  • Clinical judgement indicates a referral for specialist review is necessary
  • Presenting symptoms (evolution and duration)
  • Physical findings
  • Details of previous treatment (including systemic and topical medications prescribed) including the course and outcome of the treatment
  • Body mass index (BMI)
  • Details of any associated medical conditions which may affect the condition or its treatment (e.g. diabetes), noting these must be stable and controlled prior to referral
  • Current medications and dosages
  • Drug allergies
  • Alcohol, tobacco and other drugs use
  • Full name (including aliases)
  • Date of birth
  • Residential and postal address
  • Telephone contact number/s – home, mobile and alternative
  • Medicare number (where eligible)
  • Name of the parent or caregiver (if appropriate)
  • Preferred language and interpreter requirements
  • Identifies as Aboriginal and/or Torres Strait Islander
  • Full name
  • Full address
  • Contact details – telephone, fax, email
  • Provider number
  • Date of referral
  • Signature
  • Willingness to have surgery (where surgery is a likely intervention)
  • Choice to be treated as a public or private patient
  • Compensable status (e.g. DVA, Work Cover, Motor Vehicle Insurance, etc.)
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