Fever that is prolonged

Question 1

Probability diagnosis

Answer 1

Pyogenic abscess (anywhere e.g. liver, pelvis)

Pneumonia (viral, bacterial, atypical)

Epstein–Barr mononucleosis

Viral upper respiratory tract infection

Urinary infection (incl. chronic pyelonephritis)

Question 2

Serious disorders not to be missed

Answer 2

Vascular:vasculitides

• polyarteritis nodosa
• giant cell arteritis
• polymyalgia

Infection:

• HIV/AIDS
• malaria and other tropical diseases
• zoonoses (e.g. leptospirosis, Q fever, listeriosis)
• typhoid/paratyphoid fever
• tuberculosis
• osteomyelitis
• chronic septicaemia/bacteraemia
• infective endocarditis
• Lyme disease
• Syphilis (secondary)

Cancer:

• lymphoma and leukaemia
• solid cancers (e.g. lung, kidney)
• disseminated

Other:

• inflammatory bowel disease (e.g. Crohn)

Question 3

Pitfalls (often missed)

Answer 3

Up to 20% remain unknown.

FUO is fever > 38.3°C for at least 3 weeks.

Connective tissue disorder e.g.

• rheumatoid arthritis
• SLE

Sarcoidosis

Drug idiosyncrasies

Rarities:

• factitious fever

Question 4

Key history

Answer 4

PMH

• occupation
• travel history
• sexual history
• IV drug use (leads to endocarditis and abscesses)
• animal contact,
• medication
• other relevant factors.

Enquire about associated symptoms such as;

• pruritus
• a skin rash
• abdominal pain and diarrhoea
• weight loss.

Note the fever pattern.

The history may need to be repeated.

Question 5

Key examination

Answer 5

Note general features and vital signs

Check;

• skin (rash, vesicles or nodules)
• eyes
• temporal arteries
• sinuses
• teeth and oral cavity
• heart (note any murmurs)
• lungs, abdomen (enlarged or tender liver, spleen, kidney)
• rectal and pelvic examination
• lymph nodes (esp. cervical)
• urinalysis.

Question 6

Key investigations

Answer 6

The basics are:

• FBE
• ESR/CRP
• CXR and sinus films
• urine MC
• routine blood chemistry
• LFTs
• blood culture.

Other tests depend on clinical pointers e.g.

• specific organisms
• lymph node biopsy
• HIV
• tuberculosis
• connective tissue auto-antibodies

Question 7

Diagnostic tips

Answer 7

Prolonged fever is usually an uncommon presentation of a common disorder (unless recent travel, esp. to tropics).

Fever in the elderly is sepsis until proved otherwise (esp. lungs and urinary tract).

The diagnosis of septicaemia can be easily missed, esp in;

• small children
• the elderly
• the immunocompromised.