Pyrexia of unknown origin

Pyrexia of unknown origin

Pyrexia of unknown origin	PUO is defined as undiagnosed fever of more than 3 weeks duration. Careful and repeated clinical history and examination; FBC , blood film , differential WCC ; CRP or ESR ; bilirubin , ALP , AST , ALT , GGT , LD .
Bacterial infection esp	Blood culture (repeated); urine microscopy and culture ; faeces - microscopy, culture and antigen detection .
Endocarditis
Abscess esp Intra-abdominal
Ascending cholangitis	See Cholestasis .
Urinary tract infection
Osteomyelitis
Typhoid fever
Tuberculosis	Urine for mycobacteria testing ; collect early morning specimens (three).
Brucellosis
Fungal infection eg
Cryptococcal infection	Cryptococcal antigen - blood, CSF , if appropriate.
Protozoal infection eg
Malaria	Malaria parasites - blood - repeated thin and thick blood films, if indicated.
Toxoplasmosis
Viral infection eg
Cytomegalovirus infection
Infectious mononucleosis
HIV infection
Drug fever
Malignancy esp	FNAB , lesion biopsy; as appropriate. Tumour markers are unreliable as a screening test for occult malignancy.
Renal cell adenocarcinoma
Hepatocellular carcinoma
Disseminated carcinoma
Hodgkins disease Lymphoma (non-Hodgkins)
Atrial myxoma
Connective tissue diseases
Vasculitis
Granulomatous Hepatitis
Sarcoidosis
Crohns disease
Familial Mediterranean fever	Clinical diagnosis. CRP or ESR (intermittent elevation); biopsy of appropriate tissue only if clinical features suggest amyloidosis.
Occult haematoma eg
Retroperitoneal haematoma
Factitious fever