Pyrexia of unknown origin
Children having fever >38.3 C prolonged of at least 8 days duration and initial 3-7 days of hospital or outpatient; history and physical examination and basic investigations as CBC,ESR, x ray,urine test,stool,test, within this 8 days, without reaching to the diagnosis for the source or the cause of fever, are considered as having PUO. About 5-15% of cases with fever considered as having PUO. PUO is usually caused by common problems but with unusual presentations.Aetiology;
The most common causes are
1.infections 30-40%
2. malignancy 20-30%,As Leukemia, Lymphoma, solid tumors, Willm and neuroblastoma, bone tumors
3.connective tissue disorders 10-15% AS juvenile rheumatoid arthritis, SLE.
Miscellaneous causes;
l. drug fever
2.Kawasaki disease
3.HIV
4.Infamatory bowel disease
5. Factitious fever (MAUNCHAUSEN OF PROXY).
INFECTIONS INCLUDES
BACTEREMIA IN CHILDREN UNDER 2 YEAR
UTI, rare to be the cause as easy to diagnose it
INFECTIVE ENDOCARDITIS
CAT SCRACH DISEASE
TUBERCULOSIS
EB-VIRUS INFECTION
TYPHOID FEVER
BRUCELLOSIS
SARCOIDOSIS
TULEREMIA
TOXOPLASMOSIS
-------------------------------------------------------------------------------------------------------------common suggestions of PUO or prolonged fever in children if not resolve within 3-5 days ,is to think of EB VIRUS ,KAWASAKI DISEASE, OR UTI.
Approach for diagnosis of FUO OR PUO
Good history and physical examinations are critical components of evaluation of febrile child and frequently result in detection of the underlying cause .
History
Fever characteristics as duration pattern, rigor, sweating, timing as at night in TB, and in lymphoma . its response to antipyretics and after response; how is the child appears; usually viral will be normal but in bacterial pt looks toxic and ill.
Rash
Rash may be present with fever and the study of the type of the rash as petechial or maculopapular. Bacterial or viral infection may cause maculopapular or petechial or urticarial rash or and its distribution may help us in diagnosis. Palpable purpura may be seen in vasculitis. Vesicles in viral infections.
Accompanying symptomatology;
Inflammatory or malignancy or vasculitis may result in multisystemic involvement such as cough and shortness of breath due to to carditis, pleuritis.GI symptoms CNS symptoms and joint features .
Arthralgia in joint septic infection and in leukemia and in rheumatoid arthritis, lyme disease,
Bone pain in leukemia and SLE .
GI symptoms as in Crohn disease and ulcerative colitis.
CNS features as confusion and seizures as in bacterial endocarditis, cerebral abscess, tuberculous meningitis.
Urinary symptoms as frequency and dysuria.
Poor growth and anorexia as in chronic disease opposing bacterial infection, as acute state.
Immunization status .
Drug history
Past history; as sickle cell disease increase possibility of infection.
Exposure to causative agent as travel to malarial area or contact typhoid fever
or TB patient. Or exposed to a cat scrach.
Psychological history ;incase of factitious fever mother may create the fever as by heating the thermometer, or give some drugs as she want to stay in the hospital.
Physical examination
Confirm the temperature
Toxic child is more likely to have bacterial infection. Most well appearing children do not have bacterial infection
BP,PULSE RATE ,RR,ARE CRUCIAL FOR THE STASTUS OF THE PATIENT.
COMPLETE PHYSICAL EXAMINATION FOR LYMPHNODES AND APPEARANCE AND PALLOR AND SKIN AND NAIL AND ORGANOMEGALY AND ABDOMEN ,CVS,RESPIRATORY S,CNS,LOCOMOTOR SYSTEM., WILL NARROW THE LIMIT OF POSSIBLE CAUSES FOR THE FEVER.
INVESTIGATIONS
More extensive lab investigations are needed like blood culture,liver function ,kidney function test,thyroid function as in hyperthyroidism, ,serology for viral infections or bacterial,CTscan of abdomen or brain or the chest or pelvis, Us STUDY AND CXR. Etc…
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Most of the cases finally can be diagnosed for the cause of fever, but still few cases may not find the cause and the child remits with time called ;( Fever without source ) FWS.
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DR RIADH ALOBAIDY
ASS.PROF.COLLEGE OF MEDICINCE,MOSUL UNIV.