PUO

Question 1

define PUO

Answer 1

Durak definition

prescriptive set of mandatory ix
3 days of hospital Ix or 3 outpt apts

classic - most common
nosocomial - healthcare associated

causative agents different depending on whether got PUO from community or hospita;l

Question 2

reasons for PUO

Answer 2

1/4-1/3 of PUI is infection

In most recent - the most common reason is no dx - because have more people with bad immune system so more cases of PUI with unknown origin

children more due to infection

Question 3

causes of PUO in HIV pts

Answer 3

CD4 cell count dependent
high risk TB/NTM
PCP
cryptococcal meningitis
non-hodgekin’s lymphoma

Question 4

causes of PUO in patients with neutropenia

Answer 4

underlying disease
fungal infection

Question 5

hx for PUO

Answer 5

B-symptoms, localising symptoms
Medications - doses and initiation date
Contact history, pets / animal exposures
Injecting drug use, sexual history
Foreign travel - need to be specific

Question 6

initial ix for PUO

Answer 6

stool OCP - ovum cysts and parasites
TFTs - thyroiditis can be a cause of PUO

Question 7

Which would be the most useful test in confirming acute EBV infection
2 weeks after possible exposure in an immunocompetent patient

Answer 7

EBV IgM

Timeline for IgM going up or down - up by 2wks after infection, and stay up for 2more weeks and then come down
IgG - comes up by 2-3wks - sometimes takes 4 wks - then stays +ve for life.

Question 8

what is a heterophile test

Answer 8

looks for something like EVB or CMV causing lymphocytes look weird

Question 9

further ix for PUO if have good reason

Answer 9

• FDG-PET CT scan - radiolabelled glucose - show you anatomy and metabolism
• Echocardiogram - endocarditis, use Duke’s criteria - see who gets echo
• Biopsies
• Lumbar puncture
• Bone marrow aspirate

Question 10

use of PET CT in PUO

Answer 10

• Fluoro-D-Glucose accumulates in cells with an increased rate of glycolysis
  – All activated leukocytes demonstrate increased FDG uptake
• Allows metabolic correlation to anatomical scan
• Useful in endocarditis and vascular infections / inflammation
• Caution in those with poor glucose control
• Ensure patient fasted appropriately

Question 11

use of echo for PUO

Answer 11

Duke’s criteria to see if need echo for IE:
* 2 major or 1 major + 3 minor criteria
* Major
* – Persistent bacteraemia (>2 BC pos)
* – Echocardiogram: vegetation
* – Positive serology for Bartonella, Coxiella or Brucella

• Minor
• – Predisposition (murmur, IVDU)
• – Inflammatory markers (fever , CRP high)
• – Immune complexes: splinters, RBCs in urine
• – Embolic phenomena: Janeway lesions, CVA
• – Atypical echo
• – 1 positive BC

Question 12

which test is most useful for a patient from lebanon

Answer 12

brucella serology

Question 13

what causes cryoglobinaemia

Answer 13

hep C

Question 14

viral causes of PUO

Answer 14

– CMV / EBV
– HIV
– Hepatitis A,B,C,D,E

Question 15

parastitic causes of PUO

Answer 15

– Malaria
– Amoebic liver abscess
– Schistosomiasis
– Toxoplasmosis
– Trypanosomiasis

Question 16

fungal causes of PUO

Answer 16

– Cryptococcosis
– Histoplasmosis
– Coccidioides

Question 17

bacterial causes of PUO

Answer 17

– Q-Fever, Bartonella, Brucella.
– Mycobacteria - TB/NTM
– Enteric fevers
– Zoonoses

Question 18

what is RIPL

Answer 18

rare and important pathogens lab

tell you which infections to test for

Question 19

inflammatory causes of PUO

Answer 19

autoimmune and primary inflammatory conditions have a high %
* Young patient = Adult onset Stills
* Older patient = GCA
* Involve rheumatologist
* Careful interpretation of results

Question 20

what are the criteria for Adult onset Still’s

Answer 20

5 or more criteria including 2 or more major criteria

Question 21

rash in adult onset stills

Answer 21

• Salmon Pink rash
• Can be mistaken for drug eruption / rash
• Ferritin often very high in Adult onset Stills → Macrophage activation
  syndrome

Question 22

summarise Giant cell arteritis

Answer 22

• Age >50
• Headache – Not needed for diagnosis – but should raise suspicion
• Jaw claudication
• ESR > 45
  – need to adjust for age
  – Not raised in 7-20% in case series
  – CRP adds sensitivity
• 50% will have change if vision on presentation – Often minor / fluctuating
• High risk of sight impairment / stroke
• Temporal biopsy gold standard
• PET CT useful
• Treat immediately – involve rheumatologist.

Question 23

malignant causes of PUO

Answer 23

• Lymphoma – especially non-Hodgkin’s
  – Often advanced disease with aggressive subtype
  – Raised LDH, weight loss, lymph nodes
• Leukaemia – Bone marrow biopsy
• Renal Cell Carcinoma – 20% of cases present with fever, haematuria can occur
• Hepatocellular carcinoma or other tumours metastatic to the liver
• Often identified on axial imaging

Question 24

miscellaneous causes of PUO

Answer 24

drugs
* 1/3 of patients suffer from adverse drug reactions - including drug fever
* idiosynchratic reaction or by affecting thermo reg
* eosinophiolia and rash accompany drug in only 25%

Question 25

indications for urgent PUO rx before confirmation

Answer 25