ChemPath: PUO Flashcards
Defined criteria commonly accepted definition of PUO
Durack and Street criteria
- Temperature >38.3
- Duration >3weeks
- Evaluation in at least 3 outpatient visits / 3 days hospital
What are the categories of PUO under the Durack and Street criteria?
What are the causes of classic PUO?
- Infection
- Malignancy
- Collagen vascular disease
What are the causes of nosocomial PUO?
- C. difficile enterocolitis
- Drug-induced
- Pulmonary embolus
- Septic thromboplebitis
- Sinusitis
What are some causes of immune deficient (neutropenic) PUO?
- Opportunistic bacterial infection
- Fungi - aspergillosis, candidiasis
- Herpes virus
What are some causes of HIV-associated PUO?
- CMV
- Mycobacterium avium-intracellulare complex
- Pneumocystis carinii pneumonia
- Drug-induced
- Kaposi sarcoma
History points for PUO
- B Symptoms (FLAWS), localising symptoms
- Medications - doses & initiation date
- Contact history - pets / animals
- Drug use
- Sexual history
- Foreign travel
Points to ask on Hx of foreign travel
- Specific Village/ City?
- What they did there
- Where they stayed
- Others infected?
- Walking barefoot?
- Mosquito Nets
Test to consider in all PUO
- HIV (consent needed)
- Exclude malaria in patient with tropical travel in last 2 years
What investigations for PUO?
Any others - speak to consultant (money)
What is the first line test in diagnosis of acute EBV infection?
Serum EBV IgM
What imaging and tissue diagnositic techniques might you employ in PUO?
Imaging
- FDG-PET (?cancer)
- Echocardiogram
Tissue
- Biopsy
- LP
- Bone marrow aspiration
When to order Echocardiogram in PUO?
?Infective Endocarditis - when the patient meets the Duke Criteria (2 major or 1 Major + 3 minor)
Describe the Duke Criteria for infective endocarditis.
What is required for diagnosis?
What are some infective causes of PUO?
How to order tests for infective PUO
REFER TO RIPL (rare and imported pathogens laboratory) - include discriminating characteristics e.g. Indian man, swimming in freshwater…
Describe the diagnostic criteria for Adult-onset Still’s disease
List 2 clinical features of Adult-onset Still’s
- Salmon pink rash - can be mistaken for drug-induced rash
- Ferritin often very high in Adult-onset Still’s (macrophage activation syndrome)
What are some clinical features of GCA?
- Age > 50
- Headache
- Jaw claudication
- 50% have vision changes
- High risk of blindness/stroke
How is GCA diagnosed and managed?
Diagnosis
- Blood ESR > 45 (needs to be age adjusted)
- Temporal artery biopsy (gold standard)
Managment
- High-dose prednisolone immediately
- Refer to rheumatology and opthalmology
Malignant causes of PUO
- Lymphoma (esp. non-Hodgkins) - raised LDH, weight loss, lymphadenopathy
- Leukamia - bone marrow biopsy
- Renal Cell Carcinoma - 20% present with fever, haematuria can occur
- Hepatocellular carcinoma or liver metastases
What are is the most common miscellaneous cause of PUO?
Drug-induced
- 1/3 of hospitalised patients suffer form adverse drug reactions, including ‘drug fever’
- This can be an idiosyncratic reaction or because the drug affects thermoregulation
- Eosinophilia and rash accompany drug fever in 25%
Conditions that require URGENT (preconfirmation) treatment
- Infective endocarditis
- Disseminated TB (FLAWS)
- CNS TB (headache / reduced GCS)
- GCA
- SEPSIS
Which causes of PUO should you think of when ferritin is very high?
Adult-onset Still’s disease
How would you diagnose active TB?
Sputum culture - gold standard but slow
IGRA is not diagnostic of active TB
