May8 M2-Fever of Unknown Origin

Question 1

4 types of FUO

Answer 1

• classic FUO
• nosocomial FUO
• neutropenic FUO
• FUO assoc with HIV infection
• all need >38.3 on several occasions and 2+ days of microbiology

Question 2

nosocomial FUO def

Answer 2

• hospitalized, acute care and no dx of infection when admitted
• 3 days under investigation

Question 3

neutropenic FUO def

Answer 3

• ANC<500
• 3 days under investigation
• start empiric Abx coverage immediately**

Question 4

HIV associated FUO Def

Answer 4

• confirmed HIV+

- 3 days under investigation, 4 weeks as outpatient

Question 5

classic FUO

Answer 5

• all other cases with fever of at least 3 weeks

- 3 days or 3 outpatient visits or 1 week of intelligent and invasive ambulatory investigations

Question 6

(imp?) only case of FUO where you start empiric Abx

Answer 6

neutropenic FUO

Question 7

3 broad categories of causes of FUO

Answer 7

• infectious
• neoplastic
• inflammatory/CTD (connective tissue disease)

Question 8

occult infectious sources causing FUO that are still important

Answer 8

• occult abscesses
• localized (prostatitis, cholangitis, sinusitis, dental abscess)
• IE
• TB
• organisms difficult to culture
• fungal disease
• prolonged viral syndromes (EBV, CMV, HIV)

Question 9

noninfectious cause of FUO that is starting to become more prevalent

Answer 9

inflammatory and autoimmune causes (all rheumatology basically: granulomatous disease, temporal arteritis, polymyalgia rheumatica, SLE, RA, Wegener’s granulomatosis, polyarteritis nodosa, sarcoid, Crohns, FMF, TRAPS)
especially vasculitis

Question 10

other causes of FUO than inflam, neoplastic, infectious

Answer 10

• drug fever (antimicrobial, CV, chemo, CNS acting)
• tissue sources
• central peripheral regulatory disorders
• familial disease (FMF, Fabry’s)
• other (habitual hyperthermia, factitious fever = say they have it but they don’t)

Question 11

things to consider in FUO in elderly and most common thing

Answer 11

• *multisystem disease (temporal arteritis, giant cell arteritis, polymyalgia rheumatica)
• TB and mycobacterial infection
• neoplastic (colon cancer, etc.)
• thrombosis (DVT,etc.)

Question 12

most common causes of FUO in order

Answer 12

#1 lymphoma
#2 collagen VASCULAR disease
#3 abscess
#4 undiagnosed
#5 solid tumor
#6 thrombosis or hematoma
#7 granulomatous disease
#8 endocarditis
#9 mycobacterial disease

Question 13

how does FUO DDx evolve as the time of workup becomes increasingly long

Answer 13

less and less chance of infection or neoplasm

Question 14

important question to ask in history for patient with FUO

Answer 14

occupation

Question 15

(imp?) diagnostic test of highest yield, to do first in FUO

Answer 15

CT scan. 19% dx yield. good sensitivity

Question 16

(imp?) 2 things a CT scan can help identify in FUO

Answer 16

• occult intra-abdominal abscesses

- occult intra-abd neoplasms

Question 17

(imp?) 2nd most important dx test to do in FUO

Answer 17

PET scan (is the most useful nuclear medicine scan and is more useful than gallium)

Question 18

(imp?) 2 things that PET scan helps finding especially

Answer 18

• infection
• cancer
• vasculitis (very good at this one)

Question 19

disease we should always think of when seeing FUO

Answer 19

IE

Question 20

(imp?) investigation of FUO with the 3rd highest dx yield (but that is done later bc invasive)

Answer 20

liver biopsy. 15% yield.

abnormal liver enzymes or hepatomegaly DON’T indicate for a bx

Question 21

(imp?) important investigation of FUO in elderly (one of highest dx yields)

Answer 21

temporal artery bx

• 17% dx yield
• often giant cell arteritis

Question 22

(imp?) other investigations in FUO

Answer 22

• duplex doppler scan (colors) to check for DVT of lower extremities (small % of FUO)
• BM bx (very low dx yield. 1 in 500. do very late)

Question 23

worst case in FUO: tests performed without evidence

Answer 23

• empiric Abx therapy to check if get petter
• exploratory laparotomy
• markers like ESR, CRP, PCT (procalcitonin), D-dimer (bad)
• bone scan