Q fever, Melioidosis, Syphilis

Question 1

Q fever

• epid/risk factors
• micro

Answer 1

Exposure to livestock

Coxiella burnetti

Question 2

Q fever - dx , treatment

Answer 2

Dx - IgG, IgM (does not grow in blood culture)
bx - doughnut-like granulomas

Tx - doxy, Bactrim, azith

Question 3

Q fever clinical presentation and cx

Answer 3

flu like illness

Cx - culture negative septic arthritis, endocarditis

Post Q fever fatigue syndrome (20%)

Question 4

Melioidosis

• epid
• micro
• RF

Answer 4

SE Asia, NT (Aus), India, China, PNG

Burkholderia pseudomallei

RF - DM, ETOH, CKD, CF

Question 5

Meliodosis clinical presentation

Answer 5

think of infections in the immunocompromised host

Acute: 
pneumonia + bacteremia/sepsis (50%)
skin abscess/ulcers
UTI like symptoms
septic arthritis or OM
encephalitis (4%)
abscesses within organs
parotitis

Chronic:
mimics TB - night sweats, haemoptysis

Question 6

Meliodosis Dx and Rx

Answer 6

Dx - culture (Ashdown’s agar)

Rx - Ceftaz or mero

Question 7

Syphilis epid and micro

Answer 7

• caused by Treponema pallidum - corkscrew shaped organism
• usually sexually acquired, can t/f in placenta
• MSM accounts for 50% of new syphilis

Question 8

Syphilis clinical presentation

1. Early
2. Secondary
3. Late
4. Neurosyphilis

Answer 8

1. Primary
   - chancre - painless genital ulcer
   - heals w/o treatment
2. Secondary
   - multiple
   - constitutional, rash etc
3. Late - asymptomatic
4. Tertiary
   - gummatous syphilis, CNS and cardiovascular involvement
5. Neurosyphilis
6. Tabes dorsalis
7. General paresis
8. Meningitis

Question 9

Neurosyphilis - Tabes dorsalis

Answer 9

Locomotor ataxia

Argyll-Robertson pupil

Question 10

Syphilis diagnostic tests

Answer 10

Non Treponemal Serology Test

• used a screening tests but high false positives in low prevalence areas
• will be negative post treatment
• ex: RPR - rapid plasma reagin

Treponemal Serology Test

• detect ab against specific antigens from TP
• will be positive for life even post treatment
• ex: Treponemal enzyme immunoassay (EIA), T pallidum particle agglutination tests (TPPA), T pallidum haemagglutination assay (THPA)

Question 11

Syphilis treatment

Answer 11

1. Early syphilis - benzathine benpen (not the usual benpen) single dose IM (doxy 2/52 if hypersensitivity)
2. Late/latent syphilis - benzathine benpen IM weekly for 3/52 (or doxy for 28/7)
3. Tertiary syphilis - benpen IV Q4H x15/7

Sexual contacts - single dose benpen IM

Question 12

Syphilis - Post treatment monitoring

Answer 12

• check treatment response with treponemal serology tests every 3, 6 and 12m
• needs to fall at least 4-fold to be considered cured, if >12m then considered treatment failure