Syphilis

Question 1

What causes syphilis?

Answer 1

T pallidium

Question 2

What are the features of primary syphilis?

Answer 2

🚩1-3 week of T pallidium lands on skin
🚩local destroy of tissue 👉 syphilitic CHANCRE: painless / hard base / raised borders / covered with a fluid rich in spirochetes
🚩chancre:spontaneous heal( 3-8w)
🚩 spirochetes 👉 lymph nodes 👉lymphadenopathy👉 blood

Question 3

What are the features of secondary syphilis ( disseminated stage)?

Answer 3

🚩6 - 12 weeks after the infection
MOST INFECTIOUS STAGE
🚩 flu like symptoms
🚩spirochetemia 👉 generalized lymphadenopathy
🚩spirochetes destroy endothelium of small capillaries 👉 non itchy maculopapular rash on the trunk, arms , legs , palms & soles & mucosa
🚩 condyloma lata : smooth,warty, white painless lesions, highly infectious on : ( genitals,anal,armpits)

Question 4

What are the features of latent stage of syphilis?

Answer 4

📌Early phase: within a year of infection: spirochetes can reenter the blood 👉symptoms of secondary syphilis
📌late phase: after a year of infection: spirochetes stay in organs & tissues

Question 5

What are the features of tertiary stage of syphilis?

Answer 5

IMMUNE RESPONSE STAGE
🚩Granulomatous lesions ( GUMMA)
[ are immune cells surrounded by fibroblasts with central necrosis]
🚩organ damage: heart , brain, liver , joints , eye

Question 6

How is syphilis diagnosed?

Answer 6

1- identify spirochetes in chancres by dark field microscopy
2- non treponemal tests (nonspecific to syphilis):
* RPR
*VDRL( detect anti-cardiolipin)
3- trepenemal tests :
* TPPA
* FTA-ABS

Question 7

What is Jarisch - Herxheimer reaction?

Answer 7

📌Complicate 45% of syphilis treatment in pregnancy by penicillin
📌 spirochetes die👉 releasing lots of antigens 👉
📌 within 24 h of treatment:
1- fever / sweating
2- muscles & joints pain
3- skin rash
4- uterine contractions
resolve in few hours to few days

Question 8

What is the most congenital infection worldwide?

Answer 8

T pallidium

Question 9

According to routine antenatal screening for syphilis in UK, what is the percentage of women screened positive for syphilis annually?

Answer 9

1/700 - 1/7000
1/4 had new infections in pregnancy

Question 10

What is the occurrence rate of syphilis co-infection with HIV ?

Answer 10

40% of the patients

Question 11

How many pregnancies are affected by syphilis each year ?

Answer 11

1,5 million

Question 12

How is the fetal infection with syphilis characterized?

Answer 12

By : placental involvement + hepatic dysfunction which results in:
1- FGR
2- hepatomegaly : thrombocytopenia- anaemia- ascites
3- preterm birth
4- stillbirth - neonatal birth

Question 13

How many individuals exposed to T pallidium will become infected?

Answer 13

1/3

Question 14

Transmission of syphilis transplacentally is dependent on which factors?

Answer 14

1- stage of maternal infection
2- duration of fetal exposure
*at any time of pregnancy

Question 15

At what age of pregnancy T pallidium can cross the placenta & cause fetal infection?

Answer 15

14 weeks
The risk increase as the pregnancy progresses towards term

Question 16

What is the percentage of fetal loss caused by syphilis infection during pregnancy?

Answer 16

30 - 40 %
Caused by placental infection or compromised blood flow to the fetus

Question 17

Among survived fetus from maternal syphilis in pregnancy, how many of them will have congenital syphilis?

Answer 17

1/3 of them

Question 18

According to the stage of syphilis in the mother, what is the risk of transmission at each stage?

Answer 18

Primary 👉 100%
Early latent 👉 40 %
Late latent 👉 10 %

Question 19

What are the fetal ultrasonic features of syphilis infection?

Answer 19

General hallmarks of infection
Nonspecific
( fetal hydrops/ Intrahepatic calcification)

Question 20

What are the recommendations on testing for syphilis according to NICE?

Answer 20

1- serological:
*TPPA ( T pallidium particle agglutination )
* EIA : enzyme immunoassay ( detect IgG)
2- swab from lesions: syphilis PCR
Also to test for herpes as DDx
3- screen for other STDs

Question 21

What is the suggested screening algorithm for syphilis?

Answer 21

Detect IgG+IgM : EIA / TPPA / CLIA
👉 POSITIVE
⬇️
confirmatory test
⬇️
1- original sample for a different serological test e.g.: TPPA / TPHA
2- second sample for treponemal serology: EIA / CLIA
⬇️
1- Qualitative RPR or VDRL
( to elicit titres for monitoring )
Then repeat every 3 months
2- refer to GUM + neonatal care

Question 22

What is the standard antibiotic treatment for syphilis in primary or latent < 2 years ?

Answer 22

🍀 1st & 2nd trimester: penicillin
2.4 MU/IM single dose
🍀 3rd trimester: penicillin
2.4MU/IM weekly for 2 weeks

Question 23

What is the standard antibiotic treatment for syphilis in latent >2 years or unknown duration?

Answer 23

At any stage of pregnancy;
Bezathine penicillin 2.4 MU/IM
Weekly for 3 weeks

Question 24

What is the period of gestation that treatment of syphilis should be commenced before to lower the risk of congenital infection?

Answer 24

30 days before delivery

Question 25

For patients with syphilis who report sensitivity to penicillin G what is the alternative?

Answer 25

CEFTRIAXON 500 mg / daily / 10 days

Question 26

What is the role of macrolide in treating maternal syphilis ?

Answer 26

NO role because of:
*increasing resistance to T pallidium
* inability of macrolides to cross the placenta in adequate quantities

Question 27

For patients with syphilis who aren’t allergic to penicillin but unable to tolerate IM administration what is the alternative?

Answer 27

Amoxicillin 500 + probenecid 500
4 times a day for 14 days

Question 28

What is the occurrence rate of Jarisch - Herxheimer reaction at each stage of the disease ?

Answer 28

Primary 50 %
Secondary 90 %
Latent 25%

Question 29

What is the occurrence rate of congenital syphilis in UK?

Answer 29

0.5 / 1000 live birth

Question 30

What are the signs of early congenital syphilis ( < 2 years)?

Answer 30

2/3 of congenital syphilis are asymptomatic at birth
3- 8 w of age : skin rash , jaundice hepatospleenomegaly, rhinitis, bloody snuffles

Question 31

What are the signs of late congenital syphilis?

Answer 31

> 2 years of age : Hutchison teeth
Saddle nose , anterior bowing of mid tibia 👉 sabre shins
Mortality rate 10 %