SYPHILIS Flashcards
What is the bacteria that is responsible for syphilis?
Treponema pallidum
What type of bacteria is T. pallidum?
Coiled motile spirochaete bacterium
What are the two way in which T. pallidum can be transmitted?
Sexually transmitted
Vertical transmission - can cross the placenta easily
What other animals are known to contract T. pallidum?
No others. Humans are the only natural host.
What is the relationship between syphilis and HIV?
Ulcerative lesions of primary and secondary syphilis are a facilitator for HIV transmission.
What is the incubation period for the primary stage of syphilis?
14-21 days (range of 9 - 90 days)
What is the most common extragenital site to be inoculated with syphilis?
Mouth
What are the clinical features of primary syphilis?
Normally a solitary, painless lesion (however, can be multiple and can sometimes be painful)
Develops initially as a red macule which then becomes a papule and then eventually an ulcer.
Round clean ulcer
Indurated (hardened) base
Defined edges
Local lymph nodes are moderately enlarged, rubbery, painless and discrete
What do we call the ulcerated lesion associated with syphilis?
Chancre
How long do the primary lesions (chancres) take to heal?
3 - 10 weeks
How long after the appearance of the primary lesion does secondary syphilis develop?
4-8 weeks
In which percentage of patients will the primary chancre still be present when they develop secondary syphilis?
1/3rd of cases
What are the clinical features of secondary syphilis?
Skin lesions (80%)
Generalised lymphadenopathy (60%)
Mucous membrane erosions (30%)
Malaise, fever (15%)
Hepatitis
Glomerulonephritis and nephritic syndrome
What are the different skin lesions associated with secondary syphilis?
Macular or papular
Condylomata lata
Papulosquamous
Pustular
How big are the macular and papular lesions associated with secondary syphilis?
0.5 cm to 1 cm
Where do the lesions associated with secondary syphilis usually appear?
Trunk
Palms
Arms
Legs
Soles
Face
Genitalia
What are condylomata lata?
Areas of secondary syphilis lesions where papular lesions have enlarged and coalesced to form large fleshy masses.
Where do condylomata lata tend to form?
Warm, opposed areas of the body such as the anus or labia.
How are papulosquamous lesions formed in secondary syphilis?
When scaling of the papules occurs
What is the term used to describe papulosquamous lesions of secondary syphilis when they occur on the palms or soles?
Psoriasiform
How are pustular lesions formed in secondary syphilis?
This is when the papular lesions undergo central necrosis
What is the term used to describe the mucosal erosions that often occur in secondary syphilis?
Snail track ulcers
What percentage of untreated patients have recurrent episodes of secondary syphilis?
25% - however this is rare after the first year of infection
What do we call the phase of syphilis in an untreated individual who has no symptoms or signs of infection?
Latent syphilis
What are the two periods of latent syphilis?
Early - less than 2 years of infection
Late - more than 2 years of infection
What are the three types of late (or tertiary) syphilis?
Neurosyphilis
Cardiovascular syphilis
Gummatous syphilis
What percentage of untreated individuals with latent syphilis go on to develop neurological lesions?
10%
What percentage of untreated individuals with latent syphilis go on to develop cardiovascular lesions?
10%
What percentage of untreated individuals with latent syphilis go on to develop gummatous lesions?
15%
What are the three classifications of neurosyphilis?
Asymptomatic
Meningovascular
Parenchymatous
What is asymptomatic syphilis?
This is based purely on positive test results in serum and cerebrospinal fluid
What are the features of meningovascular tertiary neurosyphilis?
Headache
Signs of meningitis
Third, sixth and eighth cranial nerve involvement - Argyll Robertson pupils
Papilloedema
Homonymous hemianopia - rare
Hemiplegia - rare
What are the two presenting formats of parenchymatous tertiary neurosyphilis?
General paresis
Tabes dorsalis
What are the early symptoms of general paresis?
Irritability
Fatiguability
Personality changes
Headaches
Impaired memory
Tremors
What are the later symptoms of general paresis?
Lack of insight
Depression or euphoria
Confusion and disorientation
Delusions
Seizures
Transient paralysis and aphasia
What are the signs of general paresis on examination?
Expressionless facies
Tremor of lips, tongue and hands
Dysarthria
Impairment of handwriting
Hyperactive tendon reflexes
Pupillary abnormalities
Optic atrophy
Convulsions
Extensor plantar responses
How long after the original primary syphilis infection does general paresis occur?
10-20 years
What are the key features of tabes dorsalis, a type of tertiary neurosyphilis?
Increasing ataxia
Failing vision
Sphincter disturbances
Attacks of severe pain - mostly in the legs
What term is used to describe the attacks of severe pain in tabes dorsalis, a type of tertiary neurosyphilis?
Lightening pains because they occur so acutely
What are the symptoms of tabes dorsalis, a type of tertiary neurosyphilis??
Lightening pains
Ataxia
Bladder disturbance
Paraesthesia
Tabetic crises
Visual loss
Rectal incontinence
Deafness
Impotence
What are the signs of tabes dorsalis, a type of tertiary neurosyphilis?
Argyll Robertson pupils
Absent ankle reflexes
Absent knee reflexes
Absent biceps and triceps reflexes
Romberg’s sign
Impaired vibration sense
Impaired proprioception
Impaired sense of touch and pain
Optic atrophy
Ocular palsis
Charcot’s joints
What is the majority of the signs of tabes dorsalis due to in terms of pathophysiology?
Degeneration of the posterior column
What is most commonly affected in cardiovascular tertiary syphilis?
The large vessels, particularly the aorta.
How is the aorta affected in tertiary syphilis?
Aortitis - with or without coronary ostial stenosis
Aneurysm of ascending part
Aortic incompetence
What is gummatous syphilis?
These are granulomatous lesions or necrotic nodules that develop 3-12 years after primary infection. Gummata may occur pretty much anywhere - skin, mucous membranes, bones or viscera.
What are the features of skin gummata associated with tertiary syphilis?
Found in small groups
Painless lesions
Indolent
Firm
Coppery red
0.5 - 1 cm diameter
What investigations can be used to confirm a diagnosis of syphilis?
PCR and NAATs
Dark ground microscopy
Serology
Examination of CSF
Radiology
What are the direct tests used to diagnose syphilis infection?
PRC of ulcer swab
Dark ground microscopy - rarely used nowadays
How many samples need to be taken for dark ground microscopy diagnosis of syphilis?
Normally 3 separate specimens from the lesions, often on 3 separate days
What are the non-specific serological tests used in the diagnosis of syphilis?
Rapid plasma reagin (RPR)
Venereal disease reference laboratory (VDRL)
What are the specific serological tests used in the diagnosis of syphilis?
T. pallidum enzyme immunoassay (EIA)
T. pallidum particle agglutination (TPPA)
Chemiluminescent microparticle immunoassay (CMIA)
Absorbed fluorescent treponemal antibody (FTA)
T. pallidum haemagglutination assay (TPHA)
What are specific serological tests for syphilis useful for?
Confirming diagnosis particularly at first presentation, however, these tests usually remain positive throughout a patient’s life even after successful treatment.
What are non-specific tests for syphilis useful for?
Monitoring response to treatment and the diagnosis of reinfection of syphilis. However, they have a high false positive rate.
What is the window period for the specific EIA syphilis test?
14-21 days
What is the window period for the specific TPPA syphilis test?
21-28 days
What is the window period for the non-specific RPR syphilis test?
28 days (range of 3-5 weeks)
Other than syphilis, what can cause a rise in RPR?
Pregnancy
Acute and chronic infections (eg herpes, measles and mumps)
Autoimmune conditions such as SLE and rheumatoid arthritis
What is the diagnostic criteria in terms of RPR for re-infection of syphilis?
4 fold increase - remember RPR gives you a titre.
What would the following serology results indicate with regard to syphilis infection?
PRC - positive
EIA - negative
TPPA - negative
RPR - negative
Primary syphilis
What would the following serology results indicate with regard to syphilis infection?
EIA - positive
TPPA - positive
RPR - negative
Previously treated syphilis
OR
New syphilis still within window period for RPR
OR
Untreated late or latent syphilis
What would the following serology results indicate with regard to syphilis infection?
EIA - positive
TPPA - negative
RPR - negative
Early primary syphilis
OR
False positive
What would the following serology results indicate with regard to syphilis infection?
EIA - positive
TPPA - negative
RPR - positive
Primary syphilis if ulcer present
What would the following serology results indicate with regard to syphilis infection?
EIA - negative
TPPA - negative
RPR - positive
False positive
What will CSF tests show in someone with neurosyphilis?
WCC - More than 5 x 10^6/L
Protein - more than 40g/L
What syphilis diagnostic tests can be done on CSF?
All the specific and non-specific serological tests. Positive RPR will usually indicate neurosyphilis, as long as sample is not contaminated with macroscopic blood.
Which syphilis patients should be offered a chest x-ray?
All those who may have had infection for more than 20 years.
Chest x-ray needs to show the arch of the aorta to screen for aortic dilatation.
What is the treatment of primary, secondary or early latent syphilis?
Benzathine penicillin 2.4 mega units IM as single dose
OR
Aqueous procaine penicillin 600 000 units IM OD for 10 days
What is the treatment of primary, secondary or early latent syphilis in someone who is allergic to penicillin?
Doxycycline 100 mg BD for 14 days
What is the treatment of late latent, cardiovascular or gummatous syphilis?
Benzathine penicillin 2.4 mega units IM weekly over 2 weeks (3 injections)
OR
Aqueous procaine penicillin 600 000 units IM OD for 17 days
What is the treatment of late latent, cardiovascular or gummatous syphilis who is allergic to penicillin?
Doxycycline 100 mg BD for 28 days
What is the treatment of neurosyphilis?
Aqueous procaine penicillin 1.8-2.4 mega units IM OD for 17 days
AND
Probenecid 500mg QDS for 17 days
What is the treatment of neurosyphilis who is allergic to penicillin?
Doxycycline 100 mg BD for 28 days
What is the name of the reaction to syphilis treatment?
Jarisch-Herxheimer reaction
What are the features of the Jarisch-Herxheimer reaction to syphilis treatment?
Fever
Flu-like symptoms
Occasionally chancre or skin lesions enlarge or become more widespread
How long after initiation of treatment for syphilis does the Jarisch-Herxheimer reaction tend to occur?
3-12 hours after the injection of penicillin
How do we treat the Jarisch-Herxheimer reaction to syphilis treatment?
Reassurance
Antipyretics
How far back must you go in terms of contact tracing for someone diagnosed with infectious syphilis?
Early infectious syphilis: 3-6 months
Late syphilis patient is no longer infectious so only practical to test current regular partners
What are the differences seen in someone with syphilis who is HIV positive versus someone who is HIV negative?
Primary syphilis: larger, painful, multiple ulcers
Secondary syphilis: genital ulcers (slow healing of primary ulcers), higher titres of RPR
Possibly more rapid progression to neurosyphilis
