SYPHILIS IS : a sexual transmitted disease caused by spirochetal bacterium Treponema pallidum a motile anaerobic.
• Transmission : is almost always through sexual contact or congenitally through the placenta to a foetus or at birth from an infected mother.
• Different manifestations occur depending on the stage of the disease
Primary Syphilis
• It’s the first stage after infection.
• Painless & localized ulcer with rolled edge (chancres)
• Single or multiple
• Appear 2-3 weeks after contact
• Most common site are cervix, vagina, vulva, anus and mouth
• Regional lymphatic node become enlarged
Incubation period 9-90 days, usually <21 days Develops at site of contact/inoculation
Classically : single, painless, clean-based, indurated ulcer (increasing fibrous material), with firm, raised borders. Atypical presentations may occur.
Mostly anogenital (related to anus and genitals), but may occur at any site (tongue, pharynx, lips, finger, nipples, etc)
Non-tender regional adenopathy Very infectious
May be darkfield positive but serologically negative
Untreated, heals in several weeks, leaving a faint scar.
Secondary Syphilis
• The skin rash : Diffuse; often with a superficial scale (papulosquamous); may leave residual pigmentation or depigmentation
• Condylomata Lata : formed by coalescene of large, pale, flat-topped papules; occur in warm, moist areas such as the perineum (the area between the anus & scrotum); Highly infectious.
• Mucosal lesions : 30% of secondary syphilis patients develop mucous patch (slightly raised, oval area covered by a greyish white membrane, with a pink base that does not bleed). Highly infectious.
• Systemic : 1-6 months after contact; fever, malaise, general adenopathy and non-itchy maculopapular skin rash “money spot”; involve the palms of the hands and the soles of the feet; mucous patches and linear (snail track) ulcers are seen on the mucosal surfaces.
Seen 6 weeks to 6 months after primary chancre
• Usually diffuse non-pruritic, indurated rash, including palms & soles.
• May also cause : fever, malaise, headache, sore throat, myalgia (pain in a muscle), arthralgia (related to joint pain), generalized lymphadenopathy; hepatitis (10%)
• Renal : an immune complex type of nephropathy with transient nephrotic syndrome (kidney disease); iritis (an inflammation of middle layer of eye) or an anterior uveitis
• Bone : periostitis (inflammation of the membrane enveloping a bone)
• CSF pleocytosis (large number of lymphocytes) in 10-30% (but, symptomatic meningitis is seen in <1%)
Differential diagnosis of Secondary Syphilis
• The rash may be confused with pityriasis rosea (a skin rash begins as a large spot on the chest); drug eruptions; acute febrile exanthems (skin rash) ; psoriasis (a condition in which skin cells build up & form scales and itchy, dry patches) ; lichen planus (an inflammatory condition of the skin and mucous membranes); scabies (a contagious, intensely itchy skin condition caused by a tiny burrowing mite)
• The mucous patch may be confused with oral thrush ( fungal infection of mouth).
• Malaise, sore throat; generalized adenopathy, hepatitis & rash may be confused with infectious mononucleosis (extreme fatigue). accuracy is 99%.
Latent Syphilis
• Positive syphilis serology without clinical signs of syphilis (& has normal CSF).
• It begins with the end of secondary syphilis and may last for a lifetime.
• Pt may or may not have a primary or secondary syphilis
• Diseases known to cause occasional false-positive nontreponemal test reactions for syphilis, such as systemic lupus erythematosus (autoimmune disease in which body’s immune system mistakenly attacks healthy tissue in many parts of the body) (SLE), and congenital syphilis must be excluded before the diagnosis of latent syphilis can be made.
• It is divided into early and late latency.
(1) Early latent :
• The first year after the resolution of primary or secondary lesions, or
• A reactive serologic test for syphilis in an asymptomatic individual who has had a negative serologic test within the preceding year.
• infectious
(2)Late latent :
Usually not infectious, except for the pregnant woman, who transmit infection to her foetus
Latent Syphilis / Tertiary Syphilis
• It is the destructive stage of the disease.
• Lesions develop in skin, bone, & visceral organs (deep down of organ) (any organ).
• The main types are : late benign (gummatous/ non-cancerous tissues formed during late stage of syphilis); cardiovascular; neurosyphilis
• It can be crippling and life threatening.
• Blindness, deafness, deformity, lack of coordination, paralysis, dementia (memory loss) may occur.
• It is usually very slowly progressive, barring certain neurologic syndromes which may develop suddenly due to endarteritis (an inflammation of the inner lining of an artery) and thrombosis (local coagulation or clotting of the blood in a part of the circulatory system) in the CNS.
• Late syphilis is non-infectious
• Positive syphilis serology without clinical signs of syphilis (has normal CSF)
• It begins with the end of secondary syphilis and may last for a lifetime
• Pt may or may not have a primary or secondary syphilis.
• Disease known to cause occasional false-positive nontreponemal test reactions for syphilis, such as systemic lupus erythematosus (SLE), and congenital syphilis must be excluded before the diagnosis of latent syphilis can be mode.
• It is again divided into early and late latency
• Latent syphilis :
Absent of symptoms or physical finding.
• I/3 proceed to tertiary
• Tertiary syphilis :
• Occur :1-10 years after infection
• Gummas : ulcerative nodule in the skin, bone and nervous system as a result of heper-sensitivity reactions
• Systemic manifestation: CVS, CNS and bone
Conenital Syphilis :
• Mode of transmission :
• Trans placental passage from infected mother
• At birth
• Congenital infection is associated with several adverse outcome including :
• Low birth weight
• Premature birth
• Congenital abnormalities
• Miscarriages or death of baby
Early
• Skin lesions, maculopapular tissue
• Lymphadenopathy
• Hepatosplenomegaly
• Failure to thrive
• Jaundice, anaemia
• osteochondritis
Late :
gummites ulcers
bony prominence of forehead saddle nose
short maxilla (jaw bone)
keratitis (inflammation of the cornea of the eye) nerve deafness and dental deformities
Diagnostic Evaluation of Syphilis
• Direct detection of Treponema pallidum
• Nontreponemal Serological Tests
• Treponemal Serological Tests
TESTS FOR DIRECT DETECTION OF T. pallidum
• Animal Inoculation
• Dark Field microscopy
• Direct fluorescent antibody testNONTROPONEMAL SEROLOGICAL TESTS
Serological nontreponemal tests
• VDRL (Venereal disease research laboratory test)
• USR (Unheated of serum regain Test)
• Macroscopic nontreponemal tests
• RPR (Rapid plasma regain test)
• TRUST ( Toluidine red unheated serum test)
• Direct tests for T. pallidum in tissue sections
• Nucleic acid amplification methods
TREPONEMAL SEROLOGICAL TESTS
• FTA-ABS (Fluorescent treponemal antibody absorption test)
• FTA-ABS double staining (Fluorescent treponemal antibody absorption double staining test)
• TP-PA test (Treponema pallidum particle agglutination test)
• Western blots
• ElAs (Enzyme immunoassays) / Rapid tests
Animal Inoculation
• Oldest method for detecting infection
• Most sensitive method for detecting infectious treponemes and is used as the gold standard for measuring the sensitivity of methods such as the PCR
• Rabbit is most commonly used
• Any source of specimen can be used as long as the material is less than 1 h old or was frozen immediately after collection
• Inoculation of sample : intra-testicular or intradermal
• Incubation period : inversely proportional to the size of inoculum
• Sensitivity of RIT approaches 100% if the number of organisms exceeds 23 and patient has not received antibiotic treatment.
Dark Field Microscopy
• One simplest and most reliable for the direct detection of T. pallidum
• exudates and fluids from lesions are examined as a wet mount
• Examination should be done immediately
• Most productive during 1*, 2*, early relapsing, and early congenital syphilis when lesions contains large numbers of treponemes (chancres, condylomata latum, or mucous patches)