Treponema pallidum
Contagious, sexually transmitted disease Spirochete Treponema pallidum Enters through skin or mucous membrane where primary infections are seenSpiral spirochete that is mobile Length 5 to 20 microns Can be seen on fresh primary or secondary lesions by darkfield microscopy or fluorescent antibody techniques
Motility has three movements Projection and rotation in the direction of the long axis Bending or twisting from side to side Pathogenic in humans, and rabbits
Major health problem throughout world Lowest level ever recorded Concentrated in 28 countries in U.S. Mainly gay men and crack cocaine users
Enhances risk of transmission of HIV HIV testing recommended in all patients with syphilis
RPR : rapid plasma reagin VDRL : Venereal Disease Research LaboratoryPositive within 5 to 6 weeks after infection Strong positive in secondary phase May become negative with treatment or over decades
To improve sensitivity and specificity tests using a specific treponemal antigen devised MHA-TP: microhemagglutination assay for T. pallidum FTA-ABS: fluorescent treponemal antibody absorption test
Treponemal tests become positive early, useful in confirming primary syphilis Remain positive for life, useful in diagnosing late disease Treatment results in loss of positivity in 13-24% of patients
Acute BFP Vaccinations Infections pregnancy
Chronic BFP Connective tissue disease (SLE) Liver disease Blood transfusions IVDAChancre Inguinal adenopathy 1-2 weeks after chancre Generally occur singly, may be multiple Diameter mm to cm
Women genital chancre less often observed due to location within the vagina and cervix Edema of labia may occur
Untreated, the chancre heals spontaneously in 1 to 4 months Extragenital chancre: may be larger, frequently on lips, rarely tongue, tonsil, breast, finger, anus.
Ulcer covered by neutrophils and fibrin Dense infiltrate of lymphocytes and and plasma cells Spirochetes in untreated primary syphilis with stained with silver stains
Skin manifestations in 80% called syphilids Symmetric, generalized, superficial, macular transient; later papular, pustular Early on face, shoulders, palms and soles, anal or genital areas
Exanthematic erythema 6-8 weeks after chancre, extends rapidly, may last hours to months Round slightly scaling colored macules Pain, burning absent, pruritus may be present Generalized adenopathy
Arise later than macular, round, 2-5mm or more in diameter, slightly raised, smooth or thick scaleFace and flexures of arms and legs, trunkPalmar and plantar yellowish-red spotsOllendorf’s sign; papule tender to touch of a blunt probe
Present in 1/3 of secondary syphilisMost common is “syphilitic sore throat”Diffuse pharyngitis, hoarsenessTongue; patches of desquamation of papillae Ulcerations of tongue and lips in late stages
Tertiary syphilis usually occur 3-5 years after infection 16% of untreated pts will develop lesions of skin, mucous membrane, bone or joints Skin lesions are localized, destructive, heal with scarring
Syphilis >1year; 2.4M PCN G weekly for 3 weeks Pcn-allergic; Tetra 500mg QID for 30 days Infant 100,000 to 150,000 units/kg/day Procaine PCN for first seven days of life