STI - Sexually Transmitted Infections PDF

Prof. Dr. Haider Al-Sabak Dermatologist & Aesthetic Physician, MD Head of Dermatology Department  Sexually Transmitted Infections STI  Syphilis the causative organism, Treponema pallidum, may be congenital (less commonly, transplacentally from moth...

Prof. Dr. Haider Al-Sabak Dermatologist & Aesthetic Physician, MD Head of Dermatology Department  Sexually Transmitted Infections STI  Syphilis the causative organism, Treponema pallidum, may be congenital (less commonly, transplacentally from mother to unborn child), or acquired through transfusion with contaminated blood, or by accidental inoculation. The most important route, however, is through sexual Loading… contact with an infected partner. In many parts of the world, syphilis continues to be a major public health problem. Despite therapeutic “magic bullets,” the disease remains a formidable opponent.  T. pallidum, a motile, corkscrew-shaped, prokaryotic bacterium with a flexible, helically coiled cell wall. The organism is microscopically indistinguishable from treponemes that cause pinta, yaws. Its narrow width renders the organism undetectable by light microscopy without silver staining. Under dark-field microscopic examination, the treponemes resemble strings of beads with a characteristic rotatory motion and a flexion and backword. This motion is said to be characteristic of virulent treponemes and to facilitate penetration through tissue. Loading… Coarse of the disease Acquired syphilis: Primary stage: After an incubation period (9–90 days), a primary chancre develops at the site of inoculation. Often this is genital, but oral and anal chancres are not uncommon. A typical chancre is an ulcerated, although not painful, button-like lesion of up to 1 cm in diameter accompanied by local lymphadenopathy. Untreated it lasts about 6 weeks and then clears leaving an inconspicuous scar.  The secondary stage may be reached while the chancre is still subsiding. Systemic symptoms and a generalized LAP. skin eruptions that at first are macular, and later papular, distributed symmetrically and are of a coppery ham color. Sometimes they resemble pityriasis rosea. Classically, there are obvious lesions on the palms and soles. Annular lesions are also not uncommon. lata are moist papules in the genital and anal areas. a ‘moth-eaten’ alopecia. mucous patches in the mouth.  The skin lesions of late syphilis may be nodules that spread peripherally and clear centrally, leaving a serpiginous outline. Gummas are granulomatous areas; in the skin they quickly break down to leave punched-out ulcers that heal poorly, leaving papery white scars. Loading…  STIGMATA OF CONGENITAL SYPHILIS Oral Hutchinson teeth, Gummas in nose or palate, Mulberry molars, High-arched palate Saddle nose Orthopedic Frontal bossing, Periostitis, Short maxilla, Dactylitis, Protuberant mandible, Clutton's joint, Saber shins, Scaphoid scapula, Thickened medial clavicle Neurologic Eighth nerve deafness, Neurosyphilis Mucocutaneous Gummas Gastrointestinal Hepatomegaly Splenomegaly  Differential diagnosis Chancre: chancroid (multiple and painful), herpessimplex, anal fissure, cervical erosions. Secondary syphilis: Eruption-measles, rubella, drug eruptions, pityriasisrosea, lichen planus, psoriasis; Condyloma - genital warts, haemorrhoids; oral lesion - aphthous ulcers, candidiasis. Late syphilis: bromide and iodide reactions, other granulomas, erythema induratum  Investigations: The diagnosis of syphilis in its infectious (primary and secondary) stages can be confirmed using dark field microscopy to show up spirochaetes in smears from chancres, oral lesions, or moist areas in a secondary eruption. Serological tests for syphilis become positive only some 5–6 weeks after infection (usually a week or two after the appearance of the chancre). The non specific or non treponemal test: Venereal Disease Research Laboratory (VDRL) used for screening and assessment of response to treatment  The specific or treponemal test: the rapid plasma reagin (RPR) test and the fluorescent treponemal antibody/absorption (FTA/ABS) test, these types of tests are specific and remain positive life long so not useful for treatment response.  Treatment This should follow the current recommendations of the World Health Organization (WHO). Penicillin is still the treatment of choice (e.g. for early syphilis benzathine penicillin 1.2 million units given intramuscularly into each buttock at a single session, or procaine penicillin 600 000 units intramuscularly daily for 12 days), with long-term high-dose oral erythromycin and tetracycline being effective alternatives for those with penicillin allergy. The use of long-acting penicillin injections overcomes the ever-present danger of poor compliance with oral treatment. Every effort must be made to trace and treat infected contacts.