Sexually transmitted disease (STD)

Sexually transmitted disease (STD)

·         It is a group of communicable diseases in which sexual contact is the most important mode of transmission.

·         Sexual intercourse

·         Oral-genital contact or in non-sexual ways.

·         IV drug

·         Congenitally transmitted


1.      Viral

o   ADIS

o   Genital herpes simplex

o   Genital warts

2.      Bacterial

o   Syphilis

o   Gonorrhea

o   Non-gonorrheal urethritis

o   Chancroid

o   Non-specific vaginitis

o   Granuloma inguinale

3.      Parasitic

o   Trichomonas vaginitis and urethritis

o   Scabies

o   Pediculosis pubis

4.      Fungal

o   Vaginal thrush

o   Vulvovaginitis

o   Balanitis


·         It is a chronic venereal infection caused by the spirochete Treponema pallidum.

·         Discovered by Schaudinn and Hoffmann(1905)

·         Affects both man & women in the age group of 20-40 years.


·         Contact with an open lesion

o   Contaminated articles

o   Sexual contact with infectious lesions

o   Kissing

·         Congenital infection

o   Transplacental from the 4th month till delivery (not before because Treponema cannot pass the placental barrier).

·         Inoculation infection

o   contaminated blood & body fluids


·         Early-stage

o   Primary (Painless sore (chancre) at inoculation site)

o   Secondary (Rash, Fever, Lymphadenopathy, Malaise)

o   Latent (CNS invasion, organ damage)

·         Late-stage

·         Tertiary

o   Benign territory

o   Cardiovascular

o   Neuro-syphilis

Acquired syphilis

Primary syphilis

·         Incubation period 14-28 days.

·         A dull red macule → papular → indurated ulcer – Hard Chancre.

·         Inguinal lymph nodes enlarged.

·         Chancre and lymph nodes: painless.

·         Without treatment, resolves within 2-6 weeks to leave a thin atrophic scar.

·         Extra genital chancres – fingers, tongue, tonsil, nipple, anus.

·         Diagnosed by Darkfield microscopy or direct Fluorescent Ab tests of exudates.

Secondary syphilis

·         It appears 6-8 weeks after the development of chancre when Treponema disseminates.

·         It causes Mucocutaneous lesions & generalized lymphadenopathy.

·         Fever, malaise, headache common.

·         Rashes on the trunk, on palms & soles.

·         Condyloma lata in warm moist areas – vulva, perianal areas.

·         Mucosal patches – genitalia, mouth, pharynx, and larynx.

·         Less common: hepatitis, renal, eye & GI abnormalities.

·         Diagnosed by serological tests.

Latent syphilis

·         Asymptomatic but the presence of positive syphilis serology.

·         1. Early Latency: within 1 year of infection, maybe transmitted sexually.

·         2. Late Latency: patient no longer sexually infectious.

Tertiary syphilis

Benign tertiary syphilis

·         Affected part: Skin, mucous membrane, bone, muscle, and viscera.

·         Gumma: granulomatous lesion.

·         Slowly heal the formation of tissue paper scars.

Cardiovascular syphilis

·         Aortitis may involve aortic valve / coronary Ostia.

·         Clinical features – aortic incompetence, angina, and aortic aneurysm.

·         The proximal aorta is mainly involved.

·         Surgical intervention required.

·         The proximal aorta is mainly involved.

·         Surgical intervention required.


·         Asymptomatic infection with CSF abnormalities.

·         Symptomatic forms: Meningovascular disease, Tabes dorsalis, and General paresis.

Congenital syphilis

·         Greater chance during early stages of the disease.

·        Stigmata does not develop until 4th month of pregnancy.



1. Stillbirth

·         Hepatomegaly, bone abnormalities, pancreatic fibrosis & pneumonitis.

2. Infantile syphilis

·         Rhinitis (snuffles), Mucocutaneous lesions.

·         Visceral & skeletal changes, ascites, hydrops.

3. Late / Tardive syphilis

·         Hutchinson triad – notched central incisors, interstitial keratitis with blindness & deafness from 8th nerve injury.

·         Saber shin deformity

·         Mulberry molars

·         Saddle nose deformity

·         Clutton joints

Serological tests

1. Non Treponema (nonspecific) tests:

        i.            Venereal Disease Research Laboratory ( VDRL ) test

      ii.            Rapid Plasma Reagin ( RPR ) test

2. Treponema (specific) tests:

        i.            Treponemal antigen-based Enzyme Immunoassay (EIA) for IgG & IgM.

      ii.            T.pallidum Hemagglutination Assay ( TPHA )

    iii.            T.pallidum Particle Agglutination Assay ( TPPA )

    iv.            Fluorescent Treponemal Antibody-Absorbed ( FTA-ABS ) test

·         CSF examination



·         Benzathine Penicillin 2.4 MU single dose before or 12 hrs within contact affords protection.

·         Procaine Penicillin 2.4 MU i.m. into each buttock (total 4.8 MU), preceded by 1g of Probenecid helps to prevent both Syphilis and Gonorrhea.





Early (Primary, secondary and latent < 1 yr)

Benzanthine Penicillin 2.4 MU i.m., 1-3 weekly injection.




Procaine Penicillin 1.2 MU i.m × 10 days

Doxycycline 100mg BD oral 15 days




Ceftriaxone 1g i.m/i.v. 7 days




Erythromycin 500mg QID oral 15 days




Desensitization and treatment with Penicillin


Benzanthine Penicillin 2.4 MU i.m., weekly 4 weeks 




Procaine Penicillin 1.2 MU i.m × 20 days





Ceftriaxone 1g i.m/i/v. 15 days




Erythromycin 500mg QID oral 30 days




Desensitization and treatment with Penicillin







Aqueous crystalline   Penicillin G (18-24 MU/d) i.v., given as 6 divided doses or continuous infusion) for 10-14 days




Aqueous procaine penicillin G (2-4 MU/day i.m) + oral Probenecid (500 mg QID), both for 10-14 days.

De-sanitization and treatment with penicillin.


·         Azithromycin 2g single dose is an alternative.

·         Successful treatment → resolution of clinical signs, declining titers of non-treponemal tests (four-fold decline).

Syphilis in Pregnancy

·         T.pallidum enters fetal circulation after the 20th week, fetal infection unlikely before that.

·         Perinatal effects max with primary & secondary syphilis.

·         Penicillin – drug of choice.

·         For 1° & 2° or latent syphilis of less than 1 yr duration,

o   Benzathine PenicillinG 2.4 MU i.m, as a single dose


o   Crystalline Benzyl Penicillin for 10 days

·         When duration is > 1 yr,

o   Benzathine Penicillin 2.4 MU i.m, weekly for 3 doses are given.

·         Breastfeeding is not contraindicated.

·         Every neonate with congenital syphilis should be treated:

o   Benzyl Penicillin for 10 days

o   For Interstitial keratitis, local/systemic Glucocorticoids.

o   Alternative – Erythromycin stearate

o   500mg, once in 6 hrs x 2 weeks



·         It is a bacterial infection caused by Neisseria gonorrhoeae that causes urogenital, anorectal, conjunctival, and pharyngeal infections.

·         Urogenital tract infections are most common.

·         Transmission: direct sexual contact.

·         Incubation period: 3-4 days.


1. Adherence

·         Initial event, N. gonorrhoeae adhere to mucosal cells, mediated by pili, Opa, and other surface proteins.

2. Invasion

·         Organism is then pinocytosed by epithelial cells, which transport gonococci from mucosal surface to subepithelial spaces.

·         Simultaneous with attachment of gonococci to nonciliated epithelial cells, gonococcal LOS (endotoxin) impairs ciliary motility and contributes to destruction of surrounding ciliary cells.

·         This process may promote further attachment of additional organisms.

3. Tissue damage

·         Progressive mucosal cell damage and submucosal invasion are accompanied by a vigorous neutrophil response, submucosal microabscess formation, and exudation of purulent material into lumen of the infected organ.

4. Dissemination

·         ability to resist the killing activity of antibodies and complement in normal human serum is closely related to the ability of gonococci to cause bacteremic illness with or without septic arthritis.


Asymptomatic infection

·         Urethra

·         Endocervix

·         Rectum

·         Pharynx

Symptomatic infection

·         Urethritis

·         Cervicitis

·         Proctitis

·         Pharyngitis

·         Batholinitis

·         Conjunctivitis  

Local complication

·         Salpingitis

·         Epididymitis

·         Bartholin abscess

·         Lymphangitis  

·         Penile edema

·         Periurethral abscess

·         Prostatitis


·         Acute anterior urethritis is most common in men.

·         Incubation period: 1-14 days or more.

·         Symptoms develops: 2-5 days.

·         Predominant symptoms are urethral discharge or dysuria.

·         Appear mucoid or mucopurulent.

·         Variable degrees of edema and erythema of the urethral meatus commonly accompany gonococcal urethritis.


·         Primary site: endocervical canal.

·         Infection of Bartholin’s gland is more common

·         Incubation period: usually 10 days.

·         Lower genital tract infections is most common symptoms.

·         Increased vaginal discharge, dysuria, intermenstrual uterine bleeding, and menorrhagia.

·         Purulent exudate occasionally may be expressed from urethra or Bartholin’s gland duct.


·         Rectal mucosa is infected in 35–50% of women with gonococcal cervicitis. Only rectum is involved in 5% women.

·         40% in homosexual men.

·         Symptoms range from minimal anal pruritus, painless mucopurulent discharge or scant rectal bleeding, to symptoms of overt proctitis, including severe rectal pain, tenesmus, and constipation.

·         Occasionally shows erythema and abnormal discharge.


·         Acute pharyngitis or tonsillitis and occasionally is associated with fever or cervical lymphadenopathy.

·         More than 90% are asymptomatic.


·         Gonococcal conjunctivitis is rare.

·         Primary cutaneous infection i.e. localized ulcer of genitals, perineum, proximal lower extremities, or finger is rare.



·         Epididymitis:-present in up to 20%. Most common causes of acute epididymitis in patients under age 35 are Chlamydia trachomatis, Neisseria gonorrhoeae.

·         Penile Lymphangitis: penile edema.

·         Post-inflammatory urethral strictures.

·         Periurethral abscesses.


·         Pelvic inflammatory disease most common of all complications of gonorrhea.

·         10–20% of those with acute gonococcal infection.

·         Bartholin’s gland abscess


·         DISSEMINATED GONOCOCCAL INFECTION: – More common in female.

·         DGI, usually manifested by acute arthritis-dermatitis syndrome, is most common systemic complication of acute gonorrhea.


·         Gram’s stain

·         Culture medium.

·         Serological test


Uncomplicated Gonococcal infection of cervix, urethra and rectum

Single dose of Tab. Cefixime 400mg, Inj. Ceftriaxone 125 mg IM, tab. Ciprofloxacin 500mg, tab. Ofloxacin 400mg, or tab. Levofloxacin 250mg


If chlamydial infection is not ruled out- tab. Azithromycin 1 g single dose or tab. Doxycycline 100mg BID x 7days.

Uncomplicated Gonococcal infection of pharynx

·         Single dose of Inj. Ceftriaxone 125 mg IM, or tab. Ciprofloxacin 500mg


·         If chlamydial infection is not ruled out- tab. Azithromycin 1 g single dose or tab. Doxycycline 100mg BID x 7days.

Disseminated gonococcal infection (DGI)

·         Inj. Ceftriaxone 1 g IM or IV daily

Alternative regimens

·         Inj. Cefotaxime 1 g IV 8 hourly, Inj. Ceftizoxime 1 g IV 8 hourly, Inj. Ciprofloxacin 400 mg IV BD, Inj. Ofloxacin 400mg IV BD, Inj. Levofloxacin 250mg IV daily OR Inj. Spectinomycin 2 g IM BD

·         All of the preceding regimens should be continued for 24-48 hrs after improvement begins, at which time therapy may be switched to one of the following regimens to complete at least 1 week of therapy

·         Tab. Cefixime 400mg BD, tab. Ciprofloxacin 500mg BD, ofloxacin 400mg BD OR tab. Levofloxacin 500mg OD.

Gonococcal conjunctivitis

·         Inj. Ceftriaxone 1 g IM single dose.

·         Gonococcal meningitis: – Inj. Ceftriaxone 1-2 g IV every 12 hrs x 10-14 days.

·         Gonococcal endocarditis:- Inj. Ceftriaxone 1-2 g IV every 12 hrs for at least 4 weeks

·         Ophthalmia neonatorum: Inj. Ceftriaxone 25-50 mg/kg IV/IM single dose( not more than 125 mg).

Non Gonococcal Urethritis


·         Characterized by urethral discharge, dysuria, or itching at the end of the urethra, in the response of the urethra to inflammation, of any etiology.

Non gonococcal urethritis (NGU)

·         Urethritis caused by any aetiology other than N. gonorrhoeae or wherein N. gonorrhea is not detected.

Post-gonococcal urethritis (PGU)

·         It is NGU occurring after curative therapy for gonorrhea, is called postgonococcal urethritis.




·         Neisseria gonorrhoeae

·         Bacterial

·         Viral

·         Fungal

·         Protozoal

·         Mechanical or chemical

Non-Gonococcal Urethritis (Causative Agent)





Mechanical or chemical irritation

·         Chlamydia trachomatis

·         Ureaplasma urealyticus

·         Mycoplasma hominis

·         Gardnerella vaginalis

·         Acinetobacter wolfii

·         Acinetobacter caloaceticus

·         Herpes virus

·         CMV

·         Candida albicans

Trachomonas vaginalis



·         Chlamydia trachomatis (15-40%)

·         Mycoplasma genitalium (15-25%)

·         OTHERS (20-50%)

o   T Vaginalis

o   U Urealiticum

o   HSV (In absence of skin lesions)

o   Adeno Virus

o   Haemophilus

o   Miscellaneous

§  In association with urinary tract infection,

§  Bacterial prostatitis,

§  Urethral stricture,

§  Phimosis,

§  Secondary to instrumentation of the urethra,

§  Congenital abnormalities,

§  Chemical irritation,

§  Tumors.

Pre-disposing risk factors

·         Sexual contact in which exchange of body fluid may occur.

·         May report multiple sexual partners.

·         Non-STI: secondary to catheterization or other instrumentation of the urethra, in association with other factors that contribute to urinary tract infection.

·         Incubation period- 7-21 days.

Clinical features

·         Variable dysuria

·         Urethral itching

·         Discharge- typically mucoid to watery (white)

·         10% NGU are asymptomatic


·         Gram staining of discharge or sediment of First Voided Urine: (Symptomatic/asymptomatic).

·         Absence of Gonorrheal Diplococci.

·         Presence of leukocytosis

·         More than 5 PMNs per high power field.(in Minimum of 5 fields observed.


·         Epididymitis

·         Urethral strictures

·         Transmission


·         Doxycycline 100mg B.D

·         Azithromycin 1g once

·         Ofloxacin 400mg B.D × 7days




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