Download MBBS Dermatology PPT 25 Sexually Ttansmitted Infections Sti II Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Dermatology PPT 25 Sexually Ttansmitted Infections Sti II Lecture Notes


Sexually Ttansmitted Infections ?

I ; NACO Guidelines for STIs

Chancroid / Soft chancre / Ducrey's

disease

? Acute, autoinoculable STI
? Etiologic agent: Gram negative facultative,

anaerobic bacillus Haemophilus ducreyi

? `School of fish' or `rail road track' appearance

in Gram stained smears

? Age group: 20-30 years
? Males affected more commonly
Clinical features

? Incubation period- 3-10 days
? Sites: Frenulum, prepuce, coronal sulcus in

male and; vulva, vestibule in females

? Painful genital ulcers, non-indurated (soft

chancre/soft sore), bleed on touch

? Edema of prepuce
? Tender inguinal lymphadenopathy (unilateral

in majority), sometimes suppurative

Investigations

? Microscopy:
? Gram stain ? low sensitivity; may show classic

appearance

? Culture - < 80% sensitivity

? Molecular techniques- PCR
Treatment

? Recommended regimen
Azithromycin 1 g orally single dose
or
Ceftriaxone 250 mg IM in a single dose
or
Ciprofloxacin 500 mg twice daily x 3 days

or

Erythromycin base 500 mg orally three times a day x

7 days

Lymphogranuloma Venereum

(LGV)

? Also k/a tropical bubo or lymphogranuloma

inguinale or Durand-Nicolas-Favre disease

? Caused by Chlamydia trachomatis serovars L1,

L2 & L3

? Incubation period ? 3-12 days
? Males in age group ? 20-30 years
Pathogenesis

? Enters through skin abrasions or mucous

membranes via the lymphatics multiply

within mononuclear phagocytes in regional

nodes

? Thrombolymphangitis & perilymphangitis

occur

? Necrosis & the formation of stellate abscesses
? Fistulae & sinus tract formation; may be f/b

healing with fibrosis

Clinical features

Primary stage (Genital)
? Superficial ulceration, which looks like herpes,

is temporary and heals without scarring

? It may not be noticed (GUD with no ulcer)
Clinical features

Inguinal syndrome (Secondary stage)
? Most common manifestation: bubo - u/l or b/l
? Occurs - 2-6 weeks later
? More common in males
? Painful inguinal lymphadenitis with associated

constitutional symptoms

? Enlargement of the femoral & inguinal lymph

nodes separated by the inguinal ligament ?

"groove sign of Greenblatt"

? Suppuration and sinus formation

Clinical features

Anorectal syndrome (Tertiary stage)
? May occur many years later
? Results from fibrosis & lymphatic obstruction
? Penile and scrotal elephantiasis
? Females-elephantiasis of the vulva and clitoris
? Fistulae, chronic ulceration, scarring &

deformity
Clinical features

? Late complications - include rectal strictures,

chronic rectovaginal & urethral fistulae

? May predispose to malignant change

Investigations

? Diagnostic method of choice is by nucleic acid

amplification tests (NAAT) & confirmation by

PCR assays for LGV-specific DNA

? Serology:

Complement fixation test ? lack sensitivity /

specificity
Microimmunofluorescent (MIF) antibody

testing to the L-serovar

? Frei intradermal test ? historical interest only;

based on positive hypersensitivity reaction
Treatment

? Recommended regimen

Doxycycline 100 mg twice daily for 21 days

? Alternative regimen

Erythromycin base 500 mg four times daily

for 21 days

Granuloma inguinale / venereum

? Chronic, destructive, granulomatous STI

caused by Gram negative organism

Klebsiella (Calymmatobacterium)

granulomatis

? Also k/a donovanosis

? Incubation period: Not precisely known; about

50 days in human experimental inoculation

studies

? The organism occurs inside large vacuolated

histiocytes in the form of "closed safety pin"
Clinical Features

? Initial lesion - a papule or subcutaneous nodule

that ulcerates

? Leads to large beefy-red, non-tender

granulomatous ulcers that bleed easily &

gradually extend

? Secondary infection - result in necrotic, foul-

smelling, deep ulcers

? May be followed by pseudo-elephantiasis

Investigations

Microscopy:
? Giemsa or Leishman's stain (crush smear

from ulcer) for Donovan bodies

? Clusters of blue-to-black organisms that

resemble `safety pins' within the vacuoles of

enlarged macrophages
Treatment

? Recommended regimen
Doxycycline 100 mg orally twice a day for 3

weeks and until all lesions have completely

healed

? Alternative regimens
OR Azithromycin 1 g orally once per week
OR Ciprofloxacin 750 mg orally twice a day
OR Erythromycin base 500 mg orally 4 times a

day

OR Trimethoprim-sulfamethoxazole one DS

(160/800 mg) tablet orally twice a day

Herpes genitalis

? Organism-Herpes simplex virus (HSV-2,

HSV-1)

? Incubation period: 2 days ? 2 weeks
? Primary episode: classically a group of

vesicular lesions leading to discrete multiple

painful ulcers

? Penile ulceration are most frequent on the

glans, prepuce and shaft of the penis

? Painful & last for 2?3 weeks if untreated
Clinical features

? In the female, similar lesions occur on the

external genitalia and mucosa of the vulva,

vagina & cervix

? Pain and dysuria are common
? First episodes are usually more severe than

recurrences

Investigations

? Microscopy

Tzanck smear ? nonspecific, multinucleate

giant cells

? Culture from vesicle fluid
? Detection of viral antigen by

immunofluorescence

? PCR for HSV DNA
Treatment

? First episode
Acyclovir 400 mg orally three times a day for 7-10

days

Or
Acyclovir 200 mg orally 5 times a day
Or
Valacyclovir 1 g orally twice a day
Or
Famciclovir 250 mg orally three times a day

Episodic therapy for recurrence

Acyclovir 400 mg orally three times a day for 5 days
Or
Valcyclovir 1 g orally once a day for 5 days
Or
Famciclovir 1 g orally twice a day for 1 day
Suppressive therapy for recurrence

If > 6 episodes/year
Acyclovir 400 mg orally twice a day
Or
Valcyclovir 500 mg or 1 g orally once daily
Or
Famciclovir 250 mg orally twice a day

Urethritis

? Characterized by findings of PMN leucocytes

in urethral smear or sediment in the first void

urine

- Gonococcal
- Non-gonococcal
Gonorrhea

? Gonorrhea - means "flow of seed"
? Albert Neisser identified the organism in 1879
? Neisseria gonorrheae - Gram negative

encapsulated aerobic diplococcus with pili

? Incubation period- 2-5 days

Clinical features

? Acute catarrhal inflammation of genital mucosa

? Men ? Acute inflammation of penile urethra-

urethritis

? Burning sensation, dysuria, discharge - yellow,

thick purulent discharge

? Females ? 50% may be asymptomatic- cervix

infection

? Lower abdominal pain, vaginal discharge or

dyspareunia

? Throat infection ? due to oral sex on an infected

partner- usually asymptomatic; may cause sore

throat
? May spread in ascending manner, causing

prostatitis, epididymitis, salpingo-oophoritis, PID,

later infertility

? DGI- pain and swelling in or around one or

several joints, fever and chills and skin lesions

? Ophthalmia neonatorum ? due to infected birth

canal during childbirth

Investigations

? Gram-stained smear ? PMNs with intracellular

G negative diplococci

? Culture ? Thayer-Martin, Chacko-Nair medium
? Ligase chain reaction ? 97% sensitivity
? Blood culture ? DGI, septicemic
Treatment

? Recommended regimen
Ceftriaxone 250 mg IM in a single dose OR
Cefixime 400 mg orally in a single dose
PLUS
Azithromycin 1 g orally in a single dose OR
Doxycycline 100 mg twice a day x 7 days

Nongonococcal Urethritis

Usual causative organisms:
? Chlamydia trachomatis [B,D,E,G,H,I,J,K]
? Mycoplasma genitalium
? Ureaplasma urealyticum
? Trichomonas vaginalis
? May co-exist with gonococcal infection
Clinical features

? Dysuria with odorless, mucoid, scanty discharge
? No diplococci but abundant PMNs
? > 5 pus cells / oil immersion field

Treatment

Azithromycin 1 g orally in a single dose
Or
Doxycycline 100 mg orally twice a day for 7 days

WITH (for Trichomonas)
Metronidazole 2 g orally in a single dose
Or
Tinidazole 2 g orally in a single dose
Vaginitis

Etiology

? Candida albicans and other species of Candida
? Trichomonas vaginalis
? Bacterial vaginosis

Candidal vulvovaginitis

? Normal flora of skin & vagina ? symptoms d/t

excessive growth of the yeast

? Balanoposthitis in males
? Risk factors: Pregnancy, DM, HIV infection /

AIDS, repeated courses of broad-spectrum
antibiotics, corticosteroids

? Most cases caused by C. albicans, others by non-

albicans sps e.g., C. glabrata
Clinical features

? Pruritus, frequency & burning micturition
? Dyspareunia
? Thick curdy white discharge
? Pre-menstrual flare
? Examination reveals thick cheesy plaques

Investigations

? 10% KOH mount: Pseudohyphae with budding

yeasts seen

? Vaginal pH is normal (4-4.5)
Treatment

? Uncomplicated vaginal candidiasis
OTC intravaginal agents
Clotrimazole 1% cream 5 g intravaginally daily for

7-14 days

Or Miconazole 200 mg vaginal suppository one

suppository for 3 days

Or Tioconazole 6.5% ointment 5 g intravaginally in

a single application

Oral agent
Fluconazole 150 mg orally in single dose

Trichomoniasis

? Caused by Trichomonas vaginalis ? a flagellated

anaerobic protozoan

? Itching / burning sensation with dyspareunia &

dysuria in females

? Frothy, foul-smelling yellowish-green vaginal

discharge

? `Strawberry cervix' ? petechiae on cervix
? May also cause upto 11-13% cases of NGU in

males ? usually asymptomatic
Investigations

? Saline wet mount: motile trichomonads in vaginal

discharge

? Vaginal pH - >4.5

Treatment

? Recommended regimen
Metronidazole 2 g orally in a single dose
Or
Tinidazole 2 g orally in a single dose
Bacterial vaginosis

? A disturbance in vaginal microbial ecosystem
? Caused by a mixed flora - Gardnerella

(Haemophilus) vaginalis, Mycoplasma hominis

and anaerobes

? Causes grey, homogenous discharge with

characteristic fishy odour

? Pruritus - not prominent

Diagnosis

? `Clue cells' - vaginal epithelial cells coated

with Gardnerella vaginalis (at least 20%)

? Whiff test: fishy odour on adding KOH

? Vaginal pH >4.5
Treatment

? Recommended regimen
Metronidazole 500 mg orally twice a day for 7 days
OR
Metronidazole gel 0.75%, one applicator (5 g)

intravaginally, once a day for 7 days

OR
Clindamycin cream 2%, one applicator (5 g)

intravaginally at bedtime for 7 days

Syndromic Management

? Use of clinical algorithms based on an STI

syndrome, the constellation of patient

symptoms and clinical signs, to determine

therapy

? Antimicrobial agents are chosen to cover the

major pathogens responsible for the particular

syndromes in a geographic area
Essential Components

? Syndromic Diagnosis and Treatment
? Education on Risk reduction
? Condom Promotion
? Partner Notification
? Counseling
? Follow-up

Each component is important for control

Advantages

Simple, inexpensive, rapid and implemented

on large scale

Requires minimum training and used by broad

range of health providers
Disadvantages

? Over diagnosis and over Rx (multiple

antimicrobials for single infection)

? Selection of resistant pathogens

? Does not address subclinical STI

Urethral Discharge

Urethral Discharge

Examine for Urethral Discharge: Milking of Urethra

Discharge seen

No Discharge seen

Rx for Gonorrhea and Chlamydia

Any other STI

F/u after 7 days

Use appropriate chart

Cured

Discharge persists

T/t regimen followed

regimen not followed

Refer to higher care

Repeat treatment &

Re-evaluate > 7 days
Genital Ulcer

No

No

Only vesicles present

GUD

Educate and counsel

Yes

Yes

Treat for Herpes

Treat for Chancroid and Syphilis

Treat for Syphilis if VDRL+

Treat for herpes if prevalence more than 30%

No

No

Ulcers healed

Ulcers improving

Refer

Yes

Yes

Educate and counsel

Continue for 7 more days

Inguinal Bubo

Enlarged or painful inguinal lymph nodes

History & examine

No

Ulcer(s) present

Yes

Rx for LGV + Chancroid

As in genital ulcer chart

14 Days

Responding to treatment

No

Refer to higher care centre

Yes

Presume cured
Vaginal Discharge/ Itch/ Burning

History

No

No

Vulvul erythema

Any other STI

Educate

Yes

Yes

Appropriate chart

Lower abdominal pain

Lower abdominal pain chart

No

Yes

High GC/CT prevalence

Treat for Gonococci/Chlamydia/

bacterial Vaginosis/Trichomonas

No

Treat for bacterial

Yes

Vulvul edema / erythema

Treat for Candida

Vaginosis

and Trichomonas

No

Educate

This post was last modified on 07 April 2022