STI Flashcards
Discuss risk factors for the development of STI
High risk sexual practices
- Multiple sex partners
- Substance abuse
- Commercial sex workers
- Men who have sex with men
- unsafe sex practices
Socio-economic factors
- adolescents and young adults
- minorities
- low socioeconomic status
Discuss why the management of STDs can be challenging in the ED ( 4 points)
1) clinical presentation is highly varibale
2) avialble diagnostic test have limited senisitivty and results are usually delayed
3) compliance with treatment follow-up and partner notification is often poor
4) misdiangosis and suboptimal treatment can result in serious sequalae
List DDX of genital ulcers
Herpes Primary syphilis Chancroid Lymphogranuloma venerum Granuloma inguinale Trauma Neoplasm Behcets disease
Discuss DDX of genital discahrge
Gonorrhea Chlaymydia Nongonococcal urethritis PID Trichomoniasis Bacterial vaginosis Candida vagintiis Foreign body
Discuss DDX of epithelial cell lesions
Genital warts Secondary sypillis Molluscum contagiosum Neoplasm Nevi Skin tag
Discuss DDX of ectoparasites
Pubic lice
scabies
other lice
Ticks
Discuss Herpes infection
Lifelong infection caused by one of two types
Sexual transmission occurs more commonly with HSV2
Transmission occurs through viral contact with a break in the skin or itnact mucous membrane
The virus ascends to the dorsal root ganglia where it becomes latent but may reactive periodically
Discuss management of herpes infection
Antiviral therapy is not curative but has been shown to decrease the duration and severity of symptoms
Prompt initiation of antiviral treatment is key to its success
Primary episode
- aciclovir 400mg PO TDS for 7-10 days
- Valacyclovir 1000mg PO BD for 7-10 days
Recurrent episodes
- aciclovir 400mg PO BD for 5 days
- valacyvlovir 1000mg daily for 5 days
What is the causitive organism of syphilis
Humans are the only known host for treponema pallidum the spirochete that causes syphilis
Discuss clinical features of syphilis
Average incubation is 21 days but can range from 3-90 days
Primary syhpilis
- Manifested by a painless papule at the site of inoculation
- the lesion ulcerates froming the chancre of primary syphilis
- relative painless clean based ulcer with well demarcated edges measuring appproximatley 1-2cm in size
- Will heal spontaneously over the course of 3-6 weeks
Secondary
- develops in 25% of cases of primary syphilis
- Rash diffuse involving the face trunk, extremities including the p[lams and soles of the feet. Lesions are variable may be macular papular scaly or pustular in appearance
- generalised lymphadenopathy
- mucous membrane lesions and systemic features
- Condyloma lata which resembles genital warts are broad based papular lesions that are common in secondary syphiliis
Latent:
- Serological evidecne of syphilis infection in the absence of any clinical signs or symptoms
- latent infection acquried within 12 months is defined as early and those more than 12 months are late latent
- generally not infective with the significant expection vertical transmission in pregnant women
- can persist indefinitely beofre progressing to tertiary syphilis
Tertiary
- Cardiovascular manifestation: aortitis, aortic aneurysm
- gummatous disease: granulomatous lesions, called gummas, which are characterized by a center of necrotic tissue with a rubbery texture. They form in the liver, bones, and testes but may affect any organ
- Neurosyphilis refers to infection of the CNS manifesting in altered mental status, meningitis, cranila nerve abnormalities, CVA, peripheral neuropathy and auditory and ophtlamic abnormalities
Discuss IX of syphilis
Veneral disase research lab and the rapid plasma reagin PCR test are both requried for proper diagnosis of syphilus
Discuss management of syphilis
T.pallidium is highly sensitive to penicillin
A single dose of long acting benzathine penicillin G 2.4 million units IM is curative in most cases.
Signfiiacnt pencillin allergy can be treated with doxy or tetracycline for 2 weeks.
The Jarish Herxheimer reaction is an acute worsening of symptoms that may develop mafter antibiotic therapy is iniaited - patient typically reports worsening of myalgias and fever within 24 hours of treatment.
Discuss chancroid
An ulcerating STD caused by the gram negative organism haemophilus ducreyi.
Most commonly seen in the developing world - like other ulcerative STDs chancroid is a cofact for the transmission of HIV
After less than week a tneder erythamtous papule develops at the site of inoculation. The initial lesions rapidly ulcerates and multiple painful ulcers subsequently develop.
Typically have an irregular inflamed and dirty appearance compated to the well circumscribed clean based chancre of syphillus
Single dose therapy with either azirthromycin or ceftriaxone is recomended
Discuss Urethritis
Can occur in both men and women
Generally divided into gonococcal urethritis and non gonococcal
When present syumptoms include, dysuria, urethral pruritis and urethral discahrge
Abscence of discharge does not exclude the diagnosis
Diagnosis can be made from any one of the following
1) Mucoid mucopurulent urethral discharge
2) gram stain of urethral discharge containing two or more WBC
3) first pass urine containing more than 10 WBC on high power field
4) positive leukocyte esterase test on first void urine
Discuss cervicitis’
Characterised by the presence of purulent or mucopurulent discharge from the endocervix and the presence of cervical friability.
Many women with cervicitis are asymptomatic
-Cervical friability is demonstarted when endocervical bleeding is easily idnuced with gental passage of a swab through the cervical os.
Gonorrhea and chlaymdia are the most common causes but tichomonas and HSV also cause.
Women with cervicitis complaing of abnormal vaginal discharge, dyspareunia and postcoital vaginal bleeding.
Discuss gonorrhea
Second most common STD
Humans are the only reservoir for the causative organism Neisseira gonorrheoa
Incubation is 3-7 days
Common complaints are of urethral dischareg and dysuria. Discharge usually copious and purulent
Women with gonococcal cervitis are usually asymptomatic until ascending infection develops
Gonococcal proctitis presents with rectal pain, tenesmus, rectal discharge and bleeding.
Gonococcal pharyngitis usually aymptomatic but may complain of sore throat with tonsillar erythema and cervicla lymphadenoapthy
Conjunctivitis most common seen in infants born to infected mothers - as infants are now routinely prophylaxed at birth gonoccal conjunctivits is now more common in adults.
Disseminated gonococcal infection resutls from haematogenous spread of N. gonorrhoeae. May occur in the absece of any signs or symptoms of intitial infeciton. Charcteristic finding include rash, polyarthralgias, tenosynovitis and septic arthritis,
Discuss IX of gonorrhea
Gram stain
Culture and nucleic acid amplification
Discuss treatement of gonorrhoea
Ceftriaxone remains the drug of choice for treatment. A single dose of 500mg is recommended for most cases of gonococcal urethritis, cervicitis, proctitis and pharyngitis
Cocomitant therapy with a single dose of azithromycin 1 gram PO is recommended to provide synergistic cover and for coverage against possible chlaymidal coinfection
Discuss chlamydia
Caused by C trachomatis an obligate intracellular organism. Approxijmatly 50% of men and 70% of women who are infected are asymptomatic
Common cause of NGU - when present discharge is typically scnat and less purulent than that seen with gonorrhoea. Dysuria is less pronounced and presentation is often delayed.
Cervicitismay present with mucopurelent cervical disharge or post coital bleeding but is most commonly asymptomatic . If untreated can progress to upper tract infection including epididymitis and orchitis in men and PID in women.
Treatment consist of a single dose of 1g azithromycin or a 7 day course of doxy 100mg BD - azithromycin is the drug of choice in pregnancy - again likley treat for both gonorrea and chlaymydia with 500mg of cef IM `
Discuss microbiological causes of Non gonococcal urethrtiis
C trachomatis, trichomonas vaginalis, mycoplasma genitalium and other mycoplasma sepscia, ureaplasma species.
Discuss Trichomoniasis
Trichomonas vaginalis is the flagellated protozoan organism repsonsible for trichomoniasis the most common curable STD
Women are typically more symptomatic than men
Usually cases mild disease but significant morbidity can occur – assocaited with PID, preterm birth, prostattis, epididymitis and increased susceptibility to HIV
Causes vaginal dsiahrge calssically malodorous forthy and greenish yellow in colour. Dysyruia and frequency, dyspareunia and post coital bleeding in the setting of cervicitis
Single dose metronidazole 2g PO is highly effected- alternatively 500mg BD can be used
Discuss PID
An scedning infection that begins at the leve of the endocervix but progresses to the upper reproductive tract causing endometritis, salpingitis and peritonitis.
Classically caused by chlamydia and gonorrhea – polymicrobial involvment is common,with anaerobes enteric organism vaginal flora and other STDs often impicated in PID.
Discuss clinical features
Spectrum of disease ranging from asymptomatic infection to severe illness with associated peritonitis and systemic toxicity.
Dyspareunia, abnromal vaginal discharge or bleeding, dysuria and fever are all common.
Discuss IX of PID
The diagnosis of PID should be considered and presumptive treatment initiated in any pregnant women at risk for STDs who present with lower abdominal pain or pelvic pain wihtout clear other cause and if one or more of the following are present
1) cervical motion tenderness
2) uterine tenderness
3) adenexal tenderness
These criteria have low sensitivty but high specificity - the use of the following criteria improves sepcificity but decrease sensitivity
-mucopurlent discharge
-cervical friability
-oral temp >37.8
ESR raise
WBCE on microscpy of vaginal secretions
Lab confirmation of gonrorrhea or chlaymydia
NAATs for gonorrhea and chlaymydia are recommonded and exclusion of pregnancy is necessary
Discuss disposition and management of PID
Indications for admission
- Severe clinical illness ( high fever, nausea, vomiting severe abdominla pain)
- Complicated PID with pelvic abcess
- Possible need for ivnasive diagnositc evaluation for alternate aetiology
- inability to tolerate oral medication
- pregancny
- lack of response
- concern for non adeherance to therapy
OPD - Ceftriaxone 500mg IM + azithromycin 1g followed by subsequent 1g a week later or doxy BD 14 days + metronidazole 500mg BD 14 days
In patient
-Ceftriaxone IV 2g + azithromycin 500 mg IV plus Metronidazole 500mg IV BD
All pateitn shouold have supportive measures including analgesic, antipyretics and hydration. Abstain from sex until symptoms ahve resolved and AB course has been completed by both patient and partner
Discuss bacterial vaginosis
Most common cause of abnormal vaginal discharge in the US. Although bacterial vaginosis is not considerd to be an STD. Bacterial vaginosis is due to an alteration in the vaginal flora with replacement of normal lactobacillus species by polymicrobial group of orgnaisms including gardnerella vaginalis, anaerobes and others.
Many women are asymptomatic – symptomatic women complain of malodorous thin whitish vaginal dsicharge. A fishy odor is often rpeorted
PH of vaginal fluid is greater than 4.5
Treatment is recommended for all symptomatic women not for asymptomatic.
1) metronidazole 500mg PO Bd for 7 days
2) metronidazole gel 0.75% 5 G intravaginally at bedtime for 7 days
Discuss vulvovaginal candidiasis
Candida albicans
Lots of topically antifungals like miconazole, fluconazole orally but cannot be taken in pregnancy
