STDs

Question 1

HSV (basics, presentation of 1 and 2, dx)

Answer 1

• Dbl stranded DNA leading to lifelong infection
• Lytic (new) and latent growth
• HSV-1
  
  • Very common but only 18% chance recurrence
  • Vesicular lesions –> painful skin erosions, gingivosomatitis, keratoconjunctivitis, herpetic whitlow (fingers - dentists), genitals too
  • Serious - encephalitis (temporal lobe), disseminated if immune-supp
• HSV- 2
  
  • Less common but recurrences more likely 60% (usually primary outbreak is worse in appearance)
  • Same manifestations as HSV-1 but more commonly genital skin or mucous membranes
  • Can be transmitted w/o lesions (asymptomatic shedding)
  • Vertical transmission
• Dx - Tzanck smear (ID multi-nucleated giant cells on skin scraping), viral cx, PCR`

Question 2

HSV Tx

Answer 2

• Acyclovir - nucleoside analogue that inhibits DNA replication (only in lytic phase when HSV rapidly replicating)
  - Given in IV for encephalitis or disseminated form
• Valacyclovir - pro-drug changed to acyclovir in liver (so less frequent dosing)
  • Both can be used for primary and suppression of outbreaks

Question 3

Normal Vaginal Environment

Answer 3

• 1-4 cc white or transparent d/c per day (changes w/ ovulation, pregnancy and OCPs); usually odorless
• Secretions formed by mucoid endocervical secretions (epithelial cells sloughed, normal bacteria, transudate)
• Wet mount - micro slide w/ some d/c and normal saline; normally see epithelial cells w/ clear margins and many lactobacilli (thin rods)
• pH < 4.5 b/c lactobacilli produce lactic acid which dec susceptibility to infections; some strains prod hydrogen peroxide
• Vaginal washing and recent abx use dec lactobacillus

Question 4

Trichomonas

Answer 4

• Presentation - strawberry cervix, frothy d/c, see protozoa under microscope, irritation and d/c, BUT commonly asymptomatic
• Dx - microscopy or more sensitive NAAT (nucleic acid amplification)
• Tx - metro sngl dose (give to both partners, wait 7 days for intercourse, test for cure in 3 mo)

Question 5

Bacterial Vaginosis (presentation, dx, tx)

Answer 5

• Presentation - clue cells on microscopy (epithelial cells w/ irregular, stippled borders), fish odor d/c
• Associated w/ certain bacteria but it is a syndrome regardless of specific bacteria; characterized by dec lactobacillus and inc anaerobes and Gardnerella
• Associated w/ multiple partners, new partner, lack of condom use (but do not know exact mechanism of transmission)
• Dx - 3/4 Amstel’s Criteria
  - 1- discharge (homogenous, thin, white, coating walls)
  - 2- clue cells on micro
  - 3- pH > 4.5
  - 4 - Fishy odor of d/c after addition of 10% KOH (whiff test)
• Tx - metro (need 7 day dose), MetroGel, clindamycin cream

Question 6

Yeast Vaginitis (presentation, predispositions, dx, tx)

Answer 6

• Presentation - itching, burning, redness, hyphae on KOH slide (branched), red plaques w/ edema and excoriations and raised white or yellow adherent plaques on physical exam
• COMMON (75% women have 1 episode); most common is Candida albicans
• Predisposition if… diabetes, pregnancy, obesity, abx use, steroids, immunosuppression
• Dx - KOH prep, normal pH (no change to lactobacilli), yeast cx (esp if worried about non-Candida yeast)
• Tx - topical azoles or oral flucanozole; f/u if symptoms persist or reccur

Question 7

Recurrent Yeast Vaginitis (definition, risks, tx)

Answer 7

• Recurrent / severe = 4+ episodes in 1 yr
• Risks - DM, immune-suppression, something other than Candida
• Std tx w/ azoles followed by suppression w/ weekly fluconazole for 6 mo

Question 8

Chlamydia

Answer 8

• most common infection (esp < 26 yo)

Can cause … cervicitis, urethritis, proctitis, Bartholin’s gland abscess, neonatal conjunctivitis, pneumonia

• 70% asymptomatic but cause scarring –> PID, ectopic pregnancy, infertility (annual screening for women < 26 or high risk behavior)
• Dx - based on symptoms then confirm w/ urine or swabs sent for NAAT, ELISA
• Tx - azithromycin 1 day or doxy 7 days (treat partner too); abstain from sex for 7 days after dose

Question 9

N. gonorrhea

Answer 9

• 2nd most common (gram neg diplococci)
• 50% asymptomatic but can cause … cervicitis, urethritis, proctitis, Bartholin’s gland abscess, pharyngitis, neonatal opthalmia
• Also recommend annual screening if < 26 yo or high risk sex behaviors
• Dx - based on symptoms then confirm w/ urethral gram stain, cx, NAATs
• Tx - IM ceftriaxone + azithromycin or doxy (covers chlamydia too) - always co-treat b/c commonly co-occur

Question 10

Fitz-Hugh-Curtis syndrome

Answer 10

Complication of PID; abdominal adhesions

Question 11

PID (causes, dx, tx)

Answer 11

POLYMICROBIAL (often ID chlamydia and gonorrhea)

• Dx - CLINICAL (want to treat all); sexually active woman w/ ab pain and 1 of the following …
  
  • Uterine tenderness, adnexal tenderness, cervical motion tenderness
• Tx - cover chlamydia and gonorrhea OR inpatient if more severe (cephalosporin and doxy or clindamycin)