The vaginal flora of a normal, asymptomatic reproductive-aged woman includes multiple aerobic or facultative species as well as obligate anaerobic species




  • Lactobacillus spp.
  • Diphtheroids
  • Staphylococcus aureus
  • Staphylococcus epidermidis
  • Group B Streptococcus
  • Enterococcus faecalis
  • Staphylococcus spp.
  • Actinomyces israelii


  • Escherichia coli
  • Klebsiella spp.
  • Proteus spp.
  • Enterobacter spp.
  • Acinetobacter spp.
  • Citrobacter spp.
  • Pseudomonas spp.


Gram-positive cocci

  • Peptostreptococcus spp.
  • Clostridium spp.

Gram-positive bacilli

  • Lactobacillus spp.
  • Propionibacterium spp.
  • Eubacterium spp.
  • Bifidobacterium spp.


  • Prevotella spp.
  • Bacteroides spp.
  • Bacteroides fragilis group
  • Fusobacterium spp.
  • Veillonella spp.


  • Candida albicans and other spp.

Of these, anaerobes predominate and outnumber aerobic species approximately 10 to 1. These bacteria exist in a symbiotic relationship with the host and are alterable, depending on the microenvironment. They localize where their survival needs are met and have exemption from the infection-preventing destructive capacity of the human host. The function of this vaginal bacterial colonization, however, remains unknown.


The patient is a female patient aged 13–35 years with abdominal pain, adnexal tenderness, and cervical motion tenderness (all three should be present). Patients also have at least one of the following: elevated sedimentation rate, leukocytosis, fever, or purulent cervical discharge. Treat with more than one antibiotic (e.g., cefoxitin/ceftriaxone and doxycycline on an outpatient basis; clindamycin and gentamicin on an inpatient basis) to cover multiple organisms (e.g., Neisseria gonorrhoeae, Chlamydia spp., Escherichia coli ). In patients with a history of intrauterine device use, think of Actinomyces israelii ( Table 4-1 ).

  • PID is the most common cause of preventable infertility (causes scarring of the fallopian tubes) and the most likely cause of infertility in a woman younger than 30 years of age with normal menstrual cycles.

  • Watch for progression to tubo-ovarian abscess (palpable on exam and/or visible on ultrasonography [US]) and abscess rupture. Rupture is treated with emergent laparotomy and excision of the affected tube (with unilateral disease) or hysterectomy and bilateral salpingo-oophorectomy (with severe bilateral disease). An unruptured abscess may respond to antibiotics (unlike many abscesses) alone, with percutaneous drainage sometimes used.


A 19-year-old woman presents with a purulent cervical discharge. Culture reveals gonorrhea. What should the treatment be? Ceftriaxone plus doxycycline or azithromycin (the doxycycline or azithromycin is given to treat presumed chlamydial coinfection). The reverse is not true, however; do not treat patients with chlamydial infection for gonorrhea unless you know they have both.



A 24-year-old woman with purulent vaginal discharge tests positive for Chlamydia by polymerase chain reaction (PCR testing). A urine human chorionic gonadotropin (HCG) test is positive for pregnancy. What is the preferred treatment? Erythromycin is preferred over doxycycline in pregnant or breast-feeding patients because doxycycline has the potential for fetal harm including tooth discoloration and bone malformation.


A woman presents with a malodorous vaginal discharge, and a fishy odor is evident when you perform a potassium hydroxide preparation of a swab sample. How should you handle treatment of the woman’s sexual partner? The patient is infected with Gardnerella spp. You do not need to treat the patient’s sexual partners. The same is true for candidal infection. Remember to treat partners and give counseling (e.g., condoms) for the other infections in the chart provided earlier.

Table 4-1
Vaginal Infections
Candida albicans “Cottage cheese” discharge, pseudohyphae on KOH preparation, history of diabetes mellitus, antibiotic treatment Azole cream vaginal. With recurrent infection or in HIV+ patient, use oral azole
Gardnerella vaginalis Malodorous discharge; fishy smell on KOH preparation, clue cells Metronidazole
Trichomonas vaginalis Pale green, frothy, watery discharge; motile protozoa on wet mount; “strawberry cervix”; sexually transmitted Metronidazole
Treat partners
Chlamydia trachomatis Most common sexually transmitted disease; dysuria, positive PCR-DNA test, culture, or antibody test Doxycycline or azithromycin
Neisseria gonorrhoeae Mucopurulent cervicitis; gram-negative bugs on Gram stain, positive PCR-DNA test Ceftriaxone or cefixime
Herpes simplex virus Multiple shallow, painful ulcers; recurrence and resolution Acyclovir, valacyclovir
Human papillomavirus Genital warts, koilocytosis on Pap smear; high risk include types 16, 18. Low risk include types 6, 11 Many—observation, acid, cryotherapy, laser, podophyllin)
Molluscum contagiosum Characteristic appearance of lesions (pearly papule with central umbilication), intracellular inclusions Many—observation, curettage, cryotherapy
Pediculosis “Crabs”; itching, lice on pubic hairs Permethrin cream
Primary syphilis Painless chancre, spirochete on dark field microscopy Penicillin
Secondary syphilis Condylomata lata, maculopapular rash on palms, serology Penicillin
DNA, Deoxyribonucleic acid; KOH, potassium hydroxide; PCR, polymerase chain reaction.


Preventable with vaccine


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