Genital Infections Flashcards
How is vaginal pH maintained?
- Oestrogen / Progesterone stimulate secretion of glycogen.
- Lactobacilli convert glycogen into lactic acid.
- Lactic acid production maintains vaginal pH at 3.5-4.5.
Outline gram positive bacteria and how they stain.
Gram-positive bacteria have a thick meshlike cell wall made of peptidoglycan and as a result are stained purple by crystal violet.
Outline Gram-negative bacteria and how they stain.
Gram-negative bacteria have a thinner layer so do not retain the purple stain.
What is the condition described?
Offensive fishy smelling vaginal discharge, not associated with soreness, itching, or irritation.
Thin, white, homogeneous discharge, coating the walls of the vagina and vestibule.
Bacterial vaginosis
Summary of Bacterial vaginosis:
What bacteria cause bacterial vaginosis?
This condition is characterized by replacement of vaginal lactobacilli with predominantly anaerobic microorganisms such as Gardnerella vaginalis and Mobiluncus morphotypes.
What are the risk factors of bacterial vaginosis?
Vaginal douching Overwashing Receptive cunnilingus Black race Recent change of sex partner Smoking Presence of an STI e.g. chlamydia or herpes.
What is the likely condition described?
Itchy white discharge?
Vulvovaginal candidiasis (thrush)
What is the most common cause of Vulvovaginal candidiasis (thrush)?
Candida albicans >90%
What are the symptoms of Vulvovaginal candidiasis (thrush)?
- Vulval itching
- Vulval soreness
- Vaginal discharge
- Superficial dyspareunia
- External dysuria
What is the likely diagnosis in a women with these symptoms?
- 10-50% are asymptomatic
- Profuse vaginal discharge
- Vulval itching
- Dysuria
- Strawberry cervix
Trichomonas vaginalis
Trichomonas vaginalis
Trichomoniasis is a type of sexually transmitted infection caused by a tiny parasite.
Symptoms of trichomoniasis include pain when peeing, sore or itchy genitals, and abnormal discharge from your vagina or penis.
What are the symptoms of chlamydia?
- Post coital / intermenstrual bleeding
- PV discharge
- Lower abdominal pain
- Dysuria
What are the complications chlamydia can cause?
- Cervicitis
- Pelvic Inflammatory Disease
How does Pelvic inflammatory disease present?
- Lower abdominal pain, typically bilateral.
- Deep dyspareunia.
- Abnormal vaginal bleeding, including post coital, intermenstrual and menorrhagia.
- Abnormal vaginal or cervical discharge, often purulent.
How does chlamydia present in men?
- Asymptomatic ~50%
- Urethral discharge
- Dysuria
What are the complications of chlamydia in men?
- Epidydimo-orchitis
- Non specific urethritis
- Conjunctivitis (adult / newborn)
• Sexually Acquired Reactive Arthritis (SARA) (Reiter’s syndrome).
• LGV
LGV
Lymphogranuloma venereum (LGV) is an ulcerative disease of the genital area. It is caused by Chlamydia trachomatis.
What is Sexually Acquired Reactive Arthritis (SARA) (Reiter’s syndrome).
Sexually acquired reactive arthritis ( SARA) is a reactive arthritis caused by an immune reaction to an infection, often a sexually transmitted infection. It is caused by immune complexes ( so antibodies that fight infection and proteins from the infection) being deposited in the joints.
What gram stain is chlamydia?
Gram-negative bacteria
- red
What are the symptoms of LGV?
Within a few weeks of becoming infected, most people get painful inflammation in the rectum (known as ‘proctitis’) with bleeding, pus, constipation or ulcers.
You can also get a fever, rash and swelling in your groin, armpit or neck.
What condition does this triad present in?
SARA - Sexually acquired reactive arthritis aka Reiter’s syndrome.
What is the likely diagnosis in a male patient who presents with green offensive discharge?
- gram negative stain
Neisseria gonorrhoeae
What are the symptoms of Neisseria gonorrhoeae?
Urethral discharge
Dysuria and increased frequency
What are the complications of Neisseria gonorrhoeae?
• Prostatitis • Epididymitis • Acute urethritis • Later urethral stricture • Sexually acquired reactive arthritis (SARA) • Disseminated gonococcal infection
How does Neisseria gonorrhoea present in women?
- Endocervical discharge – asymptomatic ~50%
- Increased vaginal discharge in ~50%
- Dysuria – 12%
- Rectal (direct spread) – asymptomatic
- Pharyngeal – asymptomatic >90%
Can lead to pelvic inflammatory disease in women.
What is the likely diagnosis in a male presenting with clear discharge?
- Gram negative bacteria.
Non gonococcal urethritis
Non gonococcal urethritis
NGU is an infection of the urethra caused by pathogens other than gonorrhea.
What pathogens can cause NGU?
Treponema pallidum causes what condition?
Syphillis
Treponema pallidum is gram what?
Gram negative
What does syphilis effect?
Syphillis affects the skin and mucus membranes of the genitalia and mouth.
How is syphilis transmitted?
- Acquired syphillis - T.pallidum enters the body through body fluids.
- Congenital syphillis - Mother has syphillis.
What are the three stages of acquired syphilis?
- Primary - Early localized - spirochetes destroy skin leading to ulcer formation know as syphilitic chancres (painless).
- Secondary stage - spirochetes enter the blood stream causing generalised lymphadenopathy. Can present with a non-itchy maculopapular rash.
- Latent - dormant / assymptomatic phase.
- Early latent - within a year of infection.
- Late latent - After a year.
- Tertiary syphillis.
What happens in the tertiary phase of syphillis?
Type IV Hypersensitivity reaction
Spirochetes in the blood cause a huge immune response from tcells.
T cells recruit macrophages causing release of pro-inflammatory cytokines.
This inflammatory response leads to swelling, warmth, edema, redness and a fever.
Tertiary syphillis can lead to organ damage.
Cardiovascular syphilis:
Presents with endarteritis - inflammation of the vaso vasorum of the aorta. This leads to aortitis which can progress to aortic aneurysm.
Presentation of syphilis:
Congenital syphilis
Syphilis summary:
What is screened for in sexual health clinics for assymptomatic patients?
- Chlamydia trachomatis
- Neisseria gonorrhoeae
- HIV
- Syphilis
What is screened for in symptomatic patients in a sexual health clinic?
Identify!
Treoponema pallidum - the syphilis spirochete!
Candida albicans gram stain?
Gram positive
What is the bacteria shown in this gram stain?
Neisseria gonnorrhoea.
