STIs Flashcards
What is a commensal micro-organism?
A micro-organism that derives food or other benefits from another organism without having an impact on it
What is a pathogen?
A micro-organism that can cause disease
What is an infection?
The invasion of all or part of the body by a micro-organism
What is a sexually transmissible organism?
a virus, bacteria, protozoan, insect, or arthropod which can be spread by sexual contact
What is a sexually transmitted infection?
An infection by a pathogen which is sexually transmissible and which is unlikely to be transmitted by non-sexual means
What are examples of organisms causing STIs?
Neisseria gonorrhoeae
Human papilloma virus
What is a sexually transmitted disease?
A disorder of structure or function caused by a sexually transmitted pathogen
What are examples of sexually transmitted bacteria?
Chlamydia trachomatis - chlamydia
Klebsiella granulomatis - Granuloma inguinale
Mycoplasma genitalium
What are examples of sexually transmitted viruses?
HSV - herpes simplex virus
HIV - Human immunodeficiency virus
HPV - human papilloma virus
Molloscum contagiosum virus
What are examples of sexually transmitted parasites?
Pthirus pubis
Sarcoptes scabei
Trichomonas vaginalis
What are characteristics of STIs?
Transmissible
Asymptomatic most of the time
All manageable but not always curable
Avoidable
What are examples of sexual contact in order of increasing risk of infection?
Mutual masturbation Touching someone else's genitals with your own Oral sex Vaginal sex Anal sex Group sex
What are general symptoms of STIs?
Fever
Rash
Lymphadenopathy
Malaise
What are adverse outcomes of STIs?
Infertility
Cancer
Adverse pregnancy outcomes
Why may STI reports be increasing?
Increased number of partners per person Increased concurrent partners More people having anal sex More MSM More people being tested and more accurate tests
Why is sexual history necessary?
Determining possible cause of symptoms
Detect high-risk behaviour and advice to reduce future risk
Tracing contacts
What are important questions to ask in the sexual history?
When did you last have sexual contact? Casual or regular partner? Male or female? Can be useful to ask about nature of sex act Did you use condoms? Other contraception Nationality of contact
What is the risk assessment for a man?
Have you ever had sexual contact with a man?
Have you injected drugs?
Sexual contact with anyone who’s injected or anyone from outside the UK?
Medical treatment outside the UK?
Involvement with sex industry?
What are common presenting complaints of genital symptoms?
Discharge from an orifice Pain from somewhere Rashes Lumps and swellings Cuts, sores, ulcers Itching Change in appearance Vague sense of things not being right
What are microbial conditions that are not regarded as STDs?
Vulvovaginal candidosis Bacterial vaginosis Balanoposthitis Tinea cruris Erythrasma Infected sebaceous glands Impetigo Cellulitis
What is vulvovaginal candidosis?
Thrush
What is the most common causative organism of vulvovaginal candidosis?
Candida albicans
What are symptoms of vulvovaginal candidosis?
Itch
Thick ‘cottage cheese’ discharge
Who is susceptible to vulvovaginal candidosis?
Diabetics Patients taking oral steroids Immune suppressed patients Pregnancy Sexually active
How is vulvovaginal candidosis diagnosed?
Characteristic history
On examination - fissuring, eryhtema with satellite lesions, characteristic discharge
What investigations are done if vulvovaginal candidosis is suspected?
Gram stain
Culture
How is vulvovaginal candidosis treated?
Azole antifungals - clotrimazole, fluconazole
What are symptoms of bacterial vaginosis?
Watery grey discharge
May be worse after period or sex
Sometimes sore/itch from dampness
What are potential complications of bacterial vaginosis?
Associated with endometritis
Associated with premature labour
Increase risk of HIV acquisition
How is bacterial vaginosis diagnosed?
Characteristic history
On examination - Thin, homogenous discharge
pH
Gram stain of smear of vaginal discharge
How is bacterial vaginosis treated?
Antibiotics - metronidazole
Clindamycin
Probiotics
Vaginal acidification
What organism causes gonorrhoea?
Neisseria gonoorhoeae
What are symptoms of gonorrhoea?
Males - Thick, profuse, yellow discharge, dysuria
Females - Vaginal discharge, dysuria, intermenstrual/post-coital bleeding
What are complications of gonorrhoea?
Acute monoarthritis
Gonococcal infection
Male - epididymitis
Female - Pelvic inflammatory disease, Barothlin’s abscess
How is gonorrhoea diagnosed?
Gram stained smear from urethra/cervix/rectum
Culture of swab from exposed site
How is gonorrhoea treated?
Ceftriaxone 1g IM
Can also treat according to antibiotic sensitivities
What organism causes chlamydia?
Chlamydia trachomatis
What are symptoms of chlamydia?
Conjunctivitis
Male - Slight watery discharge, dysuria
Female - Vaginal discharge, dysuria, intermenstrual/post-coital bleeding
What are complications of chlamydia?
Reactive arthritis
Urethritis/cervicitis + conjunctivitis + arthritis
Male - epididymitis
Female - Pelvic inflammatory disease - ectopic pregnancy, pelvic pain, infertility
How is chlamydia diagnosed?
First void urine in men, cervical, urethral, or rectal swab
Tested using Nucleic Acid Amplification Test
How is chlamydia treated?
Doxycycline 100mg twice a day for a week
What is herpes caused by?
Herpes simplex virus types 1 and 2
What are symptoms of herpes?
Recurring symptoms - monthly or annually Burning/itching then blistering, then tender ulceration Tender inguinal lymphadenopathy Flu like symptoms Dysuria Neuralgic pain in back, pelvis, and legs
How is herpes treated?
Aciclovir 400mg
What organism causes trichomoniasis?
Trichomanas vaginalis
What are symptoms of trichomoniasis?
Male - usually asymptomatic
Female - Profuse thin vaginal discharge - greenish, frothy, foul smelling, vulvitis
What are complications of herpes?
Autonomic neuropathy
Neonatal infection
Secondary infection
What are complications of trichomoniasis?
Miscarriage
Preterm labour
How is trichomoniasis treated?
Metronidazole
What causes anogenital warts?
HPV types 6 and 11
What are symptoms of anogenital warts?
Lumps with surface texture of a small cauliflower
Occasionally itching or bleeding especially if perianal or intraurethral
