Chapter 13: STIs & Pregnancy Flashcards
STIs
Infections transmitted by sexual contact by genital organs.
STIs caused by
Viruses, bacteria, fungi, parasites. No vaccines for most STIs, no future immunity after infection.
Lifestyle choices for STIs
Protected sex, abstinence, don’t share implements with blood (needles), be aware of warts, sores.
Chlamydia
Caused by highly specialised bacterium, Chlamydia trachomatis transmitted by sexual contact with infected. Both men and women can be infected. No symptoms.
Chlamydia in males
Males may develop nonspecific urethritis (NSU). Symptoms: yellow mucus discharge from penis, urination pain. If untreated, bacterium spreads to epididymis causing epididymitis (inflamed, pain), testes (infertility, both testes infected).
Chlamydia in females
Most infected women have no symptoms. If untreated may lead to infertility, arthritis. Symptoms: pelvic inflammatory disease (PID) in uterus, uterine tubes causes blocks by scar tissue.
Chlamydia in pregnant females
May cause implantation outside uterus (ectopic pregnancy) causing premature, stillborn child. If infected woman is pregnant, 70% chance disease passed to foetus.
Diagnosis of chalmydia
Chlamydia can be cured. Urine test in males and females, genital swab.
Treatment of chlamydia
Antibiotics. Sometimes bacteria can’t be completely eliminated.
Gonorrhoea
Affects mucus membranes of excretory and reproductive systems. Caused by bacterium, Neisseria gonorrhoeae transmitted by sexual contact with infected. Affects both males and females, symptoms appear 2–10 days after infection (incubation).
Gonorrhoea in males
Urethra inflammation results burning feeling in penis when urinating, yellow discharge from penis. Untreated, urethra may permanently narrow (urination difficulty) and infection may spread: testes (infertility), joints (arthritis).
Gonorrhoea in females
No symptoms. Urethra or cervix infected, so babies can be infected. Females may have disease months before, then pain appears. Untreated, infection spreads to uterine tubes causing blockage = infertility.
Diagnosis of gonorrhoea
Gonorrhoea can be cured. Urine tests (male urethral, female endocervical, vaginal), genital swab.
Treatment of gonorrhoea
Antibiotics, but gonorrhoea types developed antibiotic resistance.
Syphilis
Caused by thin bacterium, Treponema pallidum. Transmitted by sexual contact. Has 4 stages.
Primary stage
Bacterium enters skin. Incubation (spread, multiply) 10 days-10 weeks. Symptom: Small sores (chancres) on genitals, lip.
Secondary stage
Few weeks after, maybe delayed 12 months. Symptoms: rash, sores, mild fevers. Patient is highly infectious and lasts 2 years, symptoms eventually disappear.
Latent stage
No symptoms, but still infected. Lasts many years, sometimes lifetime. Now, infection can’t be passed to others.
Tertiary stage (late stage)
Only small amount of infected develop tertiary stage. Devastating symptoms: syphilitic heart disease, insanity, weakened blood vessels. Occurs 5−40 years after 1st infection.
Syphilis in pregnant females
Infected pregnant women with can infect foetus (by placenta). Once bacteria enters foetal circulation, it damages heart & nervous system.
Diagnosis of syphilis
Syphilis can be cured. Blood tests for antibodies to syphilis.
Treatment of syphilis
Antibiotics during primary stage cure is easy, surgery becomes necessary in later stages.
Genital herpes
Caused by Herpes simplex virus. 2 types, both types transmitted by sexual contact. Symptoms: flu-like, rash.
Healing occurs 1 or 2 weeks. Although healing occurs, virus passes to nervous system for lifetime. Then virus can reinfect (blisters reoccur).
Herpes simplex type 1
Produces ‘cold sores’ sometimes blisters on lips, genitals.
Herpes simplex type 2
Produces blisters on genital area. When blisters break, develops scabs.
Diagnosis of herpes
No cure. Blood test, PCR test, viral culture taking tissue sample of sores.
Treatment of herpes
Drugs reduce pain from blisters.
Genital warts
Caused by human papillomavirus virus (HPV) on genitals. Warts are flat, raised, cauliflower-like growths transmitted by sexual contact with infected.
Diagnosis of warts
No cure. Blood test, biopsy wart sample.
Treatment of warts
Freezing, cauterisation on warts.
HIV (Human immunodeficiency virus)
HIV weakens body’s immune system, so person is susceptible to infection by other micro-organisms and some cancers. HIV infects white blood cells (T-lymphocytes) then duplicates into millions copies.
AIDS
HIV causes AIDS (acquired immune deficiency syndrome). Almost all HIV cases results in AIDS.
Acute infection
1st HIV infection replicating rapidly and HIV levels in blood is high. Symptoms: flu-like. Immune response overcomes infection, patient recovers. Lasts 2-3 weeks.
Chronic infection
Asymptomatic (no symptoms). Virus continues multiplying, but low rate. May last 10 years+.
AIDS
Develops when immune system is damaged enough that it cannot protect against other infections. Now, person has high viral load and low levels of white blood cells T-lymphocytes.
HIV transmission
Only by body fluids (blood, seminal fluid, breast milk) from contact with 1 person’s bloodstream or mucous membranes of another. Doesn’t spread by coughing, sneezing because HIV is only in blood.
E.g.,
- Unprotected sex with infected.
- Implements (needles, syringes shared with infected).
- Infected pregnant mother to child.
- Incorrect blood transfusions.
Diagnosis of HIV
No cure. Blood test for antibodies to HIV (can’t effectively detect till 2-12 weeks after infection), viral load (virus amount in body).
Treatment of HIV
Combination drug therapies (PEP-Post exposure prophylaxis) prevents, slows replication preventing development, but must be taken forever.
