Chapter 20 Learning Objectives PDF

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Professor: Bronwyn Duos...

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Chapter 20 Learning Objectives Overview of the Urinary and Reproductive Systems 1. Name and describe the parts of the urinary system and discuss features that limit infection in this system. • Two human urinary system consists of: o Two kidneys, two ureters, bladder, and urethra • Kidneys o Produce at least 500 ml of urine each day. Filter metabolic waste products out of blood. Regulate water and electrolyte balance. Help manage blood pressure and blood pH. Contain >1,000,000 microscopic nephrons  Functional units that secrete waste products into urine • Ureters o Funnels urine from the kidneys into the bladder • Bladder o Stretches to hold up to 400 ml of urine. o Stretching action triggers the nervous system to stimulate an urge to urinate. • Urine flows from the bladder to the exterior of the body through the urethra • Urogenital infections o Infections and disorders that may jointly affect the urinary and reproductive systems • Sexually Transmitted Infections (STIs) o Described as urogenital infections. Include diverse agents that can be transmitted by sexual contact. 2. Compare and contrast the anatomical differences between the male and female urinary system and the implications these differences may have. • Female urethra: Short and straight • Male urethra: Longer and curved. Passes through the prostate gland. Transports semen out of the penis during an ejaculation. • Due to anatomical differences there are some differences in urinary system infection risks and progression in men vs. women: o UTIs are more prevalent in women. Urethra is closer to the anus. o Men: Benign prostatic hypertrophy and prostatitis can constrict the urethra; increases risk of UTI. 3. Discuss the features of the urinary microbiome. Urinary microbiome: Diverse. Varies significantly based on many factors (e.g., age, sex general patient health). Differ based on part of the urinary system being considered. Lactobacillus and Streptococcus are the most common genera in the healthy urinary tract

Urinary tract harbors a highly diverse microbiome: – Prevotella, Gardnerella, Peptoniphilus, Dialister, Finegoldia, Anaerococcus, Allisonella, Staphylococcus, Sneathia, Veillonella, Corynebacterium, Ureaplasma, Mycoplasma, Atopobium, Aerococcus, Gemella, and Enterococcus 3. Discuss the structural and functional features of the male and female reproductive systems and describe features that help limit infection. Female reproductive system – Ovaries: Organs that make eggs. Release hormones (e.g., estrogen, progesterone) – Ovulation: Release of an egg from an ovary – Fallopian Tube: Transports egg from ovary to the uterus. Site of fertilization if sperm is present. – Uterus (womb): Muscular, inverted-pear-shaped organ. Houses fetus during pregnancy. Contracts to expel baby during labor. – Endometrium: Superficial layer of tissue that lines the uterus. Shred w/ each menstrual cycle. During pregnancy this layer is not shred by menstruation and is the site of implantation. – Placenta: Made of certain embryonic and uterine cells. Interface b/t maternal and fetal circulation. Releases hormones that support pregnancy. – Umbilical Cord: Links the baby to the placenta. Allows the baby’s blood supply to enter the placenta. – Cervix: Opening to the uterus that leads into the vagina. Site that is swabbed during a Pap smear. Undergoes effacement during labor. – During labor (parturition): Uterus contracts. Pushes the baby through the cervix towards the vagina. – Vagina: Tube-like structure that extends from the cervix to the exterior of the body. Site of standard intercourse. Serves as exit site for menstrual fluids. – Vulva: Surrounds the opening of the vagina. A woman’s external genitalia. o Consists of:  Labia minora: lips that enfold the vagina and urethra  Clitoris: erectile tissue  Labia majora: lip folds that enclose the female external genitalia Male reproductive system – Structures needed to male semen and convey it out of the penis during ejaculation – Scrotum: Pouch of skins that contains two testicles. – Testicles: Organs that make sperm cells. Produce a variety of hormones. – Epididymis: Store sperm until ejaculation. – Vas deferens: Transport sperm from epididymis to prostate. – Semen: Liquid containing sperm. Contains fluids added by the sex glands. Travels through the urethra down the penis during ejaculation.

4. Outline what is meant by TORCH agents and discuss their implications in pregnancy. – Placenta is a selective barrier that protects the developing fetus but it’s not a universal barrier – A number of pathogens can cross the placenta and affect the fetus – Serious complications may develop o Stillborn baby, congenital defects, spontaneous abortion – “TORCH”: pathogens that can be vertically transmitted to a developing fetus – Toxoplasma gondii Other infections Rubella virus Cytomegalovirus Herpes simplex viruses – HIV, syphilis, parvovirus B19, listeriosis, varicella-zoster virus, coxsackievirus, enteroviruses, and Zika virus 5. Discuss the roles normal reproductive system microbiota have in both sexes. Vaginal microbiome in reproductive-age women – Dominated by the Lactobacillus genus • L. iners, L. crispatus, L. gasseri, and L. jensenii are most prevalent – Lactobacillus species produce lactic acid • Lowers vaginal pH to 3.5–4.5. Limits certain microbial growth. – Vaginal lactobacilli produce bacteriocins. Limit growth of competing bacteria. Antibiotic therapies can trigger dysbiosis – Increase of vaginal pH. May allow for opportunistic infection. Candida albicans. • Pre-term labor – Labor onset before 37 weeks of gestation – At least 40% of pre-term deliveries are associated with an intrauterine infection – May be caused by:  Decreased Lactobacillus levels and increases in Gardnerella and/or Ureaplasma  Increase of Burkholderia species

Urinary System Infections 7. Differentiate complicated from uncomplicated urinary tract infections. Generalities associated w/ UTIs: usually caused by bacteria given the proximity of the urethra to the anus and genitalia. Can be introduced by medical interventions (catheters). Uncomplicated UTIs – Occur in otherwise healthy people with a normally structured urinary tract – Readily resolve with drug therapies Complicated UTIs – Develop in people who are catheterized – Patients usually have urinary tract malformations and/or underlying health conditions

8. Define the terms urethritis, cystitis, ureteritis, and pyelonephritis. Lower UTIs • Urethritis: Inflammation of the urethra • Cystitis: Inflammation of the bladder Lower UTIs can progress to upper UTIs • Ureteritis: Inflammation of the ureters • Pyelonephritis: Inflammation of one both kidneys o Can leave scar tissue in the kidneys. Impairs kidneys functions. May lead to renal failure.  Dialysis or kidney transplant may be the only treatment to keep a patient alive. 9. Describe the signs, symptoms, risk factors, and potential long-term impacts of lower and upper UTIs and describe how UTIs are diagnosed. – Despite the diverse agents that cause UTIs, they all tend to induce similar symptoms. – Lower UTIs cause: Dysuria, pyuria and/or hematuria may also develop. Cloudy, smelly urine. Lower abdominal pain. – Upper UTIs cause: Fever, nausea, and vomiting. Severe abdominal and lower back pain near the waistline (flank pain) – Most common method for detecting UTIs is using clean catch urine sample in a urine dipstick test. o Indirectly assesses WBC levels by checking for an enzyme called leukocyte esterase. High esterase activity = High WBC levels o Assesses nitrite levels. Certain bacteria reduce nitrate to nitrite. Elevated urine nitrite level = UTI indicator – Positive dipstick results may lead to urine culturing to identify the causative agent 10. Explain the infection-related challenges associated with urinary catheters and the significance of CAUTIs. Catheter-associated urinary tract infections (CAUTIs) – Account for ~1 million cases of complicated UTIs each year. Most common type of healthcare-acquired infection. Most common cause of secondary bacteremia. Urinary catheters – Drains urine from the bladder into a bag. Greatly increase the risk for UTIs. Cause 70–80% of complicated UTIs. 11. Summarize the features of causative agents of UTIs, with particular emphasis on uropathogenic Escherichia coli and Staphylococcus saprophyticus. Enteric bacteria – Bacteria normally found in the intestinal tract. Cause the vast majority of UTIs. Uropathogenic Escherichia coli (UPEC) – Flagellated, Gram-negative rods. May become filamentous during infection.

– Characteristics: 70-95% of uncomplicated UTIs. 50-65% of complicated UTIs. – Mechanism of disease o Possess diverse virulence mechanisms. Adhesion (e.g., pili, adhesins) o May invade bladder epithelial cells and take on an intracellular lifestyle o Inside host cells, UPEC release: Siderophores, Proteases, Toxins – Complications: Bacteria may infect kidneys. Kidneys contain numerous capillaries that bacteria can invade. Allows for the infection to spread into the bloodstream. – Other enteric bacteria that cause UTIs include: o Proteus mirabilis, P. aeruginosa, Klebsiella pneumoniae – Most common Gram-positive bacteria isolated in uncomplicated UTIs: o S. saprophyticus, Enterococcus faecalis, Group B Streptococcus (GBS), S. aureus 12. Describe the clinical and epidemiological features of leptospirosis. Leptospirosis – Etiological agent: Leptospira interrogans. Gram-negative spirochetes. – Transmission: Ingesting bacteria in animal excrement (e.g., rodents, livestock, dogs). Enter the body through: skin abrasion and across mucous membranes. In the body, the bacteria make their way through the bloodstream to the kidneys. – Signs and symptoms: Fever, headache, vomiting. May progress to renal failure, liver failure, meningitis, or respiratory distress.

Reproductive System Viral Infections 13. Describe the clinical and epidemiological features of genital herpes. Genital Herpes • Etiological agent: Herpes simplex virus 2 (HSV-2) • Unprotected oral sex can transmit HSV-1 to the genital area. Oral sex transmit HSV-2 from the genitals to the mouth. Oral HSV-2 infections shed very few virions • Signs and symptoms: Enters epithelial cells. Causes an initial, severe outbreak of ulcers as quickly as three days after transmission. “Dewdrop on a rose petal” lesions. Clear pustule above a reddened base. • Complications: Causes persistent latent infections. Greater risk for HIV. • Treatment: No cure. Acyclovir can shorten outbreaks and suppress flare-ups. 14. Compare and contrast HSV-1 and HSV-2. HSV-1: Main cause of oral herpes lesions and not transmitted sexually. HSV-2: Sexually transmitted disease 15. Detail the consequences of neonatal herpes. Neonatal Herpes • Etiological agent: HSV-2 • Transmission: 90% of cases develop when HSV-2 is transmitted during delivery. 10% of cases develop when HSV-2 is transmitted across the placenta.

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Three major clinical presentations: o Skin, eye, and mouth (SEM) manifestations  Mildest and most common (occurs in ~45% of cases) o Central nervous system (CNS) effects. 30% of cases progress to CNS. o Disseminated infections: Most dangerous form. Occur in ~25% of cases.

Complications: Disseminated infections can lead to: Long-term neurological problems. Death in 1 of 4 infected infants. • Treatment: Antiviral drugs o Helps prevent HSV-2 from spreading to the CNS or progressing to DI • Prevention: C-section can reduce the risk of neonatal herpes. 16. Explain the clinical and epidemiological features of human papilloma viruses (HPVs). Human papilloma virus (HPVs) • Characteristics: Most common STI in the world. HPVs are so common that almost every sexually active person will be infected w/ some type of HPV in their lifetime. • Signs and symptoms: Most infections are asymptomatic. Type 6 and 11 are best known for causing genital warts. Type 16 and 18 are cancer causing. HPV causes 90% of cervical cancers. • Complications: Increased risk for cancer. • Treatment: Self-resolving infection w/in 2 years for 9 out of 10 patients. • Prevention: HPV vaccine. Pap smear screening. 17. Describe the Pap smear method and its clinical applications in preventive care. • Pap smear screening detects HPV infections by analyzing precancerous and cancerous cervical cells. • Cervical cancer has a 93% survival rate after 5 years if detected early w/ a PS. •

Reproductive System Bacterial Infections 18. Explain the differences between vaginitis and vaginosis. Vaginosis – An overgrowth of one type of microbe over another in the vagina – Symptoms may include foul-smelling vaginal secretions &/or excessive secretions Vaginitis – Vaginal inflammation – May be caused by infection or adverse reactions to chemicals (e.g., spermicide) 19. Describe the clinical features of vaginosis and explain how it can be diagnosed and treated. Bacterial Vaginosis: • Etiological agent: o Decrease in the normal level of Lactobacillus species in the vagina o Polymicrobial infection  Gardnerella vaginalis, Bacteroides spp., Mobiluncus spp., Ureaplasma urealyticum, and Mycoplasma hominis

o Most women will experience vaginosis at least once in their lifetime • Diagnosis: o Amsel’s criteria (must have 3 of the 4)  Greyish-white vaginal discharge. Vaginal pH above 4.5. Presence of “clue cells”. A positive whiff test. o Nugent’s criteria  Gram staining of vaginal secretion samples.  Abundant cocci and Gram-negative rods.  Presence of clue cells 20. Describe the clinical and epidemiological features of chlamydia, including potential complications in neonates and in untreated women. Chlamydia trachomatis • Gram-negative bacteria. Lives inside eukaryotic cells. Subdivided into two major biovars: o Trachoma  Some serovars target the eyes.  Serovars D-K cause urogenital infections. o Lymphogranuloma venerum • Signs and symptoms: ~50% of men and 75% of women are asymptomatic. In men: nongonococcal urethritis, dysuria, burning and itching of the penis, testicular swelling or pain, and discharge. In women: bleeding/spotting, dysuria, vaginal discharge w/ an odor, vaginal itching or burning, painful sexual intercourse, and pelvic w/ fever • Complications: Asymptomatic cases may go undetected & can lead to complications. In men: chronic epididymitis and infertility. In women: PID and perinatal exposure. • Treatment: Relatively easy to cure w/ antibiotics 21. Summarize the life cycle of Chlamydia trachomatis. 1.) Infection: Elementary body from of C. trachomatis infects host cells. 2.) Elementary body converts to a reticulate body. 3.) Replication: Reticulate body replicates inside cells. 4.) Reticulate bodies convert back to elementary bodies. 5.) Lysis: Elementary bodies lyse out of house cell. • Elementary body is infectious but dormant. 22. Describe the clinical and epidemiological features lymphogranuloma venereum. Lymphogranuloma venerum • Etiological agent: Biovar of Chlamydia trachomatis • Sexually transmitted. Most common in men who have sex w/ men. • Progression: The infection progresses through 3 stages: o Stage 1- small painless lesion develops w/in the urethra, vagina, cervix, anus or on the external genitalia. In men: prostatitis. In women: cervicitis.

o Stage 2- bacteria enter lymphatic vessels and travel to inguinal lymph nodes  Patient develop fever, buboes and possibly necrosis o Stage 3- progressive edema & fibrosis leads to severe destruction of the genitalia. • Treatment: Cured w/ antibiotics 23. Describe the clinical and epidemiological features of gonorrhea infection, including potential complications in untreated women and neonates. Gonorrhea • Etiological agent: Neisseria gonorrhoeae. Gram-negative. Intracellular diplococcus. • Transmission: Sexually transmitted. • Signs and symptoms: Most infections are asymptomatic. Men may develop dysuria discharge from the penis, epididymitis, and prostatitis. Women may develop painful urination, increased vaginal discharge, and bleeding/spotting. • Complications: PID and infertility • Diagnosis: Indistinguishable from chlamydia based solely on signs and symptoms. People can repeatedly get chlamydia and/or gonorrhea (or any bacterial STI) so all of a patient’s sexual partners must be treated. • Treatment: The CDC recommends a combination of azithromycin and ceftriaxone. • Neonatal exposure to gonorrhea can result in arthritis, blindness, and meningits. Prophylactic erythromycin eye drops has dramatically decreased blindness due to neonatal gonococcus infection. 24. Describe the clinical features of pelvic inflammatory disease. Pelvic inflammatory disease (PID) Untreated bacterial infections of the female reproductive system may advance to PID • Etiological agent(s) o Chlamydia and gonorrhea are the main causes of PID. Mycoplasma genitalium. Anaerobic bacteria associated w/ vaginosis. • Signs and Symptoms: Salpingitis. Abscesses in the fallopian tubes or ovaries. • Complications: Chronic pelvic pain, ectopic pregnancy, miscarriages and infertility in untreated cases • Diagnosis: Tenderness during a pelvic exam. Blood work. Biopsy, ultrasound, MRI, or laparoscopy. • Treatment: Antibiotic therapy 25. Name the agent that causes syphilis and describe the clinical features of each infection stage as well as the consequences of congenital syphilis. Syphilis • Etiological agent: Treponema pallidum. Gram-negative spirochete. Very few surface antigens that stimulate an immune response. • Characteristics: Reinfection may occur. • The infection starts w/ contact w/ an infected person’s chancres (sores)

Untreated disease progresses in 3 phases: o Primary Stage: Chancre at infection site. Invade the CNS. Subsides in 4-6 weeks. Immune system doesn’t usually kill all the bacteria. o Secondary Stage: Occurs ~3 months after initial infection. Usually involves a rash. Condylomata lata in a subset of patients. Swollen lymph nodes, sore throat, patchy hair loss, fever, muscle aches, or malaise may also occur. Symptoms usually disappear w/in 3 months. Bacteria enters a latent period that lasts for months to years. o Tertiary Syphilis: Causes lesions on the skin and bones, heart damage, and neurological symptoms. Insomnia, vertigo, and seizures can be observed 5 to 10 years after infection. Partial paralysis, loss of sensation, memory impairment, and hallucinations can occur decades after infection. Fatal. • Treatment: Antibiotics (penicillin). A patient’s sexual partners must be treated. Congenital Syphilis • Transmission: Mother-to-fetus during pregnancy • Signs and symptoms: o 2-10 weeks after birth: Skin lesions and nasal discharge w/ blood. o Up to two years later:  Nasal, tooth, or palate deformation. Blindness/deafness may develop • Fetal death, birth defects, or injected infants may result in untreated mothers. • Treatment: Antibiotic treatment of the mother can prevent fetal infection. Bicillin LA injections. 26. Outline the clinical and epidemiological features of chancroid. Chancroid • Etiological agent: Haemophilus ducreyi. Gram-negative nonmotile rods. • Characteristics: Rare in developed countries. One of the most common cofactors for HIV transmission • Signs and symptoms: Painful genital ulcers. Genital lymph node buboes. • Treatment: Antibiotics •

Reproductive System Eukaryotic Infections 22. Identify the signs symptoms, causes, treatments, and consequences of candidiasis. Velvovaginal candidiasis (Yeast Infection) • Etiological agent: Candida albicans. Dimorphic. Opportunistic pathogen. • Characteristics: Most common fungal infection of the reproductive system. Normal resident of the vagina. • Transmission: Dysbiosis due to antimicrobial treatments, hormonal changes, etc. • Signs and symptoms: Vaginal itching, burning, and pain. Cottage cheese discharge. • Progression: Invades and colonizes the urinary tract and reproductive organs. May become disseminated and cause a systemic infection.

Complications: Biofilm formation may lead to increased resistance to antimicrobial treatments. • Treatment: Antifungal suppositories, creams, or pills 23. Describe the clinical significance of structural morphogenesis in Candida albicans. Mechanism of disease – Undergo structural morphogenesis to a hyphal form in response to environmental changes (e.g., increased estrogen, pH shift...