Chapter 23 - Microbial Diseases of the Urinary and Reproductive Systems

Urinary System

Two kidneys, two ureters, the bladder, and the urethra.

Urinary system prevents infection by

Valves prevent backflow from bladder to kidneys, urine is acidic, and urine mechanically flushes out microbes

Female reproductive organs

Two ovaries, two uterine tubes, uterus, cervix, vagina, external genital organs (vulva)

Male reproductive organs

Two testes, epididymis, ductus deferens, seminal vesicles, prostate gland, penis, scrotum

Normal microbiota of urinary system

Urethra supports colonization by some microorganisms

Seminal vesicles - Proprionibacterium, Corynebacterium, Pseudomonas

Microorganisms in the urethra can move up to infect the bladder and kidneys

Normal microbiota of vagina

Lactobacilli (produce H2O2 and lactic acid; growth promoted by estrogen), streptococci, some gram-negatives and anaerobes, Candida albicans yeast

Urethritis

an inflammation of the urethra

Cystitis

inflammation of the urinary bladder

Ureteritis

inflammation of a ureter

Pyelonephritis

inflammation of the kidney and renal pelvis

Escherichia coli

most common cause of UTI

Cystitis causes

Most commonly E. coli and S. saprophyticus

Cystitis symptoms

Dysuria (difficult or painful urination)

Pyuria (pus in urine)

Cystitis sex differences

More common in women due to shorter urethra and proximity to anus; bacteria enter urethra and bladder due to vaginal intercourse and/or poor hygiene

Cystitis diagnosis

> 100 CFU/ml potential pathogens and +LE test

Cystitis treatment

nitrofurantoin

Pyelonephritis etiology

75% of cases caused by E. coli

Pyelonephritis symptoms

Fever and back of flank pain; often preceded by urethritis, cystitis, ureteritis, or systemic infection; can result in bacteremia; scar tissue in kidneys can be life-threatening

Pyelonephritis diagnosis

> 100,000 CFU/ml potential pathogens and +LE test

Pyelonephritis treatment

Cephalosporin

Leptospirosis

Caused by Leptospira interrogans, transmitted via contact (skin/mucosa) with urine-contaminated water from animals

Leptospirosis symptoms

Headaches, muscular aches, fever, kidney failure (Weil's disease) and pulmonary hemorrhagic fever are possible complications

Leptospirosis diagnosis

Rapid serological test

Leptospirosis treatment

Doxycycline

sexually transmitted infections (STIs)

infections caused by sexual contact with infected people; signs and symptoms are not always apparent; over 30 types of infections; most prevented with condoms

STI Home Test Kits

Collect samples at home and mail to a lab

• Screens for chlamydia, gonorrhea, and trichomoniasis

• Results in 1-2 weeks

• Positive tests receive referrals to clinics

• Test for HIV

• OraQuick: oral test

• Test for urinary tract infections

• Uritest dipstick test

Gonorrhea

Caused by Neisseria gonorrhoeae; attaches to reproductive mucosa via fimbriae and invades inter-epithelial spaces; can cause pharyngeal or anal infections; no adaptive immunity due to antigenic variation and Opa proteins inhibiting TCRs

Gonorrhea symptoms

Men: Painful urination and discharge of pus

Women: Few symptoms but possible complications, such as PID; complications if untreated: endocarditis, meningitis, arthritis

Ophthalmia neonatorum

infant blindness due to a gonorrheal infection of the eyes

Gonorrhea diagnosis

Gram stain, ELISA, Monoclonal antibodies

Gonorrhea treatment

Ceftriaxone, azithromycin (resistant to penicillins and fluoroquinolones)

Nonspecific urethritis (NSU)

Also called nongonococcal urethritis (NGU); any inflammation of the urethra not caused by N. gonorrhoeae; most commonly caused by C. trachomatis, M. genitalium, U. urealyticum

NSU symptoms

Painful urination, watery discharge; can be asymptomatic; PID in women

NSU Diagnosis

NAATs (eg PCR)

NSU Treatment

Azithromycin and doxycycline

Pelvic inflammatory disease (PID)

Inflammation of organs in the female pelvic cavity; usually includes the uterine tubes (salpingitis), ovaries, and endometrium; most often caused by polymicrobial infection (N. gonorrhoeae and C. trachomatis)

PID symptoms and treatment

Symptoms: chronic abdominal pain

Treatment: doxycycline and cefotetan

Salpingitis

-infection of the uterine tubes

-Most serious form of PID

-Scarring can cause infertility or ectopic pregnancy

Syphilis cause

Treponema pallidum - gram-negative spirochete; grows slowly in culture; invades mucosa through parenteral route and enters bloodstream inducing an inflammatory response

Yaws

Some T. pallidum subspecies can invade cuts in skin causing ulcers and lesions; not sexually transmitted

Stages of Syphilis

Primary stage: chancre at site of infection 3 weeks post-exposure; painless and highly infectious for ~2 weeks

Secondary stage: skin and mucosal rashes, especially on palms and soles due to inflammatory response

Latent period: no symptoms

Tertiary stage: gummas on many organs due to cell-mediated immune reactions; cardiovascular syphilis and neurosyphilis

Gummas

Soft rubbery tumors seen in third stage of syphilis

Chancre

A painless ulcer, particularly one developing on the genitals as a result of venereal disease.

Cardiovascular syphilis

Possible symptom of tertiary syphilis; weakens the aorta

Neurosyphilis

Possible symptom of tertiary syphilis; affects CNS and can cause dementia

Congenital syphilis

Infection passed from mother to fetus; causes neurological damage to the fetus

Syphilis diagnosis and treatment

Diagnosis: Microscopic tests (DFA-TP), slide agglutination VDRL test, RPR test, EIA, FTA-ABS

Treatment: Benzathine penicillin

Lymphogranuloma venereum (LGV)

• Caused by C. trachomatis

• Infects the lymphoid tissue • Regional lymph nodes become enlarged and tender

• Discharge of pus and scarring

• Diagnosis with blood test for antibodies to the organism

• Treatment with doxycycline

Chancroid

Caused by Haemophilus ducreyi

Painful ulcers of genitals, swollen groin lymph nodes; aids in HIV transmission

Treated with azithromycin or ceftriaxone

Bacterial vaginosis

Caused by Gardnerella vaginalis (gram-negative pleomorphic rod); results in an increased vaginal pH that allows or promotes growth of the bacteria. Signs/Symptoms: Frothy vaginal discharge with a "fishy" odor; Clue cells

Treatment with metronidazole

Vaginitis

A vaginal infection or irritation

Vaginosis

infection of the vagina, with little or no inflammation

Clue cells

Seen in bacterial vaginosis Vaginal epithelial cells covered w/ bacteria

Genital herpes

a sexually transmitted infection caused by the herpes simplex virus 2 (HSV-2)

Genital Herpes symptoms

Painful vesicles, dysuria; sometimes asymptomatic; heals within 2 weeks; recurrences due to latent virus in nerve cells - reactivated by menstruation, stress. or illness

Genital herpes diagnosis and treatment

Diagnosis: culture or PCR

Treatment: Cannot be cured; suppression with acyclovir, famciclovir, and valacyclovir

Neonatal herpes

Life-threatening disease passed from infected mothers to fetus via placenta or to newborns during childbirth; damages CNS, developmental delays, blindness, hearing loss; survival rate 40%; diagnosis via PCR and fluorescent antibody test; treat with IV acyclovir

Genital warts

Condylomata acuminata; caused by human papillomaviruses; Serotypes 6 and 11 cause visible warts; Serotypes 16 and 18 cause cervical cancer

Genital warts treatment and prevention

Treatment: removal of warts, podofilox, imiquimod

Prevention: Quadrivalent or nine-valent HPV vaccine

Candidiasis

Caused by Candida albicans overgrowth on mucosa of mouth, intestinal tract or genitourinary tract - opportunistic infection caused by antibiotics, diabetes, hormones

Oral candidiasis

Thrush; white patches or plaques on the tongue & other oral mucous membranes

Vulvovaginal candidiasis

A yeast infection of the vagina and tissues at the opening of the vagina (vulva); causes vaginitis

Candidiasis symptoms and treatment

Symptoms: Yeasty, thick, yellow discharge

Treatment: clotrimazole, fluconazole

Trichomoniasis

Caused by Trichomonas vaginalis (normal microbiota) overgrowth when acidity of vagina is disturbed

Trichomoniasis symptoms

irritation, profuse foul, greenish yellow frothy discharge (up to 1/2 of cases are asymptomatic)

Trichomoniasis diagnosis and treatment

Diagnosis: microscopic ID or DNA probe

Treatment: metronidazole