Chapter 23: Urogenital System Infections

Comprehensive practice flashcards reviewing urogenital system anatomy, bacterial urinary tract infections, and reproductive tract infections caused by bacteria, viruses, fungi, and protozoa.

What are the primary functions of the human urinary system?

The urinary system filters blood, excretes wastes, and maintains an appropriate electrolyte and water balance.

Identify the anatomical structures labeled 1, 2, 3, 7, and 8 in the provided diagram of the urinary system.

1: adrenal gland, 2: kidney, 3: ureter, 7: urinary bladder, 8: urethra.

What is the functional unit of the kidney, and what pathway does fluid follow through it?

The nephron is the functional unit of the kidney. Filtrate first enters the glomerulus, proceeds to the proximal convoluted tubule (where it is modified by osmosis and active transport), and eventually enters larger collecting ducts as urine.

How does the anatomical relation of the urethra differ between males and females?

In males, the urethra is shared by both the reproductive and urinary systems, whereas in females, the urinary system is separate from the reproductive system and has a shorter urethra.

What clinical signs and symptoms serve as warning signs of an upper urinary tract or kidney infection?

Lower abdomen or lower back pain accompanied by fever with chills, and nausea or vomiting.

What is the primary pathogen responsible for cystitis, and what anatomical factor makes females more susceptible?

Escherichia coli is the primary pathogen (along with Enterococcus faecalis, Streptococcus agalactiae, Klebsiella pneumoniae, and Staphylococcus saprophyticus); females are more susceptible due to their shorter urethra and close proximity to abundant normal microbiota.

What are the hallmark signs and symptoms of cystitis, and what does the term pyuria denote?

Dysuria (painful urination), hematuria (blood in urine), bladder pain, and pyuria, which refers to the presence of pus in the urine.

What pathogens cause pyelonephritis and glomerulonephritis, and what severe outcomes can arise from infection?

Pathogens include E. coli, Proteus spp., Klebsiella spp., and Streptococcus pyogenes. Severe infections may cause kidney scarring, impaired filtration function, sepsis, and death.

How is Leptospira spp. transmitted to humans, and what are the manifestations of disseminated leptospirosis?

It is transmitted from animals to humans through direct contact with infected urine or body fluids. Disseminated infections can lead to jaundice, pulmonary hemorrhaging, and meningitis.

Which bacterial pathogens are associated with nongonococcal urethritis (NGU)?

Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, and Ureaplasma urealyticum.

What specialized cell is visible at the lower left of this vaginal smear, and what clinical diagnosis does it establish?

It is a clue cell (a squamous epithelial cell encrusted with bacteria), which is characteristic of bacterial vaginosis (BV).

What causes bacterial vaginosis (BV), and what antimicrobial therapies are indicated for treatment?

BV is an opportunistic infection resulting from an imbalance or overgrowth of normal vaginal microbiota (such as Gardnerella vaginalis, Bacteroides spp., and Fusobacterium spp.). It is treated with clindamycin, metronidazole, or tinidazole.

What organism causes gonorrhea, and what serious reproductive complications can occur in women if untreated?

Caused by Neisseria gonorrhoeae; women may develop pelvic inflammatory disease (PID), salpingitis, and face an increased risk of ectopic pregnancy or infertility.

Why is microscopic observation of intracellular gram-negative diplococci sufficient for diagnosing gonorrhea in males but inconclusive in females?

In males, gram-negative diplococci inside and outside leukocytes in urethral discharge confirm gonorrhea; in females, normal vaginal flora can include nonpathogenic Neisseria species, necessitating culture or NAAT confirmation.

Why is Chlamydia trachomatis often referred to as a silent infection, and what risk does it pose to women seeking pregnancy?

Most people who have chlamydia are asymptomatic and unaware of infection; if left untreated, it causes pelvic inflammatory disease and scarring that can make it difficult for a woman to get pregnant.

In public health and STI tracking, how is prevalence differentiated from incidence?

Prevalence is the estimated total number of infections (both new and existing) at a given time, whereas incidence is the estimated number of new infections (diagnosed or undiagnosed).

According to CDC estimates, which STI possesses the highest prevalence in the United States?

Human papillomavirus (HPV), with an estimated prevalence of $42.5\text{ M}$ ($42.5\text{ million}$) cases.

What is the primary lesion of syphilis, what is its duration, and what is the first-line medication?

A painless hard chancre appearing at the inoculation site lasting $2\text{--}6\text{ weeks}$; treated with benzathine penicillin G ($2 \times 10^6\text{ units}$) or doxycycline.

What clinical features distinguish secondary syphilis from tertiary syphilis?

Secondary syphilis presents $2\text{--}6\text{ weeks}$ after the chancre disappears with widespread skin and mucosal lesions, condylomata, hair loss, and fever. Tertiary syphilis occurs up to $20\text{ years}$ later, marked by gummas, cardiovascular damage, and neurosyphilis.

How do the chancres caused by Haemophilus ducreyi (chancroid) differ clinically from those caused by Treponema pallidum (primary syphilis)?

Chancroid lesions are soft, painful chancres with pus discharge and swollen lymph nodes, whereas primary syphilis lesions are typically hard and painless.

What viral agents cause genital herpes, and which antiviral agents are used for treatment?

Herpes simplex virus type 1 or type 2 (HSV-1 or HSV-2); managed with acyclovir, famciclovir, or valacyclovir.

How is neonatal herpes acquired, and what are its potential medical consequences?

Acquired through contact with HSV lesions during birth through the birth canal or transplacentally; it can cause skin, mucous membrane, or eye vesicles, and in disseminated cases, motor impairment or death of the newborn.

What cellular abnormality is demonstrated in the cervical cells on the right, and what infection does it indicate?

Koilocytes exhibiting enlarged nuclei and hyperchromasia (darkly stained nuclei), characteristic of human papillomavirus (HPV) infection.

Which specific high-risk strains of HPV are most commonly associated with cervical cancer, and what vaccines are available?

HPV types 16 and 18 (among others); prevented through vaccination with Gardasil or Cervarix.

What predisposing events lead to vaginal candidiasis, and what morphological structures does Candida albicans produce?

It arises opportunistically following immunosuppression or disruption of normal vaginal microbiota; morphological forms include blastospores (budding cells), chlamydospores (resting spores), and pseudohyphae with germ tubes.

Identify the flagellated protozoan pictured and describe how it disrupts the vaginal ecosystem.

Trichomonas vaginalis; it phagocytoses protective lactobacilli, destabilizing the normal flora and altering the vaginal environment.

What are the common clinical signs of trichomoniasis, and what medications are used to treat it?

Signs include urethritis, vaginal or penile discharge, and erythema or soreness of female genitalia; it is treated with metronidazole or tinidazole.