Sexually Transmitted Diseases Flashcards
(62 cards)
Symptoms of chlamydia and gonorrhea in men?
Causes urethritis and epididymitis, conjunctivitis and anorectal infection. Gonorrhea can cause pharyngitis. Chlamydia can cause neonatal pneumonia.
What are the 2 most common bacterial STDs?
Gonorrhea and Chlamydia
Symptoms of gonorrhea and chlamydia in women?
Mucopurulent cervicitis, Pelvic inflammatory disease (PID), tubo-ovarian absecess (TOA), peritonitis, dysuria-pyuria syndrome, Fitzhugh-Curtis syndrome, conjunctivitis and anorectal infection. Only gonorrhea can cause pharyngitis, only chlamydia can cause neonatal pneumonia.
What are the sequelae of gonorrhea?
Disseminated gonococcal infection (DGI) and reactive arthritis (Reiter’s syndrome).
Physiology/structure of Neisseria gonorrhoeae?
Gram negative, diplococcus, no capsule.
Virulence factors of Neisseria gonorrhoeae?
Pili- attachment to host cells. Antigenic variation of pili allows for no significant immunity to develop, re-infection can occur.
Por protein- promotes intracellular survival, evades destruction by phagolysosome
Opa protein- mediates binding to epithelial cells
Beta-lactamase enzymes- promote penicillin resistance
Pathogenesis of Neisseria gonorrhoeae?
Organism attaches to mucosal cells via pili and Opa protein, penetrates into the cells. Establishes infection in subepithelial space. Lipooligosaccharide stimulates inflammatory response that releases TNF, cytokines, WBCs cause clinical findings of discharge. Por protein evades destruction.
Epidemiology of gonorrhea?
Humans are only natural host. Transmission is through direct mucosal contact with infected mucous membranes/fluids.
Adolescent case rates 6-7x higher than general population.
90% of males become symptomatic within 5-7days of infection. Less than 50% of females become symptomatic within 2 weeks of infection.
Laboratory diagnosis of gonorrhea?
Diagnosis in men with urethritis when Gram stain of urethral discharge reveals intracellular Gram negative diplococci. Thayer-Martin/special media used to culture N. Gonorrhoeae.
Non-culture diagnostics are gold standard now. PCR or Nucleic Acid Amplification Tests (NAATs).
Combined NAAT assays for GC/CT now available.
Treatment of uncomplicated gonococcal infections?
Intramuscular Ceftriaxone AND oral Azithromycin. Always treat for chlamydial co-infection.
Physiology/structure of Chlamydia trachomatis?
Small Gram negative bacillus. Obligate intracellular bacterium. Different serotypes.
What are the different serotypes of Chlamydia trachomatis?
Serotypes A,B,C: endemic eye disease (trachoma) in developing world
Serotypes D-K: genitourinary STD syndromes (chlamydia infection)
Serovars L1-L3: STD called Lymphogranuloma venereum (LGV)
What are the 2 forms of the Chlamydia trachomatis life cycle?
Elementary body (EB): infectious form Reticulate body (RB): noninfectious intracellular form that promotes replication
What is the pathogenesis of Chlamydia trachomatis?
EB enters cells, replicates, infects other cells, destruction of cells. Leads to inflammatory response including granulocytes, lymphocytes, plasma cells. Receptors for the EB are only found on mucous membranes of urethra, endocervix, endometrium, Fallopian tubes, anorectum, respiratory tract, and conjunctivae.
Sequelae of Chlamydia trachomatis?
No lasting immunity, re-infection is common. Inflammatory response with re-infection is strong and can lead to organ damage– blindness or sterility.
Epidemiology of chlamydia?
Humans are the only natural hosts. Route of transmission is direct mucosal contact with infected mucus membranes or infected fluid. Also congenital (mother has chlamydia when baby born).
Which is the most widespread bacterial STD?
Chlamydia
What is silent Pelvic Inflammatory Disease (PID)?
Asymptomatic chlamydial infection leads to chronic infection, can persist as long as 2 years in female genital tract. Primary reason for tubal infertility. SCREENING IS ESSENTIAL.
Laboratory diagnosis for Chlamydia?
Not cultured in laboratories b/c living tissue/cells necessary for culture. NAATs used for diagnostics. Single swab for GC and CT common.
Benefits and drawbacks of urine-based diagnostics for chlamydia and gonorrhea?
No pelvic exam, no urethral swab, accuracy, enhances screening opportunities, enables data collection on asymptomatic population.
No substitute for sexual history-taking, no detection of resistance, cannot test rectal/oropharyngeal specimens, amplification inhibitors can lead to false negatives.
Treatment of uncomplicated chlamydial infections?
Azithromycin (macrolide) single dose OR Doxycycline (tetracycline) 7 day regimen
Equally efficacious.
What are the signs and symptoms of urethritis in males?
Dysuria, discharge, and burning. Discharge varies in color and amount. Gonorrhea tends to be more purulent but can fool you.
Diagnosis of gonoccocal urethritis?
Made by Gram stain: intracellular Gram negative diplococci.
Confirmed with culture or NAAT. IF no Gram negative diplococci then nongonococcal urethritis (NGU).
How does epididymitis present?
Presents as subacute onset of pain, swelling, and erythema of the scrotal sac, usually unilaterally. Moderate to severe tenderness along with swelling and erythema on exam. Concurrent urethral discharge may be present. Almost always caused by gonorrhea or chlamydia.
