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Case Study Pathogenic Bacteriology 2009 Case #2 Jae Kim Roubina Tatarosian James Muro. Case #2 Summary. Age: 15 years old male 24-hour history of dysuria “Pus- like”drainage in his underwear
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Case Study Pathogenic Bacteriology 2009 Case #2 Jae Kim RoubinaTatarosian James Muro
Case #2 Summary Age: 15 years old male 24-hour history of dysuria “Pus-like”drainage in his underwear Urine appeared clear Urinalysis was positive for leukocyte esterase Mutiple white blood cells were seen on microscopic examination Being sexually active with five or six partners in the past 6 months. Yellow urethral discharge
Key Information Pointing to Diagnosis • Presence of intracellular Gram- cocci(or dp) in white blood cells (PMNs). • Dysuria: Difficulty in urination • “Pus-like” drainage: suppuration and possible indication of infection • Positive leukocyte esterase test: The leukocyte esterase test detects esterase, an enzyme released by white blood cells. The leukocyte esterase test is used to screen for gonorrhea and for amniotic fluid infection. • Yellow urethral discharge: possible indication of urethritis. • Based on the Gram staining and his symptoms, gonococcal infection is suspected.
Diagnosis Gram stain of purulent exudate from the urethra (x1000) shows polymorphonuclear leukocytes containing numerous intracellular Gram negative diplococci.
Diagnosis • Direct Microscopic Examination for Gonococcal Infection • -Demonstration of G- intracellular diplococci, appering as kidney shaped, from a symptomatic male with discharge, correlates at a rate of 95% with culture and is evidence of gonococcalinfection. • -Because women have vaginal commensal flora that resemble gonococci, direct Gram stain correlates in only 50% to 70% of cases with culture. The direct Gram stain may be helpful in a symptomatic woman with discharge (from endocervix), but culture is necessary for confirmation.
Laboratory Diagnosis • fastidious and require serum or blood in addition to other growth factors • Use Chocolate media • Selective media : Modified Thayer Martin is used. • It is chocolate media containing various antibiotics to inhibit the growth of G+ organisms, fungi, and swarming Proteus • Require a CO₂ concentration of 3-10% for growth. • Carbohydrate Utilization Test: • N.gonorrhoeae use only glucose • Nucleic Acid Assay: detects gonococcal antigen directly from cervix and urine.
Diagnosis Small translucent to grayish-white colonies Modified Thayer Martin
Neisseriagonorrhoeae Virulence factors -Pili: Attachment to human columnar epithelial cells, inhibit phagocytosis. - Protein I: Outer membrane protein that function as porin to allow small molecules to pass through membrane. Critical for intracellular survival and is protective against host’s inflmmatory responses. -Protein II: Outer membrane protein, attaches to PMNs and induces the endocytic uptake of GC. -Protein III: Blocks host’s IgG activity against the organism by forming blocking antibodies.
Neisseriagonorrhoeae • Virulence Factors • LOS (lipooligosaccharide) • -Undergo antigenic variation • -Adherence and invasion • -Molecular mimicry of host structure • -Inhibit PMN activation • Capsule: prevent phagocytosis • IgA1 protease: cleaves IgA (found in mucosal membranes) for mucosal attachment • Iron capturing ability from the host: plays a role in disseminated gonococcal infection.
Neisseriagonorrhoeae • Disease • Gonorrhea: Sexually transmitted • Males • -Dysuria, urethral discharge,urethritis, prostitis • -Co-infection with Chlamydia trachomatis • Asymptomatic infection in males: 10% • Incubation period: 1-4 days • Females • -Increased vaginal discharge, menstrual irregularity, • frequency of urination, abdominal pain • Asymptomatic infection in females: 20-75% • Asymptomatic individuals are carriers and can transmit the disease to others. • -Co-infection with Chlamydia trachomatis • Pelvic Inflmmatory Disease • -occurs in 10-20% of infected women • -can result in ectopic pregnancy and infertility
Neisseriagonorrhoeae • Disseminated gonococcal infection • -can result in endocarditis, maculopapular rash, arthritis, and meningitis • Gonococcalophthalmianeonatorum • - can lead to blindness in newborns • Pharyngitis • Rectal infection
Neisseriagonorrhoeae • Treatment • For penicillin resistant strains, use spectinomycin (or ceftriaxone) and 7 days of doxycycline to treat possible coexisting C.trachomatis infection. • Amoxicillin or ampicillin plus probenecid can be used for uncomplicated cases such as acute urethritis, rectal infection, vaginal discharge, gonococcalophthalmianeonatorum. • Gonococcalophthalmianeonatorum: erythromycin eye drops are given at birth to prevent the infection. • Finish the entire course of antibiotics and check for possible reinfection from N.gonorrhoeae or C.trachomatis
Neisseriagonorrhoeae • Until 1976, almost all strains were susceptible to penicillin. • Resistant strains are emerging and β-lactamase testing is necessary. • Accroding to the CDC, approximately 700,000 new gonorrheal infections occur yearly in the U.S., and only about half of the cases are reported. More than 5% of people between ages of 18 and 35 are asymptomatic individuals. • New strains are emerging with higher resistance to antibiotics.
Neisseriagonorrhoeae • Prevention • -Protected sex • -Consider regular gonorrhea screening if you ever had the infection. • -Sexual partners should be tested • Vaccine • - No reliable vaccine against Neisseriagonorrhoeae since gonococci have ingenious methods of eluding the host’s immune system. Pili and protein II are subject to antigenic variation. • - Primary target in developing an effective vaccine is to block the first step in infection which is the attachment to host’s urogenital cells via pili.
Neisseriagonorrhoeae • Cherpes TL, et al, 2006, The Association Between Pelvic Inflammatory Disease, TrichomonasvaginalisInfection, and Positive Herpes Simplex Virus Type 2 Serology, Sexually Transmitted Diseases, VOL 33: Pg 747-752. • Pelvic inflammatory disease is a condition in which there is infection on the reproductive tract of women. • This has been associated with an ascending cervical infection caused by the vaginal discharge pathogens of Neisseriagonorrhoeaeand Chlamydia trachomatisand by the anaerobic bacteria associated with bacterial vaginosis. • Objective: Association between PID (N.gonorrhoeae), T.vaginalis infection and Herpes Simplex Virus Type 2.
Neisseriagonorrhoeae • Materials and Methods: • - 736 women, cross-sectional investigation of the association between lower genital tract bacterial infections and PID. • -Nonpregnant women between 15 and 30 years of age with purulent cervical discharge, untreated N.gonorrhoeae or C.trachomatis infection, symptomatic, bacterial vaginosis, or sexual contact with a male diagnosed with gonorrheal,chlamydial or nongonococcalurethritis were eligible to participate. • -Women with a history of symptomatic PID were not participated. • -Vaginal discharge was used for Gram stain diagnosis of bacterial vaginosis and T.vaginalis culture. • -Endocervical specimens for N.gonorrhoeal culture and C. trachomatispolymerase chain reaction. • -Endometrial biopsy
Neisseriagonorrhoeae • Results: • -Compared the prevalence of the pathogens in patients with and without HSV-Type 2 who presented with vaginal discharge with or without clinical PID. • -Increased risk of PID with N. gonorrhoeae • -Showed that women with HSV-Type 2 infection and lower genital tract infection with N.gonorroeae are highly associated with an increased risk of PID. • -Women coinfected with HSV-2 and C.trachomatis, N.gonorrhoeae, T. vaginaliswere more likely to be diagnosed with PID than the women with HSV-2 alone. • -C. trachomatisandN.gonorrhoeaeare highly associated in causing PID.
Take Home Message • N.gonorrhoeae causes mainly cause gonorrhea. • Symtoms include dysuria, urethral discharge, abdominal pain, sore throat, vaginal discharge, uterine tenderness. • Diagnose by microscopic examination and nucleic acid assay • Treatment by combination of antibiotics to treat possible coinfection with C.trichomatis. • Follow-up visit after finishing the entire course of antibiotics to confirm that no more N.gonorrhoeae and/or C.trachomatisare present. • Safe, protected sex is the best way to prevent this disease since N.gonorrhoeaeis transmitted by sexual contact. • Vaccines are not available. • New strains that are highly resistant to antibiotics are emerging so prevention is the key to protect oneself from the disease
Reference Cherpes TL, et al. “ The Association Between Pelvic Inflammatory Disease, Trichomonasvaginalis Infection, and Positive Herpes Simplex Virus Type 2 Serology.” Sexually Transmitted Diseases.33.12(2006):747-52. Mahon,Connie,Donald Lehman, and George Manuselis. Textbook of Diagnostic Microbiology. 3rd. St.Louis:Sanders, 2007.