Bacteriology

Neisseria gonorrhoeae Gram negative, diplococci Fastidious growth requirements – 35 oC, humid, O2 and CO2 rich Oxidase and catalase positive, acid producing by oxidation of glucose Outer surface is antigen rich 1) proteins – pili (initial attachment), Por (prevent phago-lysozome fusion), Opa (mediates attachment to eukaryotic cells), Rmp (protects antigens from antibiotics) 2) protein receptors for: transferrin, lactoferrin, hemoglobin  acquire iron 3) lipooligosaccharide – endotoxin 4) immunoglobulin protease – destroys IgA 5) B-lactamase – hydrolyzes B-lactam ring in penicillin Pathogenesis/Immuni Strictly a human pathogen ty Attach and penetrate mucosal cells, passing through to subepithelial space Pili, Por and Opa facilitate penetration LOS stimulates release of cytokine (TNF-a) which causes most associated symptoms Epidemiology Humans are the only hosts Women carriers can be asymptomatic but are more at risk to acquire disease  Transmission is mainly sexual (2 nd top STD) Most common in blacks, age 15-24, southeastern U.S., promiscuous individuals Patients with complement deficiency  disseminated infection Clinical Disease Gonorrhea – purulent discharge from involved site (cervix, urethra, anus…) Spreading of infection – through blood to skin or joints, rash and/or arthritis Ophthalmia neonatorum – eye infection acquired by infant at birth Lab Diagnosis Gram stain in symptomatic males only Culturing is sensitive/specific  replaced by nucleic acid amplification assay  Treatment, Ceftriaxone Prevention, Control If patient has Chlamydia too, use doxycycline or azithromycin as well Neonates get silver nitrate prophylactically No vaccines available Education on safe-sex practices needed and follow up with all sexual partners Physiology/Structure