Neisseria

1. Neisseria Filename: Neisseri.ppt

2. Organisms • Neisseria meningitidis: meninges (base of the brain) • Neisseria gonorrhoeae: primary infection sex organs • Branhamella, formerly Neisseria catarrhalis, cocci • Moraxella: coccobacilli • Kingella: coccobacilli • Acinetobacter: coccobacilli

4. N. meningitidis • gram negative cocci, capsules, oxidase positive • Ontario averages 10 cases per year; • 60 in 1994

5. N. meningitidis in CSF

6. N menigitiditis • Excess outer membrane with endotoxin in released into extracellular space of actively growing cells

7. Pathogenesis • colonize the nasopharynx by pili • invasion not prevented by phagocytosis - capsule • toxic effects - lipopolysaccharide endotoxin • bacteria transmitted via the blood - after a mild pharyngitis

8. Meningitis • Infection • chills, fever, malaise, headache • lasts 1-2 days • can be a transient bacteremia with fever • Intracranial pressure • headache, vomiting, fever • rarely papilledema (edema of the optic disk) • possible nuchal rigidity

9. Differential diagnosis: • S. pneumoniae • E. coli • Hemophilius influenzae • N.meningitidis

10. Age Suscepitbilityto Meningiococcus

11. Age differences • Infants • rarely signs of meningeal irritation, • irritability, refuse food, vomiting, no fever • if age less than 2 months, hypothermia • Older children and adults • fever, altered mental states, severe headache, nausea, vomiting and photophobia • acute bacterial meningitis

12. Meningococcal Disease in USA

13. Antigenic determinants: • serogroup: polysaccharide capsule • serotype: outer membrane protein • immunotype: lipopolysaccharide

14. Acute Bacterial Meningitis Neurological signs • convulsion, coma, cervical rigidity, thoracolumbar rigidity, hamstring spasm, exaggerated reflexes • petechiae (minute hemorrhagic spots in the skin) • purpura (hemorrhages into the skin), most common in areas subject to pressure - i.e. axilliary folds, beltline & back

15. Fulminant Meningococcemia Waterhouse-Frederickson Syndrome high mortality sudden onset patient dies within 24 hours no typical signs of meningitis

16. Waterhouse-Frederickson Syndrome Symptoms • high fever, chills and myalgias (muscular pain) • weakness, nausea, vomiting and headache • within a few hours, apprehension, restlessness and delirium • skin lesions • pulmonary insufficiency • overwhelmingly disseminated intravascular coagulation with shock - destruction of the adrenal glands

17. Possible secondary effects from Fulminant Meningococcemia • pneumonia • arthritis • urethritis • petechial skin lesions

18. Gonorrhea

19. Neisseria gonorrhoeae • 1379 cases in Ontario 1994 • 6 cases Windsor-Essex in same period • adherence by pili to mucosal cells • invasion of cells • capsule: prevents phagocytosis • protein I: major surface antigen • Lipopolysaccharide: endotoxin • IgA Protease: destroys immunoglobulin IgA

20. N. gonorrhoeae Structure

21. N. gonorrhoeae pili • Attaches to host cells by means of pili • Closer attachment of bacteria to host cells is mediated by PII • PII is a membrane protein which mediates microcolony formation • PI is an outer membrane porin that may form pores in host cell membranes • PI could impair the ability of phagocytes to kill the bacteria • The main pilin subunit is controlled by a two component regulatory system • Pil A and Pil B

23. Gonorrhea in USA

24. Incidence of Gonorrhea by Gender in USA

26. Incidence of B lactamase producing N gonorrhaeae in USA • Beta lactamase: hydrolyzes the Beta-lactam ring in penicillin

28. Salpinitis

33. Gonorrhea: Males • Men: urethra, purulent discharge, dysuria 2-7 days after infection (incubation period). Complications: epidydimitis, prostatitis, periurethral abscesses

34. Gonorrhea: Females • Women: frequently asymptomatic. When symptomatic: cervix, vaginal discharge, dysuria, abdominal pain, Ascending genital infection, salpingitis, tubo-ovarian abscess, pelvic inflammatory disease (PID)

35. Disseminated infections • Septicemia, infections of skin and joints in 1-3 % of women • more common in women due to untreated symptomatic infections

36. Clinical: • fever, migratory arthralgias, suppurative arthritis in the wrists, knees and ankles, pustular rash on the extremities • Ophthalmia neonatorum - purulent conjunctivitis, acquired at delivery

37. Lab Diagnosis • gram stain • culture

38. Gm Stain N. gonorrhoeae • Urethral discharge

39. Treatment: • penicillin • resistant strains • plasmid encoded resistance

40. The End

41. N. gonorrhoeae pili ...cont. • The gene il E exhibits phase variation from Pil+ to Pil- • In addition there are 106 variations in the antigens on the surface • There are many reasons why a vaccine cannot be effective • Although there are many highly conserved gene sequences but more variable regions than the average for bacteria.

42. Epidemiology of ??? • Disease/bacterial factors • Transmission • Who is at risk • Geography/ season • Incidence • Modes of control

43. Short Answers • Construct a table of the virulence factors associated with ??? and the biological activity of each • Use a series of no more than four diagrams to describe the mechanism of ??? activity • Describe the clinical manifestions ??? • Construct a table listing the common ??? species and the associated human diseases.

44. Neisseria gonorrhoeae structure X protein I cell wall structure Y