Neisseria meningitidis: meninges (base of the brain)

Neisseria gonorrhoeae: primary infection sex organs

Branhamella, formerly Neisseria catarrhalis, cocci

Moraxella: coccobacilli

Kingella: coccobacilli

Acinetobacter: coccobacilli

N. meningitidis

gram negative cocci, capsules, oxidase positive

Ontario averages 10 cases per year;

60 in 1994

N. meningitidis in CSF

N menigitiditis

Excess outer membrane with endotoxin in released into extracellular space of actively growing cells

colonize the nasopharynx by pili

invasion not prevented by phagocytosis - capsule

toxic effects - lipopolysaccharide endotoxin

bacteria transmitted via the blood - after a mild pharyngitis

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

Differential diagnosis:

S. pneumoniae
E. coli
Hemophilius influenzae
N.meningitidis

Age Suscepitbilityto Meningiococcus

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

Meningococcal Disease in USA

Antigenic determinants:

serogroup: polysaccharide capsule

serotype: outer membrane protein

immunotype: lipopolysaccharide

Acute Bacterial Meningitis

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

Fulminant Meningococcemia Waterhouse-Frederickson Syndrome

sudden onset

patient dies within 24 hours

no typical signs of meningitis

Waterhouse-Frederickson Syndrome

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

Possible secondary effects from Fulminant Meningococcemia

pneumonia

arthritis

urethritis

petechial skin lesions

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

N. gonorrhoeae Structure

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

Gonorrhea in USA

Incidence of Gonorrhea by Gender in USA

Incidence of B lactamase producing N gonorrhaeae in USA

Beta lactamase: hydrolyzes the Beta-lactam ring in penicillin

Gonorrhea: Males

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

Gonorrhea: Females

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

Disseminated infections

Septicemia, infections of skin and joints in 1-3 % of women

more common in women due to untreated symptomatic infections

fever, migratory arthralgias, suppurative arthritis in the wrists, knees and ankles, pustular rash on the extremities

Ophthalmia neonatorum - purulent conjunctivitis, acquired at delivery

gram stain

culture

Gm Stain N. gonorrhoeae

Urethral discharge

penicillin

resistant strains

plasmid encoded resistance

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.

Epidemiology of ???

Disease/bacterial factors

Transmission

Who is at risk

Geography/ season

Incidence

Modes of control

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.