Neisseria Flashcards
Characteristics of Neisseria
Gram Negative Diplococci (kidney bean)
LPS Endotoxin Capsulated Pili (Antigenic Variation) Chocolate Agar (enriched media) Oxidase Positive IgA Protease Oxidize glucose
What are the classification differences between N.Gonorrhea and N.Meningitidis?
N.Gonorrhea: No growht on blood agar, no maltose oxidation
N.Meningitidis: Growht on blood agar. Oxidize Maltose
Why is complement deficiency important in Neisseria disease?
Bactericidal activity against Neisseria requires intact complement
C5-C9 complement deficiency -> no MAC complex -> increased susceptibilty to Neisseria
What determines pathogenicity of Neisseria?
Pili
Polysaccharide Capsule: prevents phagocytosis until opsonization
LPS
What is the clinical result of N.Meningitidis infection?
Meningococcemia (sepsis): Shock, hemorrhage, purpura, adrenal hemorrhage
Meningitis: HA, AMS, petechiae
Pneumonia
Arthritis
Pericarditis
Urethritis
What is an immunizing event in N.Meningitidis infection?
REspiratory colonization in nasopharynx area -> make Ab-> gone-> immunized
How do we use lab tools to diagnose N.Meningitidis?
CSF, Blood, Skin Cultures:
Oxidase positive, oxidize glucose and maltose
Nonselective mediat (blood or chocolate)
Growth inc in CO2
How does a blood smear of a pt with meningococcemia look like?
Immature neutrophils with N.meningitidis inside the cell -> phagocytosed
How is N.Meningitidis treated?
Penicillin
Ceftriaxone
What is a prophylactic prevention method for N.Meningitidis?
Rifampin for household contacts
What is the vaccine for N.Meningitidis?
Polysaccharide containing groups other than B conjugated to Diphtheria toxoid
DOES NOT INCLUE GROUP B
What are the new vaccines for N.meningitidis and hwo is it given to?
New serogroup B vaccines to cover group B
Only given to very high risk patients
Who are at increased risk for meningococcal disease?
Children at age 11
College frehsman living in dorms
Asplenic and Sickle Cell Patients
What are the antigenic structures of N.Gonorrhea?
Pili: adherence factor
PorB : outer membrane porin protein
Opa: adherence proteins -> gives opaque appearance to colonies
Rmp: stimulate blocking antibodies
Which antigenic structures of N.Gonorrhea show antigenic variation?
Pili
Opa
How is N.Gonorrhea most commonly transmitted?
STD
What are the reservoir for N.Gonorrhea?
Asymptomatic carrier patients
What causes the innflammatory response and damage in N.Gonorrhea?
LOS and peptidoglycan fragments
How does N.Gonorrhea cause PID
Pelvic Inflammatory Disease
LPS and fragments spread to deeper structures -> endometrial cavity -> fallopian tubes-> PID
How does N.Gonorrhea avoid the immune system?
Antigenic variation Resist Phagocytosis: Opa/Pili Bind Transferrin in host IgA1 protease Evade Ab and complement mediated killing- RMP causes blocking antibodies
What are the most common manifestations in males with N.Gonorrhea?
Urethritis
Purulent Urethral Dishcarge
What is the primary clinical disease for gonorrhea?
Urethritis/Cervicitis
Proctitis
Pharyngitis
Conjunctivitis
What is unique about septic arhtritis with N.Gonorrhea?
Asymmetric: Only 1 knee would swell up with purulent fluid
How is N.Gonorrhea dx in the lab?
Gram Stain
Cultures: Chocolate agar + CO2, Martin Lewis, Oxidase Positive, Oxidize Glucose (NO MALTOSE)
PCR: