Streptococcus and enterococcus

Streptococci

IS gram +, is differentiated by hemolysis of RBC's

Streptococcus pneumoniae and a group of oral streptococci (Streptococcus viridans or viridans streptococci) display what hemolysis

alpha

non suppurative diseases from strep

antibodies are shaped so they stick to other non pathogens this is autoimmune disease, filtering in kidneys goes wrong, leads to renal failure

rhumatic fever is

antibodies from a strep infection 4 weeks ago stick to damaged heart valves, so people with rhumatic fever can never get strep again.

viridians streptococci) strep mutans ( S. mutans) in dental caries secrete dextransucrose

creates glucan which is plaque. leads to tooth decay

two types of syndromes associated with group B strep

early onset first 5 days (24 hours) 50% fatality , 33% meningitis 40% pulmonary...... 2. LATE ONSET, 7 days to 4 months lower fatality, commonly menigitis rarely pulmonary

Distinguised from group D streptococci because they have the ability to grow in high salt concentration

enterococcus

comes from normal flora of intestines and is resistant to antibiotics

enterococcus

epidemiology it si higher incidence in winter in cold dry areats and spread by nasal aerosols

epidemiology of strep

Toxins produced by strep:

erthrogenic: causes scarlet fever rash, produced only by LYSOGENIC strains, (has virus genes)

Group A (antigenic constituation by rebeccalancefield) is supperative and has 4 types they are:

erysipelas, impetigo, sepsis, pharyngitis.

Enterococcus faecalis (formerly called Group D Strep) displays ______ hemolysis?

gamma

hemolysis (streptococci classification method) what is alpha?

greening

this strp is predominant in hospital nurseries

group B, risks to babies mothers must be tested

Toxin 2 produced by strep:

hemolysisns strptolysins, S+O hemolysisn kill WBC

what does gamma look like?

nothing happens

colony morphology : small grayish circular slightly raised non-pigmented colonies...

strep

non suppurative disease from strep (1-4 weeks after getting disease syptoms show up)

streptococcal endocarditis, inflamation of the heart, acute are quick (ulceration of heart), subacute not as quick and involve abnormal valves, due to normal flora in Resp tract, causes progressibe damage, can come from dental work.

is a facultative anaerobeGeneral Characteristics: Fermentative metabolism: Carbohydrates are fermented without the production of gas; Major endproducts are lactic acid, ethanol, acetate

streptococcus

what is gram +, and displayed in chains or pairs? Some strains have hyaluronic acid capsule; Produce hyaluronidase later in growth cycle

streptococcus

Catalase negative: Oxidase negative

strptococci

what does beta hemolysis look like?

transparent around colonies

group B streps are resistant to antibiotics and require a combo for treatment?

true

ARe group A streps sensitive to pennicillin?

yes rgoup a streps are sensitive to penicillin