(VI)Gram Positive Cocci (3)*Streptococcus agalactiae (GBS)

Question 1

What organism has a positive hippurate test?

Answer 1

Strep. agalactiae

Question 2

Does S. agalactiae have a capsule?

Answer 2

Yes

Question 3

What test distinguishes Strep. agalactiae from all other Strep species?

Answer 3

(+) CAMP test

Question 4

What is a positive CAMP test?

Answer 4

Increasing zone of hemolysis when plated with Staph. aureus

Question 5

Hemolysis: Strep. agalactiae

Answer 5

β

Question 6

Name 3 different presentations infection with Strep. agalactiae

Answer 6

(1) Neonatal meningitis
(2) Sepsis
(3) Pneumonia

Question 7

When is a mother checked for colonization by Strep. agalactiae?

Answer 7

35 weeks

Question 8

How do neonates get infected with Strep. agalactiae?

Answer 8

Infected during passage through birth canal

Question 9

How do you prevent neonatal infection with Strep. agalactiae?

Answer 9

Give the MOTHER penicillin

Question 10

GBS is the normal flora of the

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Answer 10

GBS is the normal flora of the

vagina and colon. 30% of the woman have it 30% of the time (due to menstral cycle)

“When thinking of group B streptococci, think of group** B** for BABY. About 30% of women carry these bugs vaginally, and a baby can acquire these bacteria during delivery. These organisms cause neonatal (< 3 months of age) meningitis, pneumonia, and sepsis.”
- Clinical microbiology made ridiculously simple

Question 11

Occasional oppotunistic GBS infection is most common in

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Answer 11

Occasional oppotunistic GBS infection is most common in

diabetics, comorbidities (older pts, nosocromial, soft tissue/chronic wounds)

Question 12

Treatment of GBS infection is using (not prophylactic)

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Answer 12

Treatment of GBS infection is using (not prophylactic)

Penicillin + Gentamicin

Question 13

What are the 3 bacteria responsible for most meningitis aquired by babies coming out of the birth canal? (vvvv IMPT!!!)

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Which two bacteria cause meningitis in the antibody-free window in babies (from age 6 months to 2 years)?

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Answer 13

What are the 3 bacteria responsible for most meningitis aquired by babies coming out of the birth canal? (vvvv IMPT!!!)

Listeria Monocytogenes, Escherichia Coli, GBS (agalactiae)

Which two bacteria cause meningitis in the antibody-free window in babies (from age 6 months to 2 years)?

Neisseria Meningitidis, Haemophilus Influenzae

Antibody-free window = period after maternal antibodies passively given to fetus wane and before new antibodies develope

Question 14

What are the clinical presentation of GBS infection in neonates?

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Answer 14

What are the clinical presentation of GBS infection in neonates?

Neonatal sepsis, pneumonia, meningitis

Also can cause post-partum infections in mother. Prevention using prophylatic penicillin!!