Strep Agalactiae, Enterococcus genus

Question 1

Strep Agalactiae General

Answer 1

• Colonizes Vagina, can also be found in male genital tract or colon
• Asymptomatic carrier women 10-30%
• Can reach 20-40% in pregnancy

Question 2

Strep Agalactiae Morphology

Answer 2

• Gram Positive
• Cocci (short chains)
• Encapsulated (polysaccharide)
• Lancefield B (GBS)

Question 3

Strep Agalactiae Cultivation

Answer 3

• Whitish-greyish colonies
• 0.5-1mm round colonies
• B-hemolytic

Question 4

Strep Agalactiae Virulence factors

Answer 4

• Polysaccharide Capsule
• Pili
• C5a peptidase
• B-hemolysin
• Hyaluronidase

Question 5

Strep Agalactiae Neonatal Diseases

Answer 5

• Early onset: Pneumonia, Sepsis, less frequent meningitis (from birth canal)
• Late onset: Meningitis (#1 causative agent)

Question 6

Strep Agalactiae Adult Diseases

Answer 6

• Pregnant women: UTIs, Amnionitis, Endometritis, Postpartum Sepsis
• Elderly: Skin & soft-tissue infections, Bacteremia, Pneumonia (predesposing to cancer, dm, alcoholism)

Question 7

Strep Agalactiae Microbiological Diagosis

Answer 7

• Bacitracin resistant
• CAMP positive (only one)

Question 8

Strep Agalactiae Treatment

Answer 8

• Penicillin!
• Ampicillin can also be used
• Intrapartum Prophylaxis (35w swab)

Question 9

Enterococci Species

Answer 9

• E. Faecalis (80-90%)
• E. Faecium (5-15%)

Question 10

Enterococci General

Answer 10

• Normal Intestinal flora mostly large intestine (facultative pathogen)
• Lancefield D

Question 11

Enterococci Morphology

Answer 11

• Gram Positive
• Cocci (pairs or short chains)
• Non-encapsulated

Question 12

Enterococci Cultivation

Answer 12

• Facultative anaerobic
• Non fastidious
• Blood agar
• Non-hemolytic (or weak a)
• Bile-esculin media turn Black

Question 13

Enterococci Virulence factors

Answer 13

Biofilm making them nosocomial pathogens

Question 14

Enterococci Diseases

Answer 14

• UTI (catheters)
• Endocarditis, sepsis
• Biliary tree infections
• Intraabdominal / wound infections (peritonitis)

Question 15

Enterococci Treatment

Answer 15

• MDR mostly E. Faecium (nosocomial ESKAPE)
• Amoxicillin/Vancomycin + Gentamycin
• VRE: Linezolid, Tigecycline, Quinopristin-Dalfopristin (only faecium)

Question 16

Enterococci resistance

Answer 16

All naturally Cephalosporin Resistant
- E. Faecium is resistant to all B-lactams
(penicillin, cephalo, clinda, macro, aminogly)