Overview Most important encapsulated bacteria and fungi (YES Some Nasty Killers Have Pretty Big Capsules) Yersinia pestis Escherichia coli meningeal strains only Salmonella typhi Streptococcus pneumoniae and Streptococcus pyogenes Neisseria meningitidis Klebsiella pneumoniae Haemophilus influenzae type B (B polysaccharide) Pseudomonas aeruginosa Bordetella pertussis and Bacillus anthracis (contains poly D-glutamate capsule) Cryptococcus neoformans only encapsulated fungal pathogen Physiology Quellung reaction antibodies bind to capsule used to visualize S. pneumoniae H. influenzae N. meningitidis K. pneumoniae Capsules serve as antigen in vaccines H. influenzae type B vaccine meningococcal vaccines S. pneumoniae vaccine (pneumovax) Capsules act as antiphagocytic virulence factors Encapsulated bacteria can generally cause meningitis produce IgA protease undergo transformation take up DNA from their environment Opsonization antibodies bind to capsule to aid phagocytosis by macrophages and neutrophils clearance of these pathogens depends on presence of C3 complement or IgG and a functional spleen
QUESTIONS 1 of 1 1 Previous Next (M1.MC.15.75) A 23-year-old male is involved in a motorcycle accident and is brought to the nearest level 1 trauma center. On arrival, the patient's vitals are T: 37 deg C, HR: 102 bpm, BP: 105/60, RR: 12, SaO2: 100%. A FAST exam is performed during the initial workup which demonstrates significant free fluid in the abdomen (Figure A). An abdominal CT scan is subsequently obtained which demonstrates a grade V splenic laceration (Figure B) and the patient is emergently brought to the operating room where a splenectomy is successfully performed. Following surgery, this patient will be at increased risk of infection with which of the following organisms? QID: 106734 FIGURES: A B Type & Select Correct Answer 1 Legionella 4% (16/364) 2 S. aureus 23% (84/364) 3 Shigella dysenteriae 5% (17/364) 4 K. pneumoniae 65% (237/364) 5 Chlamydia 1% (5/364) M 2 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 4 Review Tested Concept Review Full Topic