581. How many percent of infective endocarditis is due to staphylococci aureus infection?
A. <10%
B. 20-30%
C. 30-40%
D. 40-50%
E. >50%

582. Complications of staphylococci aureus infective endocarditis include:
A. Focal GN
B. Diffuse GN
C. Septic emboli
D. Suppurative pericarditis
E. All of tbe above

583. Streptococci is NOT:
A. Facultative anaerobes.
B. Most are beta-hemolytic
C. Anti-streptococci M protein antibodies may cross react with host cardiac myosin.
D. Characterized by tbe tendency to form local destructiveness & abscesses.
E. Bind host Ig FcR & degrade C5a.

584. Which of the following pairing of Clostridium & its toxin is FALSE?
A. Clostridium Perfringens – alpha toxin
B. Clostridium Botulinum – botulinum toxin
C. Clostridium Difficle – Theta toxin
D. Clostridium Tetani – Tetanospasmin
E. None of the above

585. Which of the following statements regarding Clostridium is FALSE?
A. Tetanospasmin from clostridium tetani travels up the peripheral nerve to block neurotransmitter release from the inhibitory nerves.
B. Botulium toxin is secreted by Clostridium botulinum.
C. Toxin A from clostridium difficle is a potent enterotoxin & chemoattractant
D. 50% clostridium perfringens infection follow trauma
E. Botulinum toxin blocks ACh release, leading to descending paralysis from central to extremities.

586. Which of the following statements about bacterial toxin production is TRUE?
A. Endotoxins are produced by gram +ve bacteria
B. All biologic activities of lipopolysaccarides are mediated by induction of host cytolcines
C. Lipopolysaccharides are part of the outer wall of gram +ve bacteria
D. Bacteria secrete a variety of enzymes including lipopolysaccharide
E. Diphtheria toxin is a typical endotoxin

587. Infection with Clostridium perfringens typically causes which of the following?
A. Suppurative inflammation
B. Granulomatous inflammation
C. Cytopathic inflammation
D. Necrotising inflammation
E. Chronic inflammatiou

588. Which of the following statemeuts about mycobacteria is FALSE?
A. Mycobacteria are aerobic non-spore forming bacteria
B. Mycobacterium tuberculosis has no endotoxins or exotoxins
C. Ghon complexes are residual from primary infection
D. Caseous necrosis is characteristic
E. Mantoux testing is an example of Type III immune complex reaction

589. Chlamydia produce all of the following EXCEPT:
A. Pelvic Inflammatory Disease
B. Acute epididymitis
C. Reiter’s Syndrome
D. Condylomata lata
E. Lymphogranuloma venereum

590. In hepatitis:
A. Hepatitis B is an RNA -containing virus
B. The carrier state for HepB is defined as the presence of HBsAg in serum for 6 months or longer
C. Elevated IgM anti-HBc indicates recent acute infection
D. Anti-Hbe appears after HBeAg disappears implying chronic infection
E. Hepatitis D requires co-infection with hepatitis C to cause infection