Most Common

Question 1

Most common cause of septic arthritis

Answer 1

Staphylococcus aureus

[also says that N.gonorrhea is the most common cause of septic arthritis in sexually active adults]

Question 2

Most common cause of osteomyelitis

Answer 2

Staphylococcus aureus

Question 3

Most common cause of endocarditis of artificial heart valves

Answer 3

Staphylococcus epidermidis

Question 4

1 cause of meningitis in neonates

Answer 4

Streptococcus agalactiae (group B strep)

Question 5

1 cause of community-acquired pneumonia

Answer 5

Streptococcus pneumoniae

Question 6

Most common bacterial cause of meningitis, otitis media, pneumonia, and sinusitis

Answer 6

Streptococcus pneumoniae (MOPS mneumonic)

Question 7

Which is more common, Enterococcus faecium or Enterococcus faecalis?

Answer 7

E. faecalis

Question 8

Most common illness associated with Klebsiella pneumoniae infection

Answer 8

UTI (often nosocomial, associated with foley catheter)

[note that UTI is also the most common illness associated with Serratia marcescens]

Question 9

1 cause of osteomyelitis in patients with sickle cell disease

Answer 9

Salmonella typhi

Question 10

1 cause of UTIs

Answer 10

Escherichia coli

Question 11

1 cause of gram-negative nosocomial pneumonia

Answer 11

Pseudomonas aeruginosa

Question 12

Leading cause of blindness worldwide

Answer 12

Chlamydia trachomatis (group A-C)

Question 13

Most common bacterial STI

Answer 13

Chlamydia trachomatis (group D-K)

Question 14

Most common cause of erysipelas

Answer 14

Strep pyogenes

Question 15

Which is more common in the US, Shigella sonnei or Shigella dysenteriae?

Answer 15

Shigella sonnei

Question 16

What is the most common cause of non-bacterial (aseptic) meningitis in the US?

Answer 16

Enteroviruses: (Poliovirus, Coxsackie A and B, and Echovirus) = Picornavirus family

Question 17

Most common opportunistic infection in the U.S. among AIDS patients?

Answer 17

Pneumocystis jiroveci pneumonia (PCP)

Question 18

What is the #1 cause of pneumonia in young children, especially infants <6 months old?

Answer 18

Respiratory syncytial virus (RSV)

Question 19

1 cause of severe diarrhea in in infants < 3 years old?

Answer 19

Rotavirus

Question 20

Most common cause of corneal blindness in the U.S.?

Answer 20

Herpetic keratitis

Question 21

Most common cause of viral encephalitis in the U.S.?

Answer 21

HSV-1

Question 22

What is the most common viral cause of mental retardation?

Answer 22

CMV