USMLE STEP 3 BIOSTATS COMPREHENSIVE
EXAMINATION TEST 2026 FULL QUESTIONS
AND CORRECT ANSWERS
◉Vibrio vulnificus. Answer: -GNR
-causes nec fas and sepsis, particularly in liver disease or
immunosuppressed pts
-hemorrhagic bullae
-exposure to warm sea or brackish water (Gulf of Mexico), seafood
drippings, consumption of raw seafood like oysters
◉CAP labs. Answer: -blood cx
-sputum cx
-influenza A&B rapid antigen test
-Legionella and strep pneumo urine antigen test
◉CURB65. Answer: Confusion, Uremia, RR, low BP, age>65
-0-1: outpt
-2: inpt
-3+: ICU
,◉CAP treatment. Answer: -outpt. previously health and no abx use
in last 3 mos: macrolide or doxy
-outpt. with comorbidites or hospitalized non-ICU: respiratory
fluoroquinolone OR b lactam + macrolide
-ICU: b lactam AND: resp. FQ or azithro
-treat for at least 5 days AND until pt. afebrile for 48-72 hrs and no
more than one abnormal vital sign
◉Risk factors for B lactam strep pneumo. Answer: -age less than 2
-age greater than 65
-B lactam in prior 3 mos
-EtOHism
-comorbidities
-immunosuppressed
-exposure to child in daycare
◉Risk factors for community-aquired MRSA. Answer: -ESRD
-injection drug use
-prior influenza
-prior abx
◉Aspiration PNA. Answer: gram negative enterics, oral anaerobes
,◉Alcoholic with PNA. Answer: strep pneumo, oral anaerobes,
Klebsiella pneumo, Acinetobacter, M. tuberculosis
◉COPD/smoker with PNA. Answer: H. flu, P. aeruginosa, Legionella,
S. pneumo, Moraxella, Chlamydophila pneumo
◉Exposure to bat or bird droppings. Answer: Histoplasma
capsulatum
◉Exposure to birds. Answer: Chlamydophila psittaci
◉Exposure to rabbits. Answer: Francisella tularensis
◉Exposure to farm animals or parturient cats. Answer: Coxiella
burnetii
◉Exposure to rodent poop. Answer: Hantavirus
◉Early HIV associated PNA. Answer: S. pneumo, H. flu, M.
tuberculosis
, ◉Late HIV associated PNA. Answer: Pneumocystis jirovecii,
Cryptococcus, Histoplasma, Aspergillus, atypical mycobacteria, P.
aeruginosa
◉Hotel or cruise ship stay in previous 2 weeks and PNA. Answer:
Legionella
◉Travel or residence in southwestern US and PNA. Answer: Cocci,
hantavirus
◉Travel or residence in SE or E Asia and PNA. Answer: Burkholderia
pseudomallei
◉IV drug use and PNA. Answer: S. aureus, anaerobes, M.
tuberculosis, S. pneumo
◉Endobroncial obstruction PNA. Answer: anaerobes, S. pneumo, H.
flu, S. aureus
◉Bronchiectasis or CF. Answer: Burkholderia cepacia, P. aeruginosa,
S. aureus
◉Bioterrorism. Answer: Bacillus anthracis, Yersenia pestis,
Francisella tularensis
EXAMINATION TEST 2026 FULL QUESTIONS
AND CORRECT ANSWERS
◉Vibrio vulnificus. Answer: -GNR
-causes nec fas and sepsis, particularly in liver disease or
immunosuppressed pts
-hemorrhagic bullae
-exposure to warm sea or brackish water (Gulf of Mexico), seafood
drippings, consumption of raw seafood like oysters
◉CAP labs. Answer: -blood cx
-sputum cx
-influenza A&B rapid antigen test
-Legionella and strep pneumo urine antigen test
◉CURB65. Answer: Confusion, Uremia, RR, low BP, age>65
-0-1: outpt
-2: inpt
-3+: ICU
,◉CAP treatment. Answer: -outpt. previously health and no abx use
in last 3 mos: macrolide or doxy
-outpt. with comorbidites or hospitalized non-ICU: respiratory
fluoroquinolone OR b lactam + macrolide
-ICU: b lactam AND: resp. FQ or azithro
-treat for at least 5 days AND until pt. afebrile for 48-72 hrs and no
more than one abnormal vital sign
◉Risk factors for B lactam strep pneumo. Answer: -age less than 2
-age greater than 65
-B lactam in prior 3 mos
-EtOHism
-comorbidities
-immunosuppressed
-exposure to child in daycare
◉Risk factors for community-aquired MRSA. Answer: -ESRD
-injection drug use
-prior influenza
-prior abx
◉Aspiration PNA. Answer: gram negative enterics, oral anaerobes
,◉Alcoholic with PNA. Answer: strep pneumo, oral anaerobes,
Klebsiella pneumo, Acinetobacter, M. tuberculosis
◉COPD/smoker with PNA. Answer: H. flu, P. aeruginosa, Legionella,
S. pneumo, Moraxella, Chlamydophila pneumo
◉Exposure to bat or bird droppings. Answer: Histoplasma
capsulatum
◉Exposure to birds. Answer: Chlamydophila psittaci
◉Exposure to rabbits. Answer: Francisella tularensis
◉Exposure to farm animals or parturient cats. Answer: Coxiella
burnetii
◉Exposure to rodent poop. Answer: Hantavirus
◉Early HIV associated PNA. Answer: S. pneumo, H. flu, M.
tuberculosis
, ◉Late HIV associated PNA. Answer: Pneumocystis jirovecii,
Cryptococcus, Histoplasma, Aspergillus, atypical mycobacteria, P.
aeruginosa
◉Hotel or cruise ship stay in previous 2 weeks and PNA. Answer:
Legionella
◉Travel or residence in southwestern US and PNA. Answer: Cocci,
hantavirus
◉Travel or residence in SE or E Asia and PNA. Answer: Burkholderia
pseudomallei
◉IV drug use and PNA. Answer: S. aureus, anaerobes, M.
tuberculosis, S. pneumo
◉Endobroncial obstruction PNA. Answer: anaerobes, S. pneumo, H.
flu, S. aureus
◉Bronchiectasis or CF. Answer: Burkholderia cepacia, P. aeruginosa,
S. aureus
◉Bioterrorism. Answer: Bacillus anthracis, Yersenia pestis,
Francisella tularensis
