USMLE STEP 3 EXAM QUESTIONS AND
ANSWERS 100% PASS.
Pseudogout associations - ANS hemochromatosis, hyperparathyroidism, acromegaly,
hypothyroidism
Gout crystals - ANS negatively birefringent needles
Pseudogout crystals - ANS positively birefringent needles
Vasculitis associated with chronic Hep B - ANS polyarteritis nodosa
Vasculitis associated with chronic Hep C - ANS cryoglobulinemia
Best blood test for polyarteritis nodosa - ANS There is none. Get abdominal angiography first,
then biopsy of muscle, skin, or sural nerve.
Churg-Strauss - ANS vasculitis + eosinophilia + asthma
Takayasu's arteritis - ANS young asian female with diminished pulses (usually preceeded by
fatigue, weight loss, arthralgia, anemia, elevated ESR)
Best test for Takayasu's - ANS aortic angiography or MRA
2026 STUDY MATERIAL @COPYRIGHT RESERVED 1
,Bite cells on blood smear - ANS G6PD
Burr/Spur cells on blood smear - ANS liver disease
Acanthocytes on blood smear (looks like spur cell but with more rounded spurs) - ANS liver
disease, hypothyroidism, alcoholism
Basophilic stippling on blood smear - ANS lead poisoning
Schistocytes on blood smear - ANS TTP-HUS, DIC, prosthetic heart valve, malignant htn,
sepsis
Target cells on blood smear - ANS thalassemia, other hemoglobinopathies, liver disease
5 causes of microcytic anemia - ANS iron deficiency, lead poisoning, anemia of chronic
disease (but usually normocytic), thalassemia, sideroblastic anemia (can also have high MCV)
Antibody test for celiac disease - ANS anti-endomysial, tissue transglutaminase (small bowel
bx is best though)
Antibiotics for MRSA - ANS IV: vanc, linezolid, daptomycin, tigecycline;
if minor infection, can use oral: TMP/SMX, doxy, minocycline, or maybe clindamycin (there is
inducible resistance to clinda though)
Antibiotics for MSSA - ANS Oxacillin/nafcillin, dicloxacillin (IV and oral), cefazolin (IV),
cephalexin (oral)
Can you use cephalosporins in pt allergic to PCN? - ANS yes, if the rxn is rash only; no if pt has
true anaphylaxis
2026 STUDY MATERIAL @COPYRIGHT RESERVED 2
,Antibiotics to use for Staph with PCN allergy - ANS cephalosporins if rash only; macrolides,
clindamycin, vancomycin, linezolid, daptomycin, TMP/SMX
Antibiotics for strep - ANS PCN, ampicillin, amoxicillin
Antibiotics for GNRs - ANS Cephalosporins: cefepime, ceftazidime
PCNs: piperacillin, ticaricillin
Monobactam: Aztreonam
Quinolones: cipro, levo, gati, moxi
Aminoglycs: gentamicin, tobramycin, amikacin
Carbapenems: imipenem, mero, erta
Limitation of ertapenem - ANS does NOT cover pseudomonas
Piperacillin and ticarcillin - ANS GNRs
strep
anaerobes
Carbapenems - ANS good anaerobic coverage
strep
MSSA
Tigecycline - ANS MRSA
good GNR coverage
Anaerobes - ANS -metronidazole is BEST for abdominal anaerobes (carbapenems, piperacillin,
and ticarcillin have equal efficacy)
-cefoxitin and cefotetan are the ONLY cephalosporins
-respiratory anaerobes: clindamycin
2026 STUDY MATERIAL @COPYRIGHT RESERVED 3
, Abx with NO anaerobic coverage - ANS aminoglycs, aztreonam, fluoroquinolones,
oxacillin/nafcillin, all cephalosporins EXCEPT cefoxitin and cefotetan
Red man syndrome - ANS red, flushed skin from histamine release, associated with rapid
infusion of vancomycin (so slow down the infusion rate)
Osteomyelitis - ANS -most common is staph: oxacillin or nafcillin IV for 4-6 wks for MSSA;
vanc, linezolid or dapto for MRSA
-GNRs: salmonella or pseudomonas, can use orals, but must cx org. first and make sure it is
sensitive (BONE bx and cx)
Cellulitis tx - ANS -minor infection: oral dicloxacillin or cephalexin
-severe: IV oxacillin, nafcillin or cefazolin
-PCN allergy: if rash, then cephalosporin; if anaphylaxis, then vanc, linezolid, dapto (macrolides
or clinda for minor infection)
Sequelae of strep infection - ANS -throat: rheumatic fever AND glomerulonephritis
-skin: ONLY glomerulonephritis
Gonorrhea tx - ANS -ceftriaxone IM
-cefixime oral
-cefpodoxime oral
-ciprofloxacin oral (2d line)
-if pregnant, then ceftriaxone IM
-ALSO treat for chlamydia
Chlamydia tx - ANS -azithromycin (single dose)
-doxycycline (for 1 wk)
-if pregnant, then azithro
2026 STUDY MATERIAL @COPYRIGHT RESERVED 4
ANSWERS 100% PASS.
Pseudogout associations - ANS hemochromatosis, hyperparathyroidism, acromegaly,
hypothyroidism
Gout crystals - ANS negatively birefringent needles
Pseudogout crystals - ANS positively birefringent needles
Vasculitis associated with chronic Hep B - ANS polyarteritis nodosa
Vasculitis associated with chronic Hep C - ANS cryoglobulinemia
Best blood test for polyarteritis nodosa - ANS There is none. Get abdominal angiography first,
then biopsy of muscle, skin, or sural nerve.
Churg-Strauss - ANS vasculitis + eosinophilia + asthma
Takayasu's arteritis - ANS young asian female with diminished pulses (usually preceeded by
fatigue, weight loss, arthralgia, anemia, elevated ESR)
Best test for Takayasu's - ANS aortic angiography or MRA
2026 STUDY MATERIAL @COPYRIGHT RESERVED 1
,Bite cells on blood smear - ANS G6PD
Burr/Spur cells on blood smear - ANS liver disease
Acanthocytes on blood smear (looks like spur cell but with more rounded spurs) - ANS liver
disease, hypothyroidism, alcoholism
Basophilic stippling on blood smear - ANS lead poisoning
Schistocytes on blood smear - ANS TTP-HUS, DIC, prosthetic heart valve, malignant htn,
sepsis
Target cells on blood smear - ANS thalassemia, other hemoglobinopathies, liver disease
5 causes of microcytic anemia - ANS iron deficiency, lead poisoning, anemia of chronic
disease (but usually normocytic), thalassemia, sideroblastic anemia (can also have high MCV)
Antibody test for celiac disease - ANS anti-endomysial, tissue transglutaminase (small bowel
bx is best though)
Antibiotics for MRSA - ANS IV: vanc, linezolid, daptomycin, tigecycline;
if minor infection, can use oral: TMP/SMX, doxy, minocycline, or maybe clindamycin (there is
inducible resistance to clinda though)
Antibiotics for MSSA - ANS Oxacillin/nafcillin, dicloxacillin (IV and oral), cefazolin (IV),
cephalexin (oral)
Can you use cephalosporins in pt allergic to PCN? - ANS yes, if the rxn is rash only; no if pt has
true anaphylaxis
2026 STUDY MATERIAL @COPYRIGHT RESERVED 2
,Antibiotics to use for Staph with PCN allergy - ANS cephalosporins if rash only; macrolides,
clindamycin, vancomycin, linezolid, daptomycin, TMP/SMX
Antibiotics for strep - ANS PCN, ampicillin, amoxicillin
Antibiotics for GNRs - ANS Cephalosporins: cefepime, ceftazidime
PCNs: piperacillin, ticaricillin
Monobactam: Aztreonam
Quinolones: cipro, levo, gati, moxi
Aminoglycs: gentamicin, tobramycin, amikacin
Carbapenems: imipenem, mero, erta
Limitation of ertapenem - ANS does NOT cover pseudomonas
Piperacillin and ticarcillin - ANS GNRs
strep
anaerobes
Carbapenems - ANS good anaerobic coverage
strep
MSSA
Tigecycline - ANS MRSA
good GNR coverage
Anaerobes - ANS -metronidazole is BEST for abdominal anaerobes (carbapenems, piperacillin,
and ticarcillin have equal efficacy)
-cefoxitin and cefotetan are the ONLY cephalosporins
-respiratory anaerobes: clindamycin
2026 STUDY MATERIAL @COPYRIGHT RESERVED 3
, Abx with NO anaerobic coverage - ANS aminoglycs, aztreonam, fluoroquinolones,
oxacillin/nafcillin, all cephalosporins EXCEPT cefoxitin and cefotetan
Red man syndrome - ANS red, flushed skin from histamine release, associated with rapid
infusion of vancomycin (so slow down the infusion rate)
Osteomyelitis - ANS -most common is staph: oxacillin or nafcillin IV for 4-6 wks for MSSA;
vanc, linezolid or dapto for MRSA
-GNRs: salmonella or pseudomonas, can use orals, but must cx org. first and make sure it is
sensitive (BONE bx and cx)
Cellulitis tx - ANS -minor infection: oral dicloxacillin or cephalexin
-severe: IV oxacillin, nafcillin or cefazolin
-PCN allergy: if rash, then cephalosporin; if anaphylaxis, then vanc, linezolid, dapto (macrolides
or clinda for minor infection)
Sequelae of strep infection - ANS -throat: rheumatic fever AND glomerulonephritis
-skin: ONLY glomerulonephritis
Gonorrhea tx - ANS -ceftriaxone IM
-cefixime oral
-cefpodoxime oral
-ciprofloxacin oral (2d line)
-if pregnant, then ceftriaxone IM
-ALSO treat for chlamydia
Chlamydia tx - ANS -azithromycin (single dose)
-doxycycline (for 1 wk)
-if pregnant, then azithro
2026 STUDY MATERIAL @COPYRIGHT RESERVED 4
