Classic Labs/Findings

Question 1

Findings:
Anticentromere antibodies.

Diagnosis?

Answer 1

Scleroderma (CREST)

Question 2

Findings:
Anti-desmoglein (epithelial) antibodies.

Diagnosis?

Answer 2

Pemphigus vulgaris (blistering)

Question 3

Findings:
Anti-glomerular basement membrane antibodies.

Diagnosis?

Answer 3

Goodpasture syndrome (glomerulonephritis and hemoptysis)

Question 4

Findings:
Anti-histone antibodies.

Diagnosis?

Answer 4

Drug-induced SLE (e.g. hydralazine, isoniazid, phenytoin, procainamide)

Question 5

Findings:
Anti-IgG antibodies.

Diagnosis?

Answer 5

Rheumatoid arthritis (systemic inflammation, joint pannus, boutonniere deformity)

Question 6

Findings:
Anti-mitochondrial antibodies (AMAs).

Diagnosis?

Answer 6

Primary biliary cirrhosis (female, cholestasis, portal hypertension)

Question 7

Findings:
Anti-neutrophil cytoplasmic antibodies (ANCAs).

Diagnosis?

Answer 7

p-ANCA:

• Microscopic polyangiitis
• Eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome)

c-ANCA:
* Granulomatosis with polyangiitis (Wegener syndrome)

Question 8

Findings:
Antinuclear antibodies (ANAs: anti-Smith and anti-dsDNA).

Diagnosis?

Answer 8

SLE (type III hypersensitivity)

Question 9

Findings:
Antiplatelet antibodies.

Diagnosis?

Answer 9

Idiopathic thrombocytopenic purpura

Question 10

Findings:
Anti-topoisomerase antibodies.

Diagnosis?

Answer 10

Diffuse systemic scleroderma

Question 11

Findings:
Anti-transglutaminase, anti-gliadin, anti-endomysial antibodies.

Diagnosis?

Answer 11

Celiac disease (diarrhea, weight loss)

Question 12

Findings:
“Apple core” lesion on barium enema x-ray.

Diagnosis?

Answer 12

Colorectal cancer (usually L-sided)

Question 13

Findings:
Atypical lymphocytes.

Diagnosis?

Answer 13

EBV

Question 14

Findings:
Azurophilic peroxidase positive granular inclusions in granulocytes and myeloblasts.

Diagnosis?

Answer 14

Auer rods (AML, especially the M3 [promyelocytic] type)

Question 15

Findings:
Bacitracin response.

Diagnosis?

Answer 15

Sensitive: S. pyogenes (group A)
Resistant: S. agalactiae (group B)

Question 16

Findings:
“Bamboo spine” on x-ray.

Diagnosis?

Answer 16

Ankylosing spondylitis (chronic inflammatory arthritis; HLA-B27)

Question 17

Findings:
Basophilic nuclear remnants in RBCs.

Diagnosis?

Answer 17

Howell-Jolly bodies (due to splenectomy or nonfunctional spleen)

Question 18

Findings:
Basophilic stippling of RBCs.

Diagnosis?

Answer 18

Lead poisoning or sideroblastic anemia

Question 19

Findings:
Bloody or yellow tap on lumbar puncture.

Diagnosis?

Answer 19

Subarachnoid hemorrhage

Question 20

Findings:
“Boot-shaped” heart on x-ray.

Diagnosis?

Answer 20

Tetralogy of Fallot (due to RVH)

Question 21

Findings:
Branching gram-positive rods with sulfur granules.

Diagnosis?

Answer 21

Actinomyces israelii

Question 22

Findings:
Bronchogenic apical lung tumor on imaging.

Diagnosis?

Answer 22

Pancoast tumor (can compress cervical sympathetic chain and cause Horner syndrome)

Question 23

Findings:
“Brown” tumor of bone.

Diagnosis?

Answer 23

Hyperparathyroidism or osteitis fibrosa cystica (deposited hemosiderin from hemorrhage gives brown color)

Question 24

Findings:
Cardiomegaly with apical atrophy.

Diagnosis?

Answer 24

Chugs disease (Trypanosoma cruzi infection)

Question 25

Findings:
Cellular crescents in Bowman capsule.

Diagnosis?

Answer 25

Rapidly progressive crescentic glomerulonephritis