Rapid Review Laboratory Findings

Question 1

Paget disease of the breast (sign of underlying neoplasm)

Answer 1

Red, itchy, swollen rash of nipple/areola

Question 2

Emphysema (“pink puffer,” centriacinar [tobacco smoking] or panacinar [α1 -antitrypsin deficiency])

Answer 2

Pink complexion, dyspnea, hyperventilation

Question 3

Chronic bronchitis (hypertrophy and hyperplasia of mucus-secreting glands, “blue bloater”)

Answer 3

Hypoxemia, polycythemia, hypercapnia

Question 4

Sarcoidosis (noncaseating granulomas)

Answer 4

Bilateral hilar adenopathy, uveitis

Question 5

Cystic fibrosis (autosomal recessive mutation in CFTR gene Ž-> fat-soluble vitamin deficiency and mucous plugs)

Answer 5

Colonies of Pseudomonas in lungs

Question 6

Down syndrome

Answer 6

High β-hCG, low PAPP-A on first trimester screening

Question 7

Vitamin B 12 deficiency

Answer 7

High serum homocysteine, high methylmalonic acid, low folate

Question 8

Drug-induced lupus

Answer 8

Anti-histone antibodies

Question 9

Thymic aplasia (DiGeorge syndrome, velocardiofacial syndrome)

Answer 9

Low T cells, low PTH, low Ca2+, absent thymic shadow on CXR

Question 10

Optochin sensitivity

Answer 10

Sensitive: S pneumoniae; resistant: viridans streptococci

Question 11

Novobiocin response

Answer 11

Sensitive: S epidermidis; resistant: S saprophyticus

Question 12

Bacitracin response

Answer 12

Sensitive: S pyogenes (group A); resistant: S agalactiae (group B)

Question 13

Ghon complex (1° TB: Mycobacterium bacilli)

Answer 13

Hilar lymphadenopathy
Peripheral granulomatous lesion in middle or lower lung lobes (can calcify)

Question 14

Epiglottitis (Haemophilus influenzae)

Answer 14

“Thumb sign” on lateral neck x-ray

Question 15

Chagas disease (Trypanosoma cruzi)

Answer 15

Dilated cardiomyopathy with apical atrophy, megacolon, megaesophagus

Question 16

Infectious mononucleosis (EBV infection)

Answer 16

Atypical lymphocytes, heterophile antibodies

Question 17

Croup (parainfluenza virus)

Answer 17

Narrowing of upper trachea and subglottis (Steeple sign) on x-ray

Question 18

Negri bodies of rabies

Answer 18

Eosinophilic inclusion bodies in cytoplasm of hippocampal and cerebellar neurons

Question 19

Psammoma bodies

Answer 19

Meningiomas
Papillary thyroid carcinoma
Mesothelioma
Papillary serous carcinoma of the endometrium and ovary

Question 20

Tetralogy of Fallot (due to RVH)

Answer 20

“Boot-shaped” heart on x-ray

Question 21

Coarctation of the aorta

Answer 21

Rib notching (inferior surface, on x-ray)

Question 22

Wolff-Parkinson-White syndrome (bundle of Kent bypasses AV node)

Answer 22

“Delta wave” on ECG, short PR interval, supraventricular tachycardia

Question 23

Cardiac tamponade

Answer 23

Electrical alternans (alternating amplitude on ECG)

Question 24

“Orphan Annie” eyes nuclei (papillary carcinoma of the thyroid)

Answer 24

Empty-appearing nuclei with central clearing of thyroid cells

Question 25

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

Answer 25

“Brown” tumor of bone

Question 26

1° hyperaldosteronism (eg, Conn syndrome)

Answer 26

Hypertension, hypokalemia, metabolic alkalosis

Question 27

Celiac disease (diarrhea, weight loss)

Answer 27

Anti-transglutaminase/anti-gliadin/anti-endomysial antibodies

Question 28

“String sign” (Crohn disease)

Answer 28

Narrowing of bowel lumen on barium x-ray

Question 29

Ulcerative colitis (loss of haustra)

Answer 29

“Lead pipe” appearance of colon on abdominal imaging

Question 30

Familial adenomatous polyposis (autosomal dominant, mutation of APC gene)

Answer 30

Thousands of polyps on colonoscopy

Question 31

Colorectal cancer (usually left-sided)

Answer 31

“Apple core” lesion on barium enema x-ray

Question 32

Fatty liver disease (alcoholic or metabolic syndrome)

Answer 32

Triglyceride accumulation in liver cell vacuoles

Question 33

Wilson disease (hepatolenticular degeneration; KayserFleischer rings due to copper accumulation)

Answer 33

Low serum ceruloplasmin

Question 34

Megaloblastic anemia (vitamin B 12 deficiency: neurologic symptoms; folate deficiency: no neurologic symptoms)

Answer 34

Hypersegmented neutrophils

Question 35

Sideroblastic anemias, thalassemias

Answer 35

Basophilic stippling of RBCs

Question 36

Iron deficiency anemia, lead poisoning, thalassemia (fetal hemoglobin sometimes present)

Answer 36

Hypochromic, microcytic anemia

Question 37

β-thalassemia, sickle cell anemia (marrow expansion)

Answer 37

“Hair on end” (“crew cut”) appearance on x-ray

Question 38

Immune thrombocytopenia

Answer 38

Anti-GpIIb/IIIa antibodies

Question 39

DVT, DIC

Answer 39

High level of d-dimers

Question 40

Reed-Sternberg cells (Hodgkin lymphoma)

Answer 40

Giant B cells with bilobed nucleus with prominent inclusions (“owl’s eye”)

Question 41

Rheumatoid arthritis (systemic inflammation, joint pannus, boutonniere and swan neck deformities)

Answer 41

IgM antibody that targets IgG Fc region

Question 42

Pseudogout (calcium pyrophosphate dihydrate crystals)

Answer 42

Rhomboid crystals, ⊕ birefringent

Question 43

Gout (monosodium urate crystals)

Answer 43

Needle-shaped, ⊝ birefringent crystals

Question 44

Gout, Lesch-Nyhan syndrome, tumor lysis syndrome, loop and thiazide diuretics

Answer 44

High uric acid levels

Question 45

Lewy body (Parkinson disease and Lewy body dementia

Answer 45

Eosinophilic cytoplasmic inclusion in neuron

Question 46

Senile plaques (Alzheimer disease)

Answer 46

Extracellular amyloid deposition in gray matter of brain

Question 47

Parkinson disease (basal ganglia disorder: rigidity, resting tremor, bradykinesia)

Answer 47

Depigmentation of neurons in substantia nigra

Question 48

Neurofibrillary tangles (Alzheimer disease) and Pick bodies (Pick disease)

Answer 48

Protein aggregates in neurons from hyperphosphorylation of tau protein

Question 49

Glomerulonephritis

Answer 49

RBC casts in urine