Pathology 1 and 2

Question 1

H&E
hematoxylin

Answer 1

blue/purple
IS basic
binds to acids, BASOPHILIC substances

like nucleic acids (DNA, RNA) in nucleus

Question 2

H&E
eosin

Answer 2

red/pink
IS acidic,
binds to bases, ACIDOPHILIC substances

like proteins with lysine and arginine in cytoplasm

Question 3

How is H&E useful in diagnosis? What example was used in class?

Answer 3

hepatocellular carcinoma

we see abnormal enlarged nuclei and nucleoli, with mutated DNA (bluer)

cytoplasm has more rRNA, so more basophilic (less red and more purple than usual)

Question 4

How is H&E useful in necrosis and apoptosis?

Answer 4

more intense staining with eosin (hypereosinophilic)

less rRNA (destroyed), so less blue
proteins denatured, bind more eosin
cell contracted, more concentrated cytoplasmic proteins

Question 5

Prussian blue stain

Answer 5

stain for IRON
stains ferric iron deposit tissues in blue

liver with hemachromatosis = lots of iron, a genetic disease associated with hepatocellular CA and cirrhosis

Question 6

Masson trichrome

Answer 6

for collagen + fibrosis

BLUE collagen
red muscle
light red or pink cytoplasm
dark blue nuclei

Question 7

Ziehl-Neelsen

Answer 7

for acid-fast bacilli like M.tuberculosis

Question 8

Grocott

Answer 8

fungal organisms (silver stain that reacts with carbohydrate capsule) like for aspergillus infection in lung transplant patient

Question 9

CD (cluster differentiation) molecules

Answer 9

CD number is assigned to a group of monoclonal ABs that recognize a given cell surface molecular and corresponding to a particular cellular-differentiation pattern

large B-cell lymphoma stained with Anti-CD20 = surface membrane marker of B-lymphocytes and B cell lymphoma

predicts response to anti-CD20 Ab Rituxan = predictive marker

Question 10

IHC and Cytoplasmic Proteins

Answer 10

keratins = provide structural framework of cell and are anchors for intercellular junctions

Question 11

IHC and Nuclear Proteins

Answer 11

estrogen receptor (ER), helpful in diagnosis of breast cancer, and a predictive marker of response to ER antagonists (Tamoxifen)

Question 12

Immunofluorescence

Answer 12

for Ags sensitive to loss by paraffin embedding = done on frozen sections

looking for IgA, IgM and IgG in renal glomerular diseases

Question 13

Transmission electron microscopy

Answer 13

very high resolution, need ultra thin sections

mainly used in renal glomerular diseases, also in virology

Question 14

Cytopathology - gynecologic

Answer 14

Pap smears

Question 15

Cytopathology - non-gynecologic

Answer 15

fine needle aspirates
exfoliative (pleural and peritoneal fluids, bronchial washes and brushes, urine, CSF, etc)

Question 16

Cytopathology - procedures

Answer 16

procedures, methods of sampling, fixation and processing are DIFFERENT from surgical pathology

uses smears, cytocentrifuge, etc (if enough tissue can make cell blocks used for IHC)