Clinical history
41 year old man, watery diarrhea and abdominal pain.
Site
Colon biopsy.
Primary image
Intermediate magnification. H&E stain.
High magnification

High magnification. H&E stain.

Very high magnification

Very high magnification. H&E stain.

Differential diagnosis
Additional tests
More history
More history

No family history of IBD. Diarrhea several weeks. Well prior to diarrhea. Medications: one antihypertensive.

Ask a friend
Ask a friend

Did you see anything at high magnification?

Stains
Alcian blue/PAS to Bilirubin 

Test  Result 
Alcian blue/PAS  Dr Torres would ask why! 
Alican blue pH 1.0  Dr Torres would ask why! 
Alcian blue pH 2.5  Dr Torres would ask why! 
Auramine  Dr Torres would ask why! 
Bielchowsky  Dr Torres would ask why! 
Bilirubin  Dr Torres would ask why! 



Colloidal iron to FontanaMasson 

Test  Result 
Colloidal iron  Dr Torres would ask why! 
Congo red  Dr Torres would ask why! 
Cresyl violet  Dr Torres would ask why! 
Dieterle  Dr Torres would ask why! 
Diff Quik  Dr Torres would ask why! 
FontanaMasson  Dr Torres would ask why! 



Gallyas to Gremelius 

Test  Result 
Gallyas  Dr Torres would ask why! 
Giemsa  Dr Torres would ask why! 
GMS  Dr Torres would ask why! 
Gomori's trichrome  Dr Torres would ask why! 
Gram  Dr Torres would ask why! 
Gremelius  Dr Torres would ask why! 



JMS to Mucicarmine 

Test  Result 
JMS  Dr Torres would ask why! 
Jones  Dr Torres would ask why! 
Kinyoun  Dr Torres would ask why! 
Luxol fast blue  Dr Torres would ask why! 
Masson trichrome  Dr Torres would ask why! 
MMAS  Dr Torres would ask why! 
Movat  Dr Torres would ask why! 
Mucicarmine  Dr Torres would ask why! 



Oil red O to Prussian blue 

Test  Result 
Oil red O  Dr Torres would ask why! 
Orecein  Dr Torres would ask why! 
PAS  Dr Torres would ask why! 
PASD  Dr Torres would ask why! 
PASF  Dr Torres would ask why! 
PTAH  Dr Torres would ask why! 
Prussian blue  Dr Torres would ask why! 



Reticulin to ZiehlNeelsen 

Test  Result 
Reticulin  Dr Torres would ask why! 
Sudan black B  Dr Torres would ask why! 
Toluidine blue  Dr Torres would ask why! 
Verhoeff  Dr Torres would ask why! 
Von Kossa  Dr Torres would ask why! 
WarthinStarry  Spirochetes 
ZiehlNeeslen  Dr Torres would ask why! 



IHC
Alpha1 AT to Cathepsin K 

Test  Result 
alpha1 AT  Dr T would ask why! 
ACTH  Dr T would ask why! 
AE1/AE1  Dr T would ask why! 
alphafetoprotein  Dr T would ask why! 
AlkI  Dr T would ask why! 
AMACR  Dr T would ask why! 
AR  Dr T would ask why! 
ATRX  Dr T would ask why! 
Beta2microglobulin  Dr T would ask why! 
B72.3  Dr T would ask why! 
Betacatenin  Dr T would ask why! 
BCL2  Dr T would ask why! 
BCL6  Dr T would ask why! 
BCLxL  Dr T would ask why! 
C3 comp  Dr T would ask why! 
CA9  Dr T would ask why! 
Calcitonin  Dr T would ask why! 
Calponin  Dr T would ask why! 
Calretinin  Dr T would ask why! 
CAM5.2  Dr T would ask why! 
Cathepsin K  Dr T would ask why! 



CD10 to Chromogranin 

Test  Result 
CD10  Dr T would ask why! 
CD117  Dr T would ask why! 
CD138  Dr T would ask why! 
CD15  Dr T would ask why! 
CD1a  Dr T would ask why! 
CD20  Dr T would ask why! 
CD21  Dr T would ask why! 
CD23  Dr T would ask why! 
CD3  Dr T would ask why! 
CD30  Dr T would ask why! 
CD31  Dr T would ask why! 
CD34  Dr T would ask why! 
CD35  Dr T would ask why! 
CD4  Dr T would ask why! 
CD43  Dr T would ask why! 
CD45 (LCA)  Dr T would ask why! 
CD5  Dr T would ask why! 
CD56  Dr T would ask why! 
CD57  Dr T would ask why! 
CD68  Dr T would ask why! 
CD7  Dr T would ask why! 
CD79a  Dr T would ask why! 
CD8  Dr T would ask why! 
CD99  Dr T would ask why! 
CDX2  Dr T would ask why! 
CEAm  Dr T would ask why! 
Chromogranin  Dr T would ask why! 



CK17 to Glypican 3 

Test  Result 
CK17  Dr T would ask why! 
CK19  Dr T would ask why! 
CK20  Dr T would ask why! 
CK34betaE12  Dr T would ask why! 
CK5/6  Dr T would ask why! 
CK7  Dr T would ask why! 
CMV  Dr T would ask why! 
cMYC  Dr T would ask why! 
Cyclin D1  Dr T would ask why! 
D240  Dr T would ask why! 
Desmin  Dr T would ask why! 
DOG1  Dr T would ask why! 
EBV  Dr T would ask why! 
EMA  Dr T would ask why! 
ER and PR  Dr T would ask why! 
Factor VIII  Dr T would ask why! 
Factor XIIIa  Dr T would ask why! 
Fascin  Dr T would ask why! 
FH  Dr T would ask why! 
FSH  Dr T would ask why! 
Gastrin  Dr T would ask why! 
GATA3  Dr T would ask why! 
GCDFP15 (BRST2)  Dr T would ask why! 
GFAP  Dr T would ask why! 
GH  Dr T would ask why! 
Glucagon  Dr T would ask why! 
Glypican3  Dr T would ask why! 



HBME1 to IgM 

Test  Result 
HBME1  Dr T would ask why! 
HBV core  Dr T would ask why! 
HBV surface  Dr T would ask why! 
Hcaldesmon  Dr T would ask why! 
HCG  Dr T would ask why! 
Helicobacter  Dr T would ask why! 
Hepatocyte  Dr T would ask why! 
HER2/neu  Dr T would ask why! 
HHV8  Dr T would ask why! 
HMB45  Dr T would ask why! 
HNF1beta  Dr T would ask why! 
HPV  Dr T would ask why! 
HSVI  Dr T would ask why! 
HSVII  Dr T would ask why! 
IDH1  Dr T would ask why! 
Inhibin  Dr T would ask why! 
INI1 (BAF47)  Dr T would ask why! 
Insulin  Dr T would ask why! 
Kappa  Dr T would ask why! 
Ki67  Dr T would ask why! 
Lambda  Dr T would ask why! 
Leu 7  Dr T would ask why! 
IgA  Dr T would ask why! 
IgG  Dr T would ask why! 
IgM  Dr T would ask why! 



LH to PDGFR 

Test  Result 
LH  Dr T would ask why! 
LIN28  Dr T would ask why! 
Lysozyme  Dr T would ask why! 
mammoglobin  Dr T would ask why! 
MAP2  Dr T would ask why! 
MCV  Dr T would ask why! 
Melanin A  Dr T would ask why! 
MHC class I  Dr T would ask why! 
MITF  Dr T would ask why! 
MUM1  Dr T would ask why! 
Myeloperoxidase  Dr T would ask why! 
MYO D1  Dr T would ask why! 
Myoglobin  Dr T would ask why! 
Napsin  Dr T would ask why! 
NF  Dr T would ask why! 
NKX3.1  Dr T would ask why! 
NSE  Dr T would ask why! 
OCT3/4  Dr T would ask why! 
p16  Dr T would ask why! 
P501S  Dr T would ask why! 
p53  Dr T would ask why! 
p57  Dr T would ask why! 
p63  Dr T would ask why! 
Pankeratin  Dr T would ask why! 
PAX2  Dr T would ask why! 
PAX5  Dr T would ask why! 
PAX8  Dr T would ask why! 
PCNA  Dr T would ask why! 
PDGFR  Dr T would ask why! 



PLAP to WT1 

Test  Result 
PLAP  Dr T would ask why! 
PNL2C  Dr T would ask why! 
Prolactin  Dr T would ask why! 
PSA  Dr T would ask why! 
PSAP  Dr T would ask why! 
RCC  Dr T would ask why! 
S100  Dr T would ask why! 
SALL4  Dr T would ask why! 
Smooth muscle actin  Dr T would ask why! 
Somatostatin  Dr T would ask why! 
STAT6  Dr T would ask why! 
Synaptophysin  Dr T would ask why! 
TdT  Dr T would ask why! 
TFE3  Dr T would ask why! 
TFEB  Dr T would ask why! 
Thyroglobulin  Dr T would ask why! 
Toxoplasma  Dr T would ask why! 
TSH  Dr T would ask why! 
TTF1  Dr T would ask why! 
Ubiquitin  Dr T would ask why! 
UCHL1 (PGP9.5)  Dr T would ask why! 
Ulex Europaeus  Dr T would ask why! 
Vimentin  Dr T would ask why! 
VIP  Dr T would ask why! 
VZV  Dr T would ask why! 
WT1  Dr T would ask why! 



Diagnosis
Other cases


 Number  

 Subspecialty (Difficulty) 
Autopsy pathology (jr,sr, f/e)
Breast pathology (jr,sr, f/e)
Cardiovascular pathology (jr,sr, f/e)
Cytopathology (jr,sr, f/e)
Dermatopathology (jr,sr, f/e)
Endocrine pathology (jr,sr, f/e)
Forensic pathology (jr,sr, f/e)
Gastrointestinal pathology (jr,sr, f/e)
Genitourinary pathology (jr,sr, f/e)
Gynecologic pathology (jr,sr, f/e)
Hematopathology (jr,sr, f/e)
Head and neck pathology (jr,sr, f/e)
Lymph node pathology (jr,sr, f/e)
Medical kidney pathology (jr,sr, f/e)
Molecular pathology (jr,sr, f/e)
Neuropathology (jr,sr, f/e)
Pediatric pathology (jr,sr, f/e)
Pulmonary pathology (jr,sr, f/e)
Placental pathology (jr,sr, f/e)
Soft tissue pathology (jr,sr, f/e) 

 Difficulty  

