A 62 year old Filipino male is referred to a gastroenterologist by his primary care physician for a screening colonoscopy for colon cancer.

He reports no major complaints to the GI doctor, including no fevers, chills sweats.

Review of systems: There has been no diarrhea, no weight loss, no blood in stool, constipation, change in caliber of stools or nausea and vomiting. There has been no shortness of breath or sputum production, other than an occasional cough in the morning for the last several months which he thinks might be from allergies. 12 point Review of Systems is otherwise negative.

PMHx: Seasonal allergies, Hyperlipidemia

Meds: Multivitamin daily, Atorvastatin

Social: No alcohol or smoking. Originally from the Philippines. Has lived in the US for more than 30 years. No recent travel. About 2 years ago, he went to the Philippines to visit family for three weeks. No contact concerns.

All: No known drug allergies

Family History: negative for Inflammatory Bowel Disease

Additional infectious disease hx: Up to date on vaccinations. Negative TB skin test when he entered the country. Doesn’t recall any testing afterwards.

Physical Examination: No significant findings

Colonoscopy: Patient had a screening colonoscopy and was found to have several significant ulcers near the splenic flexure. No active bleeding was seen and no other characteristic findings for Crohn’s disease.

Additional results:

Labs: HIV, Hep C, CBC with Diff, CMP: negative/normal

Pathology: (only fixed specimens were received)

Questions:

1. What structures are visualized on the H & E stains?
2. What is the special stain that was used and what is shown?
3. What additional studies are recommended to pursue?
4. What is the working diagnosis in this patient?

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