Case to perform biopsies
When should you perform a biopsy? Do so when your patient presents with:
- Hair loss: Alopecia in a very unusual distribution (without pruritus) that does not appear to be related to obvious Cushing's
or hypothyroidism. Diseases include alopecia X, follicular dysplasia, alopecia areata, cutaneous manifestations of internal
disease (feline pancreatic paroneoplastic alopecia, etc.)
- Suspected autoimmune skin diseases (usually involve the face, pinnae, paw pads etc.)
- Any neoplastic or pre-neoplastic process
- Any disease that affects the subcutaneous tissue (deep skin disease)
- Skin diseases refractory to appropriate therapies.
Rules of biopsy
Always take at least three biopsy samples, preferably 6-mm punches. Never submit one-punch biopsy; pathologists need more
than that to allow proper diagnosis. Never biopsy the edge of a lesion unless the other samples submitted are from the center
of lesions. Exception: ulcerative skin disease would be an example to perform a biopsy from the edge of a lesion. In cases
of alopecia, biopsy in the worst areas of hair loss.
Finally, please give the pathologist a complete history. This is critical! Be descriptive and mention distribution and symmetry
and whether pruritus is present or not.
This list is by no means the final word on how to practice dermatology. Some of these tips are based upon experience, and
some are based upon published science. Either way, I hope these suggestions will allow you to practice higher quality medicine
and see far fewer fleas on your patients.
Dr. Vitale received his veterinary degree from Mississippi State University, College of Veterinary Medicine. He completed
a residency in veterinary dermatology at the University of California, Davis and is a diplomate of the American College of
Veterinary Dermatology. He is a clinical instructor/lecturer at UC-Davis and a staff dermatologist at East Bay Veterinary
Specialists (formerly Encina Veterinary Hospital), Bay Area Veterinary Specialists and San Francisco Veterinary Specialists.