Just Ask the Expert: Anal sacculitis refractory to standard treatment

Dr. Bloom welcomes dermatology questions from veterinarians and veterinary technicians.

Click here to submit your question, or send an e-mail to vm@advanstar.com with the subject line "Dermatology questions."

I am treating a 5-year-old Great Dane that has anal sacculitis. Standard treatment consisting of cephalexin; an antibacterial, anti-inflammatory, and antifungal ointment; and a tapering dosage of hydrocortisone has been unsuccessful. I'm trying to avoid surgery. Any ideas?

A. Before increasing your systemic therapy dosages or performing more frequent local treatments, you should ensure that the anal sacs are the real problem. Anal pruritus unrelated to anal sacs can mimic the clinical signs of anal sacculitis, but the two are distinguishable. If anal sacculitis is truly the problem, the pruritus should resolve after the anal sacs are expressed.

Dr. Paul Bloom

Conflicting reports exist regarding the value of gross and cytologic examination of anal sac exudates in diagnosing anal sacculitis. This is because of the extreme heterogenicity in color, consistency, amount of solid material, inflammatory cells, bacteria, yeast and RBCs contained in the expressed secretions from both normal1 and affected dogs. Some reports correlated anal sacculitis with the presence of large numbers of nondegenerative neutrophils and intracellular bacteria.2,3 However, in the most recent study,4 there were dogs with anal sac disease that had minimal to no inflammation nor bacteria present on cytology, and there were normal dogs with large numbers of inflammatory cells and bacteria present on cytology.4 Thus the numbers of inflammatory cells and bacteria are not statistically different between normal dogs and dogs with anal sac disease.

Anal sacculitis may be associated with allergies, perianal fistulas, and gastrointestinal disease, particularly if the stools are not well-formed. It may also be idiopathic.

Recommended initial treatment protocols include frequent manual expression of the anal sacs, an increase in dietary fiber, locally infused combination antibiotic and corticosteroid products, and systemic use of corticosteroids. For grossly infected anal sacs, systemic antimicrobials may be initiated but are rarely effective.

For refractory cases, anal sacculectomy is frequently the best treatment option.

Paul Bloom, DVM, DACVD, DABVP

Allergy, Skin and Ear Clinic for Pets

31205 Five Mile

Livonia, MI 48154

REFERENCES

1. Lake AM, Scott DW, Miller WH Jr, et al. Gross and cytological characteristics of normal canine anal-sac secretions. J Vet Med A Physiol Pathol Clin Med 2004;51(5):249-253.

2. Robson DC, Burton GG, Lorimer MF. Cytological examination and physical characteristics of the anal sacs in 17 clinically normal dogs. Aust Vet J 2003;81(1-2):36-41.

3. Pappalardo E, Martino PA, Noli C. Macroscopic, cytological and bacteriological evaluation of anal sac content in normal dogs and in dogs with selected dermatological diseases. Vet Dermatol 2002;13(6):315-322.

4. James DJ, Griffin CE, Polissar NL, Neradilek MB. Comparison of anal sac cytological findings and behaviour in clinically normal dogs and those affected with anal sac disease. Vet Dermatol 2011;22(1):80-87.