A Retrospective Study Regarding the Treatment of Lupoid Onychodystrophy
in 30 Dogs and Literature Review
Am Anim Hosp Assoc 39[2]:139-150 Mar-Apr'03 Retrospective Study 27 Refs
Ralf S. Mueller, Dr.med.vet., DACVD; Rodney A.W. Rosychuk,
DVM, DACVIM; Leonard D. Jonas, DVM, DACVIM
Dept of Clinical Sciences, CVM and Biomedical Sciences, Colorado State University,
Fort Collins, CO 80523
Lupoid onychodystrophy is a relatively commonly encountered abnormality of the canine claw with characteristic clinical and histopathological findings. This syndrome seems to have multiple etiologies, and a number of treatment modalities have been reported. The purpose of this retrospective study was to evaluate the efficacy of various therapeutic options in 30 dogs diagnosed with lupoid onychodystrophy based on history, clinical examination, and histopathology.
Within these 30 dogs, miniature schnauzers, German shepherd dogs, and Labrador retrievers appeared to be over represented. The initial presenting complaints for all dogs were onychomadesis, onychodystrophy, and onychoschizia affecting multiple claws on all four feet. Biopsies were obtained by onychectomy or by a recently described procedure of onychobiopsy without onychectomy. In this study, 12 of 30 dogs had concurrent diseases documented, including hypothyroidism and allergy-related conditions, but their relationship to lupoid onychodystrophy remains unclear. Dogs were treated with fatty acid supplementation (n=18), doxycycline and niacinamide (n=12), tetracycline and niacinamide (n=10), pentoxifylline (n=6), prednisolone (n=5), azathioprine (n=1), clofazimine (n=1), or combinations thereof. An excellent response was seen in almost half of the patients treated with tetra- or doxycycline in combination with niacinamide. Six of the dogs were maintained successfully on fatty acid supplementation. It is of interest to note that almost half of the dogs with excellent responses stayed in complete remission even after therapy was discontinued.
Based on the results of this study, the authors recommend treating
dogs with lupoid onychodystrophy with appropriate antibacterials and/or food
elimination trials if history and diagnostics indicate. If response is poor,
then an 8-week trial of tetra- or doxycycline and niacinamide is warranted.
If there is insufficient response, this should be followed with an 8-week
trial of pentoxifylline or a fatty acid supplementation. In dogs with unresponsive
disease or with owners requesting immediate results, treatment with immunosuppressive
drugs, such as glucocorticoids, would be the treatment of choice. [Summary]
Potomac, Maryland 20854