Chronic pododermatitis and interdigital furunculosis in dogs

Abstract

Chronic pododermatitis with interdigital furunculosis is a common and frustrating problem in dogs. It is characterised by the presence of recurrent interdigital furunculosis. It is a multifactorial condition with primary, predisposing and perpetuating causes that lead to the secondary infections. Almost any skin disease can trigger the initial inflammation, but atopic dermatitis, adverse food reactions and abnormal conformation are the most common. Predisposing factors such as short hairs, excess weight, and altered weight bearing may lead to the development of the interdigital furunculosis. Perpetuating changes prevent resolution; these include weight bearing on haired skin, conjoined pads, new pad formation, deep tissue pockets, ingrown hairs and sinus tracts. All of the contributing factors in each case must be identified and managed. Supportive care includes analgesia, weight loss, using boots, keeping the interdigital skin clean, and using lubricating creams. Secondary bacterial and/or Malassezia spp. infections should be managed with appropriate topical and/or systemic antimicrobials. Bacterial infections can be deep, mixed and/or antimicrobial resistant, and culture and antimicrobial susceptibility testing must be used to select effective drugs. Chronic inflammatory changes can be managed with topical or systemic glucocorticoids, topical 0.1% tacrolimus, ciclosporin or cytotoxic drugs. Chronic proliferative changes are poorly responsive to medical management alone, therefore surgical fusion or laser podoplasties should be considered. Long-term treatment of the primary, predisposing and perpetuating problems is required to maintain remission and prevent recurrence.

First known case of canine focal metatarsal fistulation in a Shikoku dog

“…On the other hand, at presentation there were erythematous and crusted lesions near the metatarsal pad of the left hind leg (see Figure 1), and traumatic hair loss presumably secondary to weight bearing on haired skin that persisted post treatment in this region. Similar lesions showing traumatic hair loss and weight bearing on haired skin have been present in previous reports 2,3 but not specifically commented on, and suggest that traumatic folliculitis and furunculosis may be a cause for canine metatarsal fistulation 4 . However, the specific cause for traumatic folliculitis and furunculosis in this case was not clear 4 .…”

“…4 However, the specific cause for traumatic folliculitis and furunculosis in this case was not clear. 4 In the future, the relationship between canine metatarsal fistulation and traumatic folliculitis and furunculosis should be considered.…”

“…Similar lesions showing traumatic hair loss and weight bearing on haired skin have been present in previous reports 2,3 but not specifically commented on, and suggest that traumatic folliculitis and furunculosis may be a cause for canine metatarsal fistulation. 4 However, the specific cause for traumatic folliculitis and furunculosis in this case was not clear. 4 In the future, the relationship between canine metatarsal fistulation and traumatic folliculitis and furunculosis should be considered.…”

Use of surgical lasers in small animal dermatology

“…The interdigital furuncles are either excised or ablated; the remaining tissue is allowed to heal by second intention and scarring. This technique removes the offending hair follicles which are believed to be a key contributing factor for this disease (Duclos and others 2008, Nuttall 2019). Healing can be slow, taking up to around six weeks although, due to the advantages of the CO 2 laser, the dog is much more comfortable in the long run (Figs 13, 14).…”

“…Chronic pododermatitis and interdigital furunculosis, also known as interdigital cysts (although this is inaccurate, as they are not technically cysts) and pedal folliculitis/furunculosis, is a multifaceted disease with chronic inflammation from ruptured hair follicles as the root cause (Nuttall 2019). The lesions may wax and wane; over time they lead to significant pain and discomfort for the dog.…”