Efficacy of itraconazole as a combined continuous/pulse therapy in feline dermatophytosis: preliminary results in nine cases

This study evaluated the efficacy of itraconazole as a combined continuous/pulse therapy for feline dermatophytosis. Nine cats with dermatophytosis caused by Microsporum canis were treated with itraconazole at 10 mg kg(-1) orally once daily for 28 days and then on an alternate week regimen (1 week off, 1 week on) at the same dosage. Cats were re-evaluated by physical examination and fungal culture at days 28, 42, 56 and 70 if necessary. Treatment was stopped when two consecutive negative fungal cultures were obtained. Eight cats were cured after 56 days, with two negative cultures obtained at days 28 and 42. In one case, a positive culture was obtained at day 28, but negative cultures were achieved at days 42 and 56. This protocol appears to be effective in the treatment of feline dermatophytosis, although these preliminary results should be confirmed by a controlled study.     

Dermatophyte granulomas caused by Trichophyton mentagrophytes in a dog

Multiple, dermal and subcutaneous nodules developed in a young female Manchester Terrier dog that had a chronic history of superficial dermatophytosis. Skin biopsy specimens of the nodules revealed granulomatous inflammation in the deep dermis and subcutis with branching fungal organisms. Cultures of multiple biopsy specimens from the nodules all yielded Trichophyton mentagrophytes. The lesions in this dog were similar to granulomatous dermatophytosis, a skin disease that has been reported in Persian cats and one Yorkshire Terrier dog.     

Treatment of dermatophytosis in dogs and cats: review of published studies

The recent literature on the treatment of dermatophytosis in dogs and cats was reviewed. Based upon in vitro studies using isolated infected hairs and controlled or field in vivo studies, the following topical treatments were consistently found to be antifungal (i.e. antidermatophyte): lime sulfur (1:16), 0.2% enilconazole rinses, and a combined 2% miconazole/chlorhexidine shampoo. Animals or hairs were either bathed or rinsed once or twice weekly. Itraconazole, griseofulvin and terbinafine were evaluated in controlled or field studies, most commonly involving cats. Griseofulvin (50 mg kg(-1)) was reported to cure infected animals in 41-70 days. Itraconazole (10 mg kg(-1) once daily or in a combined daily/pulse therapy 10 mg kg(-1) once daily for 28 days and then week on/week off) was reported to cure infected animals in 56-70 days. Low-dose itraconazole (1.5-3.0 mg kg(-1)) in 15-day cycles required 1-3 cycles (15-45 days). Various doses of terbinafine (5-40 mg kg(-1)) were reportedly used to treat dogs or cats. The higher doses of terbinafine (> 20 mg kg(-1)) were required to achieve a mycological cure; the number of treatment days to cure varied from 21 to > 126 days. Lufenuron was reported anecdotally to be an effective cure, however, this was not substantiated in controlled studies. Finally, fungal vaccines were not found to be effective against challenge exposure, however, there is evidence that they may be useful in treatment protocols.     

Efficacy of pre-treatment with lufenuron for the prevention of Microsporum canis infection in a feline direct topical challenge model

Oral lufenuron is reportedly an effective treatment for some cats with dermatophytosis. The purpose of this study was to determine if lufenuron, when used as a pre-treatment prior to challenge exposure, would be protective against the development of infection after the direct topical application of fungal macrocondia (Microsporum canis spores). Three groups (n = 6/group) of juvenile cats were treated with either monthly oral lufenuron (30 or 133 mg/kg) or placebo. After 2 months of treatment, kittens were challenged using 10(5)Microsporum canis spores applied to the skin under occlusion. Cats were examined weekly and the following data collected: Wood's lamp examination; scoring for scale/crust, erythema and induration; lesion size; and the development of satellite lesions. Fungal cultures were performed bi-weekly. All cats became infected; the infections progressed, and then regressed, in a similar fashion in all groups. There were no consistent statistically significant differences in weekly infection scores between treated and untreated cats throughout the study. Treated cats did not recover faster than untreated cats. We conclude that oral lufenuron at the dosing schedule and conditions used in this study did not prevent dermatophytosis or alter the course of infection by direct topical challenge.     

健康猫被毛真菌菌相

定量检测了４０只临床健康猫的被毛真菌菌相,从３１只猫被毛上共分离出１１个属１７５株真菌,主要为交链孢霉属、芽枝孢霉属、犬小孢子菌和曲霉属等。皮肤病病原菌２个属３个种,包括犬小孢子菌、红色毛癣菌和石膏样毛癣菌。     

Cutaneous xanthomas with concurrent demodicosis and dermatophytosis in a cat

Multiple cutaneous xanthomas, associated with fasting hyperlipidaemia, are described in a 9-month-old domestic long-haired cat. A severely pruritic, papular, and crusting dermatitis affecting the head and neck, initially diagnosed as lesions of the eosinophilic granuloma complex, progressively developed on the head and pinnae. Pruritus was controlled with administration of prednisolone and chlorambucil. Repeat histological examination confirmed the diagnosis of cutaneous xanthoma and concurrent mild demodicosis. Marked fasting hypercholesterolaemia, hypertriglyceridaemia and transient hyperglycaemia were subsequently confirmed. Treatment for hyperlipidaemia and xanthomas with a low-fat diet (Hill's Feline r/d) and the previously unreported treatment for feline demodicosis of daily oral milbemycin were commenced. Multiple pink, alopecic plaques and papules gradually regressed, however pruritus recurred if immunosuppressive treatment was reduced, and well-demarcated areas of alopecia developed on the head, limbs and trunk, despite negative skin scrapings for demodex mites. Fungal culture of hair samples yielded Microsporum canis. All cutaneous lesions resolved with the addition of griseofulvin to the treatment regimen. Concurrent corneal ulceration and keratoconjunctivitis sicca ultimately resolved with treatment, including topical cyclosporin. Diabetes mellitus developed 6 months after resolution of skin lesions. No cutaneous or ocular abnormalities were present 6 months later with continued low-fat diet and insulin administration, although transient recurrence of papules and pruritus occurred after inadvertent access to a fatty meal. An underlying primary hyperlipidaemia was suspected, causing pruritic xanthomas. This may represent the first report of concurrent cutaneous xanthomas, demodicosis and dermatophytosis in a cat.     

Alopecia in the horse – an overview

Dr Stannard explains different forms of alopecia in the horse with emphasis on the hair follicle and its function in the production of hairs. Both normal and abnormal patterns of hair growth and shedding in the horse are reviewed. Overviews of several specific hair follicle abnormalities, both inflammatory and noninflammatory, are discussed in detail with their clinical relevance. Some of the clinical entities covered in this section (linear alopecia and alopecia areata) are caused by immunological attack against normal structures and could have been placed in Immunologic diseases. However, because the clinical presentation for these entities is alopecia, Dr Stannard chose to include them in his notes on alopecia. Other inclusions in this section include cutaneous bacterial infections (e.g. pastern folliculitis and dermatophilosis) as well as fungal infections of the hair (dermatophytosis).     

Mycologic disorders of the skin

Cutaneous tissue can become infected when fungal organisms contaminate or colonize the epidermal surface or hair follicles. The skin can be a portal of entry for fungal infection when the epithelial barrier is breached or it can be a site for disseminated, systemic fungal disease. The two most common cutaneous fungal infections in small animals are dermatophytosis and Malassezia dermatitis. Dermatophytosis is a superficial cutaneous infection with one or more of the fungal species in the keratinophilic genera Microsporum, Trichophyton, or Epidermophyton. Malassezia pachydermatis is a nonlipid dependent fungal species that is a normal commensal inhabitant of the skin and external ear canal in dogs and cats. Malassezia pachydermatis is the most common cause of Malassezia dermatitis. The diagnosis and treatment of these cutaneous fungal infections will be discussed.     

Practical applications of topical therapy for allergic, infectious, and seborrheic disorders

Topical therapy is extremely important in the management of allergic, infectious, and seborrheic disorders. It can be used as a sole therapy or adjunctive therapy for these disorders, often minimizing the need for systemic therapy. In allergic diseases, pruritus can be decreased by removing allergen, desensitizing the skin or other antipruritic effects. Many agents can also maintain or replace moisture to the skin and have emollient effects. When used for infectious conditions, topical therapy can decrease microbial counts and reduce surface colonization of microbes and help to prevent relapses. Antiseborrheic products function by normalizing keratinocyte turnover rates by reducing epidermal division (keratoplastic), normalizing keratinization, and increasing desquamation (keratolytic). There are many different topical vehicles and modes of application: shampoos, whirlpools, soaks, rinses, sprays, lotions, gels, creams, and ointments. Shampoos are often the most practical and effective. The practitioner needs to become familiar with many active ingredients to learn what products are indicated for specific diseases.     

A rapid molecular method for diagnosing epidemic dermatophytosis in a racehorse facility

Reasons for performing study: Identification of the species and strain of dermatophyte can play an effective role in control of disease outbreaks by establishing the source of infection. Current methods of identification are based on cultural and microscopic methods, often involving weeks before a positive identification are made. A rapid molecular diagnostic method would therefore be an important laboratory technique, but requires confirmation in equine clinical practice. Objectives: To test the sensitivity and specificity of molecular diagnostic methods applied to a racehorse herd from the Korean Racehorse Authority (KRA). Methods: A total of 57 DNA samples were collected from hairs and crusts of skin lesions in KRA racehorses with histories and clinical signs suggestive of dermatophytosis, which was confirmed by dermatophyte‐specific PCR amplification analysis using the primer pair for the chitin synthase 1 (CHS1) gene. Results: Thirty‐eight racehorses were definitively diagnosed with dermatophytosis using molecular and traditional diagnostic methods. PCR fingerprinting profiles using simple repetitive (GACA)₄ primers showed that all diagnosed horses had the same pattern profile. Oligonucleotide sequencing of CHS1 gene PCR products confirmed Trichophyton mentagrophytes as the infectious agent. Conclusions: This study demonstrates that the PCR‐based molecular diagnostic method is sensitive and specific and offers fast precise diagnosis of dermatophytosis in horses.