ISSN 2398-2950      

Skin: dermatophytosis

ffelis

Synonym(s): Ringworm


Introduction

  • Cause: infection with Microsporum canis most common Microsporum canis .
  • Direct and indirect transmission.
  • Common zoonosis Ringworm: human .
  • Often self-limiting.
  • Signs: variable.
  • Treatment: responds to treatment with antifungal agents  Therapeutics: non-bacterial infection.
    Print off the owner factsheet on Ringworm  Ringworm  to give to your client.

Pathogenesis

Etiology

  • Microsporum canis is the most common cause Microsporum canis .
  • Trichophyton mentagrophytes Trichophyton spp.
  • Microsporum gypseum Microsporum gypseum.
  • Other dermatophytes are rare in the cat.
  • M. canis: source is usually infected cat.
  • T. mentagrophytes: source is rodents or their environment.
  • M. gypseum: inhabits rich soil; exposure occurs during digging in contaminated areas.

Predisposing factors

General

  • Immunosuppression.
  • Breed: Persian, other long-haired breeds.

Pathophysiology

  • Transmitted by contact with infected hair and scale, fungal elements in environment or on fomites.
  • Mechanical disruption of stratum corneum facilitates infection.
  • Fungal hyphae invade hair shaft and migrate downwards; they require actively growing hair to survive.
  • Host immune response determines clinical signs; often self-limiting in healthy cats. However, chronic infections are common in long-haired cats.
  • Arthrospores germinate within 6 hours of adherence to keratinocytes.
  • Skin microtrauma is necessary for infection.
  • Grooming eliminates arthrospores from skin.
  • Fungal growth in hair  →  keratinolytic enzymes  →  penetration of cuticle and hair shaft.
  • At keratogenous zone, fungus either reaches equilibrium with keratin production or is expelled.
  • When hair enters telogen phase or inflammatory response mounted  →  spontaneous resolution.
  • Toxins produced in stratum corneum  →  cutaneous inflammation.
  • Deeper penetration of keratin surface of epidermis  →  furunculosis  →  scarring.
  • Dermatophytic pseudomycetoma in Persian cats - sub-cutaneous nodules.

Epidemiology

  • Arthrospores of Microsporum canis remain infective for 18-24 months.
  • Infection may occur from direct contact with infected cats or via fomites.

Diagnosis

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Treatment

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Prevention

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Jacobson LS, McIntyre L, Mykusz J (2017) Comparison of real-time PCR with fungal culture for the diagnosis of Microsporum canis dermatophytosis in shelter cats: a field study. J Feline Med Surg 20 (2), 103-7 PubMed.
  • Jacobson LS, McIntyre L, Mykusz J (2017) Assessment of real-time PCR cycle threshold values in Microsporum canis culture-positive and culture-negative cats in an animal shelter: a field study. J Feline Med Surg 20 (2), 108-118 PubMed.
  • Moriello K A, Coyner K, Paterson S, Mignon B (2017) Diagnosis and treatment of dermatophytosis in dogs and cats: Clinical Consensus Guidelines of the World Association for Veterinary Dermatology. Vet Dermatol 28 (3), 266-e68 PubMed
  • Moriello K A, Leutenegger C M (2017) Use of a commercial qPCR assay in 52 high risk shelter cats for disease identification of dermatophytosis and mycological cure. Vet Dermatol 29 (1), 66-e26 PubMed.
  • Frymus T, Gruffydd-Jones T, Pennisi M G et al (2013) Dermatophytosis in Cats: ABCD guidelines on prevention and management. J Feline Med Surg 15 (7), 598-604 PubMed.
  • Garg J, Tilak R, Garg A et al (2009) Rapid detection of dermatophytes from skin and hair. BMC Res Notes 2, 60 PubMed.
  • Patel A, Lloyd D H & Lamport A I (2005) Survey of dermatophytes on clinically normal cats in the southeast of England. JSAP 46 (9), 436-439 PubMed.
  • Moriello K A (2004) Treatment of dermatophytosis in dogs and cats: review of published studies. Vet Dermatol 15 (2), 99-107 PubMed.
  • Sparkes A H, Robinson A, MacKay A D, Shaw S E (2000) A study of the efficacy of topical and systemic therapy for the treatment of feline Microsporum canis infection. J Feline Med Surg (3), 135-142 PubMed.
  • Mancianti F, Pedonese F, Millanta F et al (1999) Efficacy of oral terbinafine in feline dermatophytosis due to Microsporum canis. J Feline Med Surg (1), 37-41 PubMed.
  • Paterson S (1999) Miconazole/chlorhexidine shampoo as an adjunct to systemic therapy in controlling dermatophytosis in cats. JSAP 40 (4), 163-166 PubMed.
  • Greisen A (1998) Dermatophytosis - Incidence of subclinical dermatophytosis in cats living in households with human dermatophytosis. JSAP (2), 43-48 VetMedResource.

Other sources of information

  • Leutenegger C (2017) Validation of a qPCR Panel to aid in the diagnosis of dermatophytosis. Abstract presented at: European College of Veterinary Internal Medicine; September 14–16, 2017; St. Julian, Malta.
  • Miller W H, Griffin C E & Campbell K L (2013) Dermatophytosis. In: Muller & Kirk's Small Animal Dermatology 7th edition, Elsevier, St Louis. pp 231-243.

Related Images

OWNER FACTSHEETS

Ringworm

Want more related items, why not
contact us

Can’t find what you’re looking for?

We have an ever growing content library on Vetlexicon so if you ever find we haven't covered something that you need please fill in the form below and let us know!

 
 
 
 

To show you are not a Bot please can you enter the number showing adjacent to this field

 Security code