Non-dermatophyte Dermatoses Mimicking Dermatophytoses in Animals.

This research article discusses dermatophytoses, a type of fungal skin disease in animals caused by Microsporum or Trichophyton dermatophyte fungi, and the various ways it can present itself, which can be quite variable, especially in cats.

Overview of Dermatophytoses

• Dermatophytoses are fungal diseases affecting the skin of animals, caused by fungi from the Microsporum or Trichophyton genus. The infection typically affects the follicles, leading to characteristic circular areas of hair loss (alopecia) accompanied by varying amounts of redness (erythema), skin flaking (scaling), and scabbing (crusting).

Clinical Presentation of Dermatophytoses

• The most commonly observed skin lesion in dermatophytoses is dermatophyte folliculitis, also known as ringworm. However, the manifestation of the disease can vary depending on the species of the host animal and the type of dermatophyte involved.
• The disease can present itself as scaling and crusting of the skin in cases where the infection is due to Microsporum persicolor. It can also take the form of a nodule in cases of kerion or mycetoma.
• In cats, dermatophytosis could lead to matted hairs, seborrheic dermatosis (a skin disorder causing scaly and flaky patches), or miliary dermatitis (characterized by the formation of multiple small bumps or scabs).
• Generalized exfoliative dermatoses, a condition causing widespread scaling or peeling of the skin, can occur in dogs, cats, and horses.
• The Devon Rex breed of cats can exhibit superficial non-follicular skin symptoms such as the formation of pustules (blisters containing pus), papules (small bumps), and macules (flat spots on the skin).
• An itching sensation (pruritus) could be a symptom of dermatophytoses in dogs, cats, and horses.
• Onychomycosis, a fungal infection of the nails, can occur in dogs, cats, and horses.

Diagnosing Dermatophytoses

• Given the wide range of symptoms that can present in dermatophytoses, the study advises considering the disease as a possible diagnosis in case of any annular (circular), papular, nodular, or pustular skin conditions, with or without hair loss, sometimes accompanied by itching. Nodular dermatoses should also be considered.