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Guide to Feline Dermatolog)'

E. Guaguere

Ectoparasitic skin diseases

Skin diseases caused by mites and insects are of prime importance in feline dermatology and enter into the differential diagnosis of many different conditions. Although some are often suspected, others are less so because the signs associated with them are non-specific . Some ectoparasitic conditions may be the source of human infestations, unrecognised by either vet or dermatologist .

Notoedric mange

Aetiopathogenesis

Notoedric mange is caused by Notoedres cati, a mite from the family Sarcoptidae (Table 3:1). The mite lives in the epidermis¹ and its life cycle is similar to that of Sarcoptes scabiei. The condition is highly contagious, especially by direct contact, to cats, dogs and man (causing a pruritic rash) ². Although notoedric mange is now rare in European countries like Great Britain, Germany, The Netherlands, France (excluding the overseas territories), it is still common in parts of Italy, Switzerland, Spain, Slovenia and Croatia, where it is either endemic or present in an epizootie State. Young animals and cats debilitated with retroviral infection are particularly susceptible '.

Clinical features

Signs of notoedric mange appear initially on the face and pinnae and are characterised by hajr loss, erythema, scaling and thick crusts (a notoedric “helmet”) ^U4. With time, lesions spread to the limbs, abdomen and peri-anal region (Figs 3 : 1-4). Hyperpigmentation, lichenification and excoriations are then observed. Pruritus is variable (mild to severe) ^U4.

Diagnosis

Skin scrapings reveal numerous Notoedres mites - adults and immature stages (eggs, larvae and nymphs) (Table 3:1) (Fig. 3 : a). Faecal pellets are often seen.

Treatment

Amitraz ¹ (0.25%o solution) can be given every 5 days for 4 - 6 weeks following local washing with a keratolytic shampoo'.

Ivermectin ¹ (200-400 pg/kg), given once or twice (2 weeks apart), by subcutaneous injection, gives excellent results⁵. It should not be given to cats less than 4 months old.

Chlorinated hydrocarbons and organophosphates are toxic in this species and should be avoided \

Ali in-contact cats should be treated. Ivermectin is the treatment of choice when groups of cats are affected. The environment should be cleaned thoroughly with an acaricidal agent that gives long-lasting protection '.

This product is not licensed for use in the cat and responsibility for its use falls on the prescribing veterinary surgeon

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