12th Ljudevit Jurak International Symposium on
Comparative Pathology
Zagreb
June 1-2, 2001
 

ABSTRACTS
MICROSPORUM CANIS IN THE CATS: INFECTION OR ILLNESS
M. Èerne, I. Zdovc, P. Juntes, M. Pogaènik
Veterinary faculty, Ljubljana, Slovenia
Aim: In cats, the majority of dermatophyte infections are caused by Microsporum canis. Due to the zoonotic nature of this agent special attention should be paid to the prevention and healing of dermatophytosis. This work focuses on prevalence of Microsporum canis in cats and on different diagnostic techniques we used to determine  the infected and the sick cats.
Methods: We used 100 randomly selected cats which died or were euthanasied for different reasons in the region of Ljubljana, Slovenia. All the cats were examined clinically, including Wood’s lamp. Hair samples for light and fluorescent microscopic examination as well as fungal culture were taken from both  ears, the frontlet, dorsal carpal region and from the cranial region of the thorax. Skin samples for the histologic examination were taken from the same regions.
Results: 68 cats had no clinical lesions on the skin and Wood’s lamp, cultural  and microscopic examinations were also negative. Skin lesions, specific and nonspecific, were found in 22 cats. In a 10 of them, M. canis was isolated and microscopicly found, Wood’s lamp was positive 3 times. On 12 of them cultural examination was negative in spite of  skin lesions. Cultural examination were positive in another 10 cats with any visible skin lesions. The microscopic examination of these cats were positive while only one was positive for Wood’s lamp screening. Altogether M. canis was found in 20 cats (20%). Using histologic examination M. canis was found in the hair follicles of 8 cats (8%). Seven of them had skin lesions and were also  cultural positive.
One of them was found in the group with no clinical signs and with negative cultural examination.
Conclusions: Dermatophytoses, especially caused by M. canis, are a common  in cats. Because the clinical signs may vary, a number of  diagnostic tests should be performed. The fungal culture is still the most reliable diagnostic method to establish the presence of M. canis. We found out that in our population of 100 cats, which were collected by chance, we got a high number of  positive cats (20%). Specific skin lesions and positive cultural examination confirmed the presence of the illness. Positive cultural examination with any visible lesions suspected that the clinically healthy cat is a source of infection for animals and humans. In our research we established 10 cats to be ill and 10 cats  only infected. Wood’s lamp was a useful screening tool as long as it was followed by microscopic examinations and fungal culture. We got a few positive results with Wood’s lamp according to positive cultural examination. Fungal elements in hair follicles and near dermatitis found in histologic examination was a morphologic confirmation of  the  illness.
References:
  1. Lunder M. et al.: Is Microsporum canis infection about to become a serious dermatological problem? Dermatology 1992; 184:87.
  2. Medleau L. et al.: Diagnosing dermatophytosis in dogs and cats. Vet Med 1992; 87:1086.
  3. Sparkes AH. et al.: Improved sensitivity in the diagnosis of dermatophytosis by fluorescence microscopy with calcofluor white. Vet Rec 1994; 134:307.
Program