Antonella Souza Mattei

Epidemiological Findings and Laboratory Evaluation of Sporotrichosis: A Description of 103 Cases in Cats and Dogs in Southern Brazil

Sporotrichosis is a subcutaneous mycosis, which affects mainly small animals, and is considered an important public health disease. This paper describes the epidemiological and laboratory characteristics of 103 clinical cases of sporotrichosis diagnosed over a 10-year period in southern Brazil. The 92 cats and 11 dogs from eight municipalities in Rio Grande do Sul State developed especially the disseminated cutaneous and fixed cutaneous forms of the disease. Respiratory signs such as sneezing, serous nasal discharge and dyspnea were found in about 57% of the animals. The detection of Sporothrix schenckii in different clinical samples showed highest isolation in testicles (46.6%), oral cavity (45.2%) and conjunctival mucosa (38.1%). A differentiated histological pattern was found between the fixed cutaneous and disseminated cutaneous (DC) manifestations of the disease; well-organized granulomas of nodular distribution and various fungal structures prevailed in the DC form in cats. Melanin detection in S. schenckii cells by the Fontana–Masson technique was positive in 45.4% of the samples. The study revealed that the State of Rio Grande do Sul is an endemic sporotrichosis area and demonstrated the possibility of involvement of other pathways in the infection and spread of the disease. In addition, it emphasized the importance of laboratory tests for mycosis confirmation, especially in dogs that develop clinical manifestations without the presence of cutaneous lesions.

Feline Sporotrichosis in the Southern Region of Rio Grande Do Sul, Brazil: Clinical, Zoonotic and Therapeutic Aspects

Clinical cases of feline sporotrichosis, originating in the Pelotas region and diagnosed at the Laboratory of Infectious Diseases (UFPel), were studied in the period from 2002 to 2006. The animals were evaluated according to the clinical forms of the mycosis, time of lesion appearance, severity of the clinical diagnosis and evolution of cutaneous lesions throughout the treatment period. Mycological analyses, carried out through direct examination, cultivation of tissue samples and exudates of feline lesions all confirmed the diagnosis of sporotrichosis in the 15 animals under study. The cutaneous dissemination form was observed in 10 animals, of which three showed prostration, anorexia and dehydration. The zoonosis occurred in 20% of case studies, and the pet owners and one attendant at a veterinary clinic were infected, developing the fixed and disseminated cutaneous forms. The treatment of mycosis was carried out with itraconazole, 10 mg kg−1, once a day, on 12 animals. The cure of the clinical symptoms was observed on 50% of the felines. This study demonstrates a good clinical response of felines with sporotrichosis, when they were treated itraconazole and calls the attention for the incidence of human sporotrichosis on people related to the veterinary activity as well as for pet owners.

Role of melanin in the pathogenesis of cutaneous sporotrichosis.

In this study, we evaluate the clinical, histopathological and ultra structural aspects of the infection by field strain (MEL(+)) and mutated strain (MEL(-)) of Sporothrix schenckii. The development of sporotrichosis at the inoculation sites was similar for both groups of animals after the second week of the experimental period. Statistical differences appeared only at weeks 3 and 5. The pigmented isolate had greater tissue invasive capacity, promoting the formation of multifocal granulomas, whereas the albino isolate induced an enhanced inflammatory response, restraining the agent to the core of the granulomas.

Clinical and mycological analysis of dog's oral cavity

The oral microbiota of humans and animals is made up of a wide variety of yeasts and bacteria, but microbiota of dogs is not totally described. Although such identification is an important step to establish the etiopathogenesis and adequate therapy for the periodontal disease The aim of this study was to evaluate and correlate oral alterations with the presence of yeasts in oral cavity of female dogs. After clinical evaluation samples from healthy and from dogs with oral diseases were obtained from three different oral sites by swabs, curettes, millimeter periodontal probes and HA membrane tip in cellulose ester. Yeast identification was performed through macroscopic and microscopic colony features and biochemical tests. Dental calculus was the most prevalent occurrence in the oral cavity of 59 females. However, the isolation of yeasts was significantly higher (p < 0.05) in animals suffering from halitosis. Eleven yeast species were identified, namely: Malassezia pachydermatis, Rhodotorula spp., Candida albicans, C. catenulata, C. famata, C. guilliermondii, C. parapsilosis, C. intermedia, Trichosporon asahii, T. mucoides and Cryptococcus albidus. It could be concluded that the yeasts are part of the microbiota from the different sites of the oral cavity of the female canines studied without causing any significant alterations except halitosis.

Isolation of dermatophytes in wild felids from screening centers

The aim of this study was detect the presence of dermatophyte fungi on wild felids from screening centers. Samples were taken from 30 animals, assembled in two groups: “free-ranging” and “transitory captivity”. The dermatophytes (Trichophyton genus), isolated from two felids (6.6%), both of the group “free-ranging”.

Sporothrix schenckii in a hospital and home environment in the city of Pelotas/RS - Brazil

This study describes the isolation of S. schenckii in hospital and home environments in Brazil. Samples were collected from surfaces of a veterinary service place and at home. S. schenckii was detected in 1.5% of the samples from the hospital environment. However, this fungus was isolated from all sampled areas in home environments. The isolation of S. schenckii demonstrates that these surfaces could act as infection sources to animals and humans. Therefore, employees and pet owners could be exposed to this agent, and the contamination, through surfaces, could occur through the traumatic inoculation of the fungus or by direct contact with pre-existing lesions.

In vitro activity of disinfectants against Aspergillus spp

Fungi of the Aspergillus genus are widespread and contaminate the environment. Thousands of conidia are released from each phialide and dispersed in the air every day. These fungi are considered important mycose-causing agents in hospitals. Due to this, research to determine prevalent fungi from the Aspergillus genus in hospital environments, and an adequate disinfection program in these areas is are needed. This study evaluated the susceptibility of Aspergillus spp. isolated from a veterinary environment against four disinfectants. Successive dilutions of disinfectants (log2) were used according to CLSI M38-A2 microdilution technique adapted to chemical agents against 18 isolates of this genus. After 72 hours of incubation, the Minimum Inhibiting Concentration and Minimum Fungicidal Concentration capable of inhibiting 50% and 90% of the isolates were determined. Chlorexidine-cetrimine, benzalconium chloride and a chlorophenol derivative proved to be effective against all isolates with a lower MIC than that suggested by the manufacturer, except for the A. flavus strain. Sodium hypochlorite was ineffective against three A. fumigatus, three A. flavus and one A. niger isolate. These results demonstrated that all studied disinfectants were effective against environmental isolates, with the exception of sodium hypochlorite, which showed lower effectiveness.