Banca de QUALIFICAÇÃO: PAULA DIAS RETAMERO

Anatomopathological evaluation and retrospective study of granulomatous/pyogranulomatous dermatitis diagnosed in dogs and cats at the Pathological Anatomy Sector at UFRRJ from 1994 to 2022

dermatopathology; canine,; feline

Dermatological diseases are among the most common conditions in the clinical routine of small animals. Among these, we can find granulomatous and pyogranulomatous inflammations, which are chronic responses triggered by the presence of exogenous agents that are generally perceived as foreign bodies. Diseases reported in the literature include cases of sporotrichosis, leishmaniasis, mycobacteriosis, cryptococcosis, demodicosis, nocardiosis, sterile panniculitis, sterile pyogranuloma, neosporosis, pseudomycetoma, canine sarcoidosis, and others. Among the granulomatous/pyogranulomatous diseases, sporotrichosis stands out, a fungal disease caused by dimorphic fungi found in the environment of the Sporothrix schenckii species complex: S. schenckii sensu stricto, S. brasiliensis, S. globosa and S. luriei, which has been observed in Brazil with cases described in humans and cats reported in 25 of the 26 Brazilian states. Rio de Janeiro currently reports the highest number of cases in Brazil, with 4,517 human cases, 4,916 feline cases and 244 canine cases reported in Rio de Janeiro, with sample collection dates from 1991 to 2017. The aim of this study was to perform a retrospective anatomopathological study of dermatitis classified in the SAP/UFRRJ from 1994 to 2022 as granulomatous and/or pyogranulomatous in canine and feline species. The following criteria were evaluated: analysis of history, age, breed, sex, coat color, location, macroscopic and microscopic descriptions of lesions, diagnosis, possible differential diagnoses, and special stains. Additionally, a survey of bacterial or fungal culture results was performed, in addition to performing the polymerase chain reaction (PCR) technique to elucidate and/or confirm the diagnosis of the selected cases. As preliminary results, 90 cases in dogs and 22 cases in cats diagnosed as granulomatous or pyogranulomatous dermatitis were analyzed. Of the results obtained in dogs, regarding sex, 44 males and 46 females were evaluated. The dogs were between 9 months and 17 years old and more than half were between 5 and 12 years old (54.4%, 49/90). In 2 cases, information was given on adult animals and, in 3, the age was not reported. Regarding breeds, the majority were of mixed breed (38), followed by Pitbull (10), Poodle (10), Yorkshire (3), Dalmatian (2), Labrador (2), Lhasa Apso (2), Dachshund (2), Weimaraner (1), Schnauzer (1), Chow-chow (1), American Bully (1), German Shepherd (1), Fox Paulistinha (1), Boxer (1), French Bulldog (1), Beagle (1), Bull Terrier (1), Cocker Spaniel (1), Shih-tzu (1). The coat colors were: white and black (7), white (6), white and brown (6), black (5), striped (5), yellow (5), gray (4), brown and black (4), brown (2), yellow and black (1), white and gray (1), not reported (22). Regarding the evolution of the disease, the following times were compiled: 6 days (1), 20 days (2), 21 days (1) 1 month (10), 2 months (5), 3 months (6), 4 months (7), 5 months (2), 6 months (6), 7 months (1), 1 year (7), 1 year and a half (1), 2 years (7), 3 years (2), 5 years (1), 29 cases were not there was information on the evolution time. The lesions were located on the nasal bridge (22), hind limb (13), dorsal region (10), thorax (9), thoracic limb (8), scrotum (5), scrotum (5), generalized (5), lumbar (4), digit (4), lip (4), abdomen (6), near the mammary gland (4), flank (3), paw (3), ear (2), base of the tail (2), neck (1), face (1), prepuce (1), cushion (1), periocular (1), eyelid (1), not reported (3). Regarding macroscopy, the color, shape of the external surface, consistency and appearance of the lesion upon cutting were evaluated. Regarding the color of the lesions, the following results were obtained: white (38), yellow (13), brown (11), white and yellow (6), yellow and brown (5), white and brown (4), white and red (3), white and gray (2), red (1), yellow and gray (1), gray (1), pink (1), gray and black (1), not informed (13). Regarding the shape of the external surface, the following aspects were described: irregular (41), cylindrical (3), exophytic (1), not informed (33). Regarding consistency: firm (33), soft (21), firm-elastic (9), elastic (1), not informed (16). Regarding the cut appearance: compact (45), smooth (19), homogeneous (11), granular (3), not informed (22). Of the lesions, 48 had ulcers, 39 did not have ulcers, and 13 had no information. Regarding microscopic lesions, the following results were obtained: predominantly neutrophilic inflammation (84) and absent (6); with the presence of macrophages (75) or epithelioid (15); presence of lymphocytes (47) or absent (43); mast cells (82) or absent (8); plasma cells (43) or absent (47); eosinophils (13) or absent (77); giant cells (11) or absent (79); granuloma formation (8) or absent (82); intralesional necrosis (77) or absent (13); fibrosis (21) or absent (69). Regarding the intensity of the lesions: mild (4), moderate (14) or severe (72) and focal distribution (20), multifocal (44), diffuse (26). Regarding the cats, 13 males and 9 females were evaluated. These were between 1 and 10 years of age, with one third of the animals being between 4 and 8 years of age (36.36%, 8/22); in 4 cases it was reported that they were adults and, in another 4, the age was not reported. All cats were SRD (no defined breed). The coat colors were: black (3), white and black (3), brindle (3), yellow (1), and in 12 cases there was no information. Regarding the progression of the disease, the following times were evaluated: 1 month (1), 3 months (1), 6 months (3), 2 years (1), 3 years (1), and in 14 cases there was no information. The lesions were described on the back (6), nasal bridge (4), hind limb (3), ear (2), abdomen (2), flank (1), eyelid (1), scapular region (1), forelimb (1) and snout (1). Regarding the color of the lesions, these were described as white (8), brown (3), white and brown (1), yellow and brown (1), yellow (1), white and black (1) and not reported (7). Regarding the consistency, there were soft lesions (8), firm lesions (7), and in 7 cases this information was not available. The lesions were compact (7), homogeneous (3), multinodular (2), smooth (1), granular (1) and, in 9 cases, there was no description. In 14 cases, there was ulceration, in 6 the lesions were not ulcerated and, in 2 cases, there was no information. Regarding the microscopic lesions, we obtained the following results: predominant neutrophilic inflammation (21) and absent (1); with macrophages (18) or epithelioid (4); lymphocytes (9) or absent (13); mast cells (3) or absent (19); plasma cells (10) or (12); eosinophils (7) or absent (15); giant cells (3) or absent (19); granuloma formation (3) or absent (19); intralesional necrosis (5) or absent (17); fibrosis (7) or absent (15); lesion with mild (1), moderate (3) or marked (18) intensity; focal (4), multifocal (13) or diffuse (5) distribution. Of the 90 cases analyzed in dogs, 10 were positive for periodic acid-Schiff (PAS) histochemistry. Among the 22 samples from cats, 5 were positive in PAS. Regarding fungal culture, 14 cases were positive for the Sporothrix schenckii complex in dogs. The remaining analyses are ongoing.