Diferencia en la población de células cebadas de glándulas apocrinas de sacos anales de perros adultos y seniles / Difference in the population of mast cells of anal sac apocrine glands of adult and senile dogs

Se estudió la población de células cebadas (CC) presentes en sacos anales de perros adultos y seniles mediante su conteo en cortes de tejido procesado con la técnica de inclusión en parafina y teñidos con azul de toluidina. El promedio de CC obtenido para el grupo de perros adultos jóvenes fue de 18,16 +/- 7,58 (n=12 perros) y para el grupos de adultos maduros fue de 73,75 +/- 16,29 (n=12 perros). Al comparar el número de células de ambos grupos con la prueba de U Mann-Withney se encontró que son significativamente diferentes (P< 0,0001), siendo mayor en el grupo de perros seniles. Esta mayor población de CC puede estar relacionada con una mayor susceptibilidad de los perros seniles a reacciones inflamatorias del tejido de los sacos anales causadas por cambios en la dieta, obesidad y diarrea crónica.

We studied the population of mast cells (CC) present in anal sacs of adult and senile dogs by its count in tissue processed with the technique of embedding in paraffin and stained with toluidine blue. The average CC obtained for the group of adult dogs (n=12) was 18.16 +/- 7.58 and for group of senile dogs (n=12) was 73.75 +/- 16.29. When comparing the number of cells in both groups with Mann-Whitney U test were found to be significantly different (P0.0001), being higher in the group of senile dogs. The largest population of CC may be related to an increased susceptibility of senile dogs to inflammatory reactions in the tissue of the anal sacs caused by changes in diet, obesity and chronic diarrhea.

Histochemical properties of sialic acids and antimicrobial substances in canine anal glands.

The functional properties of sialic acids appear to be manifold. Additionally, antimicrobial substances serve as a non-specific defense against microorganisms. In this study, therefore, the localization of sialic acids and antimicrobial substances in the anal glands of dog was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium, luminal secretions and excretory ducts exhibited high levels of sialoglycoconjugates that terminated in Siaα2-6Gal/GalNAc or Siaα2-3Gal1-4GlcNAc. Additionally, O-acetylated sialic acids were detectable in these glandular structures. Antimicrobial substances, such as lysozyme, immunoglobulin A (IgA), lactoferrin and the peptide group of ß-defensins, were also demonstrated as products of the anal glands. The results obtained are discussed with regard to the functional significance of the anal glands. These secretory products may create a defensive barrier against microbial invasion at the anal mucosa.

Comparison of anal sac cytological findings and behaviour in clinically normal dogs and those affected with anal sac disease.

No previous study has explored the relationship between cytology and the frequency of behaviours associated with anal sac disease (ASD). The goals of the study were: (i) to compare the cytological findings between anal sac secretions from normal dogs with no history of ASD to those with non-neoplastic ASD; (ii) to determine whether anal sac cytological findings can be used to differentiate between normal dogs and dogs with ASD; (iii) to explore the correlation of anal sac cytology and behaviour between normal dogs and dogs with ASD; and (iv) to describe behaviours typical of ASD as reported by owners. Thirty dogs were selected for this study, based on their behavioural history as detailed in a questionnaire completed by their owners. Of the thirty dogs, ten were considered normal insofar as they had no history of ASD clinical signs. The remaining 20 dogs were characterized as having ASD, with a chronic history of perianal pruritus, but no other pruritus. All dogs had their anal sacs manually expressed, and the discharge was examined microscopically in a blinded manner. A total of 171 oil immersion fields (OIFs) were examined from normal dogs and 333 OIFs from dogs with ASD. The behavioural results for dogs with ASD revealed that scooting recurred with a median frequency of 3 weeks post-anal sac expression. There were no clinically statistically significant cytological differences between normal dogs and those with ASD, thereby leading to the conclusion that cytology is an ineffective tool for diagnosing ASD.

Gross and cytological characteristics of normal feline anal-sac secretions.

This study was conducted to characterize the gross and cytological characteristics of secretions from normal feline anal sacs. Thirty cats with no recent history of anal-sac disease were selected consecutively and their anal sacs manually expressed. The color, cell counts, or presence of solid portions of the secretions in the youngest cats (<1 year old) were not significantly different from the rest. Young cats (<1 year old) tended to more often have watery secretions. The secretions contained 13 (median) epithelial cells per 600x magnification microscopic field, basophilic background debris, and a mixture of Gram-positive cocci (83 per field; median), Gram-negative cocci (38 per field; median), and Gram-negative rods (1.8 per field; median). Most secretions had occasional neutrophils, and a minority of cats had occasional yeasts in their secretion. Erythrocytes were found only rarely. Extreme heterogeneity existed in gross color, consistency, and amount of solid material. Hence, these latter parameters would not be valid indicators of anal-sac disease.

Gross and cytological characteristics of normal canine anal-sac secretions.

A study was conducted to characterize the gross and cytological characteristics of secretions from normal canine anal sacs. Fifty dogs with no recent history of anal-sac disease were selected consecutively and their anal sacs manually expressed. Of the 47 dogs with known or estimated ages, 27 were < 1 year olds. However, these youngest dogs were not significantly different from the rest in cell counts, viscosity, or presence of dark or light solid portions of the secretions. For all dogs combined, the secretions typically contained 41 (median) corneocytes per 400x magnification microscopic field, lots of basophilic background debris, and a mixture of Gram-positive cocci (173 per field; median), Gram-positive rods (29 per field; median), and Gram-negative rods (two per field; median). Although median counts across 10 400x fields per sac indicated no leucocytes or yeasts, many of the normal dogs had an occasional 400x field with non-degenerate neutrophils and yeasts. Erythrocytes were not a feature of these anal-sac secretions, and mononuclear leucocytes were found only rarely. Extreme heterogeneity existed in gross colour, consistency and the amount of solid material. Thus, these latter parameters probably would not be valid indicators of anal-sac disease.

Cytological examination and physical characteristics of the anal sacs in 17 clinically normal dogs.

OBJECTIVE: To quantify numbers of leucocytes, keratinocytes and microorganisms in, as well as the turgidity, colour and consistency of, anal sac exudates in clinically normal dogs. DESIGN: Selection criteria were formed based on the absence of clinical signs associated with anal sac disease, and the absence of factors potentially affecting colonic flora. Anal sacs were palpated for turgidity then expressed onto a swab, where colour and consistency were noted. A squash preparation made from any exudate was heat fixed and stained with modified Wright's stain. Eight representative 1000x oil immersion fields from each were examined for leucocytes, erythrocytes, keratinocytes, bacteria and yeast. Results were summarised, and cytological counts grouped into quartiles (minimal, few, moderate, numerous). Due to the multivariate nature of the study and limited subject numbers, further significant statistical analysis could not be performed. RESULTS: Seventeen dogs satisfied the selection criteria. The physical characteristics of the exudate and sac varied, though 31/34 sacs were empty or soft, 22/27 exudates were light or dark brown and 19/27 exudates were a thin liquid. Total leucocyte, keratinocyte and bacilli counts were extremely variable. Yeasts were present in 26/208 microscopic fields examined cytologically. Only 5/208 fields showed numerous cocci. A single instance of intracellular bacteria and a single erythrocyte were noted following examination of all fields. CONCLUSION: In this study, the characteristics of normal anal sacs and their exudate varied but greater than 70% showed similar features. Exudate cytology was highly variable, though yeasts were uncommon, and intracellular cocci and erythrocytes extremely rare.

Macroscopic, cytological and bacteriological evaluation of anal sac content in normal dogs and in dogs with selected dermatological diseases.

Macroscopic and cytological aspects of anal sac content were evaluated in 40 normal dogs and 10 dogs each with pyoderma, Malassezia dermatitis associated with atopic dermatitis and uncomplicated atopic dermatitis. Bacteria isolated from anal sacs were compared with those from abdominal skin and hair in 20 normal dogs and 10 dogs with pyoderma. There was no difference between the groups in anal sac dimension, or in the colour, consistency or presence of granules in their content. Extracellular bacteria were found in higher numbers in diseased animals, whereas intracellular bacteria were observed in 40% of dogs with pyoderma and in only 2.5% of normal dogs. Malassezia spp. were present in 15.7% of dogs, with no difference between groups. Neutrophils were observed in 12.5% of normal dogs, 30% of dogs with Malassezia dermatitis with underlying atopic dermatitis and in 70 and 80% of dogs with pyoderma and uncomplicated atopic dermatitis, respectively. Seven bacterial species were isolated from anal sacs, with no difference between normal dogs and dogs with pyoderma. In five normal animals and in four dogs with pyoderma the same bacterial strains were isolated from anal sacs and from abdominal skin and hair.

Cytology of subcutaneous glandular tissues.

This article deals with the cytologic appearance of various glandular tissues located in the subcutaneous tissues. Normal cytologic features are described. In addition, inflammatory, infectious, neoplastic, and hyperplastic changes are discussed. Most of these features are depicted in the 60+ photomicrographs that are distributed throughout the article. Many of the changes are similar in the glands, and it is usually possible to differentiate the gland of origin based on cytologic appearances. Subcutaneous neoplasms that are not associated with a subcutaneous gland, and lymph node cytology are not covered in this article but are addressed elsewhere.

Cytological and lectin histochemical characterization of secretion production and secretion composition in the tubular glands of the canine anal sacs.

The study reports on secretion production and composition in the tubular glands of the canine anal sacs. For this purpose, light and electron microscopical (TEM, SEM) as well as several histochemical methods for the demonstration of lysosomal acidity, lipofuscin, and complex carbohydrates were used. The glandular tubules exhibited a pseudostratified epithelium with secretory cells of a different shape as related to secretion production activity, and regionally varying amounts of basal cells. Flat, cuboidal or columnar cells with or without apocrine-like protrusions were assembled in one glandular endpiece, although grouping of these cell types often occurred. Active secretory cells were columnar with many cytoplasmic vesicles and a typically merocrine and/or micro-apocrine exocytosis of vesicle contents. Additionally, many lysosomes of different sizes could be found, whereby in aged cells giant secondary lysosomes (autophagolysosomes, about 7 microm in diameter) occupied the major cell part. These giant lysosomes were shed by an apocrine-like process forming a final bottleneck stage of the upper cell part, and consisted of ceroid-type lipofuscin. The general carbohydrate histochemical and the lectin histochemical methods revealed that the secretion produced was composed of strongly concentrated neutral glycoproteins with the following saccharide residues: alpha-D-mannose, beta-D-galactose, beta-N-acetyl-D-glucosamine, alpha-L-fucose and N-acetyl-neuraminic acid (sialic acid); the luminal secretion contained only beta-D-galactose and, especially, N-acetyl-neuraminic acid. This luminal secretion showed a spatially orientated maturation beginning in terminal tubular regions and finishing near the excretory duct, independent of the different secretory cell types. The results obtained demonstrated highly active secretion production, with a regional variation in the glandular tubule, and at least three different modes of secretion by the secretory cells, whereby the shedding of giant lipofuscin granules seems to be very specific. The high amounts of sialic acids in the glycoproteins found may influence the rheological properties of the secretion by their water-binding capacities.