Fecal Cytology Research Articles

A RETROSPECTIVE REVIEW OF THE CLINICAL UTILITY OF FECAL BACTERIAL ENTERIC PATHOGEN CULTURES IN MAMMALS WITHIN A ZOOLOGICAL COLLECTION AND THE USE OF FECAL CYTOLOGY FOR OPTIMIZATION OF DIAGNOSTIC TESTING.

To determine the diagnostic value of fecal bacterial enteric pathogen cultures (FBEPC) as part of routine preventive medicine protocols in terrestrial mammals housed in a zoological collection, this study investigated the clinical utility of FBEPC results in context of subsequent clinical actions and how its use was rationalized after adjunct use of fecal cytology as a first-line diagnostic tool. Retrospective results (n = 692) that included a routine FBEPC panel of a commercial diagnostic laboratory, including Aeromonas, Salmonella, Campylobacter, Plesiomonas, Shigella, Yersinia, and Edwardsiella, of 417 mammals were organized into preventive (P; n = 485), diagnostic (D; n = 177), or recheck (R; n = 30) samples; for P and D samples, findings were assigned a "clinical significance factor" of 1 to 5 according to culture results and subsequent clinical actions. A score of 3 or higher indicated positive growth of potentially pathogenic bacterial organisms, of which there were 50 FBEPC (P n = 27, D n = 20, R n = 3). The difference in mean clinical significance factor for P versus D samples was significant. Aeromonas spp. were most frequently isolated (n = 32), followed by Salmonella spp. (n = 8) and Plesiomonas shigelloides (n = 8), then Campylobacter spp. (n = 5). There was no growth of Yersinia enterocolitica, Shigella spp., or Edwardsiella spp. In the absence of clinical evidence of gastrointestinal disease, treatment was initiated in only two cases with isolated Campylobacter spp. Implementation of fecal cytology as an initial step in fecal evaluation resulted in a prompt, substantial reduction in number of ordered FBEPC (mean n = 12/month before and n = 5/month after implementation). The findings in this study suggest that FBEPC for these bacterial species has limited value as a screening tool in preventive medicine protocols for the mammalian orders best represented in this study. The use of fecal cytology led to a more targeted and cost-effective use of FBEPC. Fecal cytology as an initial step in preventative and diagnostic testing protocols is recommended.

COMPARISON OF FECAL CYTOLOGY AND PRESENCE OF CLOSTRIDIUM PERFRINGENS ENTEROTOXIN IN CAPTIVE BLACK-FOOTED FERRETS (MUSTELA NIGRIPES) BASED ON DIET AND FECAL QUALITY.

The black-footed ferret (Mustela nigripes) is an endangered mustelid native to North America. Gastroenteritis is a documented cause of morbidity and mortality in managed individuals, particularly by infectious agents. Fecal cytology is an inexpensive and rapid test that can help guide clinical management strategies for animals with enteritis; however, normal parameters have not been established in black-footed ferrets. The objective of this study was to characterize fecal cytological findings of 50 fecal samples from 18 black-footed ferrets that received two different diet types (ground meat versus whole prey) and that were visibly judged to be normal or abnormal. This study also tested for the presence of Clostridium perfringens enterotoxin by enzyme-linked immunosorbent assay in all abnormal and a subset of normal fecal samples. Significantly higher spore-forming bacteria and yeast prevalence were present in normal feces from individuals following the meat-based compared with the whole-prey diet. Samples from individuals with abnormal feces had significantly more spore-forming bacteria than normal feces, regardless of diet. Normal feces had higher diplococci and spore-forming bacteria compared with domestic canine and feline standards. A single abnormal fecal sample was positive for enterotoxin and originated from the only animal requiring treatment. Results indicate that low numbers of spore-forming bacteria can be found in fecal samples from clinically normal black-footed ferrets. Fecal cytology shows significantly increased spore-formers in clinically abnormal ferrets and in clinically normal ferrets following a ground meat-based diet.

From macrocosm to microcosm: The art and beauty of plant material and diatoms in sea urchin fecal cytology specimens.

From macrocosm to microcosm: The art and beauty of plant material and diatoms in sea urchin fecal cytology specimens.

SERUM COBALAMIN AND FOLATE CONCENTRATIONS AS INDICATORS OF GASTROINTESTINAL DISEASE IN KILLER WHALES ( ORCINUS ORCA).

Cobalamin and folate are water-soluble vitamins that are useful indicators of chronic gastrointestinal (GI) function in humans and some animal species. Serum cobalamin and folate concentrations in an ex situ population of killer whales ( Orcinus orca) were measured and factors that may affect their serum concentrations were identified. Serum samples ( n = 104) were analyzed from killer whales ( n = 10) both while clinically healthy and during periods of clinical GI disease as defined by clinical signs and fecal cytology. To characterize serum cobalamin and folate concentrations in clinically healthy animals, a mixed-model regression was used, with cobalamin and folate both significantly affected by weight (cobalamin: P < 0.0001, folate: P = 0.006) and season (cobalamin: P < 0.0001, folate: P < 0.0001). The marginal mean concentrations for cobalamin and folate across weight and season were 742 ± 53.6 ng/L and 30.2 ± 2.6 μg/L, respectively. The predicted 95% confidence intervals (CI) for these analytes were then compared with samples collected during periods of GI disease. Across individuals, 22% (2/9) of the folate and 80% (8/10) of the cobalamin samples from the animals with GI disease fell outside the 95% CI for the population. When comparing samples within an individual, a similar pattern presented, with 100% of cobalamin of the observed abnormal samples reduced compared to healthy animal concentration variability. The same was not true for folate. These results suggest that serum concentrations of cobalamin and folate may be useful minimally invasive markers to identify GI disease in killer whales, especially when values are compared within an individual.

Optimization of fecal cytology in the dog: comparison of three sampling methods.

Dry-mount fecal cytology (FC) is a component of the diagnostic evaluation of gastrointestinal diseases. There is limited information on the possible effect of the sampling method on the cytologic findings of healthy dogs or dogs admitted with diarrhea. We aimed to: (1) establish sampling method-specific expected values of selected cytologic parameters (isolated or clustered epithelial cells, neutrophils, lymphocytes, macrophages, spore-forming rods) in clinically healthy dogs; (2) investigate if the detection of cytologic abnormalities differs among methods in dogs admitted with diarrhea; and (3) investigate if there is any association between FC abnormalities and the anatomic origin (small- or large-bowel diarrhea) or the chronicity of diarrhea. Sampling with digital examination (DE), rectal scraping (RS), and rectal lavage (RL) was prospectively assessed in 37 healthy and 34 diarrheic dogs. The median numbers of isolated ( p = 0.000) or clustered ( p = 0.002) epithelial cells, and of lymphocytes ( p = 0.000), differed among the 3 methods in healthy dogs. In the diarrheic dogs, the RL method was the least sensitive in detecting neutrophils, and isolated or clustered epithelial cells. Cytologic abnormalities were not associated with the origin or the chronicity of diarrhea. Sampling methods differed in their sensitivity to detect abnormalities in FC; DE or RS may be of higher sensitivity compared to RL. Anatomic origin or chronicity of diarrhea do not seem to affect the detection of cytologic abnormalities.

Prevalence and pathology of lungworm infection in bottlenose dolphins Tursiops truncatus from southwest Florida

Parasitism of the respiratory system is a relatively common finding in stranded cetaceans; however, no systematic investigations regarding the severity, distribution, and clinical consequences of these infections in bottlenose dolphins Tursiops truncatus have been conducted previously. The present study determined the prevalence of lungworm infections in dead stranded (n=22) and live bottlenose dolphins (n=44) from southwestern Florida, USA, during the period from 2003 to 2005. Dead stranded bottlenose dolphins were necropsied and lungs were examined visually, by palpation, and histologically for lesions consistent with verminous pneumonia. When present, nematodes were counted, measured, and identified to species based upon their morphology. Dolphin feces and blowhole swabs were collected and examined for nematode larvae. Lungworm prevalence was 77% in dead animals (n=22). The lesions in most cases were mild, chronic, and not the primary cause of death. Only 13% of dead animals examined had patent infections, with larvae present in blowhole and fecal cytology, and only 18% of animals had intact worms present at necropsy, with a geometric mean intensity of infection of 22.6 worms animal(-1). Intact worms were identified as either Halocercus lagenorhynchi or Skrjabinalius cryptocephalus. The highest prevalence of active infections was found in neonates and calves, including 1 stillborn calf. For free-ranging animals, all blowhole swabs (n=44) were negative, and fecal cytology (n=22) showed a 3% prevalence of patent infection. Findings from the present study support the theory that bottlenose dolphins can be infected transplacentally by lungworms. The impact that such infections may have on neonatal survival is unknown; however, these infections could increase neonatal mortality.

Diagnosis of systemic cryptococcosis by fecal cytology in a dog

A 3-year-old Boxer was presented with progressive diarrhea, vomiting, and lethargy of 5-months duration. The dog had watery black feces, a mature neutrophilia, and microcytic anemia. Cytologic evaluation of a direct fecal smear stained with Wright's-Giemsa revealed numerous encapsulated, narrow-based, budding organisms consistent with Cryptococcus sp. Pyogranulomatous inflammation and Cryptococcus organisms also were observed in ultrasound-guided fine-needle aspirates of the small intestine and mesenteric lymph nodes, and in histologic sections of colonic biopsies obtained by endoscopy. Multifocal chorioretinitis by fundic examination was consistent with systemic mycosis, and the reciprocal antigen titer (1600) on a cryptococcal antigen latex agglutination test for Cryptococcus neoformans was markedly increased. Using immunohistochemistry, the organism was identified further as C neoformans var. grubii (C neoformans var. neoformans serotype A). After 3 weeks of antifungal treatment, ultrasound examination revealed urinary bladder wall thickening, and Cryptococcus organisms were found in a urine sediment preparation. After 4 months of treatment, the dog was clinically normal and had no abnormal findings on CBC, serum biochemistry, urinalysis, or fecal cytology; however, the antigen titer remained unchanged, mesenteric lymphadenomegaly and jejunal wall thickening were still evident, and cytologic evaluation of fine-needles aspirates of the jejunal wall revealed budding Cryptococcus organisms. Intestinal involvement in dogs with cryptococcosis is rare, and diagnosis by fecal cytology has not been documented previously.

An Epidemiological Survey of Clostridium perfringens-Associated Enterotoxemia at an Army Veterinary Treatment Facility

The purpose of this study was to determine the incidence of Clostridium perfringens-associated vomiting and diarrhea in canine and feline patients at the Okinawa Branch Veterinary Service and to establish a relationship between dietary indiscretion and the presence of clostridial enterotoxemia. Stool samples were obtained from 38 control animals and 44 animals with vomiting and diarrhea during a 3-month period. For each sample, fecal cytology were examined for the presence of C. perfringens, white blood cells, and red blood cells. A survey was also completed by the animal's owner, which provided the researcher with information on the owner's pet feeding practices. After the data were analyzed, 27% of animals with vomiting and diarrhea were found to have C. perfringens upon examination of their fecal samples (p < 0.05), compared with 11% for control animals. Results of our survey revealed that when owners were questioned regarding their feeding practices, 45% of the animals with C. perfringens-positive fecal samples and with clinical signs of vomiting and/or diarrhea had an episode of dietary indiscretion soon before the illness (p < 0.05). Therefore, we conclude that C. perfringens is an important cause of vomiting and diarrhea in our patient population and that a causal relationship may exist between dietary indiscretion and C. perfringens-associated intestinal disease.

Clostridium tertium Infection in a Rainbow Lorikeet (Trichoglossus haematodus haematodus) with Enteritis

An adult female rainbow lorikeet (Trichoglossus haematodus haematodus) was presented with an acute onset of vomiting and melena. Fecal cytology and fecal Gram stain confirmed the presence of erythrocytes and bacteria morphologically similar to clostridia. Clostridium tertium was cultured from the feces. Leukocytosis with moderate absolute heteropenia, absolute lymphocytosis, and toxic immature heterophils was observed on the complete blood count. Plasma biochemistry analysis included mild hyperuricemia and metabolic alkalosis. The most significant radiographic abnormalities included proventricular filling defects, intestinal dilatation, and gas accumulation in the gastrointestinal tract. All radiographic changes were believed to be secondary to bacterial infection. Clostridial enteritis was tentatively diagnosed and successfully treated with antibiotics and supportive care. Clostridium tertium infection was hypothesized to have originated from the combination of a contaminated water source, a high carbohydrate diet, and a lack of adequate sanitation. No further clinical problem occurred after implementation of husbandry recommendations.