Nathalie Bourgès-Abella

Canine reference intervals for the Sysmex XT-2000iV hematology analyzer

BACKGROUND The laser-based Sysmex XT-2000iV hematology analyzer is increasingly used in veterinary clinical pathology laboratories, and instrument-specific reference intervals for dogs are not available. OBJECTIVE The purpose of this study was to establish canine hematologic reference intervals according to International Federation of Clinical Chemistry and Clinical and Laboratory Standards Institute guidelines using the Sysmex XT-2000iV hematology analyzer. METHODS Blood samples from 132 healthy purebred dogs from France, selected to represent the most prevalent canine breeds in France, were analyzed. Blood smears were scored for platelet (PLT) aggregates. Reference intervals were established using the nonparametric method. PLT and RBC counts obtained by impedance and optical methods were compared. Effects of sex and age on reference intervals were determined. RESULTS The correlation between impedance (I) and optical (O) measurements of RBC and PLT counts was excellent (Pearson r=.99 and .98, respectively); however, there were significant differences between the 2 methods (Students paired t-test, P<.0001). Differences between sexes were not significant except for HCT, PLT-I, and PLT-O. WBC, lymphocyte, and neutrophil counts decreased significantly with age (ANOVA, P<.05). Median eosinophil counts were higher in Brittany Spaniels (1.87 × 10(9) /L), Rottweilers (1.41 × 10(9) /L), and German Shepherd dogs (1.38 × 10(9) /L) than in the overall population (0.9 × 10(9) /L). PLT aggregates were responsible for lower PLT counts by the impedance, but not the optical, method. CONCLUSION Reference intervals for hematologic analytes and indices were determined under controlled preanalytical and analytical conditions for a well-characterized population of dogs according to international recommendations.

Effects of intravenous, low-dose ketamine-diazepam sedation on the results of hematologic, plasma biochemical, and coagulation analyses in cats

OBJECTIVE To evaluate the effects of an IV, low-dose ketamine-diazepam combination used for short-duration chemical restraint on the results of clinicopathologic testing in cats and to assess its practicality and tolerance. DESIGN Prospective case series. ANIMALS 42 client-owned cats of various breeds, ages, and health status. PROCEDURES Blood samples were obtained just prior to and just after IV injection of ketamine chlorhydrate (10 mg) and diazepam (0.5 mg). A CBC, plasma biochemistry panel, and coagulation profile were performed on each sample (ie, before and after chemical restraint). Practicality of the procedure was assessed, and cats were monitored for immediate and delayed effects. RESULTS Significant changes were observed for most of the analytes tested. However, the magnitude of the observed changes was notably low and likely not of clinical relevance. The chemical-restraint procedure appeared effective, safe, and well tolerated. CONCLUSIONS AND CLINICAL RELEVANCE The IV, low-dose ketamine-diazepam combination used for short-duration chemical restraint in the present study may be suitable to assist physical restraint for blood sampling for assessment of hematologic, serum biochemical, and coagulation parameters in cats.

Histopathologic features of canine distichiasis.

OBJECTIVE To describe the histologic features of canine distichiasis using excised tarsoconjunctival specimens that included roots of distichiatic cilia. PROCEDURES The study group included 21 strips of cilia-bearing tarsoconjunctiva resected from 20 dogs with distichiasis. Eyelid tissue specimens were also collected from 11 euthanized dogs without distichiasis to serve as controls. All flat mount preparations were processed for histologic examination, and serial sections were stained with hematoxylin-eosin (H&E). A total of 157 slides were examined for the study group to describe the follicles and path of the distichiatic hairs and determine their potential connection with the tarsal glands. A total of 82 slides were examined for the control group. RESULTS In 19 of the 20 dogs with distichiasis, serial sections of the specimens identified anatomic segments of hair follicles located abnormally in the eyelid tarsus and associated with the aberrant cilia. They appeared as hair bulbs adjacent to tarsal glands, middle portions of hair follicles located between sebaceous lobules, and single or multiple hair shafts present within the sebaceous duct. The tarsal glands in the cilia-bearing tarsoconjunctiva were not different from those of the controls, in which no distichiatic hair bulbs or shafts were observed. CONCLUSIONS These results demonstrate that adventitious cilia are not associated with histologic changes of the tarsal glands, and appear to arise from ectopic hair follicles present in the tarsus. Canine distichiasis may result from anomalous regulation of morphogenesis of hair follicles in the mesenchymal tissue of the tarsal plate.

Time-of-flight secondary ion mass spectrometry imaging demonstrates the specific localization of deca-bromo-diphenyl-ether residues in the ovaries and adrenal glands of exposed rats

Deca-bromo-diphenyl ether (DBDE) is one of the most efficient brominated flame retardant (BFR) available on the market. We recently demonstrated that when administered to female rat by oral route, DBDE is efficiently absorbed, with the highest residual concentrations found in two endocrine glands, namely the adrenal glands and the ovaries. Tinie-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging, a technique usually used for the study of endogenous compounds, was applied for the first time to a persistent organic pollutant, allowing to detect and to precisely localize DBDE residues in these two target tissues. The detection of the bromide ion (81Br isotope) by TOF-SIMS mass spectrometry imaging allowed us to demonstrate a marked cortical tropism of DBDE residues for the adrenal glands in female rats dosed per os 2 mg · kg−1 DBDE, daily, over 96 h. In ovaries, DBDE residues were found to be concentrated in spots corresponding to part of the corpora lutea. Hepatic residues of DBDE were found to be homogeneously distributed. Due to the intrinsic toxicity of DBDE, its accumulation in the adrenal glands and the ovaries may be connected to the mechanisms of actions by which DBDE could trigger endocrine disruption in mammals.

Changes in hematology measurements in healthy and diseased dog blood stored at room temperature for 24 and 48 hours using the XT‐2000iV analyzer

BACKGROUND Changes in canine hematology measurements may occur when analyses are delayed due to shipment of specimens to a laboratory. OBJECTIVE The purpose of this study was to report changes in hematologic variables in healthy and diseased canine blood measured with a Sysmex XT-2000iV during storage at room temperature for 24 and 48 hours. METHODS EDTA-K3 blood samples from 42 healthy and diseased dogs were measured on a Sysmex XT-2000iV analyzer within one hour of sampling, and after storage for 24 and 48 hours at room temperature in the dark. RESULTS Storage caused little or no change in RBC count, HGB concentration and MCH, while there was a moderate increase in HCT, MCV and reticulocytes count, and a moderate decrease in MCHC. Decreased platelet counts by impedance (PLT-I) and optical (PLT-O) measurements were associated with increased mean platelet volume (MPV), platelet-large cell ratio (P-LCR) and platelet distribution width (PDW), including a right shift in the platelet histogram and a dispersion of the platelet dot plot on the scattergram. The total and differential WBC count remained stable except for decreased monocyte counts. In the scatterplots, monocytes shifted into the lymphocyte population after 24 hours, and neutrophil population shifted to the right appearing in the eosinophil gate at 48 hours of storage. The disease status had only a small effect on storage-induced changes, and observed changes had no consequences for clinical decisions. CONCLUSIONS Blood storage at room temperature was accompanied by moderate variations in some hematologic variables, awareness of which helps in avoiding misinterpretations.

Feline reference intervals for the Sysmex XT-2000iV and the ProCyte DX haematology analysers in EDTA and CTAD blood specimens

Laser-based haematology analysers are routinely used in veterinary clinical pathology laboratories, and are available to practitioners. However, feline haematological reference intervals (RIs) determined according to international recommendations are, to our knowledge, not available. Furthermore, platelet count RI is difficult to establish in cats because of the frequent occurrence of platelet aggregation in blood specimens. The purpose of this study was to establish feline haematological RIs with the Sysmex XT-2000iV and ProCyte DX analysers, in ethylenediamine tetra-acetic acid (EDTA) and in citrate, theophylline, adenosine and dipyridamole (CTAD), which is a combination of anticoagulants limiting platelet aggregation. Blood specimens from 120 healthy cats were analysed in duplicate, and the degree of platelet aggregation was assessed on blood smears. After exclusion of inadequate specimens, 81 sets of results (from 44 males and 37 females, aged from 6 to 116 months) were available for the determination of RIs by the non-parametric method. The effects of the anticoagulant, analyser and aggregation score were assessed. When the aggregation effect was significant, the RIs were determined using the subgroup of blood specimens with no or little aggregation. The effects of sex, age and weight were also investigated, but were moderate. The different RIs obtained with the Sysmex XT-2000iV and ProCyte DX analysers, and the two anticoagulants, were very similar to previous RIs established in EDTA with the ADVIA 120, another laser-based analyser, except for the platelet count in CTAD specimens. Its lower reference limit was higher in CTAD vs EDTA specimens, which confirms the interest in this anticoagulant in cats.

Changes in haematology measurements with the Sysmex XT-2000iV during storage of feline blood sampled in EDTA or EDTA plus CTAD

In veterinary medicine a complete blood cell count (CBC) cannot always be performed within 24 h as usually recommended, particularly for specimens shipped to a reference laboratory. This raises the question of the stability of the variables, especially in ethylenediamine tetra-acetic acid (EDTA) feline blood specimens, known to be prone to in vitro platelet aggregation. Citrate, theophylline, adenosine and dipyridamole (CTAD) has been reported to limit platelet aggregation in feline blood specimens. The aim of this study was to measure the stability of the haematological variables and the platelet aggregation score in EDTA and EDTA plus CTAD (EDCT) feline blood specimens during 48 h of storage at room temperature. Forty-six feline EDTA and EDCT blood specimens were analysed with a Sysmex XT-2000iV analyser, and the platelet count and score of platelet aggregation were estimated immediately and after 24 and 48 h of storage. A significant increase in mean corpuscular volume, haematocrit, reticulocyte and eosinophil counts, and a significant decrease in mean corpuscular haemoglobin concentration and monocyte count were observed. Haemoglobin, mean corpuscular haemoglobin, and red blood cell, white blood cell, neutrophil and lymphocyte counts remained stable. Changes in reticulocyte indexes with time (low fluorescence ratio, medium fluorescence ratio, high fluorescence ratio and immature reticulocyte fraction) were not significant. Changes were generally more pronounced in EDTA than in EDCT. Platelet aggregation decreased markedly in initially highly aggregated EDTA specimens, and increased slightly in initially non- or mildly-aggregated EDTA or EDCT specimens. Platelet counts increased and decreased, or remained stable, respectively. CTAD can reduce storage-induced changes of the haematological variables in feline samples, thus improving the reliability of a CBC and limiting clinical misinterpretations.

Validation of the Medonic CA620/530 Vet 20-μ1 Microcapillary Sampler System for Hematology Testing of Feline Blood

The aim of the current study was to compare feline hematologic variables in blood collected in microcapillary tubes (20 μl) and conventional blood tubes with the Medonic CA620/530 Vet in-house hematologic analyzer. A comparison of results obtained in 60 cats presented at the clinics of the veterinary school showed that the correlations between the 2 methods were 0.97 for white blood cell, 0.95 for red blood cell, and 0.93 for platelet counts; 0.92 for hemoglobin concentration; and 0.99 for mean corpuscular volume. No clinically relevant differences between the 2 blood sampling techniques were observed for any variable, which suggests that both techniques are interchangeable in cats. Moreover, microcapillary tubes would allow easier repeated sampling in the same cat and would likely be useful in other small species.

Evaluation of CTAD (citrate–theophylline–adenosine–dipyridamole) as a universal anticoagulant in dogs

CTAD (citrate–theophylline–adenosine–dipyridamole) has been shown to be an almost universal anticoagulant in human and feline medicine, allowing most hematology, coagulation, and biochemical analyses. Forty canine blood specimens were collected in CTAD, EDTA, heparin, and citrate for hematology, biochemistry, and coagulation analyses. CTAD partially limited platelet aggregation observed in EDTA blood smears. CTAD specimens gave similar and well-correlated results for most variables of a complete blood cell count, except for mean corpuscular volume, which was moderately higher, and mean corpuscular hemoglobin concentration, which was moderately lower in CTAD than in EDTA; reticulocyte and platelet indexes were poorly correlated. CTAD plasma gave similar results to citrate for fibrinogen, antithrombin, and D-dimers, and relatively similar results for prothrombin time, but activated partial thromboplastin time was poorly correlated. Triglycerides, cholesterol, glucose, total proteins, phosphate, iron, alanine aminotransferase, γ-glutamyl transferase, and lipase were similar and well correlated in CTAD and heparin plasmas. Urea, creatinine, albumin, alkaline phosphatase, amylase, and aspartate aminotransferase showed moderate-to-marked bias, but these variables could be measured in CTAD plasma if new reference intervals were determined. Creatine kinase activity, potassium, chloride, and total carbon dioxide measurements are not recommended in CTAD plasma. CTAD is a prospective candidate as an almost universal anticoagulant for routine hematology, some plasma coagulation, and many biochemistry variables in dogs. Definitive recommendations will require study of abnormal canine blood specimens.