Accuracy evaluation of two portable blood glucose meters in feline patients using whole blood samples / Avaliação da acurácia de dois glicosímetros portáteis em amostras de sangue total de pacientes felinos

ABSTRACT: Using portable blood glucose meters (PBGMs) to measure blood glucose (BG) concentration is a common procedure in veterinary practice. Our objective was to evaluate the analytical and clinical accuracy of a human PBGM (Accu-Chek Performa®), (AC) and a veterinary PBGM (GlucoCalea®), (GC) in feline patients. Central venous blood samples were collected from 48 cats at a Brazilian Veterinary teaching hospital. Two devices from each model were used and compared to a reference method (RM). Analytical accuracy was assessed according to ISO 15197:2013 requirements for human PBGMs. Data were compared using Wilcoxon's nonparametric test and represented by Bland-Altman plots. Hematocrit's effect on BG measurements was evaluated by the Spearman correlation coefficient. Clinical accuracy was determined using error grid analysis (EGA). Values of BG were significantly higher in all PBGMs compared to the RM. Although ISO's analytical accuracy requirements could not be met by any of the devices, AC meters were more accurate than GC meters. All AC measurements - but not GC ones - were within zones A and B of the EGA, meeting ISO requirements for clinical accuracy. Significant hematocrit interference was observed in all devices. Therefore, AC showed greater accuracy compared to GC using feline whole blood samples.

RESUMO: O uso de glicosímetros portáteis (GPs) para aferição da glicemia é um procedimento comum na rotina clínica veterinária. O objetivo deste trabalho é avaliar a acurácia analítica e clínica de um GP humano (Accu-Chek Performa®), (AC) e um GP veterinário (GlucoCalea®), (GC) em gatos. Amostras de sangue venoso central foram coletadas de 48 gatos atendidos em um hospital veterinário-escola no Brasil. Foram utilizados dois GPs de cada modelo e comparados a um método de referência (MR). A acurácia analítica foi avaliada de acordo com os requisitos estipulados pela ISO 15197:2013 para GPs de uso humano. Os dados foram comparados pelo teste não-paramétrico de Wilcoxon e representados em gráficos de Bland-Altman. O efeito do hematócrito sobre os valores de glicemia foi avaliado pelo coeficiente de correlação de Spearman. A acurácia clínica foi avaliada pela análise da grade de erros (AGE). Em comparação com o MR, os valores de glicemia foram maiores em todos os GPs avaliados. Nenhum deles atendeu aos requisitos da ISO quanto à acurácia analítica, mas o AC mostrou-se mais acurado que o GC. Todos os valores de glicemia obtidos pelos GPs humanos - mas não pelos GPs veterinários - estiveram dentro das zonas A e B da AGE, demonstrando acurácia clínica de acordo com as exigências da ISO. A interferência do hematócrito da amostra mostrou-se significativa em todos os aparelhos testados. Portanto, o AC apresentou maior acurácia quando comparado ao GC em amostras de sangue total em felinos.

Accuracy evaluation of two portable blood glucose meters in feline patients using whole blood samples / Avaliação da acurácia de dois glicosímetros portáteis em amostras de sangue total de pacientes felinos

Using portable blood glucose meters (PBGMs) to measure blood glucose (BG) concentration is a common procedure in veterinary practice. Our objective was to evaluate the analytical and clinical accuracy of a human PBGM (Accu-Chek Performa®), (AC) and a veterinary PBGM (GlucoCalea®), (GC) in feline patients. Central venous blood samples were collected from 48 cats at a Brazilian Veterinary teaching hospital. Two devices from each model were used and compared to a reference method (RM). Analytical accuracy was assessed according to ISO 15197:2013 requirements for human PBGMs. Data were compared using Wilcoxon's nonparametric test and represented by Bland-Altman plots. Hematocrit's effect on BG measurements was evaluated by the Spearman correlation coefficient. Clinical accuracy was determined using error grid analysis (EGA). Values of BG were significantly higher in all PBGMs compared to the RM. Although ISO's analytical accuracy requirements could not be met by any of the devices, AC meters were more accurate than GC meters. All AC measurements - but not GC ones - were within zones A and B of the EGA, meeting ISO requirements for clinical accuracy. Significant hematocrit interference was observed in all devices. Therefore, AC showed greater accuracy compared to GC using feline whole blood samples.

O uso de glicosímetros portáteis (GPs) para aferição da glicemia é um procedimento comum na rotina clínica veterinária. O objetivo deste trabalho é avaliar a acurácia analítica e clínica de um GP humano (Accu-Chek Performa®), (AC) e um GP veterinário (GlucoCalea®), (GC) em gatos. Amostras de sangue venoso central foram coletadas de 48 gatos atendidos em um hospital veterinário-escola no Brasil. Foram utilizados dois GPs de cada modelo e comparados a um método de referência (MR). A acurácia analítica foi avaliada de acordo com os requisitos estipulados pela ISO 15197:2013 para GPs de uso humano. Os dados foram comparados pelo teste não-paramétrico de Wilcoxon e representados em gráficos de Bland-Altman. O efeito do hematócrito sobre os valores de glicemia foi avaliado pelo coeficiente de correlação de Spearman. A acurácia clínica foi avaliada pela análise da grade de erros (AGE). Em comparação com o MR, os valores de glicemia foram maiores em todos os GPs avaliados. Nenhum deles atendeu aos requisitos da ISO quanto à acurácia analítica, mas o AC mostrou-se mais acurado que o GC. Todos os valores de glicemia obtidos pelos GPs humanos - mas não pelos GPs veterinários - estiveram dentro das zonas A e B da AGE, demonstrando acurácia clínica de acordo com as exigências da ISO. A interferência do hematócrito da amostra mostrou-se significativa em todos os aparelhos testados. Portanto, o AC apresentou maior acurácia quando comparado ao GC em amostras de sangue total em felinos.

Canine endogenous adrenocorticotrophic hormone preanalytical stability after sample shipping in dry ice or recyclable ice bars / Estabilidade pré-analítica do hormônio adrenocorticotrófico endógeno canino após remessa de amostras em gelo seco ou com barras de gelo reciclável

Endogenous adrenocorticotrophic hormone (eACTH) measurement is useful in hypercortisolism and hypoadrenocorticism investigation; however, since the hormone is highly unstable, blood samples require proper processing and storage, as well as shipping is often a step limiting since few laboratories offer this assay in Brazil. The aim of this note was to compare overnight dog´s eACTH preanalytical stability when frozen samples were shipped in dry ice (DI), or with recyclable ice bars (RIB). A total of 56 paired samples for eACTH measurement were analyzed. Blood samples were properly handled, plasma aliquots transferred into plastic microtubes, and stored at -80ºC. The fifty-six paired samples were overnight shipped in two thermic isolated boxes with DI or involved by RIB. Despite there was a high correlation between results from both shipping methods (r Spearman = 0.958, P<0.001), the Wilcoxon matched-pairs rank test showed that the shipping method may influence results (P<0.001). However, this difference does not affect results interpretation. By this way, when DI shipping was not possible, RIB shipping may represent a risk to eACTH preanalytical stability.(AU)

A mensuração do hormônio adrenocorticotrófico endógeno (ACTHe) é útil na investigação do hipercortisolismo e hipoadrenocorticismo. No entanto, como o hormônio é bastante instável, as amostras de sangue necessitam um manejo adequado no processamento e armazenamento, assim como o envio para laboratórios pode ser um passo limitante, uma vez que poucos laboratórios oferecem este ensaio no Brasil. O objetivo deste trabalho foi comparar a estabilidade pré-analítica do ACTHe durante longo período de envio de amostras congeladas em gelo seco (GS), ou com barras de gelo reciclável (BGR). Um total de 56 amostras pareadas para mensuração de ACTHe foram analisadas. As amostras de sangue foram adequadamente manejadas, sendo o plasma transferido para micro tubos plásticos estocados a -80ºC. Os 56 pares de amostras foram enviados à tarde para chegada ao laboratório na manhã seguinte em dois isopores, um com GS e outro com BGR. Apesar de uma alta correlação entre os resultados dos diferentes métodos de envio (r Spearman = 0,958, P<0,001), o teste de Wilcoxon para amostras pareadas mostrou que o método de envio influencia os resultados P<0,001). Apesar desta diferença, os resultados não afetaram a interpretação dos resultados. Desta forma, quando o envio em gelo seco não for possível, o envio das amostras com barras de gelo reciclável pode representar um risco à estabilidade pré-analítica do ACTHe.(AU)

Congenital secondary hypothyroidism evidences in a dog

Background: Deficiency of thyroid hormones thyroxine (T4) and triiodothyronine (T3) results in multisystemic disease described as hypothyroidism (HpoT). Secondary HpoT is defined by TSH decreased production and, therefore, thyroid hormones. This condition is rare in dogs, accounting for less than 5% of cases. The objective of this report is to describe evidence of congenital secondary hypothyroidism in a mongrel dog and therapeutic response obtained.Case: A 3-year-old neutered male mongrel dog was brought to the veterinarian with a history of overweight without polyphagia, associated with discrete alopecia, poor quality skin and hair coat, lethargy and evident exercise intolerance. Physical examination revealed a body condition score of seven (1 to 9 scale), disqueratosis, pyoderma, ventral cervical alopecia, hair thinning on the posterior surface of the pelvic limbs and nonpalpable thyroid. A body conformation characterized by disproportionate dwarfism was observed. Owners provided a former patient´s X-ray (18 months of age), showing growth plate non-closure in vertebral bodies. Results of a complete blood count (CBC) and serum biochemical profile were within normal limits except for elevated fructosamine (459 µmol/L; reference range: 170-338 µmol/L) and total cholesterol (558 mg/dL; reference range: 135-270 mg/dL). Analyses of the hormone profile showed decreased levels of canine thyroid-stimulating hormone (cTSH) 0.03 ng/mL (reference range: 0.05-0.5 ng/mL), free thyroxine by equilibrium dialysis (fdT4) 0.57 ng/dL (reference range: 0.8-3.0 ng/dL), and total thyroxine (tT4) 5.1 ng/mL (reference range: 15-30 ng/mL). A distal forelimb X-ray was performed and showed opened epiphyseal growth plates from radius and ulnar bones. The patient was discharged with sodium levothyroxine (20 µg/kg PO q 24 hr) until re-evaluation...

Congenital secondary hypothyroidism evidences in a dog

Background: Deficiency of thyroid hormones thyroxine (T4) and triiodothyronine (T3) results in multisystemic disease described as hypothyroidism (HpoT). Secondary HpoT is defined by TSH decreased production and, therefore, thyroid hormones. This condition is rare in dogs, accounting for less than 5% of cases. The objective of this report is to describe evidence of congenital secondary hypothyroidism in a mongrel dog and therapeutic response obtained.Case: A 3-year-old neutered male mongrel dog was brought to the veterinarian with a history of overweight without polyphagia, associated with discrete alopecia, poor quality skin and hair coat, lethargy and evident exercise intolerance. Physical examination revealed a body condition score of seven (1 to 9 scale), disqueratosis, pyoderma, ventral cervical alopecia, hair thinning on the posterior surface of the pelvic limbs and nonpalpable thyroid. A body conformation characterized by disproportionate dwarfism was observed. Owners provided a former patient´s X-ray (18 months of age), showing growth plate non-closure in vertebral bodies. Results of a complete blood count (CBC) and serum biochemical profile were within normal limits except for elevated fructosamine (459 µmol/L; reference range: 170-338 µmol/L) and total cholesterol (558 mg/dL; reference range: 135-270 mg/dL). Analyses of the hormone profile showed decreased levels of canine thyroid-stimulating hormone (cTSH) 0.03 ng/mL (reference range: 0.05-0.5 ng/mL), free thyroxine by equilibrium dialysis (fdT4) 0.57 ng/dL (reference range: 0.8-3.0 ng/dL), and total thyroxine (tT4) 5.1 ng/mL (reference range: 15-30 ng/mL). A distal forelimb X-ray was performed and showed opened epiphyseal growth plates from radius and ulnar bones. The patient was discharged with sodium levothyroxine (20 µg/kg PO q 24 hr) until re-evaluation...(AU)

Frequency of endocrinopathies and characteristics of affected dogs and cats in Southern Brazil (2004-2014)

Background: The increase in the life expectancy of dogs and cats in recent decades has heightened the incidence of aging-associated diseases. Among such diseases, endocrinopathies, such as obesity, stand out. In addition, there exists a lack of professionals with expertise in this area. Therefore, proper knowledge of the characteristics of patients affected by endocrinopathies as well as the frequency of these diseases aid in the recognition of endocrine syndromes in the general population. Thus, the aim of this study was to conduct a retrospective analysis of medical charts of dogs and cats compiled by a Division of Endocrinology in southern Brazil during a 10-year period. Materials, Methods & Results: An epidemiological survey of the medical charts of 1,400 dogs and cats compiled by a Division of Endocrinology between 2004 and 2014 was performed. The diagnostic data based on laboratory and hormone tests and on ultrasound scans were used as gold standard. The data were tabulated using Excel for Windows for the stratified analysis of the diagnoses. The major diseases (93.4% of the cases) detected in dogs were hyperadrenocorticism (37%), diabetes mellitus (22%), hypothyroidism (11%), and overweight/obesity (8%), whereas the main diseases (6.6% of the cases) detected in cats were diabetes mellitus (42%) and hyperthyroidism (23%). Some rare and uncommon diseases were diagnosed [...](AU)

Frequency of endocrinopathies and characteristics of affected dogs and cats in Southern Brazil (2004-2014)

Background: The increase in the life expectancy of dogs and cats in recent decades has heightened the incidence of aging-associated diseases. Among such diseases, endocrinopathies, such as obesity, stand out. In addition, there exists a lack of professionals with expertise in this area. Therefore, proper knowledge of the characteristics of patients affected by endocrinopathies as well as the frequency of these diseases aid in the recognition of endocrine syndromes in the general population. Thus, the aim of this study was to conduct a retrospective analysis of medical charts of dogs and cats compiled by a Division of Endocrinology in southern Brazil during a 10-year period. Materials, Methods & Results: An epidemiological survey of the medical charts of 1,400 dogs and cats compiled by a Division of Endocrinology between 2004 and 2014 was performed. The diagnostic data based on laboratory and hormone tests and on ultrasound scans were used as gold standard. The data were tabulated using Excel for Windows for the stratified analysis of the diagnoses. The major diseases (93.4% of the cases) detected in dogs were hyperadrenocorticism (37%), diabetes mellitus (22%), hypothyroidism (11%), and overweight/obesity (8%), whereas the main diseases (6.6% of the cases) detected in cats were diabetes mellitus (42%) and hyperthyroidism (23%). Some rare and uncommon diseases were diagnosed [...]