Evaluation of low sodium:potassium ratios in dogs

Mineral and heavy metal content in dry dog foods with different main animal components

Dog caregivers, mainly for economic reasons and easy availability, choose dry, over the counter diets (OTC). The mineral composition of OTC foods depends primarily on the components used in the production of the pet food. Regardless of the main component of the food, it must meet the recommended minimum mineral content, established by nutritional guidelines. Therefore, the aim of this study was to determine the mineral (Ca, K, Mg, Na, Fe, Mn, Zn, Cu, Mo) and heavy metal content (Pb, Co, Cd, Cr, Ni) using the methods of colorimetry and mass spectrometry, of OTC dry dog foods and to compare with the FEDIAF and AAFCO nutritional guidelines. Dry foods pose no risk to dogs in terms of heavy metal content. The worst results in terms of mineral content were obtained in mixed foods, therefore it is worth considering feeding the dog a mono-protein food. The PCA analysis disproved our hypothesis and revealed that the main animal source did not statistically significantly affect the levels of minerals and their ratios. However, the analysis of contrasts confirms the differentiation of the content of individual minerals between the groups of foods. For the first time, we proved that pet food with a mineral composition similar to the MIN-RL may be characterized by unfavorable mineral ratios.

Machine learning algorithm as a diagnostic tool for hypoadrenocorticism in dogs

Canine hypoadrenocorticism (CHA) is a life-threatening condition that affects approximately 3 of 1,000 dogs. It has a wide array of clinical signs and is known to mimic other disease processes, including kidney and gastrointestinal diseases, creating a diagnostic challenge. Because CHA can be fatal if not appropriately treated, there is risk to the patient if the condition is not diagnosed. However, the prognosis is excellent with appropriate therapy. A major hurdle to diagnosing CHA is the lack of awareness and low index of suspicion. Once suspected, the application and interpretation of conclusive diagnostic tests is relatively straight forward. In this study, machine learning methods were employed to aid in the diagnosis of CHA using routinely collected screening diagnostics (complete blood count and serum chemistry panel). These data were collected for 908 control dogs (suspected to have CHA, but disease ruled out) and 133 dogs with confirmed CHA. A boosted tree algorithm (AdaBoost) was trained with 80% of the collected data, and 20% was then utilized as test data to assess performance. Algorithm learning was demonstrated as the training set was increased from 0 to 600 dogs. The developed algorithm model has a sensitivity of 96.3% (95% CI, 81.7%-99.8%), specificity of 97.2% (95% CI, 93.7%-98.8%), and an area under the receiver operator characteristic curve of 0.994 (95% CI, 0.984-0.999), and it outperforms other screening methods including logistic regression analysis. An easy-to-use graphical interface allows the practitioner to easily implement this technology to screen for CHA leading to improved outcomes for patients and owners.

Pseudohypoadrenocorticism in a Siberian Husky with Trichuris vulpis Infection

An entire male Siberian Husky presented for diarrhoea, weakness, inappetence, and collapse following a six-day period of illness. On clinical examination the dog displayed vasoconstrictive circulatory shock, dehydration, and melena. Laboratory tests revealed a marked hyponatraemia, hyperkalaemia, and a decreased sodium/potassium ratio of ≤ 12.4. The baseline and poststimulation serum cortisol concentrations were markedly elevated following adrenocorticotropin hormone (ACTH) stimulation test, yielding 712 nmol/L and 706 nmol/L, respectively. The elevated cortisol concentration excluded hypoadrenocorticism. A concurrent Trichuris vulpis (whipworm) infection was also identified. The dog was treated with supportive care including fenbendazole and recovered uneventfully. The final diagnosis was Trichuris vulpis infection with secondary pseudohypoadrenocorticism. This case report further supports a previous observation that the Siberian Husky breed may have an increased sensitivity to infection with Trichuris vulpis and development of pseudohypoadrenocorticism.

Electrolyte Disturbances Are Associated with Non-Survival in Dogs-A Multivariable Analysis

Electrolyte disorders have been individually associated with mortality in small populations of dogs and cats with specific conditions, but the associations and interactions between electrolyte disturbances and outcome have not been evaluated in a large, heterogeneous population. It was hypothesized that abnormalities of sodium, chloride, potassium, and calcium concentrations would be independently and proportionately associated with death from natural causes and with all-cause mortality in dogs. An electronic database containing 33,117 electrolyte profiles was constructed to retrospectively assess the association between disorders of sodium, potassium, corrected chloride, and ionized calcium concentrations with non-survival and with death excluding euthanasia by multivariable modeling. A second database containing 11,249 records was used to validate the models constructed from the first database. All four electrolytes assessed had non-linear U-shaped associations with case fatality rates, wherein concentrations clustered around the reference interval had the lowest case fatality rates, while progressively abnormal concentrations were associated with proportionately increased risk of non-survival (AUROC 0.624) or death (AUROC 0.678). Multivariable modeling suggested that these electrolyte disturbances were associated with non-survival and with death from natural causes independent of each other. This study suggests that measurement of electrolyte concentrations is an important component of the assessment of dogs in emergency rooms or intensive care units. Future studies should focus on confirming these associations in a prospective manner accounting for disease severity.

Factors that affect stabilisation times of canine spontaneous hypoadrenocorticism

The objective of this retrospective study was to examine factors that may have affected the stabilisation times of 50 dogs with spontaneous hypoadrenocorticism that were being treated with fludrocortisone acetate, with particular emphasis on dosing frequency and the concurrent use of prednisolone. Stabilisation was defined as an absence of clinical signs with a sodium:potassium ratio >27:1 and both electrolyte concentrations within a laboratory reference range. It was found that the median time till stabilisation was three months. The frequency of fludrocortisone treatment (once, twice or changed from once to twice a day) had no effect on the stabilisation time. The two groups of dogs that were started and stabilised on once a day or twice a day dosing had a median stabilisation time of two months. However, dogs that failed to stabilise on once a day dosing of fludrocortisone and were then changed onto twice a day dosing then stabilised a median of one month later. Concurrent use of prednisolone resulted in significantly faster stabilisation times. It was concluded that dogs with hypoadrenocorticism should be continued on prednisolone therapy until they are stabilised. If a dog is failing to stabilise on once a day fludrocortisone acetate, a change to twice a day administration could be considered.

Evaluation of the Cortisol-to-ACTH Ratio in Dogs with Hypoadrenocorticism, Dogs with Diseases Mimicking Hypoadrenocorticism and in Healthy Dogs

Background

The adrenocorticotropic hormone (ACTH) stimulation test is the gold standard for diagnosing hypoadrenocorticism (HA) in dogs. However, problems with the availability of synthetic ACTH (tetracosactrin/cosyntropin) and increased costs have prompted the need for alternative methods.

Objectives

To prospectively evaluate the cortisol‐to‐ACTH ratio (CAR) as a screening test for diagnosing canine HA.

Animals

Twenty three dogs with newly diagnosed HA; 79 dogs with diseases mimicking HA; 30 healthy dogs.

Methods

Plasma ACTH and baseline cortisol concentrations were measured before IV administration of 5 μg/kg ACTH in all dogs. CAR was calculated and the diagnostic performance of ACTH, baseline cortisol, CAR and sodium‐to‐potassium ratios (SPRs) was assessed based on receiver operating characteristics (ROC) curves calculating the area under the ROC curve.

Results

The CAR was significantly lower in dogs with HA compared to that in healthy dogs and in those with diseases mimicking HA (P < .0001). There was an overlap between HA dogs and those with HA mimicking diseases, but CAR still was the best parameter for diagnosing HA (ROC AUC 0.998), followed by the ACTH concentration (ROC AUC 0.97), baseline cortisol concentration (ROC AUC 0.96), and SPR (ROC AUC 0.86). With a CAR of >0.01 the diagnostic sensitivity and specificity were 100% and 99%, respectively.

Conclusion and Clinical Importance

Calculation of the CAR is a useful screening test for diagnosing primary HA. As a consequence of the observed overlap between the groups, however, misdiagnosis cannot be completely excluded. Moreover, additional studies are needed to evaluate the diagnostic reliability of CAR in more dogs with secondary HA.

Cirurgia laparoscópica no diagnóstico de gastrite crônica atrófica seguida de tratamento clínico em cadela: relato de caso

Descrevem-se o diagnóstico e o tratamento de um caso de gastrite atrófica crônica, em uma cadela sem raça definida, de dois anos de idade. A paciente apresentava como principal sintomatologia vômito crônico. O hemograma, a urinálise e as avaliações bioquímicas séricas não revelaram alterações significativas. Os exames radiológicos e ultra-sonográficos abdominais também não foram sugestivos de alterações. Realizaram-se inspeção da cavidade peritoneal, gastrotomia, gastroscopia, gastrectomia para biopsia e gastrorrafia intracorpórea videolaparoscópicas. Constatou-se ausência de rugosidades estomacais. Ao exame histológico, observou-se atrofia das células principais e parietais da mucosa gástrica. O quadro clínico permitiu o diagnóstico de gastrite crônica atrófica. O animal foi medicado com terapia imunossupressora e apresentou remissão completa dos sinais clínicos.

Combined hyponatremia and hyperkalemia mimicking acute hypoadrenocorticism in three pregnant dogs

Differential diagnoses for hyponatremia with concurrent hyperkalemia should include hypoadrenocorticism. Renal failure, chylothorax, and gastrointestinal tract disorders may also cause abnormally low serum sodium:potassium ratios. The ACTH stimulation test is the gold standard for diagnosis of hypoadrenocorticism.