Thyroid function tests during nonthyroidal illness syndrome and recovery in acutely ill dogs.

Background: Nonthyroidal illness syndrome (NTIS) can result in thyroid function test alterations that mimic hypothyroidism. The duration of NTIS-induced changes in dogs is not well-described.

Objectives: Document alterations in thyroid function tests during NTIS and recovery, and the time necessary for their resolution.

Influence of medications on thyroid function in dogs: An update.

Erroneous thyroid function test results can occur because of drugs that alter thyroid hormone physiology in one or more aspects, including synthesis, secretion, distribution, and metabolism. Research since publication of the last review in the Journal of Veterinary Internal Medicine (JVIM) 20 years ago has evaluated the effects of amiodarone, zonisamide, inhalant anesthetics, clomipramine, trilostane, and toceranib on thyroid function tests in the dog. In addition, recent work on the effects of glucocorticoids, sulfonamides, phenobarbital, and nonsteroidal anti-inflammatory drugs will be reviewed.

Evaluation of gallbladder motility assessed by ultrasonography in dogs with hyperlipidemia.

Background: The pathogenesis of gallbladder (GB) mucoceles in dogs is unknown. It has been proposed that hyperlipidemia could impair GB motility and contribute to GB mucocele formation.

Hypothesis/objectives: The objective of this study was to compare GB motility in dogs with hyperlipidemia to control dogs using ultrasonography.

Evaluation of hemostasis in hyperthyroid cats.

Background: Hyperthyroid cats might have a predisposition to arterial thrombus formation. The mechanism for thrombogenesis currently is unknown but could be associated with systemic hypercoagulability as seen in hyperthyroid humans.

Objective: Our purpose was to evaluate markers of hemostasis in hyperthyroid cats compared to healthy cats, and in hyperthyroid cats before and after radioactive iodine treatment (RIT).

Bile duct obstruction associated with pancreatitis in 46 dogs.

Background: Pancreatitis is a common cause of extrahepatic bile duct obstruction (EHBDO) in dogs. Information describing the clinical course of dogs with pancreatitis associated bile duct obstruction (PABDO) is limited.

Objectives: To describe the clinical course of PABDO in dogs and determine if presumed markers of disease severity are predictors of survival.

Prevalence of, and factors associated with, positive urine cultures in hyperthyroid cats presenting for radioiodine therapy.

Objectives: Urinary tract infections (UTIs) are reported to be relatively common in hyperthyroid cats, with prevalence rates ranging from 12% to 22%. Factors that are associated with UTIs include age, decreasing body weight and active urine sediments. The purpose of this study was to investigate the prevalence of positive urine cultures (PUCs) in hyperthyroid cats and associated risk factors for PUC.

Platelet function in cats with hyperthyroidism.

Objectives: Cats with hyperthyroidism have been reported to develop thromboembolism, with and without echocardiographic abnormalities consistent with hyperthyroidism. The objective of this study was to compare platelet function in cats with hyperthyroidism with euthyroid age-matched cats. We hypothesized that cats with hyperthyroidism have shortened collagen and adenosine diphosphate (C-ADP) closure times as measured with the platelet function analyzer (PFA-100) in comparison with healthy, age-matched controls.

Levothyroxine supplementation in hypothyroid bitches during pregnancy.

Hypothyroidism is the most common endocrine disease in dogs and has been shown to have a hereditary nature in many breeds. Previous studies have documented decreased fertility in bitches with experimentally-induced hypothyroidism, decreased viability at birth, increased periparturient mortality, and reduced birth weight in pups born to hypothyroid dogs. Hypothyroid women have an increased demand for exogenous thyroxine throughout gestation in order to maintain normal plasma concentrations of thyroid hormones and produce neuropsychologically normal children.

Symmetric dimethylarginine in hyperthyroid cats before and after treatment with radioactive iodine.

Objectives: The purpose of this study was to evaluate symmetric dimethylarginine (SDMA) in hyperthyroid cats before and after treatment with radioactive iodine and to determine how pretreatment SDMA relates to the development of post-treatment azotemia.

Methods: Eighty-four non-azotemic hyperthyroid cats had serum SDMA and creatinine evaluated before and 1, 3 and 6 months after treatment with radioiodine therapy.

Results: Baseline SDMA was increased in 7% (n = 6/84) of cats, whereas SDMA was increased in 19% (n = 15/81), 20% (n = 16/80) and 32% (n = 26/81) at 1 month, 3 months and 6 months after treatment, respectively.

Adrenocortical Challenge Response and Genomic Analyses in Scottish Terriers With Increased Alkaline Phosphate Activity.

Scottish terriers (ST) frequently have increased serum alkaline phosphatase (ALP) of the steroid isoform. Many of these also have high serum concentrations of adrenal sex steroids. The study's objective was to determine the cause of increased sex steroids in ST with increased ALP.

Investigation of a novel variable dosing protocol for radioiodine treatment of feline hyperthyroidism.

Background: Radioiodine is the treatment of choice for hyperthyroidism in cats. The ideal method of dose determination of radioiodine remains controversial.

Objective: To compare a method of radioiodine dose determination that utilized thyroid scintigraphy with a standard fixed dose for treatment of hyperthyroidism.

Thyrotoxicosis induced by excessive 3,5,3'-triiodothyronine in a dog.

CASE DESCRIPTION A 7-year-old castrated male Havanese was evaluated at a veterinary teaching hospital because of a 12-week history of hyperactivity, aggression, and progressive weight loss despite a healthy appetite. CLINICAL FINDINGS Tachycardia was the only remarkable finding during physical examination. Serum 3,5,3'-triiodothyronine (T3) and free T3 concentrations were markedly increased, and thyroxine (T4), free T4, and thyroid-stimulating hormone concentrations were at or decreased from the respective reference ranges.

EVALUATION OF THYROID TO BACKGROUND RATIOS AND COMPARISON OF VARIOUS SCINTIGRAPHIC MEASUREMENTS AND THEIR CORRELATION TO SERUM T4 IN HYPERTHYROID CATS.

Thyroid-to-salivary ratio and percent dose uptake are the most widely recognized scintigraphic measurements. Recently, the thyroid-to-background ratio has been proposed as an alternate method. However, this method has not been validated.

Blastomycosis in a postpartum dog.

Transplacental infection with Blastomyces dermatitidis is rare in humans and unknown in the dog. A Doberman pinscher bitch was diagnosed with blastomycosis 25 days after whelping. Clinical signs were noted after whelping and were progressive.

The effect of experimentally induced hypothyroidism on the isoflurane minimum alveolar concentration in dogs.

Objective: To determine the effect of experimentally induced hypothyroidism on isoflurane (ISO) minimum alveolar concentration (MAC) in dogs.

Study Design: Prospective experimental study.

Animals: Eighteen adult female mongrel dogs, age 2-4 years and weighing 8.

Cardiovascular effects of thyroid disease.

Thyroid hormones have many effects on cardiovascular function, and deficiency or excess of thyroid hormones can result in cardiac dysfunction. Abnormalities of the cardiovascular system are often identified during examination of hyperthyroid and hypothyroid patients. This article addresses the effects of thyroid hormones on the cardiovascular system and the clinical relevance of the cardiovascular response to thyroid dysfunction.

Mixed infection caused by Lecythophora canina sp. nov. and Plectosphaerella cucumerina in a German shepherd dog.

We describe an opportunistic, disseminated infection in a German shepherd dog associated with two fungal organisms not previously reported to cause disease. Lecythophora canina, a new species here described, was isolated from an osteolytic bone lesion. A fine needle aspirate of the lesion demonstrated septate hyphae.

Effects of oral prednisone administration with or without ultralow-dose acetylsalicylic acid on coagulation parameters in healthy dogs.

Objective: To determine the effects of oral prednisone administration with or without ultralow-dose acetylsalicylic acid on coagulation parameters in healthy dogs and to assess intraindividual variation in thromboelastography results.

Animals: 14 healthy research dogs and 10 healthy client-owned dogs.

Procedures: In a randomized controlled trial, research dogs underwent thromboelastography twice (3 days apart), and intraindividual variation in test results was calculated.

Effect of hypothyroidism on insulin sensitivity and glucose tolerance in dogs.

Objective: To determine the effects of hypothyroidism on insulin sensitivity, glucose tolerance, and concentrations of hormones counter-regulatory to insulin in dogs.

Animals: 8 anestrous mixed-breed bitches with experimentally induced hypothyroidism and 8 euthyroid control dogs.

Procedures: The insulin-modified frequently sampled IV glucose tolerance test and minimal model analysis were used to determine basal plasma insulin and glucose concentrations, acute insulin response to glucose, insulin sensitivity, glucose effectiveness, and disposition index.

Efficacy of iopanoic acid for treatment of spontaneous hyperthyroidism in cats.

Iopanoic acid is an iodine containing oral cholecystographic agent that has been used to treat hyperthyroidism in humans and has recently been evaluated in an experimental model of feline hyperthyroidism. The aim of this study was to evaluate the efficacy of iopanoic acid in cats with spontaneous hyperthyroidism. Eleven cats were included in the study.

Blood-brain-barrier disruption in chronic canine hypothyroidism.

Background: Central nervous system (CNS) manifestations of hypothyroidism have been associated with cerebrovascular complications. Reports of cerebrospinal fluid (CSF) abnormalities are rare in hypothyroid dogs.

Objective: The aim of this study was to determine if chronic hypothyroidism causes blood-brain-barrier (BBB) abnormalities that are detectable using indirect CSF biomarkers.

Hyperphosphatasemia and concurrent adrenal gland dysfunction in apparently healthy Scottish Terriers.

Objective: To determine causes of hyperphosphatasemia (high serum alkaline phosphatase [ALP] activity) in apparently healthy Scottish Terriers.

Design: Prospective case-controlled study.

Animals: 34 apparently healthy adult Scottish Terriers (17 with and 17 without hyperphosphatasemia).

Longitudinal study of the effects of chronic hypothyroidism on skeletal muscle in dogs.

Objective: To study the effects of experimentally induced hypothyroidism on skeletal muscle and characterize any observed myopathic abnormalities in dogs.

Animals: 9 female, adult mixed-breed dogs; 6 with hypothyroidism induced with irradiation with 131 iodine and 3 untreated control dogs.

Procedures: Clinical examinations were performed monthly.

Effects and safety of iopanoic acid in cats administered levothyroxine.

The purpose of this study was to evaluate the safety and effect of iopanoic acid in 13 cats with hyperthyroidism induced by daily subcutaneous administration of 25microg/kg levothyroxine for a period of 42 days. On day 28 of levothyroxine administration, cats were randomly allocated to receive treatment twice daily with a placebo (control group; n=4), 50mg iopanoic acid (low dose group; n=5), or 100mg iopanoic acid (high dose group; n=4) for 14 days. Compared to the control group, T(3) concentrations were significantly decreased in both the low dose and high dose groups on days 35 and 42.

Hypothyroid-associated central vestibular disease in 10 dogs: 1999-2005.

Background: With the exception of myxedema coma, central nervous system signs are rare in hypothyroid dogs.

Hypothesis: Central vestibular dysfunction is a possible and reversible manifestation of hypothyroidism.

Animals: Medical records of dogs with vestibular dysfunction and hypothyroidism were reviewed.