Serum thyrotropin, thyroxine and free thyroxine concentrations as predictors of mortality in critically ill puppies with parvovirus infection: a model for human paediatric critical illness?

Total thyroxine, triiodothyronine, and thyrotropin concentrations during acute nonthyroidal illness and recovery in dogs

BACKGROUND

Acute illness can result in changes in serum total thyroxine (tT4), total triiodothyronine (tT3), and thyrotropin (TSH) concentrations in euthyroid dogs defined as nonthyroidal illness syndrome, but longitudinal evaluation of these hormones during the recovery phase is lacking.

OBJECTIVES

To longitudinally evaluate serum tT4, tT3, and TSH concentrations during the acute phase and recovery from acute illness in dogs.

ANIMALS

Nineteen euthyroid client-owned dogs hospitalized for acute illness at a veterinary teaching hospital.

METHODS

Prospective longitudinal study. Serum tT4, tT3, and TSH concentrations were measured at the admission (T0), at last day of hospitalization (T1), and during the recovery phase at 3, 7, 14, and 21 days after the discharge (T2, T3, T4, and T5), respectively.

RESULTS

tT4 and tT3 were below the reference interval (RI) at T0 in 3 (16%) and 18 (95%) dogs, respectively; tT4 normalized in all dogs early in the recovery phase, while low tT3 persisted at the end of the study in 16 (83%) dogs. Median TSH concentrations were increased at T5 compared with T1 (0.19 ng/mL [range 0.03-0.65] vs 0.11 ng/mL [range (0.05-0.26)], mean difference = 0.09 ng/mL; P = .03). Five (26%) dogs had TSH above the RI at least at 1 time point during the recovery phase. None of the dogs had concurrent low tT4 and high TSH during the study.

CONCLUSIONS AND CLINICAL RELEVANCE

In euthyroid dogs acute illness can interfere with evaluation of thyroid function up to 21 days during the recovery phase. Thyroid testing should be avoided or postponed in these dogs.

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.

ANIMALS

From 103 dogs sampled, 25 euthyroid dogs with acute, resolvable illness having a low serum total thyroxine (TT4) concentration on admission were analyzed.

METHODS

Prospective observational study. Serum TT4 concentration was measured in 103 dogs within 4 hours of admission. If below the reference interval (RI), subsequent serum samples were obtained every 24 hours from admission until discharge (acute phase) and at 2 weeks and 4 weeks after discharge (recovery phase). Serum samples were submitted for batch measurement of serum TT4, free thyroxine (fT4), total 3,5,3'-triiodothyronine (TT3), and thyroid-stimulating hormone (TSH) concentrations.

RESULTS

In the cohort of dogs analyzed, serum TT4, TT3, and fT4 concentrations were below the RI in 100%, 80%, and 16% at admission; 20%, 80%, and 0% at discharge; 4%, 8%, and 0% at 2 weeks; and 0%, 0%, and 0% at 4 weeks, respectively. Serum TSH concentration was within the RI in 100% at admission and discharge, and above the RI in 4% and 12% at 2 weeks and 4 weeks, respectively.

CONCLUSIONS AND CLINICAL IMPORTANCE

Naturally occurring NTIS in dogs induces alterations in thyroid function tests during acute illness and recovery. Measurement of serum TT4 concentration 2 to 4 weeks after discharge or serum fT4 concentration by ED during illness is recommended for accurate assessment of thyroid function in acutely ill dogs.

The Diverse Pathogenicity of Various Babesia Parasite Species That Infect Dogs

Babesia species infect a very wide range of mammal hosts across the globe, and zoonotic infections are of growing concern. Several species of the Babesia genus infect dogs, and some of these cause significant morbidity and mortality. The Apicomplexan parasite resides within the red cell and infections result in direct damage to the host through intra- and extravascular hemolysis. An exuberant inflammatory response by the host to some species of Babesia parasites also results in significant collateral damage to the host. Canine infections have been the subject of many studies as the well-being of these companion animals is increasingly threatened by the spread of tick vectors and an increasingly mobile dog population. There are currently no widely available and effective vaccines, and effective treatment can be challenging. Understanding disease pathogenesis underlies the development of new treatments. The varying pathogenicity of the various Babesia parasite species that infect dogs offers an opportunity to explore the molecular basis for the wide range of diseases caused by infection with this parasite genus. In this review, we focus on what has been reported about the clinical presentation of Babesia-infected dogs in an attempt to compare the severity of disease caused by different Babesia species.

Serial changes in the concentrations of cortisol and thyroid hormones in Beagle dogs infected with Babesia rossi

An experimental infection using Babesia (B.) rossi was performed in healthy male Beagle dogs to assess the changes in endocrine variables during disease. Two dogs were infected with a low dose (LD) of parasite inoculum (10⁴ parasites) and three dogs were infected with a high dose (HD) (10⁸ parasites). Basal serum cortisol, thyroxine (T4), and thyrotropin (TSH) concentrations were measured every second day. Samples were analyzed using a solid- phase, competitive chemiluminescent enzyme immunoassay (Immulyte® 2000, Siemens). Variables were compared between groups and timepoints using linear mixed models. In both groups, the median cortisol concentration increased, whilst the median T4 concentration decreased after infection, with a return towards baseline concentration post treatment. The highest cortisol and the lowest T4 concentrations were reached at 96 h and 108 h post infection, respectively, in the HD group and slightly later at 108 and 144 h post-infection, respectively, in the LD group. A higher cortisol concentration with a more rapid increase, and a lower T4 concentration with a more rapid decline, were associated with disease severity and a higher dose of parasite inoculum. The TSH concentration remained within the reference interval throughout the study period. This study illustrated the temporal changes in endocrine parameters during experimental B. rossi infection and demonstrated that cortisol and T4 tracked the severity of disease, albeit in opposite directions.

Serial measurement of thyroid hormones in hospitalised dogs with canine parvoviral enteritis: Incidence of non-thyroidal illness syndrome and its association with outcome and systemic inflammatory response syndrome

The aim of this study was to serially evaluate the serum concentrations of total thyroxine (tT4), free thyroxine (fT4) and thyroid-stimulating hormone (TSH) in dogs with canine parvoviral enteritis (CPVE) during a 5-day hospitalisation period and assess the association of these hormone concentrations with the outcome and the development of systemic inflammatory response syndrome (SIRS). Dogs with confirmed CPVE that were hospitalised for at least 5 days were included. The thyroid hormones concentrations were measured on days 1, 3 and 5 of hospitalisation. Twenty-eight dogs were included. All (28/28, 100%), 19/28 (69.7%) and 23/28 (82.1%) dogs had a low serum tT4, fT4 and TSH concentration, respectively, on at least 1 day during the hospitalisation period. Overall, 11/28 (39.3%) dogs were diagnosed with SIRS on at least 1 day. In survivors, serum tT4 concentration was significantly higher on day 5 (median, range: 11.8 nmol/L, <6.4-32.2 nmol/L) compared to those on days 1 (<6.4 nmol/L, <6.4-20.1 nmol/L; P = 0.010) or 3 (7.6 nmol/L, <6.4-25.2 nmol/L; P = 0.019). Survivors had a significantly higher tT4 concentration (median, range: 11.8 nmol/L, <6.4-32.2 nmol/L) on day 5 compared to non-survivors (<6.4 nmol/L, <6.4-7.2 nmol/L; P = 0.002). Regardless of the day of hospitalisation, dogs with SIRS had significantly lower tT4 (<6.4 nmol/L, <6.4-16.3 nmol/L) compared to dogs without SIRS (8.6 nmol/L, <6.4-32.2 nmol/L; P = 0.006). A significant difference was also found in fT4 between dogs with SIRS (<3.9 pmol/L, <3.9-16.2 pmol/L) and dogs without SIRS (15.1 pmol/L, <3.9-59.2; pmol/L; P < 0.001). Non-thyroidal illness syndrome was frequently observed in dogs with CPVE, and a negative association between tT4 and fT4 concentrations and SIRS was noted. Serial measurements of tT4 concentrations appeared to have prognostic value.

Prognostic indicators at presentation for canine parvoviral enteritis: 322 cases (2001-2018)

OBJECTIVE

To evaluate clinicopathological prognostic indicators associated with survival based on hematology and serum biochemistry profile findings at presentation of dogs with canine parvoviral enteritis (CPE). Secondary objectives were to describe the signalment, history, physical examination findings, and progression of disease while in hospital and correlate them to survival.

DESIGN

Retrospective study from medical records of dogs diagnosed with CPE between 2001 and 2018.

SETTING

University teaching hospital.

ANIMALS

Three hundred twenty-two dogs diagnosed with CPE that received in-hospital treatment.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 322 hospitalized dogs, 294 dogs (91%) survived infection with a median hospitalization time of 79 hours. Multivariable analysis showed that glucose (P = 0.04), total magnesium (P = 0.011), and the dichotomized variable of a low HCT (P = 0.033) on presentation were significantly associated with survival. For every 1 mmol/L (18 mg/dL) decrease in glucose concentration, cases had 1.85 lower odds of survival. For every 0.1 mmol/L (0.2 mEq/L) increase in total magnesium concentration, cases had 2.50 lower odds of survival. Cases with a low HCT had 10.69 lower odds of survival. On univariable analyses, non-survivors had a lower median body weight (P = 0.006) and presented more commonly for diarrhea (P = 0.015). At least 1 episode of diarrhea (P = 0.003) and hematochezia or melena (P < 0.001) in hospital were negatively associated with outcome, in addition to the persistence of diarrhea (P = 0.026) and hyporexia (P = 0.018) in hospital for 5 to 6 days.

CONCLUSIONS

Survival rates of 91% were achieved with in-hospital treatment in this cohort of dogs. Negative biochemical prognostic indicators affecting survival include a low HCT, decreased blood glucose concentrations, and increased total serum magnesium concentrations at presentation.

Serum thyroxine and thyrotropin concentrations decrease with severity of nonthyroidal illness in cats and predict 30-day survival outcome

Background

In cats, nonthyroidal illness affects serum thyroid hormone concentrations. Serum thyroxine (T₄) and triiodothyronine (T₃) concentrations commonly decrease, whereas free T₄ (fT₄) concentrations vary unpredictably. Limited information exists regarding effects on serum thyrotropin (thyroid‐stimulating hormone [TSH]) concentrations in cats with nonthyroidal illness syndrome (NTIS).

Objectives

To characterize alterations in thyroid function that develop in cats with NTIS and to correlate these alterations with severity and outcome of the nonthyroidal illness.

Animals

Two hundred and twenty‐two cats with NTIS and 380 clinically normal cats of similar age and sex.

Methods

Prospective, cross‐sectional study. All cats had serum T₄, T₃, free T₄, and TSH concentrations measured. Cats were grouped based on illness severity and 30‐day survival.

Results

Cats with NTIS had lower serum T₄ and T₃ concentrations than did normal cats (P < .001). Serum fT₄ and TSH concentrations did not differ between groups. Serum T₄, T₃, and fT₄ concentrations progressively decreased with increasing disease severity (P < .001). The 56 cats that died had lower T₄, T₃, and TSH concentrations than did the 166 survivors, with no difference in fT₄ concentration. Multivariable logistic regression modeling indicated that serum T₄ and TSH concentrations both predicted survival (P < .02).

Conclusions and Clinical Importance

Cats with NTIS commonly develop low serum T₄, T₃, and TSH concentrations, the prevalence and extent of which increases with disease severity. Clinicians should consider evaluating thyroid function in cats with severe NTIS, because doing so could help determine probability of successful treatment responses before investing considerable time, effort, and finances in addressing the underlying disease.

Assessment of certain biomarkers for predicting survival in response to treatment in dogs naturally infected with canine parvovirus

Canine parvovirus (CPV) enteritis is an important cause of morbidity and mortality in puppies despite aggressive treatment. Identification of reliable biomarkers for CPV enteritis is essential to determine the severity, duration of hospitalization, and predict the clinical outcome. Meanwhile, the biomarkers will assist in decision-making with clients about the further course of treatment or euthanasia. The present study was conducted to evaluate the changes of total leukocyte count (TLC), neutrophil count, and serum concentrations of creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), intestinal fatty acid binding protein-2 (IFABP-2), albumin, ceruloplasmin (Cp), cortisol, free triiodothyronine (FT₃) and free thyroxine (FT₄) in survivors and non-survivors as a predictor of the clinical outcome. Marked leukopenia, neutropenia, hypoalbuminemia, elevated levels of CK-MB, IFABP-2, Cp, and cortisol were noticed in CPV-infected dogs than healthy dogs but, LDH, FT₃ and FT₄ concentrations did not differ significantly. The CPV-infected non-survivors had persistent leukopenia, neutropenia and elevated CK-MB, IFABP-2, Cp and cortisol concentrations at 72 h of commencement of treatment. In CPV-infected survivors, TLC and neutrophil count were significantly increased, and CK-MB, IFABP-2, Cp and cortisol concentrations were significantly decreased at 72 h of commencement of treatment. The positive predictive values (PPVs) for survival using cut-off value of TLC (>3.2 × 10³/μL), neutrophil count (>1.65 × 10³/μL), CK-MB (≤234.50 U/L), IFABP-2 (≤7.61 ng/mL), Cp (≤0.605 g/L) and cortisol (≤16.90 ng/mL) were determined as 89.47%, 88.88%, 94.73%, 93.33%, 94.44% and 89.47%, respectively with better area under receiver operating characteristic (ROC) curve as well as sensitivity. The magnitude of decrease in TLC, neutrophil count, and increase in CK-MB, IFABP-2, Cp and cortisol concentrations at 72 h of initiation of treatment in dogs with parvoviral enteritis could be useful indicators for the prognosis of the disease. Based on sensitivity (%) and specificity (%) from ROC curve analysis and PPV (%), it is concluded that serum CK-MB concentration will serve as the most useful biomarker followed by Cp and absolute neutrophil count.

Update on Canine Parvoviral Enteritis

Canine parvoviral enteritis is one of the most common causes of morbidity and mortality in dogs worldwide. Tests can detect viral antigen in feces, and characteristic decreases in total leukocyte, neutrophil, and lymphocyte counts can increase the index of suspicion in affected cases and can be used to prognosticate morbidity and mortality. The standard of care for infected animals includes IV crystalloid and sometimes colloid fluids, antiemetics, broad-spectrum antibiotics, and early enteral nutrition. Vaccination induces protective immunity in most dogs. Vaccination, along with limiting exposure in young puppies, is the most effective means of preventing parvoviral enteritis in dogs.

Thyroid axis and adrenal activity in 28 day survivor and nonsurvivor dogs involved in recent road traffic accidents: A cohort study of 420 dogs

The objective of this retrospective cohort study was to determine the impact of a recent trauma on thyroid axis and adrenal activity in dogs and to assess the usefulness of urinary cortisol-to-creatinine ratio (UCCR), basal serum thyroid-stimulating hormone (TSH), total thyroxine (tT4), and free thyroxine (fT4) concentrations in predicting outcome in dogs traumatized by a road traffic accident (RTA). An RTA exposed group of 210 dogs was evaluated within 24  hours of the trauma. Their data were compared with data from a matched group of dogs with other diagnoses. UCCR was positively correlated with the trauma severity and was higher in the exposed group than in the nonexposed group (median 101.500 vs. 21.02; p < 0.0001). tT4 values were statistically similar between the two groups, but were correlated with a trauma score, while TSH (median = 0.050 vs. 0.080 ng/mL; p < 0.0001) and fT4 (median = 15.850 vs. 17.950 pmol/L; p = 0.0037) were significantly lower for the exposed group. Nonsurvivors in comparison to survivors presented and higher median UCCR (181.800 vs. 93.850 respectively; p = 0.020), and a lower serum fT4 (12.700 vs. 16.500 pmol/L, respectively; p = 0.0046). A similar pattern had been observed for tT4. TSH levels were not predictive of survival. This study provides insights into the endocrine characteristics of dogs suffering from acute trauma. UCCR was higher while fT4 and TSH were both lower in RTA-injured dogs than in dogs affected by other conditions. Furthermore low fT4 and tT4, and a high UCCR could be useful prognostic factors in dogs affected by RTA trauma.

Retrospective evaluation of outpatient canine parvovirus treatment in a shelter-based low-cost urban clinic

OBJECTIVE

To evaluate survival and associated risk factors when utilizing an outpatient treatment protocol for treatment of canine parvovirus (CPV) performed in a shelter-based low-cost urban clinic.

DESIGN

Retrospective study.

SETTING

Pennsylvania Society for the Prevention of Cruelty to Animals.

ANIMALS

Ninety-five CPV positive dogs presented between June 1 and July 31, 2016. Owners elected for outpatient care when inpatient care was not financially feasible and the dog was considered medically stable for outpatient care.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 95 CPV positive dogs, 79 (83%) survived treatment. Logistic regression indicated that an increasing number of days with clinical signs prior to treatment and an increase in percent body weight during treatment were significantly associated with survival (odds ratio [OR], 3.15, P = 0.020; and OR, 1.29, P = 0.027, respectively). Hypothermia upon presentation (T < 37℃) was negatively associated with survival (OR, 0.002; P = 0.002).

CONCLUSIONS AND CLINICAL RELEVANCE

The survival rate of this clinic suggests that an outpatient program may be a potential alternative treatment to inpatient care. Longer duration of clinical signs prior to treatment and an increase in percent body weight during treatment appear to be associated with increased survival outcomes, while hypothermia on presentation appears to be associated with decreased survival outcomes.

Prognostic value of systemic inflammatory response syndrome and serum concentrations of acute phase proteins, cholesterol, and total thyroxine in cats with panleukopenia

Background

Feline parvovirus (FPV) is a common and potentially lethal infectious agent in cats.

Objective

To assess the prognostic value of age, neuter status, serum concentrations of serum amyloid A (SAA), haptoglobin, cholesterol and total thyroxine (tT4), and the presence of systemic inflammatory response syndrome (SIRS) in cats with panleukopenia.

Animals

Client‐owned cats with FPV infection diagnosed by a positive fecal ELISA test, positive PCR on feces or blood or both.

Methods

Retrospective cohort study. The electronic medical database was searched for cats with FPV infection presented between January 2010 and January 2018. Cats were divided into survivors and nonsurvivors according to their survival status 28 days after hospital admission. The prognostic importance of each variable was investigated univariately and by multivariable Cox's proportional‐hazards regression. Finally, receiver operator characteristic (ROC) curve analysis was used to identify the best cutoff value for discriminating survivors from nonsurvivors for the statistically significant prognostic predictors identified by multivariable analysis.

Results

Seventy cats were enrolled in the study. Multivariable analysis determined that only serum tT4 concentration at hospital admission was significantly (P = .01) associated with survival. A cutoff value of 0.82 μg/dL was identified by ROC curve analysis for serum tT4 concentration in discriminating survivors from nonsurvivors. Sensitivity at this cutoff was 73.9% and specificity was 82.9% (area under the curve, 0.783; 95% confidence interval, 0.668‐0.873; P < .0001).

Conclusion and Clinical Relevance

Serum tT4 concentration at hospital admission has prognostic value in cats with FPV infection.

Serum D-lactate concentrations in dogs with parvoviral enteritis

BACKGROUND

Dogs infected with canine parvovirus (CPV) have compromised intestinal epithelial barrier integrity. Production of D-lactate by enteric bacteria may directly reflect disease severity or contribute to metabolic acid-base status in these dogs.

HYPOTHESIS

Serum D-lactate concentration will be increased in CPV dogs compared to healthy controls and correlate with markers of disease severity and acid-base status.

ANIMALS

Dogs with CPV undergoing treatment (n = 40) and healthy control dogs (n = 9).

METHODS

Prospective observational study. Dogs with CPV had a baseline and daily CBC, venous blood gas with serum electrolyte concentrations, composite clinical severity score, and serum D-lactate concentration performed. A single serum D-lactate measurement was obtained from healthy control dogs.

RESULTS

The CPV dogs had a higher D-lactate concentration (mean ± SD) of 469 ± 173 μM compared to controls, 306 ± 45 μM (P < .001). There was no difference in baseline D-lactate concentrations for CPV survivors (474 ± 28 μM), versus nonsurvivors (424 ± 116 μM; P = .70). D-lactate concentration decreased over the first 4 days of treatment (-9.6 μM/d; P = .46). Dogs hospitalized for <4 days had lower baseline D-lactate concentrations compared to those hospitalized ≥4 days (400 ± 178 μM versus 520 ± 152 μM; P = .03). No sustained correlation over time between serum D-lactate concentration and clinical severity score or recorded acid-base results.

CONCLUSIONS AND CLINICAL IMPORTANCE

Serum D-lactate concentrations are higher in dogs with CPV compared to healthy controls but do not appear to be clinically relevant. No relationship identified between serum D-lactate concentrations and markers of CPV disease severity, acid-base status, or outcome.

A clinical and pathological description of 320 cases of naturally acquired Babesia rossi infection in dogs

Babesia rossi causes the most severe clinical disease in dogs of all the babesia parasites. We included 320 naturally-infected dogs that presented for care at the Onderstepoort Veterinary Academic Hospital between 2006 and 2016. All dogs had mono-infections confirmed by multiplex PCR. The data allowed more accurate clinical classification of the disease and identified parameters that were associated with disease severity and death. Odds ratios for dying were significant (P < 0.05) for increased band neutrophil count, collapse at presentation; presence of cerebral signs; hypoglycaemia; hyperlactatemia; high urea, high creatinine; hyperbilirubinaemia; hypercortisolaemia; and hypothyroxinaemia. Joint component analysis confirmed that the variables with significant odds ratios grouped together with death. Yet, multivariate logistic regression was unable to identify a group of significant independent predictors of death. Receiver Operator Characteristic curves indicated that low total thyroid hormone, high bilirubin, high serum urea and high cortisol concentrations were the variables with the highest sensitivity and specificity for death. These data provide both the clinician and researcher with a set of easily-measured laboratory and clinical assessments to classify cases into those that are uncomplicated and those that are complicated. The disease is complex and multisystemic and probably involves mechanisms more proximal in the pathogenesis than those that have been evaluated.

Survival estimates and outcome predictors for shelter cats with feline panleukopenia virus infection

OBJECTIVE To determine survival estimates and outcome predictors for shelter cats with feline panleukopenia virus (FPV) infection. DESIGN Retrospective cohort study. ANIMALS 177 shelter cats with FPV infection. PROCEDURES Medical records of cats treated for FPV infection from 2011 through 2013 were reviewed to collect information pertaining to signalment; history; results of physical examination, CBC, serum biochemical analysis, and blood gas analysis; and treatments (antimicrobials, antiparasitics, antivirals, antiemetics, analgesics, crystalloid or colloid solutions, and blood products). Survival time and outcome predictors were determined by means of Kaplan-Meier estimation, logistic regression, and mixed-model ANOVA. RESULTS Median survival time after hospital admission was 3 days; 20.3% (36/177) of cats survived to discharge from the hospital. Risk of nonsurvival was greater in cats with (vs without) signs of lethargy, rectal temperature < 37.9°C (I00.2°F), or low body weight at hospital admission. Lower (vs higher) leukocyte count on days 3,4, and 7 of hospitalization, but not at admission, was associated with nonsurvival. Amoxicillin-clavulanic acid, antiparasitics, and maropitant but not interferon-ω were associated with survival, whereas glucose infusion was associated with nonsurvival. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that FPV infection carried a poor prognosis for shelter cats. Several variables measured at admission or during hospitalization were associated with outcome. Remarkably and contrary to the existing literature, leukopenia at admission had no association with outcome, possibly owing to early prevention of complications.

Prevalence of Salmonella in juvenile dogs affected with parvoviral enteritis

Salmonellosis is a disease of major zoonotic importance and canine parvovirus is a potentially fatal cause of canine enteritis with a world-wide distribution. Persistent isolation of Salmonella during routine environmental sampling surveys of a hospital ward, reserved for the treatment of dogs with canine parvovirus infection, prompted investigation into a possible source. We hypothesised that dogs affected by canine parvovirus would have a higher prevalence of faecal salmonellae compared to an apparently healthy cohort. Seventy-four client-owned dogs naturally infected with canine parvovirus and 42 apparently healthy client-owned dogs were included in the study. This prospective, longitudinal, observational study was conducted over an 18-month period. Fresh faecal samples were collected from dogs aged 6 weeks to 9 months diagnosed with canine parvovirus infection and admitted for treatment, and from apparently healthy dogs presented for vaccination or routine hospital procedures. Faeces were submitted for the isolation, antimicrobial susceptibility testing and serotyping of salmonellae. The prevalence of faecal Salmonella shedding was 22% and 31% for the affected and apparently healthy dogs, respectively, which was not statistically different. No significant associations between Salmonella status and possible risk factors or continuous variables such as age, body weight and duration of hospitalisation were identified. All the Salmonella isolates (n = 32) were resistant to penicillin G, lincomycin and tylosin. Salmonellae from nine different serotypes were identified. The prevalence of Salmonella shedding in both groups was higher than that commonly reported, yet similar to those in previous reports on young dogs, shelter dogs or dogs fed a raw meat diet.

Retrospective evaluation of circulating thyroid hormones in critically ill dogs with systemic inflammatory response syndrome

Critical illness can be associated with transient alterations in circulating thyroid hormone concentrations, indicating the presence of non-thyroidal illness (NTI). NTI is well described in humans, but there are few reports on its occurrence and prognostic significance in dogs. This retrospective study assessed the occurrence of NTI in a population of dogs with systemic inflammatory response syndrome (SIRS) and investigated its association with disease severity (APPLE_fast scores). A total of 41 SIRS dogs were included and were divided by SIRS origin (non-septic SIRS, n = 10; septic SIRS, n = 41) and final outcome (survivors, n = 37; non-survivors, n = 4). Healthy, age-matched dogs (n = 15) were included as controls. Serum thyroid hormone levels including total T3, free T3, total T4, and reverse T3 were measured upon admission. Compared to controls, there were significant changes in serum thyroid hormone concentrations in SIRS dogs, suggesting the presence of NTI. Septic SIRS dogs had higher APPLE_fast scores and lower serum thyroid hormones concentrations than those in non-septic SIRS and control dogs. In conclusion, NTI was frequent in dogs with SIRS and may be associated with the presence of sepsis or high illness severity.

Low T3 syndrome in canine babesiosis associated with increased serum IL-6 concentration and azotaemia

Low triiodothyronine (T3) syndrome, also named euthyroid sick syndrome or non-thyroidal illness syndrome, has been recognized in canine babesiosis caused by Babesia rossi, where it manifested by lowering of the serum thyrotropin (TSH), total thyroxin (TT4) and free thyroxin (FT4) concentrations. This syndrome has also been observed in critical diseases in humans and animals, and the severity of the disease is considered an important factor in lowering of thyroid hormone concentrations. Interleukin-6 (IL-6) plays a role in the development of low T3 syndrome by causing a decrease in deiodinases 1 and 2 activity and increased activity of deiodinase 3, enzymes involved in the conversion of thyroxin (T4) to T3. The purpose of this study was to compare the concentrations of serum thyroid hormones and TSH between healthy dogs and dogs with babesiosis, and to determine correlations between serum IL-6 concentration and serum total T3 (TT3), TT4, FT4, and TSH concentrations, and the level of azotaemia in dogs with babesiosis. The concentrations of IL-6, TT3, TT4, FT4, TSH, urea and creatinine were determined in 13 dogs with canine babesiosis caused by Babesia canis and in 10 healthy dogs. The results of this study showed decreases in TT3, TT4, FT4, and TSH and increases in IL-6, urea and creatinine concentrations in affected dogs in comparison to healthy dogs. The concentration of IL-6 was negatively correlated with TT3 and TSH concentrations and the TT3 concentration was negatively correlated with serum urea and creatinine concentrations. This study showed low T3 syndrome in canine babesiosis, which was confirmed by the determination of the T3 concentration, and demonstrates that in canine babesiosis the T3 concentration is associated with IL-6 concentration.

Evaluation of serum thyroid hormones in dogs with systemic inflammatory response syndrome or sepsis

OBJECTIVE

To determine whether dogs with systemic inflammatory response syndrome (SIRS) or sepsis have derangements in serum thyroid hormone concentrations and to evaluate whether such derangements relate to illness severity or outcome.

DESIGN

Prospective observational study. Dogs hospitalized with SIRS or sepsis between May and December 2010 were included. Serum thyroid hormone concentrations were measured in all dogs. Data obtained on admission were used to calculate the Acute Patient Physiologic and Laboratory Evaluation (APPLE) scores.

SETTING

University teaching hospital.

ANIMALS

Twenty-two consecutive client-owned dogs hospitalized with SIRS or sepsis were enrolled; 18 dogs completed the study and 4 dogs were excluded for incomplete data. Forty-nine healthy dogs owned by volunteers were used as controls.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Decreased total thyroxine (TT4) concentrations were documented in all septic and 7/9 dogs with SIRS. Free T4 concentrations were decreased, but were within the reference interval in 12/18 dogs with SIRS or sepsis compared to control dogs (P < 0.001). Dogs with increased APPLE(fast) scores were less likely to survive (P = 0.017).

CONCLUSIONS

Dogs with SIRS or sepsis have derangements in measured serum thyroid hormones. No relationships were identified between thyroid hormone concentrations and survival. The APPLE(fast) score was the only variable predictive of poor outcome.

The central role of chloride in the metabolic acid-base changes in canine parvoviral enteritis

The acid–base disturbances in canine parvoviral (CPV) enteritis are not well described. In addition, the mechanisms causing these perturbations have not been fully elucidated. The purpose of the present study was to assess acid–base changes in puppies suffering from CPV enteritis, using a modified strong ion model (SIM). The hypothesis of the study was that severe acid–base disturbances would be present and that the SIM would provide insights into pathological mechanisms, which have not been fully appreciated by the Henderson–Hasselbalch model.

The study analysed retrospective data, obtained from 42 puppies with confirmed CPV enteritis and 10 healthy control dogs. The CPV-enteritis group had been allocated a clinical score, to allow classification of the data according to clinical severity. The effects of changes in free water, chloride, l-lactate, albumin and phosphate were calculated, using a modification of the base excess algorithm. When the data were summated for each patient, and correlated to each individual component, the most important contributor to the metabolic acid–base changes, according to the SIM, was chloride (P < 0.001). Severely-affected animals tended to demonstrate hypochloraemic alkalosis, whereas mildly-affected puppies had a hyperchloraemic acidosis (P = 0.007). In conclusion, the acid–base disturbances in CPV enteritis are multifactorial and complex, with the SIM providing information in terms of the origin of these changes.

Canine parvovirus

Since its emergence in 1978, canine parvoviral enteritis has remained a common and important cause of morbidity and mortality in young dogs. The continued incidence of parvoviral enteritis is partly due to the virus's capability to "reinvent" itself and evolve into new, more virulent and resistant subspecies. This article reviews current knowledge about the virus, its epidemiology, clinical manifestation, diagnosis, management, and prevention.

Interactions between thyroid and kidney function in pathological conditions of these organ systems: a review

Thyroidal status affects kidney function already in the embryonic stage. Thyroid hormones influence general tissue growth as well as tubular functions, electrolyte handling and neural input. Hyper- and hypo-functioning of the thyroid influences mature kidney function indirectly by affecting the cardiovascular system and the renal blood flow, and directly by affecting glomerular filtration, electrolyte pumps, the secretory and absorptive capacity of the tubuli, and the structure of the kidney. Hyperthyroidism accelerates several physiologic processes, a fact which is reflected in the decreased systemic vascular resistance, increased cardiac output (CO), increased renal blood flow (RBF), hypertrophic and hyperplastic tubuli, and increased glomerular filtration rate (GFR). Renal failure can progress due to glomerulosclerosis, proteinuria and oxidative stress. Hypothyroidism has a more negative influence on kidney function. Peripheral vascular resistance is increased with intrarenal vasoconstriction, and CO is decreased, causing decreased RBF. The influence on the different tubular functions is modest, although the transport capacity is below normal. The GFR is decreased up to 40% in hypothyroid humans. Despite the negative influences on glomerular and tubular kidney function, a hypothyroid state has been described as beneficial in kidney disease. Kidney disease is associated with decreased thyroid hormone concentrations caused by central effects and by changes in peripheral hormone metabolism and thyroid hormone binding proteins. Geriatric cats form an animal model of disease because both hyperthyroidism and chronic kidney disease (CKD) have high prevalence among them, and the link between thyroid and kidney affects the evaluation of clinical wellbeing and the possible treatment options.