Refining the predictive value of preoperative apparent diffusion coefficient (ADC) by whole-tumor analysis for facial nerve outcomes in vestibular schwannomas

BACKGROUND

Apparent diffusion coefficient (ADC) in MRI has been shown to correlate with postoperative House-Brackmann (HB) scores in patients with vestibular schwannoma despite limited methodology. To rectify limitations of single region of interest (ROI) sampling, we hypothesize that whole-tumor ADC histogram analysis will refine the predictive value of this preoperative biomarker related to postoperative facial nerve function.

METHODS

Of 155 patients who underwent resection of vestibular schwannoma (2014-2020), 125 patients were included with requisite clinical and radiographic data. After volumetric analysis and whole-tumor ADC histogram, regression tree analysis identified ADC cutoff for significant differences in HB grade. Outcomes were extent of resection, facial nerve function, hospital length of stay (LOS), and complications.

RESULTS

Regression tree analysis defined three quantitative ADC groups (× 10-6 mm2/s) as high (> 2248.77; HB 1.7), mid (1468.44-2248.77; HB 3.1), and low (< 1468.44; HB 2.3) range (p 0.04). The mid-range ADC group had significantly worse postoperative HB scores and longer hospital LOS. Large tumor volume was independently predictive of lower rates of gross total resection (p <0.0001), higher postoperative HB score (p 0.002), higher rate of complications (p 0.04), and longer LOS (p 0.003).

CONCLUSIONS

Whole-tumor histogram yielded a robust regression tree analysis that defined three ADC groups with significantly different facial nerve outcomes. This likely reflects tumor heterogeneity better than solid-tumor ROI sampling. Whole-tumor ADC warrants further study as a useful radiographic biomarker in patients with vestibular schwannoma who are considering surgical resection.

Immunocompetent isolated cerebral mucormycosis presenting with obstructive hydrocephalus: illustrative case

BACKGROUND

Isolated cerebral mucormycosis is rare in immunocompetent adults and is only sparsely reported to be associated with obstructive hydrocephalus.

OBSERVATIONS

Here, the authors report a case of obstructive hydrocephalus secondary to central nervous system mucormycosis without other systems or rhino-orbital involvement and its technical surgical management. A 23-year-old, incarcerated, immunocompetent patient with history of intravenous (IV) drug use presented with syncope. Although clinical and radiographic findings failed to elucidate an infectious pathology, endoscopy revealed an obstructive mass lesion at the level of the third ventricle, which, on microbiological testing, was confirmed to be Rhizopus fungal ventriculitis. Perioperative cerebrospinal fluid diversion, endoscopic third ventriculostomy, endoscopic biopsy technique, patient outcomes, and the literature are reviewed here. The patient received intrathecal and IV amphotericin B followed by a course of oral antifungal treatment and currently remains in remission.

LESSONS

The patient's unique presentation and diagnosis of isolated cerebral mucormycosis reveal this pathogen as a cause of ventriculitis and obstructive hydrocephalus in immunocompetent adult patients, even in the absence of infectious sequelae on neuroimaging.

Dilated cardiomyopathy of possible dietary origin in a cat

An 11-year-old spayed female domestic shorthaired cat was diagnosed with severe dilated cardiomyopathy (DCM) and congestive heart failure. The cat had been eating cat foods that were high in pulses (e.g. peas, lentils, chickpeas). Neither plasma nor whole blood taurine concentrations were deficient. Primary treatment included furosemide, pimobendan, and clopidogrel, and changing to diets that did not contain pulses (a taurine supplements was not administered). The cat's clinical signs improved, high-sensitivity cardiac troponin I concentrations decreased, and echocardiographic measurements stayed relatively stable for over one year after initiating cardiac medications and changing the diet. Ultimately, the cat was euthanized for worsening congestive heart failure 374 days after the diagnosis of DCM. Infectious disease testing during the time of clinical surveillance was negative. Routine histopathology of the heart was unremarkable, but electron microscopy of the left ventricle showed large numbers of mitochondria of variable size and structure. A moderate number of lamellar bodies and autophagic vacuoles also were noted. This case report illustrates an unusual case of a cat with DCM unrelated to taurine deficiency. The relative roles of diet change, cardiac medications, and a dedicated owner are unclear, but this cat's relatively long survival time is similar to that seen after diet change in dogs and cats with DCM eating high-pulse diets.

Epidural analgesia and emergency delivery for presumed fetal compromise: post-hoc analysis of RAVEL multicenter randomized controlled trial

OBJECTIVE

To investigate the association between epidural analgesia (EDA) vs patient-controlled remifentanil analgesia (PCRA) and emergency delivery for presumed fetal compromise, in relation to birth-weight quintile.

METHODS

This was a post-hoc per-protocol analysis of the RAVEL multicenter equivalence randomized controlled trial. Non-anomalous singleton pregnancies between 36 + 0 and 42 + 6 weeks' gestation were randomized at the time of requesting pain relief to receive EDA or PCRA. The primary outcome was emergency delivery for presumed fetal compromise. Secondary outcomes included mode of delivery and neonatal outcomes. Analysis was performed according to birth-weight quintile and was corrected for relevant confounding variables.

RESULTS

Of 619 pregnant women, 336 received PCRA and 283 received EDA. Among women receiving EDA, 14.8% had an emergency delivery for presumed fetal compromise, compared with 8.3% of women who received PCRA. After adjusting for parity, women receiving EDA had higher odds of presumed fetal compromise compared to those receiving PCRA (odds ratio, 1.69 (95% CI, 1.01-2.83)). A statistically significant linear-by-linear association was observed between presumed fetal compromise and birth-weight quintile (P = 0.003). The incidence of emergency delivery for presumed fetal compromise was highest in women receiving EDA and delivering a neonate with a birth weight in the lowest quintile.

CONCLUSIONS

Intrapartum EDA is associated with a higher rate of emergency delivery for presumed fetal compromise compared to treatment with PCRA. Birth-weight quintile is a strong predictor of this outcome, independent of pain management method. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Dilated cardiomyopathy in cats: survey of veterinary cardiologists and retrospective evaluation of a possible association with diet

INTRODUCTION/OBJECTIVES

The objectives were to conduct a survey of cardiologists on their recent experiences with cats that have dilated cardiomyopathy (DCM) and to retrospectively review individual cases of feline DCM.

ANIMALS, MATERIALS AND METHODS

Part one: A survey was distributed to cardiologists with questions regarding caseload and clinical management of cats with DCM diagnosed over the past two years. Part two: Cardiologists completing the survey were invited to submit data from cats recently diagnosed with DCM. Data on signalment, clinical signs, diet, echocardiographic measurements and outcome were recorded.

RESULTS

Part one: From 52 completed surveys, many cardiologists responded that measuring and supplementing taurine and recommending a diet change in cats with DCM are common practices. Few (15%) cardiologists reported an increase in the number of feline DCM cases over the past two years, although some had cases that improved even if taurine deficiency was not present. Part two: Twenty of 37 (54%) cats ate low pea/lentil (low PL) diets, and 14/37 (38%) ate high PL diets at the time of diagnosis; three had incomplete diet information. Two of 13 cats (15%) in which taurine was measured had levels below the reference range. After adjusting for other variables, cats eating high PL diets that changed diets after diagnosis had a significantly longer survival time than that of cats eating high PL diets that did not change diets after diagnosis (P = 0.025).

CONCLUSIONS

Additional research is warranted to determine whether there could be a possible association between diet and DCM in cats.

Implications of Celiac Disease Among Patients Undergoing Gastric Bypass

INTRODUCTION

Bariatric surgery is generally safe and effective, but co-existing malabsorptive processes may increase the risk of complications or nutritional deficiencies. Bariatric surgery has not been well studied in the setting of pre-existing celiac disease.

MATERIALS AND METHODS

Patients who underwent Roux-en-Y gastric bypass (RYGB) from January 2002 to December 2015 were retrospectively reviewed for either diagnosis of or serum testing for celiac disease. Identified patients were re-reviewed for adherence to American Gastroenterological Association (AGA) diagnostic criteria. Patient demographics, operative data, and post-operative weight loss and nutritional parameters were collected.

RESULTS

Of the > 12,000 patients who underwent bariatric surgery during this study period, there were 342 patients that had abnormal serology or pathology results. Expert review confirmed three patients (0.8%) with celiac disease diagnosed before RYGB procedure. All were female, with an average age of 33 years and a mean BMI of 44.07 kg/m². At the time of surgery, two of the three patients were following a gluten-free diet. At 6 months follow-up, mean % excess weight loss was 76.5%. The patients following a gluten-free diet preoperatively continued post-operatively. No patients were anemic nor had vitamin B12 or iron deficiencies at 12-month follow-up. Two patients had vitamin D insufficiencies and responded to daily oral supplementation.

CONCLUSION

Though many bariatric patients may carry a presumptive diagnosis of celiac disease, a small percentage of these meet AGA diagnostic criteria. RYGB appears safe in this population with comparable weight loss in non-celiac counterparts. Increased attention to vitamin D levels may be warranted post-operatively.

Association between Survival Time and Changes in NT-proBNP in Cats Treated for Congestive Heart Failure

Background

Reductions in N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) concentrations after treatment have been associated with improved survival in people with congestive heart failure (CHF), but have not been reported in cats with CHF.

Objectives

To evaluate changes in NT‐proBNP concentrations in cats with CHF after treatment and determine whether serial NT‐proBNP measurements provide prognostic information.

Animals

Thirty‐one client‐owned cats.

Methods

Prospective, observational study in cats with new onset CHF secondary to cardiomyopathy. Concentrations of NT‐proBNP were measured within 4 hours of admission to the hospital, on the day of discharge, and at re‐evaluation 7–10 days later.

Results

Median NT‐proBNP concentrations decreased significantly from admission (1,713 pmol/L [range, 160–3,784 pmol/L]) to discharge (902 pmol/L [range, 147–3,223 pmol/L]); P = .005) and from admission to re‐evaluation (1,124 pmol/L [range, 111–2,727 pmol/L]; P = .024). Median survival time was 109 days (range, 1–709 days), with 5 cats still alive at the time of analysis. Cats with a larger percent decrease in NT‐proBNP from admission to discharge had a longer survival time (P = .048). Cats with evidence of active CHF at the time of re‐evaluation (P = .010) and cats whose owners had difficulty administering medications (P = .045) had shorter survival times.

Conclusions and clinical importance

Cats with a larger percent decrease in NT‐proBNP during hospitalization and no evidence of CHF at the time of re‐evaluation had longer survival times. Additional studies are needed to determine whether NT‐proBNP can help guide treatment in cats with CHF.

Evaluation of Weight Loss Over Time in Cats with Chronic Kidney Disease

Background

Thin body condition and weight loss are common in cats with chronic kidney disease (CKD). However, the time course and progression of weight loss before and after diagnosis have not been thoroughly evaluated.

Hypothesis/Objectives

To describe weight loss in cats with CKD before and after diagnosis and its relationship to survival.

Animals

A total of 569 cats (55.5% females and 44.5% males) with CKD from 6 US veterinary practices for which International Renal Interest Society (IRIS) stage, age, date of CKD diagnosis, and at least two body weight measurements were available.

Methods

Body weight measurements were analyzed by time windows and polynomial growth curve analysis. Survival analysis was performed by Kaplan–Meier curves and log‐rank tests.

Results

Median age at diagnosis was 14.9 years (range, 5.0–22.8 years). Cats were categorized at diagnosis as IRIS stage 1 (n = 34 [6%]), stage 2 (n = 345 [61%]), stage 3 (n = 141 [25%]), and stage 4 (n = 49 [9%]). Median body weight at diagnosis was 4.2 kg (range, 1.6–9.9 kg). Cats lost a median of 8.9% of body weight in the 12 months before diagnosis, but weight loss was already present 3 years before diagnosis and accelerated after diagnosis of CKD. Cats <4.2 kg at the time of diagnosis had significantly shorter survival time compared to cats ≥ 4.2 kg at diagnosis (P < .0001).

Conclusions and Clinical Importance

Weight loss can be detected in cats before diagnosis of CKD, accelerates after diagnosis, and is associated with shorter survival. Tracking body weight may help clinicians in earlier diagnosis of CKD.

Association between Body Condition Score and Cancer Prognosis in Dogs with Lymphoma and Osteosarcoma

Background

In humans and rodents obesity appears to promote some cancers by increasing incidence, tumor aggressiveness, recurrence, and fatality. However, the relationship between obesity and cancer in dogs has not been thoroughly evaluated.

Hypothesis/Objectives

Whether body condition score (BCS) at the time of lymphoma (LSA) or osteosarcoma (OSA) diagnosis in dogs is predictive of survival time (ST) or progression‐free interval (PFI). We hypothesized that an overweight body state at the time of cancer diagnosis would be associated with negative outcomes.

Animals

Dogs with LSA (n = 270) and OSA (n = 54) diagnosed and treated between 2000 and 2010.

Methods

Retrospective case review. Signalment, body weight, BCS, cancer diagnosis and treatment, relevant clinicopathologic values, and survival data were collected. Dogs were grouped by BCS (underweight, ideal, and overweight) and ST and PFI were compared.

Results

Overall, 5.5% of dogs were underweight, 54.0% were ideal weight, and 40.4% were overweight at diagnosis. Underweight dogs with LSA had shorter ST (P = .017) than ideal or overweight dogs. BCS was not associated with ST for OSA (P = .474). Progression‐free interval did not differ among BCS categories for either cancer.

Conclusions and Clinical Importance

Obesity was not associated with adverse outcomes among dogs with LSA or OSA in this retrospective study; however, being underweight at the time of diagnosis of LSA was associated with shorter survival. More research is needed to elucidate the relationship between excessive body weight and cancer development and progression in dogs.

Relationship of body size to metabolic markers and left ventricular hypertrophy in cats

BACKGROUND

Cats with hypertrophic cardiomyopathy (HCM) are larger and have higher insulin-like growth factor-1 (IGF-1) concentrations than cats without HCM.

HYPOTHESIS/OBJECTIVES

The aim of this study was to assess echocardiographic findings in a colony of adult cats to determine the relationship between early growth and left ventricular hypertrophy (LVH).

ANIMALS

Twenty-eight neutered adult cats (20 males, 8 females) from a colony ≥ 3 years of age for which growth curves were available.

METHODS

Case-control study. Physical examination and echocardiography were performed, and body weight, body condition score (BCS), and head length and width were measured. Circulating glucose, insulin, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and IGF-1 concentrations were measured and growth data were collected. Stepwise multivariate analyses were performed.

RESULTS

Mean age was 5.2 ± 1.1 years. Current BCSs ranged from 4 to 9 (median, 6) and mean body weight was 4.88 ± 1.29 kg. Variation in body weight was apparent by 6 (mean = 3.26 ± 0.80 kg) and 12 months of age (mean = 4.02 ± 1.02 kg). Cardiac abnormalities included a cardiac murmur (n = 7; 24%), gallop (n = 3; 10%), and arrhythmia (n = 1; 4%). Fourteen of 28 cats (50%) had echocardiographic evidence of LVH. Head width (P = .017), body weight (P < .001), NT-proBNP (P = .023), and IGF-1 (P = .013-.022) were significantly associated with selected measures of LVH.

CONCLUSIONS AND CLINICAL IMPORTANCE

Potential associations between body size, IGF-1, LVH, and HCM warrant future prospective studies.

A randomized study assessing the effect of diet in cats with hypertrophic cardiomyopathy

Background

Diet might influence progression of hypertrophic cardiomyopathy (HCM).

Objective

To investigate whether diet composition could alter clinical, biochemical, or echocardiographic variables in cats with HCM.

Animals

Twenty‐nine cats with HCM (International Small Animal Cardiac Health Council stage 1b) examined at a university teaching hospital.

Methods

Randomized, placebo‐controlled trial. After physical examination, echocardiogram, and blood collection, cats were randomized to 1 of 3 diets, which varied in carbohydrate and fat content and ingredients. Measurements were repeated after 6 months.

Results

There were no significant differences among the 3 groups at baseline. After 6 months, there were no significant changes in the primary endpoints, left ventricular free wall (Group A, P = .760; Group B, P = .475; Group C, P = .066) or interventricular septal thickness in diastole (Group A, P = .528; Group B, P = .221; Group C, P = .097). Group A had significant increases in BUN (P = .008) and cholesterol (P = .021), while Group B had significant increases in BUN (P = .008), cholesterol (P = .007), and triglycerides (P = .005), and significant decreases in NT‐proBNP (P = .013) and hs‐troponin I (P = .043). Group C had significant decreases in body weight (P = .021), left atrial dimension (P = .035), interventricular septal thickness in systole (P = .038), and liver enzymes (P = .034–.038).

Conclusions and Clinical Importance

These data suggest that diet might influence some clinical, biochemical, and echocardiographic variables in cats with HCM.

Cachexia and sarcopenia: emerging syndromes of importance in dogs and cats

Cachexia is the loss of lean body mass (LBM) that affects a large proportion of dogs and cats with congestive heart failure (CHF), chronic kidney disease (CKD), cancer, and a variety of other chronic diseases. Sarcopenia, the loss of LBM that occurs with aging, is a related syndrome, although sarcopenia occurs in the absence of disease. As many of the diseases associated with muscle loss are more common in aging, cachexia and sarcopenia often are concurrent problems. Both cachexia and sarcopenia have important clinical implications because they are associated with increased morbidity and mortality. The pathophysiology of these 2 syndromes is complex and multifactorial, but recent studies have provided new information that has helped to clarify mechanisms and identify potential new targets for treatment. Newly identified mechanisms and pathways that mediate cachexia appear to act by increasing energy requirements, decreasing energy intake, impairing nutrient absorption, and causing metabolic alterations. Whereas cachexia and sarcopenia are important areas of research for drug development in people, they are only beginning to be recognized in veterinary medicine. Greater awareness and earlier diagnosis will help provide practical approaches to managing body weight and lean tissue in dogs and cats, as well as more directed targets for treatment.

Association between body condition and survival in dogs with acquired chronic kidney disease

BACKGROUND

Obesity in people with chronic kidney disease (CKD) is associated with longer survival. The purpose of this study was to determine if a relationship exists between body condition score (BCS) and survival in dogs with CKD.

HYPOTHESIS/OBJECTIVES

Higher BCS is a predictor of prolonged survival in dogs with CKD.

ANIMALS

One hundred dogs were diagnosed with CKD (International Renal Interest Society stages II, III or IV) between 2008 and 2009.

METHODS

Retrospective case review. Data regarding initial body weight and BCS, clinicopathologic values and treatments were collected from medical records and compared with survival times.

RESULTS

For dogs with BCS recorded (n = 72), 13 were underweight (BCS = 1-3; 18%), 49 were moderate (BCS = 4-6; 68%), and 10 were overweight (BCS = 7-9; 14%). For dogs with at least 2 body weights recorded (n = 77), 21 gained weight, 47 lost weight, and 9 had no change in weight. Dogs classified as underweight at the time of diagnosis (median survival = 25 days) had a significantly shorter survival time compared to that in both moderate (median survival = 190 days; P < .001) and overweight dogs (median survival = 365 days; P < .001). There was no significant difference in survival between moderate and overweight dogs (P = .95).

CONCLUSIONS AND CLINICAL IMPORTANCE

Higher BCS at the time of diagnosis was significantly associated with improved survival. Further research on the effects of body composition could enhance the management of dogs with CKD.

Retrospective evaluation of parenteral nutrition in alpacas: 22 cases (2002-2008)

BACKGROUND

Parenteral nutrition is an important method of nutritional support in hospitalized animals, but minimal information has been published on its use in camelids.

HYPOTHESIS/OBJECTIVES

The purpose of this study was to characterize the use of total parenteral nutrition (TPN) in alpacas, evaluate the formulations used, and determine potential complications.

ANIMALS

Twenty-two alpacas hospitalized at the Tufts Cummings School for Veterinary Medicine (site 1: n = 8) and the Ohio State University Veterinary Teaching Hospital (site 2: n = 14).

METHODS

A retrospective analysis of all alpacas that received TPN between 2002 and 2008 was performed to assess clinical indications, clinical and clinicopathologic data, and outcome.

RESULTS

The most common underlying diseases in animals receiving TPN were gastrointestinal dysfunction (n = 16), hepatic disease (n = 2), and neoplasia (n = 2). Several metabolic abnormalities were identified in animals (n = 20/22) before TPN was initiated, including lipemia (n = 12/22), hyperglycemia (11/22), and hypokalemia (n = 11/22). Median age was significantly lower for site 1 cases (0.1 years; range, 0.01-11.0) compared with those from site 2 (4.9 years; range, 0.1-13.7; P = .03). Animals at site 2 also had a longer duration of hospitalization (P = .01) and TPN administration (P = .004), as well as higher survival rate (P < .02). Twenty-one of 22 alpacas developed at least 1 complication during TPN administration. Metabolic complications were most prevalent (n = 21/22) and included hyperglycemia (n = 8/21), lipemia (n = 7/21), hypokalemia (n = 3/21), and refeeding syndrome (n = 3/21).

CONCLUSIONS AND CLINICAL IMPORTANCE

TPN is a feasible method of nutritional support for alpacas when enteral feeding is not possible. Prospective studies are warranted to determine optimal TPN formulations for alpacas.

Relationship among plasma amino acids, C-reactive protein, illness severity, and outcome in critically ill dogs

BACKGROUND

Alterations in circulating amino acids have been documented in animal models and in critically ill people but have not been evaluated in dogs with spontaneously occurring disease.

HYPOTHESIS/OBJECTIVES

To compare amino acid concentrations in critically ill dogs and healthy controls and to investigate potential relationships among amino acids, markers of inflammation, illness severity, and clinical outcome.

ANIMALS

Forty-eight critically ill dogs and 24 healthy control dogs.

METHODS

Plasma was analyzed for amino acids and C-reactive protein (CRP) was measured in serum. The Fischer ratio (the molar ratio of branched chain amino acids [BCAA] to aromatic amino acids [AAA]) and survival prediction index (SPI2) were calculated.

RESULTS

Median CRP concentrations were significantly higher in the critically ill dogs compared with controls (P < .001). Critically ill dogs had significantly lower concentrations of alanine (P= .001), arginine (P < .001), citrulline (P < .001), glycine (P < .001), methionine (P < .001), proline (P < .001), and serine (P= .001) but significantly higher concentrations of lysine (P= .02) and phenylalanine (P < .001; Table 1). This pattern resulted in a significantly lower Fischer ratio (P= .001) in the critically ill group. Median SPI2 score was significantly higher in dogs that survived (P= .03). Concentrations of arginine (P= .02), isoleucine (P= .01), leucine (P= .04), serine (P= .04), valine (P= .04), total BCAA (P= .03), and the Fischer ratio (P= .03) were significantly higher in survivors compared with nonsurvivors.

CONCLUSIONS AND CLINICAL IMPORTANCE

Critically ill dogs have altered amino acid profiles and additional research to investigate potential benefits of amino acid supplementation is warranted.

Echocardiographic ratio indices in overtly healthy Boxer dogs screened for heart disease

BACKGROUND

Boxer dogs are routinely screened by echocardiography to exclude congenital and acquired heart disease. Individuals of a given breed may span a large range of body sizes, potentially invalidating linear regression of M-mode measurements against body weight. Echocardiographic ratio indices (ERIs) provide a novel method of characterizing echocardiographic differences between Boxers and other dog breeds.

HYPOTHESIS

ERIs obtained from overtly healthy Boxer dogs presented for cardiac screening will be different from ERIs established for normal non-Boxer dogs, and those differences will be unrelated to aortic velocity or systolic blood pressure.

ANIMALS

Eighty-one Boxers with no outward clinical signs of heart disease were studied.

METHODS

All dogs were examined by 2-dimensional, M-mode, and Doppler echocardiography. M-mode measurements were used to perform ERI calculations, and the indices in Boxers were compared between Boxers with varying severity of arrhythmia and those of normal non-Boxer dogs.

RESULTS

Differences in weight-based ERIs, which reflect increased thickness of the left ventricular free wall (LVW) and interventricular septum (IVS) and smaller aortic size, were found in overtly healthy Boxer dogs compared with normal non-Boxer dogs. ERIs of left atrial and LV cavity size in overtly healthy Boxers were not significantly different from those of non-Boxer dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

Boxer dogs may have an increased relative thickness of the LVW and IVS that is independent of aortic size, aortic velocity, or arterial blood pressure, and this morphology should be taken into consideration when screening Boxers by echocardiography.

The role of (111)In Capromab Pendetide (Prosta-ScintR) immunoscintigraphy in the management of prostate cancer

(111)In Capromab Pendetide (ProstaScintR) is a whole murine antibody that is reactive with prostate specific membrane antigen (PSMA), a glycoprotein on the surface of normal and abnormal prostate epithelium. It has proven to be of great value in assisting management decisions in prostate cancer patients who initially present with high risk for metastatic spread, or who develop a picture of recurrent disease after surgery or radiation therapy. Patterns of metastatic lymphatic spread have correlated well with autopsy reports in the literature. Unfortunately, other imaging study and/or histologic confirmation of scintigraphic findings has been difficult to obtain. Prostascint's role in predicting durable complete response (DCR) in postoperative patients having salvage radiotherapy to their prostate fossa is very promising. Further investigative work in larger patient populations is needed to confirm these early results.

Enhanced lung scan diagnosis of pulmonary embolism with the use of ancillary scintigraphic findings and clinical correlation

Analysis of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) and modified PIOPED studies has suggested that an experienced observer is capable of more accurate lung scan interpretation than the less experienced individual. This has been attributed to the use of unique Gestalt factors not contained in published diagnostic algorithms, which are acquired through extensive experience in reviewing and interpreting lung scans. How fully these factors can be codified and transmitted to less experienced observers is uncertain; however, there is a large body of published data that attempts to convey fine points of lung scan interpretation, including a large body of ancillary scintigraphic findings and a number of refinements in the application of diagnostic algorithms. Review of these factors will accelerate the training of less experienced readers. Finally, an understanding of lung scan language and an appreciation of clinically relevant factors, particularly pretest probability, will maximize the reader's ability to use the lung scan in managing patients who are suspected of having pulmonary embolic disease.

Neuronal size in the spinal nucleus of the bulbocavernosus: direct modulation by androgen in rats with mosaic androgen insensitivity

The motoneurons of the spinal nucleus of the bulbocavernosus (SNB) and its target muscles, the bulbocavernosus and levator ani, form a sexually dimorphic circuit that is developmentally dependent on androgen exposure and exhibits numerous structural and functional changes in response to androgen exposure in adulthood. Castration of male adult rats causes shrinkage of SNB somata, and testosterone replacement reverses this effect, but the site at which androgen is acting to cause this change is undetermined. We exploited the X-chromosome residency of the androgen receptor (AR) gene to generate androgenized female rats that were heterozygous for the testicular feminization mutant (tfm) AR mutation and that, as a consequence of ontogenetic random X-inactivation, expressed a blend of androgen-sensitive wild-type cells and tfm-affected androgen-insensitive cells in the SNB. Chronic testosterone treatment of adult mosaics increased soma sizes only in androgen-competent wild-type SNB cells. The size of tfm-affected SNB somata in the same animals did not differ from the size of either the wild-type or tfm-affected SNB neurons in control mosaics that did not receive androgen treatment in adulthood. Because the muscle targets of the SNB are known to be uniformly androgen-sensitive in tfm mosaics, this mosaic analysis provides unambiguous evidence that androgenic effects on motoneuron soma size are mediated locally in the SNB. It is possible that the neuronal AR plays a permissive role in coordinating the actions of androgen.

Prevalence and prognostic importance of hypomagnesemia and hypocalcemia in horses that have colic surgery

OBJECTIVE

To determine the prevalence of hypomagnesemia and hypocalcemia in horses with surgical colic.

ANIMALS

35 horses with surgically managed colic.

PROCEDURE

Serum concentrations of total magnesium (tMg2+) and calcium (tCa2+), as well as ionized magnesium (iMg2+) and calcium (iCa2+) were analyzed before surgery and 1, 3, 5, and 7 days following surgery. A lead-II ECG and pertinent clinical data were also obtained at each time.

RESULTS

Preoperative serum tMg2+ and iMg2+ concentrations were below the reference range in 6 (17%) and 19 (54%) horses, respectively. Serum concentrations of tCa2+ and iCa2+ were less than the reference range in 20 (57%) and 30 (86%) horses before surgery. Horses with strangulating lesions of the gastrointestinal tract had significantly lower preoperative serum concentrations of iMg2+ and iCa2+, as well as a higher heart rate than horses with nonstrangulating lesions. Horses that developed postoperative ileus had significantly lower serum concentrations of iMg2+ after surgery. Serum concentrations of magnesium and calcium (total and ionized) correlated significantly with the PR, QRS, QT, and corrected QT (QTc) intervals. Horses that were euthanatized at the time of surgery (n = 7) had significantly lower preoperative serum concentrations of iMg2+, compared with horses that survived. Neither serum magnesium nor calcium concentrations were predictors of hospitalization time or survival.

CONCLUSIONS AND CLINICAL RELEVANCE

Hypomagnesemia and hypocalcemia were common during the perioperative period, particularly in horses with strangulating intestinal lesions and ileus. Serum concentrations of tMg2+ and tCa2+ were less sensitive than iMg2+ and iCa2+ in detecting horses with hypomagnesemia and hypocalcemia.

Use of western immunoblot for evaluation of myocardial dystrophin, alpha-sarcoglycan, and beta-dystroglycan in dogs with idiopathic dilated cardiomyopathy

OBJECTIVE

To evaluate the potential importance of dystrophin, alpha-sarcoglycan (adhalin), and beta-dystroglycan, by use of western blot analysis, in several breeds of dogs with dilated cardiomyopathy.

SAMPLE POPULATION

Myocardial samples obtained from 12 dogs were evaluated, including tissues from 7 dogs affected with dilated cardiomyopathy, 4 control dogs with no identifiable heart disease (positive control), and 1 dog affected with Duchenne muscular dystrophy (negative control for dystrophin). Of the affected dogs, 4 breeds were represented (Doberman Pinscher, Dalmatian, Bullmastiff, and Irish Wolfhound).

PROCEDURE

Western blot analysis was used for evaluation of myocardial samples obtained from dogs with and without dilated cardiomyopathy for the presence of dystrophin and 2 of its associated glycoproteins, alpha-sarcoglycan and beta-dystroglycan.

RESULTS

Detectable differences were not identified between dogs with and without myocardial disease in any of the proteins evaluated.

CONCLUSIONS AND CLINICAL RELEVANCE

Abnormalities in dystrophin, alpha-sarcoglycan, and beta-dystroglycan proteins were not associated with the development of dilated cardiomyopathy in the dogs evaluated in this study. In humans, the development of molecular biological techniques has allowed for the identification of specific causes of dilated cardiomyopathy that were once considered to be idiopathic. The use of similar techniques in veterinary medicine may aid in the identification of the cause of idiopathic dilated cardiomyopathy in dogs, and may offer new avenues for therapeutic intervention.

Relationship between circulating and dietary taurine concentrations in dogs with dilated cardiomyopathy

A retrospective study was conducted to determine dietary taurine concentrations in dogs with dilated cardiomyopathy (DCM) and to compare the clinical outcome of taurine-deficient and non-taurine-deficient dogs. Taurine concentrations were low in blood samples from 20 of 37 dogs with DCM. Median dietary taurine concentration was not significantly different between taurine-deficient and nondeficient dogs. There was no correlation between dietary and circulating taurine concentrations. The outcome of taurine-deficient dogs supplemented with taurine was not different from the outcome of nondeficient dogs. The role oftaurine and its relationship to dietary intake in canine DCM remain unclear.

Perinatal organization of a sexually dimorphic aromatase enzyme-containing immunoreactive nucleus

Sexual dimorphisms have been identified in the brains of many vertebrates. The adult musk shrew brain contains a sexually dimorphic nucleus of aromatase (AROM) immunoreactive (ir) neurons within the medial preoptic area (mPOA). This cell group is larger and contains more neurons in males than in females. We examined the effects of perinatal hormone manipulations on the organization of this nucleus. Administration of testosterone (T) to female pups (days 1-5 postnatal) increased the size of the AROM-ir nucleus. Males castrated on postnatal day 1 had a smaller AROM-ir nucleus as adults than did males that remained gonadally intact during development. These data show that T and/or its estrogenic metabolite act during an early critical period to organize the development of AROM-ir neurons in the mPOA.

Plasma homocysteine, B vitamins, and amino acid concentrations in cats with cardiomyopathy and arterial thromboembolism

Arterial thromboembolism (ATE) is a common complication of cats with cardiomyopathy (CM), but little is known about the pathophysiology of ATE. In people, high plasma concentrations of homocysteine and low B vitamin concentrations are risk factors for peripheral vascular disease. In addition, low plasma arginine concentrations have been linked to endothelial dysfunction. The purpose of this study was to compare concentrations of homocysteine, B vitamins, and amino acids in plasma of normal cats to those of cats with CM and ATE. Plasma concentrations of homocysteine, vitamin B6, vitamin B12, folate, and amino acids were measured in 29 healthy cats, 27 cats with CM alone, and 28 cats with both CM and ATE. No differences were found between groups in homocysteine or folate. Mean vitamin B12 concentration (mean +/- standard deviation) was lower in cats with ATE (866 +/- 367 pg/mL) and cats with CM (939 +/- 389 pg/mL) compared with healthy controls (1,650 +/- 700 pg/mL; P < .001). Mean vitamin B6 concentration was lower in cats with ATE (3,247 +/- 1.215 pmol/mL) and cats with CM (3,200 +/- 906 pmol/mL) compared with healthy control animals (4,380 +/- 1,302 pmol/mL; P = .005). Plasma arginine concentrations were lower in cats with ATE (75 +/- 33 nmol/mL) compared with cats with CM (106 +/- 25 nmol/mL) and healthy control animals (96 +/- 25 nmol/ mL; P < .001). Vitamin B12 concentration was significantly correlated with left atrial size. We interpret the results of this study to suggest that vitamin B12 and arginine may play a role in CM and ATE of cats.

Clinical, echocardiographic, and neurohormonal effects of a sodium-restricted diet in dogs with heart failure

The use of low-sodium diets in dogs with heart failure is common practice, but randomized, double-blind studies have not been conducted to examine the benefits or problems with this approach. The purpose of this study was to determine the effects of a low-sodium diet on clinical, echocardiographic, and neurohormonal parameters in dogs with heart failure. Dogs with stable chronic heart failure were fed exclusively a low-sodium (LS) and a moderate-sodium (MS) diet for 4 weeks each in a randomized, double-blind, crossover design. At days 0, 28, and 56, echocardiography and thoracic radiography were performed, and blood was analyzed for electrolytes and neurohormones. Fourteen dogs completed the study (9 with chronic valvular disease and 5 with dilated cardiomyopathy). Electrolyte abnormalities were common during the study, and serum sodium and chloride concentrations decreased significantly on the LS diet. Neurohormones did not change significantly between diet groups. Maximum left atrial (P = .05) and standard left atrial (P = .09) size decreased on the LS diet. For dogs with chronic valvular disease, vertebral heart score (P = .05), left ventricular internal dimension in diastole (P = .006) and systole (P = .02), standard left atrial dimension (P = .03), maximum left atrial dimension (P = .02), end-diastolic volume index (P = .02), and end-systolic volume index (P = .04) decreased significantly on the LS diet compared to the MS diet. Although analysis of these data suggests some benefits of a low-sodium diet, future studies with improved study design are needed to further evaluate the advantages and disadvantages of sodium restriction in dogs with heart failure.

Lymphoscintigraphy demonstrating thoracic duct injury in an infant with hypoplastic left heart syndrome

Chylous effusion is an infrequent complication of cardiothoracic surgery and a less frequent complication of central line placement. The authors describe a novel application of lymphoscintigraphy showing thoracic duct injury in an infant after surgery for hypoplastic left heart syndrome.

Scintigraphic findings in peroneal tendonitis: a case report

A case report of radionuclide bone scan findings in a patient with peroneus brevis tendonitis is presented. Peroneal tendonopathy is a common cause of lateral ankle pain. Although magnetic resonance imaging (MRI) findings have been described in the literature, we know of no other detailed report of three-phase bone scan findings, which we believe can provide an alternate means to diagnose this condition. The positive findings consist of a curvilinear band of increased activity that corresponded to the anatomic position of the peroneus brevis tendon and was detected only on the first two phases of the study.

Radionuclide renal scan findings in rupture of the ureter: a case report

Radionuclide renal scan findings in a patient with iatrogenic rupture of the ureter are reported. Although the literature contains reports of the radionuclide scan in rupture of the ureter from other causes, this, to our knowledge is the first description of the scan findings in iatrogenic rupture.

Survival and failure to thrive in the SIV-infected juvenile rhesus monkey

In AIDS patients, wasting in adults and failure to thrive in children are common and devastating problems. Weight loss in rhesus macaques infected with simian immunodeficiency virus (SIV) has not been well characterized. The purpose of this study was to determine growth curves in SIV-infected juvenile macaques to determine the effects of SIV infection on body weight and growth. Medical records of seven juvenile male SIV-infected macaques were retrospectively reviewed to determine body weights, survival time, CD4 count, and viral load. Mean age and body weight at the time of inoculation were 63.3 weeks and 2.4 kg, respectively. Mean survival was 73.7 weeks, and mean body weight at the time of death was 3.0 kg, whereas the published mean body weight for this age of male rhesus macaque is 4.1 kg. Compared with the linear growth pattern of normal animals, the growth pattern for the SIV-infected animals exhibited strong nonlinearity with an inflection point at the mean survival of 74 weeks. After this time point, the discrepancy between growth curves for infected and healthy animals increased at a greater rate. Body weight correlated inversely with viral load (r = -0.368; p = .003) but there was no correlation between body weight and CD4 count. The results of this study suggest that failure to thrive is a consequence of SIV infection and may be related to severity of infection.

Assessment of degree of oxidative stress and antioxidant concentrations in dogs with idiopathic dilated cardiomyopathy

OBJECTIVE

To assess degree of oxidative stress and antioxidant concentrations in dogs with idiopathic dilated cardiomyopathy (IDCM).

DESIGN

Prospective study.

ANIMALS

18 dogs with IDCM and 16 healthy control dogs.

PROCEDURE

Concentrations of malondialdehyde (an indicator of oxidative stress); vitamins A, C, and E; glutathione peroxidase; and superoxide dismutase were measured.

RESULTS

Glutathione peroxidase concentration was significantly increased in dogs with IDCM, compared with control dogs. Vitamin A and superoxide dismutase concentrations were not significantly different between groups. A negative correlation was found between disease severity and plasma vitamin E concentration. Disease severity was not correlated with concentrations of other antioxidants. Medications did not significantly affect oxidant or antioxidant concentrations.

CONCLUSIONS AND CLINICAL RELEVANCE

The change in glutathione peroxidase concentration and the correlation between vitamin E concentration and disease severity suggest that the oxidant-antioxidant system may play a role in development of IDCM.

Factors contributing to the decision for euthanasia of dogs with congestive heart failure

OBJECTIVE

To determine the prevalence of clinical signs that affect quality of life in dogs with congestive heart failure (CHF), and to characterize the role of these clinical signs in the decision for euthanasia.

DESIGN

Prospective study.

ANIMALS

38 dogs with CHF that had been euthanatized within the preceding 22 months.

PROCEDURE

Clinical information and factors affecting the decision for euthanasia were reviewed and recorded from medical records of dogs with CHF. Each owner was then interviewed via telephone to determine whether their dog had anorexia or other clinical signs of disease prior to euthanasia, their perception of their dogs' quality of life, and the most important factor and contributing factors that influenced the decision to euthanatize their dog.

RESULTS

Of the 38 dogs with CHF, > 70% had weakness (35 dogs), coughing (33), anorexia (32), weight loss (32), dyspnea (30), or exercise intolerance (28) reported by their owners. Factors often named by owners as most important in the decision for euthanasia were poor prognosis given by the attending veterinarian, recurrent clinical signs of CHF (ie, coughing, dyspnea, or ascites), and poor quality of life. Weakness, anorexia, and recurrent clinical signs of CHF were the most common contributing factors in the decision for euthanasia.

CLINICAL IMPLICATIONS

Anorexia, weight loss, and exercise intolerance are common in dogs euthanatized because of CHF. The importance of quality of life and poor prognosis in making a decision for euthanasia suggests that addressing these factors may improve patient management.

Neonatal androgen affects copulatory behavior in the female musk shrew

The role of neonatal testosterone in the development of copulatory behavior was examined in an insectivore, the musk shrew (Suncus murinus). Female musk shrews were treated with testosterone propionate (TP) for the first 5 days of life and then tested in adulthood for either female or male-like copulatory behavior. Early TP had a masculinizing effect; neonatally treated animals mounted a stimulus female more frequently, and with shorter latencies, in response to adult testosterone treatment than did control females. Neonatally androgenized females also showed deficits in female sexual behavior; few received ejaculations from stud males. This difference was likely caused by increased aggression exhibited by the neonatally TP-treated females toward males. In turn, female aggression decreased efficiency of male partners' intromission attempts. Early TP treatments also caused structural abnormalities in the ovaries, but did not effect their capacity to ovulate in response to either gonadotropin-releasing hormone or human chorionic gonadotropin injection. In sum, exposure to TP during development augmented display of male-like behavior in females and had subtle deleterious effects on expression of feminine behavior.

Interventional nutrition for cardiac disease

Animals with cardiac disease can have a variety of nutritional alterations for which interventional nutrition can be beneficial. Deviation from optimal body weight, both obesity and cachexia, is a common problem in cardiac patients and adversely affects the animal. Methods for maintaining optimal weight are important for good quality of life in dogs and cats with cardiac disease. Providing proper diets to prevent excess intake of sodium and chloride also is important, but severe salt restriction may not be necessary until later stages of disease. Certain nutrient deficiencies may play a role in the pathogenesis or complications of cardiac disease, but nutrients also may have effects on cardiac disease which are above and beyond their nutritional effects (nutritional pharmacology). Supplementation of nutrients such as taurine, carnitine, coenzyme Q10, and omega-3 polyunsaturated fatty acids may have benefits in dogs or cats with cardiac disease through a number of different mechanisms. By addressing each of these areas maintaining optimal weight, avoiding nutritional deficiencies and excesses, and providing the benefits of nutritional pharmacology, optimal patient management can be achieved.

Nutritional alterations and the effect of fish oil supplementation in dogs with heart failure

Alterations in body composition and nutritional status are common in humans with heart failure and are related, in part, to increases in cytokine concentrations. Cytokines have not been studied previously in dogs with naturally occurring cardiac disease nor has fish oil administration been used in this population to decrease cytokine production. The purposes of this study were to characterize nutritional and cytokine alterations in dogs with heart failure and to test the ability of fish oil to reduce cytokines and improve clinical outcome. Body composition, insulinlike growth factor-1, fatty acids, and cytokines were measured in 28 dogs with heart failure and in 5 healthy controls. Dogs with heart failure then were randomized to receive either fish oil or placebo for 8 weeks. All parameters were measured again at the end of the study period. At baseline, 54% of dogs with heart failure were cachectic and the severity of cachexia correlated with circulating tumor necrosis factor-alpha concentrations (P = .05). Cytokine concentrations at baseline, however, were not significantly increased in dogs with heart failure compared to controls. Baseline plasma arachidonic acid (P = .02), eicosapentaenoic acid (P = .03), and docosahexaenoic acid (P = .004) concentrations were lower in dogs with heart failure than in controls. Fish oil supplementation decreased interleukin-1 beta (IL-1) concentrations (P = .02) and improved cachexia (P = .01) compared to the placebo group. The mean caloric intake of the heart failure dogs as a group was below the maintenance energy requirement (P < .001), but no difference was found in food intake between the fish oil and placebo groups. Insulinlike growth factor-1 concentrations (P = .01) and reductions in circulating IL-1 concentrations over the study period (P = .02) correlated with survival. These data demonstrate that canine heart failure is associated with cachexia, alterations in fatty acids, and reduced caloric intake. Fish oil supplementation decreased IL-1 concentrations and improved cachexia. In addition, reductions in IL-1 predicted survival, suggesting that anticytokine strategies may benefit patients with heart failure.

The use of enalapril in the treatment of feline hypertrophic cardiomyopathy

The clinical response to enalapril in 19 cats with hypertrophic cardiomyopathy (HCM) was evaluated retrospectively. Eleven cats were in congestive heart failure (CHF) at the time enalapril was prescribed, while only one cat was in CHF when the cats were reexamined three-to-six months later. Significant changes in cardiac dimensions were identified echocardiographically. No adverse effects on blood pressure, serum creatinine, or potassium were noted. Although the preliminary data suggests that enalapril is well tolerated and may contribute to some improvements in cats with HCM, controlled, prospective studies are needed to prove the efficacy of enalapril in this disease.

Magnesium status and the effect of magnesium supplementation in feline hypertrophic cardiomyopathy

Magnesium deficiency has been associated with the development of cardiovascular disease in several species. Cats may be predisposed to alterations in magnesium status because of recent changes in the composition of commercial feline diets. The purposes of this study were 1) to examine the dietary history of cats with hypertrophic cardiomyopathy (HCM), 2) to study magnesium status of cats with HCM compared to normal cats, and 3) to determine the effects of magnesium supplementation in cats with HCM. In part 1 of the study, diets of 65 cats with HCM were examined retrospectively. Forty of the 45 cats for which diets could be determined (89%) ate a diet designed to be magnesium-restricted and/or to produce an acidic urine. In part 2 of the study, 10 cats with HCM were compared to 10 healthy control cats for serum creatinine and magnesium; urine creatinine and magnesium, urine specific gravity and pH, and fractional excretion of magnesium. Urine creatinine and specific gravity were higher in control cats than in cats with HCM. No other differences were found between the 2 groups. In part 3, cats with HCM were supplemented with either 210 mg magnesium chloride (n = 15) or 210 mg lactose (n = 15) for 12 wk. No differences between the 2 groups were found for changes in either magnesium status or echocardiographic parameters. However, the 30 cats with HCM, as a group, did show significant improvements in measures of cardiac hypertrophy over the 12-week period. This was likely the result of treatment with other medications, rather than the magnesium supplementation. The results of this study suggest that cats with HCM are likely to be fed magnesium-restricted diets, but that they do not appear to have altered magnesium status compared to healthy controls.