Steven L. Marks

Prevalence and classification of chronic kidney disease in cats randomly selected from four age groups and in cats recruited for degenerative joint disease studies

Chronic kidney disease (CKD) and degenerative joint disease are both considered common in older cats. Information on the co-prevalence of these two diseases is lacking. This retrospective study was designed to determine the prevalence of CKD in two cohorts of cats: cats randomly selected from four evenly distributed age groups (RS group) and cats recruited for degenerative joint disease studies (DJD group), and to evaluate the concurrence of CKD and DJD in these cohorts. The RS group was randomly selected from four age groups from 6 months to 20 years, and the DJD group comprised cats recruited to four previous DJD studies, with the DJD group excluding cats with a blood urea nitrogen and/or serum creatinine concentration >20% (the upper end of normal) for two studies and cats with CKD stages 3 and 4 for the other two studies. The prevalence of CKD in the RS and DJD groups was higher than expected at 50% and 68.8%, respectively. CKD was common in cats between 1 and 15 years of age, with a similar prevalence of CKD stages 1 and 2 across age groups in both the RS and DJD cats, respectively. We found significant concurrence between CKD and DJD in cats of all ages, indicating the need for increased screening for CKD when selecting DJD treatments. Additionally, this study offers the idea of a relationship and causal commonality between CKD and DJD owing to the striking concurrence across age groups and life stages.

The prevalence of albuminuria in dogs and cats in an ICU or recovering from anesthesia

OBJECTIVE To evaluate the prevalence of albuminuria in dogs and cats admitted to the ICU or recovering from an anesthetic event. DESIGN Prospective clinical study over a 10-week period in 2003. SETTING Veterinary teaching hospital. ANIMALS One hundred and five dogs and 22 cats. INTERVENTIONS Urine was collected from dogs and cats admitted to the ICU or recovering from an anesthetic event. When possible, a second urine sample was collected approximately 48 hours later from those animals that had albuminuria during the initial screening. MEASUREMENTS AND MAIN RESULTS All dog samples and most cat samples were screened for albumin using a commercial point-of-care immunoassay. Aliquots of samples that tested positive were stored at -20 °C until subsequent albumin quantification via antigen capture ELISA. Albuminuria was detected in 63 of 105 (60.0%) dogs and in 14 of 22 (63.6%) cats; the prevalence was higher in animals admitted to ICU than in those recovering from anesthesia. In subsequent samples from 26 dogs, urine albumin decreased in 20 (76.9%) when compared with the first sample; urine albumin was undetectable in 5 (19.2%). In subsequent samples from 6 cats, 4 (66.7%) had decreases in urine albumin when compared with the first sample; 1 (16.7%) was negative for urine albumin. Eleven of 12 dogs (91.7%) and 3 of 4 cats (75%) that died within 3 days of admission to the ICU had abnormal urine albumin; whereas 52 of 93 (55.9%) and 11 of 18 (61.1%) dogs and cats, respectively, who survived more than 3 days had abnormal urine albumin. Dogs with albuminuria were at increased risk of death. CONCLUSIONS The prevalence of albuminuria in animals admitted to the ICU or recovering from anesthesia is higher than reported previously and transient in some patients. The presence of albuminuria may be a negative prognostic indicator in this population.

Thrombi in the trachea of a dog secondary to placement of a tracheotomy tube.

CASE DESCRIPTION A 7-year-old Spaniel-crossbreed dog was evaluated for stertorous breathing and inspiratory stridor. CLINICAL FINDINGS A temporary tracheotomy tube was placed prior to referral. Results of physical examination at our facility, including thoracic auscultation, were unremarkable. Examination of the larynx revealed a 2 x 2-cm nodular mass on the lateral aspect of the epiglottis and left arytenoid cartilage. Cytologic examination of the mass indicated septic suppurative inflammation and intracellular rod-shaped bacteria. During the procedures, decreased air movement through the temporary tracheotomy tube was detected, and the tube was replaced. A thrombus was found on the distal end of the temporary tracheotomy tube; the thrombus obstructed 90% of the tube lumen. Approximately 12 hours later, auscultation revealed decreased sounds in all lung fields. Cervical and thoracic radiography revealed an intraluminal soft tissue opacity distal to the tracheotomy tube. A thrombus that contained hair and plant material was removed from the trachea by use of an embolectomy catheter and videogastroscope. Approximately 30 hours after removal of the initial thrombus, the dog had an episode of respiratory distress. Cervical radiography revealed another intraluminal opacity. It was another thrombus, which also was removed by use of the videogastroscope. TREATMENT AND OUTCOME Tracheoscopy was performed with a videogastroscope in an attempt to remove the thrombi. A Fogarty catheter was used to remove the initial intraluminal thrombus from the trachea. CLINICAL RELEVANCE Airway obstruction resulting from an intraluminal thrombus in the trachea should be considered as a secondary complication after tracheotomy tube placement.

Presumptive intraperitoneal envenomation resulting in hemoperitoneum and acute abdominal pain in a dog.

Objective To describe the clinical features, diagnostic findings, treatment, and outcome of a dog with acute abdominal pain and hemoperitoneum secondary to a presumptive intraperitoneal (IP) snakebite. Case Summary A 10-month-old castrated male mixed-breed dog was evaluated for suspected snake envenomation. The dog presented recumbent and tachycardic with signs of severe abdominal pain. Two cutaneous puncture wounds and hemoperitoneum were discovered during evaluation. Ultrasonographic examination revealed communication of the wounds with the peritoneal cavity. The dog was treated with supportive care, parenteral analgesia, packed red blood cell and fresh frozen plasma transfusions, crotalid antivenom, and placement of an IP catheter to provide local analgesia. The dog recovered fully and was discharged 5 days after initial presentation. New or Unique Information Provided To our knowledge, this is the first report of IP envenomation accompanied by hemorrhage treated with continuous IP analgesia in the veterinary literature.

Evaluation of a point‐of‐care anticoagulant rodenticide test for dogs

OBJECTIVE To evaluate a point-of-care anticoagulant rodenticide lateral flow analyzer for the detection of various rodenticide compounds. DESIGN Prospective, laboratory study. SETTING University teaching hospital. ANIMALS The study utilized a serum sample from one healthy canine donor. Samples were centrifuged and serum samples were aliquoted and either used within 4 hours or frozen at -70°C for further quantitative analysis. INTERVENTIONS Samples were spiked with clinically relevant concentrations of 1 of 6 rodenticide compounds (warfarin, pindone, chlorphacinone, brodifacoum, bromethalin, and its metabolite desmethylbromethalin). Seventy-five microliters of spiked serum (or unaltered serum) was introduced into the lateral flow test. MEASUREMENTS AND MAIN RESULTS Three readers who were blinded to the sample preparation interpreted the lateral flow test as either positive or negative for the presence of anticoagulant rodenticide. All readers were in agreement for the results of each serum sample. The point-of-care test kit was able to detect a single anticoagulant rodenticide (warfarin) at concentrations below the manufacturers recommended limit of detection, but was unable to detect any other anticoagulant rodenticide. CONCLUSIONS The results of this test and therapeutic interventions must be considered in light of history, physical examination, and other clinical data. Based on results from this study, the test kit only detects warfarin and not other more common second-generation anticoagulant rodenticides.Objective To evaluate a point-of-care anticoagulant rodenticide lateral flow analyzer for the detection of various rodenticide compounds. Design Prospective, laboratory study. Setting University teaching hospital. Animals The study utilized a serum sample from one healthy canine donor. Samples were centrifuged and serum samples were aliquoted and either used within 4 hours or frozen at −70°C for further quantitative analysis. Interventions Samples were spiked with clinically relevant concentrations of 1 of 6 rodenticide compounds (warfarin, pindone, chlorphacinone, brodifacoum, bromethalin, and its metabolite desmethylbromethalin). Seventy-five microliters of spiked serum (or unaltered serum) was introduced into the lateral flow test. Measurements and Main Results Three readers who were blinded to the sample preparation interpreted the lateral flow test as either positive or negative for the presence of anticoagulant rodenticide. All readers were in agreement for the results of each serum sample. The point-of-care test kit was able to detect a single anticoagulant rodenticide (warfarin) at concentrations below the manufacturers recommended limit of detection, but was unable to detect any other anticoagulant rodenticide. Conclusions The results of this test and therapeutic interventions must be considered in light of history, physical examination, and other clinical data. Based on results from this study, the test kit only detects warfarin and not other more common second-generation anticoagulant rodenticides.

Feasibility of flotation concentration of fungal spores as a method to identify toxigenic mushrooms

Purpose Mushroom poisoning is a recurring and challenging problem in veterinary medicine. Diagnosis of mushroom exposure in animals is hampered by the lack of rapid diagnostic tests. Our study evaluated the feasibility of using flotation concentration and microscopic evaluation of spores for mushroom identification. Evaluation of this method in living animals exposed to toxigenic mushrooms is limited by ethical constraints; therefore, we relied upon the use of an in vitro model that mimics the oral and gastric phases of digestion. Methods In our study, mycologist-identified toxigenic (poisonous) and nontoxigenic fresh mushrooms were collected in North Carolina, USA. In phase 1, quantitative spore recovery rates were determined following magnesium sulfate, modified Sheather’s sugar solution, and zinc sulfate flotation (n=16 fungal species). In phase 2, mushrooms (n=40 fungal species) were macerated and digested for up to 2 hours in a salivary and gastric juice simulant. The partially digested material was acid neutralized, filtered, and spores concentrated using zinc sulfate flotation followed by microscopic evaluation of spore morphology. Results Mean spore recovery rates for the three flotation fluids ranged from 32.5% to 41.0% (P=0.82). Mean (± standard error of the mean) Amanita spp. spore recovery rates were 38.1%±3.4%, 36.9%±8.6%, and 74.5%±1.6% (P=0.0012) for the magnesium sulfate, Sheather’s sugar, and zinc sulfate solutions, respectively. Zinc sulfate flotation following in vitro acid digestion (phase 2) yielded spore numbers adequate for microscopic visualization in 97.5% of trials. The most common spore shapes observed were globose, spiked, elliptical, smooth and reticulate. Conclusion Flotation can concentrate mushroom spores; however, false negative results can occur. Spore morphology could not be used to differentiate species of mushroom-forming fungi since the spore shape and surface characteristics seen in the present study were often observed with multiple species of mushroom-forming fungi.