To determine clinical characteristics, clinicopathologic data, and bacterial culture and antimicrobial susceptibility results associated with septic arthritis in foals ≤ 180 days old.Retrospective case series.83 foals with septic arthritis.Medical records at 2 teaching hospitals between 1998 and 2013 were searched to identify those for foals ≤ 180 days old with confirmed infection of ≥ 1 synovial structure. Data extracted from the records included signalment, clinicopathologic information, bacteriologic culture and antimicrobial susceptibility results, and outcome. Data were analyzed for all foals as a single population and for foals stratified into 3 age groups (≤ 7 days, 8 to 30 days, and 31 to 180 days).Mean ± SD age of all foals was 18.2 ± 25 days (range, 0 to 180 days). The median number of joints affected per foal was 2 (range, 1 to 10 joints). Forty-seven of 83 (56.6%) foals survived to discharge from the hospital. Seventy antemortem synovial fluid samples underwent bacteriologic culture, of which 60 (85.7%) yielded growth. Of the 72 bacterial isolates identified, 45 (62.5%) were gram negative and 27 (375%) were gram positive. Survival rate was positively associated with plasma fibrinogen concentration and negatively associated with number of affected joints.Results indicated the frequency with which certain bacterial agents were isolated from septic joints, which may be beneficial for the empirical treatment of septic arthritis in foals. Also, the positive association between survival rate and plasma fibrinogen concentration may have prognostic value in a clinical setting.
Abstract Objective —To evaluate baseline plasma cortisol and ACTH concentrations and responses to low-dose ACTH stimulation testing in ill foals. Design —Cross-sectional study. Animals —58 ill foals. Procedures —Baseline cortisol and ACTH concentrations and cortisol concentrations after administration of a low dose of cosyntropin were determined within 6 hours after admission. Foals were assigned to 4 groups on the basis of age (≤ 24 hours vs 1 to 56 days) and presence of septicemia (yes vs no). Values were compared among groups and with values previously reported for healthy foals. Results —Plasma cortisol concentrations 30 and 60 minutes after cosyntropin administration in foals ≤ 24 hours old were significantly higher than corresponding cortisol concentrations in older foals. In all 4 groups, plasma cortisol concentration 30 minutes after cosyntropin administration was significantly higher than baseline cortisol concentration or concentration 60 minutes after cosyntropin administration. No differences in baseline cor-tisol or ACTH concentration or in the ACTH-to-cortisol ratio were detected between groups or when ill foals were compared with healthy foals. A small number of ill foals had low baseline cortisol and ACTH concentrations or low responses to cosyntropin administration, compared with healthy foals. Conclusions and Clinical Relevance —Results indicated that most ill foals in the present study population had adequate responses to cosyntropin administration. However, a small subset of ill foals appeared to have dysfunction of the hypothalamic-pituitary-adrenal axis.
Summary A 12‐year‐old Arabian gelding was presented for severe, rapid weight loss and polyuria. Physical examination revealed a body condition score of 1/9 with severe muscle wasting, moderate tachycardia, profound hyperglycaemia and hypertriglyceridaemia. The horse's clinical condition deteriorated rapidly resulting in euthanasia 16 h following admission. Post‐mortem examination revealed multifocal nests of neoplastic endocrine cells within the liver which had immuno‐positive glucagon reactivity. Based on the combination of cachexia, marked hyperglycaemia and glucagon‐positive neoplastic cells, a diagnosis of malignant glucagonoma, which was presumed to be functional, was made. This is the first case of malignant glucagonoma to be reported in horses.
Summary Tracheal collapse is an uncommon clinical disorder in horses but when present can be difficult to correct. Various medical and surgical procedures to correct tracheal collapse have been described in horses with variable success. Recently, the use of an intraluminal stent has been described as a treatment for tracheal collapse in a miniature horse. The long‐term management, utilising intraluminal stents, in 2 miniature horses with tracheal collapse is presented here. In particular, various complications as a result of intraluminal stent placement are described, the most persistent being the formation of granulation tissue at various regions of the stents. Multiple methods of combating granulation tissue in this situation also are discussed.
Summary Perforation of the oesophagus is an uncommon event that can occur for a variety of reasons. While cervical ruptures of the oesophagus can be managed successfully, intrathoracic lesions warrant a far worse prognosis. Intrathoracic rupture of the oesophagus can occur spontaneously, with no known history of oesophageal obstruction, and may not be identified until a septic pleuropneumonia develops. This report describes the history, clinical presentation, response to therapy and outcome of 5 cases of intrathoracic oesophageal perforation and secondary septic pleuropneumonia.
Summary Bacterial meningitis in the mature horse is a rare and typically fatal condition. This report describes a 7‐year‐old Q uarter H orse gelding that initially presented following suspected trauma to the left eye but subsequently developed bacterial meningitis, and a nasal and palpebral abscess, all of which cultured the same isolate of E scherichia coli . The entry site of infection in bacterial meningitis is often related to a breach in the calvarium and extension of bacteria residing in the paranasal sinuses. This case is unique as there were multiple pathways through which bacteria may have entered the central nervous system including haematogenous spread from a nasal abscess, local extension of periocular infection or an undetected skull fracture. Aside from persistent blindness in the left eye, the horse made a full recovery.
The cervical spinal cords of 2 horses with equine degenerative myeloencephalopathy (EDM) were evaluated for evidence of oxidative damage to the central nervous system (CNS) using immunohistochemical staining for 3-nitrotyrosine (3-NT) and 4-hydroxynonenol (4-HNE). Neurons of the CNS from horses with EDM had positive immunohistochemical staining, whereas control samples did not, thus supporting the theory that oxidative damage is a potential underlying factor in horses with EDM. In addition, serum vitamin E concentration was low in both EDM-affected horses, and vitamin E concentration was also deficient in the cerebrospinal fluid in 1 EDM horse, further supporting the association between low vitamin E concentrations and oxidative damage to the CNS. Continued research is necessary to further define the pathophysiologic mechanisms of EDM.
OBJECTIVE To assess multiple central venous and arterial blood variables that alone or in conjunction with one another reflect global oxygenation status in healthy neonatal foals. ANIMALS 11 healthy neonatal foals. PROCEDURES Central venous and arterial blood samples were collected from healthy neonatal foals at 12, 24, 36, 48, 72, and 96 hours after birth. Variables measured from central venous and arterial blood samples included oxygen saturation of hemoglobin, partial pressure of oxygen, lactate concentration, partial pressure of carbon dioxide, and pH. Calculated variables included venous-to-arterial carbon dioxide gap, estimated oxygen extraction ratio, ratio of partial pressure of oxygen in arterial blood to the fraction of inspired oxygen, bicarbonate concentration, base excess, and blood oxygen content. RESULTS Significant differences between arterial and central venous blood obtained from neonatal foals were detected for several variables, particularly partial pressure of oxygen, oxygen saturation of hemoglobin, and oxygen content. In addition, the partial pressure of carbon dioxide in central venous blood samples was significantly higher than the value for corresponding arterial blood samples. Several temporal differences were detected for other variables. CONCLUSIONS AND CLINICAL RELEVANCE Results of this study provided information about several variables that reflect global oxygenation in healthy neonatal foals. Values for these variables in healthy foals can allow for comparison with values for critically ill foals in future studies. Comparison of these variables between healthy and ill foals may aid in treatment decisions and prognosis of clinical outcome for critically ill foals.
To determine the pharmacokinetics and clinical safety of acetaminophen after oral administration of 40 mg/kg q 12 hours or 60 mg/kg q 24 hours for 14 days.12 healthy light-breed neonatal foals.6 foals received acetaminophen at 40 mg/kg q 12 hours and 6 foals received 60 mg/kg q 24 hours for 14 days. The study dates were January 31 to April 15, 2023. Physical examinations were performed daily. Plasma disposition of acetaminophen was determined after the first, mid-point drug administration. Hematology and biochemistry analysis was performed before the study, day 7, and the last day of drug administration. Plasma acetaminophen concentrations were determined by high-performance liquid chromatography. Plasma pharmacokinetic parameters were estimated using noncompartmental analysis.No statistically significant changes occurred on hematology or biochemistry profiles. Elevations in γ-glutamyl transferase (GGT) and sorbitol dehydrogenase (SDH) were noted in 4 foals at various time points. The maximum plasma concentration (Cmax) occurred within 2 hours for both doses. The 60 mg/kg dose resulted in a larger median Cmax (range) at 28 μg/mL (22-32) than the 40 mg/kg dose at 23 μg/mL (19-27). The median area under the concentration-vs-time curve from 0 to 8 hours (AUC0-8 hour [range]) was 100 h•µg/mL (82-100) at 40 mg/kg and 128 h•µg/mL (120-168) for 60 mg/kg. Trough concentrations decreased over time for both regimens.Foals tolerate oral acetaminophen at 40 mg/kg q 12 hours or 60 mg/kg q 24 hours. Further analgesic and antipyretic studies will help to delineate optimal dosage regimens of acetaminophen to treat foals.
