Hematuria in a 3-month-old filly with an internal umbilical abscess and internal iliac artery aneurysm

A 3-month-old foal with a history of acute hematuria was evaluated. Hydronephrosis and hydroureter were visualized upon renal ultrasonography of the left kidney. Cystoscopy identified a blood clot occluding the left ureter. Computed tomography (CT) revealed a large retroperitoneal abscess at the level of the aortic bifurcation and a left internal iliac aneurysm. Due to the severity of the lesions and the poor prognosis, the filly was euthanized and the clinical findings were confirmed by post-mortem examination. This report emphasizes the value of obtaining a precise diagnosis via CT in order to avoid unviable treatment approaches when confronted with this unusual secondary complication of omphaloarteritis.Key clinical message:Umbilical complications are routinely diagnosed in equine neonatal medicine, and commonly lead to septicemia, physitis, and septic arthritis; severe internal umbilical abscessation, and subsequent vascular and urinary disorders are uncommon sequelae.     

Closing wedge ostectomy and medial distal tibia plate application for treatment of severe bilateral angular limb deformities in the hindlimbs of an 8-month-old foal

This case report describes the evaluation, surgical approach and outcome of an 8-month-old foal with severe angular limb deformities of both metatarsophalangeal joints (MTPJ). Radiography and computed tomography (CT) were used to diagnose a windswept deformity of the hindlimbs with associated bilateral physitis. The orthopaedic surgery was planned and rehearsed using three-dimensional (3D) bone models. A bilateral closing wedge ostectomy was performed on the distal MtIII, and 3.5 mm LCP^® medial distal tibia plates were used bilaterally for osteosynthesis. Even though convalescence was prolonged and complicated by partial unilateral implant failure and osteoarthritis (OA), reduction of the deformities was successful and resulted in a sound foal.     

Debridement of septic physeal lesions in 3 foals

Radiographically, osteolysis of the physis consistent with a septic physitis was observed in 3 foals. The foals were treated with surgical debridement and antimicrobials. Two of the horses were sound for use as adults; the third was euthanatized due to concurrent infectious arthritis and septicemia.     

Clinical Updates II: Topics of Interest Pertaining to the Distal Limb

Regional limb perfusion is used to treat infections of the distal limb and can be performed using a peripheral vein or the intraosseous route; the peripheral vein is the preferred technique. Other distal limb entities of clinical importance include foot conformation problems, bruising, heel pain, navicular disease, degenerative joint disease, tendonitis and desmitis. Specific clinical problems of the distal limb seen in the foal and aged horse are frequently managed with good foot care.     

Comparison of 2 techniques for regional antibiotic delivery to the equine forelimb: intraosseous perfusion vs. intravenous perfusion

The purpose of this study was to compare the synovial fluid concentrations and pharmacokinetics of amikacin in the equine limb distal to the carpus following intraosseous and intravenous regional perfusion. The front limbs of 6 horses were randomly assigned to either intraosseous or intravenous perfusion. A tourniquet was placed distal to each carpus and the limb perfused with 500 mg of amikacin. Systemic blood samples and synovial fluid samples were collected over 70 min from the distal interphalangeal (DIP) joint, metacarpophalangeal joint, and digital flexor sheath. The tourniquet was removed following the 30 min sample collection. The mean peak amikacin concentration for the DIP joint was significantly higher with intravenous perfusion. There were no significant differences in time to peak concentration or elimination half-life between methods at each synovial structure. Each technique produced mean peak concentrations ranging from 5 to 50 times that of recommended peak serum concentrations for therapeutic efficacy.     

Long bone failure after intraosseous regional perfusion

A 5-year-old Australian Stock Horse gelding was initially referred to the Charles Sturt University Veterinary Clinical Centre (CSUVCC) for assessment of a penetrating laceration over the medial splint bone (second metacarpal bone) of the left foreleg. Clinical examination failed to reveal a communication with a synovial structure, but radiographs showed a palisading bone reaction on the proximal aspect of the medial splint bone which was thought to be a characteristic of infection. Soft tissue swelling precluded access to a peripheral vein, so a decision was made to use intraosseous regional limb perfusion. This was achieved through an access portal in the lateral diaphysis of the third metacarpal bone (McIII). Subsequently, the horse developed lameness and further investigation revealed a nondisplaced longitudinal fracture of McIII propagating from the intraosseous regional perfusion access portal.     

Septic arthritis in foals

In the neonatal foal septic arthritis is an important cause of morbidity that may limit future athletic performance. This is often despite a good prognosis for resolution of joint infection. This article presents a review of the diagnosis and treatment of septic arthritis in foals less than 2 months of age, including an overview of our current understanding of inflammatory joint disease in the neonate. Management options are described, with emphasis on tailoring therapy to the individual foal based on accurate staging and monitoring of the disease process. Special considerations relevant to the immature animal are addressed.     

Preliminary Report: The Development of an Intraosseous Infusion Technique for Neonatal Foals

Six normal foals between the ages of 2 and 7 days were used in this study to develop a technique for intraosseous infusion in equine neonates. A 14-gauge 1/2-inch needle was placed intraosseously in the right proximal medial one-third aspect of the radius and tibia of each foal. A maximum of 1 L of isotonic fluids was administered intraosseously at these sites. Radiographs were taken at the time of intraosseous needle placement, and at days 10, 30, and 60 following the procedure. The mean time for needle placement was 33 seconds for the tibia and 63 seconds for the radius. The mean fluid flow rates for the tibia were 47 mL/min and for the radius 27 mL/min. Minimal technical difficulties were encountered with the intraosseous site in the tibia, but subperiosteal and/or subcutaneous fluid leakage and needle displacement or occlusion were commonly seen in the radius. The local soft tissue swellings and periosteal reactions seen following the procedure had resolved by 2 months. Intraosseous infusion offers a safe, practical, and effective alternative to vascular access for fluid administration in neonatal foals. (Journal of Veterinary Internal Medicine 1993; 7:377–382. Copyright © 1993 by the American College of Veterinary Internal Medicine.)     

A comparison of foal and adult horse neutrophil function using flow cytometric techniques

Flow cytometric assays were used to compare phagocytic and oxidative burst activity of neutrophils from healthy foals less than 7 days of age with the activity of cells from healthy adult horses. The phagocytosis of Staphylococcus aureus by foal neutrophils was less than that observed for adult neutrophils when autologous serum was used as the source of opsonins in the assay. The use of adult serum did not significantly improve the ability of foal neutrophils to attach bacteria. The oxidative burst activity of foal neutrophils was equivalent to that of adult cells. However, when serum or plasma was incorporated into the oxidative burst assay, foal neutrophils demonstrated greatly reduced autofluorescence and a suppressed response to phorbol myristate acetate (PMA), relative to that demonstrated by adult cells. These results suggest that peripheral blood neutrophils from foals have a reduced ability to phagocytose bacteria relative to that exhibited by adult horse neutrophils and that the oxidative burst activity of foal neutrophils is down-regulated in response to an unidentified serum factor(s). Such changes may contribute to the increased susceptibility of foals to septic disease.     

Fibrin deposits and organ failure in newborn foals with severe septicemia

Background: Septicemia in human neonates frequently is complicated by activation of the coagulation system, disseminated intravascular coagulation (DIC) and multiple organ failure syndrome, which may contribute to high mortality. In adult horses with DIC, the lung has been the organ most frequently affected by fibrin deposits. In addition, in vivo studies suggest that hemostatic mechanisms may be immature in foals <1‐day old. Hypothesis: Newborn foals with severe septicemia have fibrin deposits in their tissues independently of their age, and these fibrin deposits are associated with organ failure. Animals: Thirty‐two septic and 4 nonseptic newborn foals euthanized for poor prognosis. Methods: Tissue samples (kidney, lung, and liver) collected on postmortem examination were stained with phosphotungstic acid hematoxylin (PTAH) and immunohistochemistry (IHC) for blind histologic examination. A fibrin score (grades 0–4) was established for each tissue sample and for each foal. Medical records were reviewed for assessing clinical evidence of organ failure during hospitalization. Results: Fibrin deposits were found in most septic foals (28/32 when using IHC and 21/32 when using PTAH), independently of the age of the foal. The lung was the most affected tissue (97% of the septic foals). Additionally, organ failure was diagnosed in 18/32 septic foals (8 with respiratory failure, 14 with renal failure), although a statistical association with severe fibrin deposition was not identified. Conclusions and Clinical Importance: Nonsurviving septic foals have fibrin deposits in their tissues, a finding consistent with capillary microthrombosis and DIC.     

What is the likelihood that Thoroughbred foals treated for septic arthritis will race?

REASONS FOR PERFORMING STUDY: Septic arthritis is a serious problem in the neonate, with a poor prognosis being reported for recovery. The impact of neonatal septic arthritis on the likelihood that Thoroughbred (TB) foals will start on a racecourse is not known. HYPOTHESIS: The development of septic arthritis in a TB foal significantly reduces the likelihood that it will race when compared to foals from the same dam. METHODS: Medical records of 69 foals treated for septic arthritis were reviewed. The dam's foaling records were reviewed and lifetime racing records were then retrieved for both the affected foals and at least one of their siblings (controls). Outcomes that were statistically evaluated included discharge from the hospital and whether the foal eventually raced. Univariate analyses of categorical variables were conducted for each outcome. The number of affected and unaffected foals that raced at least once were compared using regression analysis. Survival analysis was used to compare age at first race between the study and comparison groups. RESULTS: Foals with septic arthritis were less likely to start on a racecourse compared to controls (odds ratio [OR] 0.28; 95% confidence interval [CI] 0.12-0.62, P = 0.001), while those foals that were discharged from the hospital were also less likely to start on a racecourse compared to controls (OR 036; CI 0.15-0.83, P = 0.008). The presence of multisystem disease was associated with a decreased likelihood of surviving to be discharged (OR 0.13; 95% CI 0.02-0.90; P = 0.005), but did not affect the likelihood that they would start in at least one race if discharged successfully (OR 0.45; 95% CI 0.04-2.81; P = 0.34) compared to the other foals with septic arthritis. Log-rank comparison of survival curves confirmed that foals discharged following treatment for septic arthritis took significantly longer to start in their first race compared to the sibling population (mean age of study group 1757 days, CI 1604-1909; mean age of sibling group 1273 days, CI 1197-1349; P = 0.0006). CONCLUSIONS: The development of septic arthritis in a TB foal significantly reduces the likelihood that it will start on a racecourse when compared to controls. POTENTIAL RELEVANCE: Accurate figures allowing a realistic assessment of the athletic future of a foal following treatment for septic arthritis are of significance for both owner and treating veterinarian.     

Bilateral renal dysplasia,hydronephrosis, and hydroureter in a septic neonatal foal

A Canadian warmblood foal treated for septic polyarthritis was diagnosed with bilateral congenital renal dysplasia, hydronephrosis, and hydroureter at 2 weeks of age based on abdominal ultrasound and postmortem examination. Intermittent abdominal pain throughout the course of treatment was attributed to hydronephrosis and hydroureter.     

Osteomyelitis and Osteonecrosis after Intraosseous Perfusion with Gentamicin

Objective: To describe and discuss previously unreported complications associated with intraosseous perfusion with gentamicin in horses. Study Design: Case report. Animals: Ten‐year‐old Warmblood gelding. Methods: Intraosseous perfusion with gentamicin into the proximal phalanx (P1) was used as part of the treatment regimen for distal interphalangeal joint and navicular bursa synovial sepsis. Although the sepsis responded favorably complications developed at the perfusion site, including persistent osteomyelitis, progressive osteonecrosis, and ultimately pathologic fracture of P1. Results: The progression of the clinical signs and findings at necropsy are suggestive of a toxic osteonecrosis secondary to intraosseous perfusion. Conclusions: Further work is needed to investigate the effects of high dose gentamicin on equine mesenchymal cells that may be achieved during intraosseous perfusion. Clinical Relevance: Lower doses of perfusate within the medullary canal of P1 or alternative perfusion sites should be considered.     

Plasma adrenocorticotropin, cortisol, and adrenocorticotropin/cortisol ratios in septic and normal-term foals

BACKGROUND: Little information exists on the hypothalamic-pituitary-adrenal axis in septic foals. HYPOTHESIS: The plasma concentrations of adrenocorticotropin (ACTH) and cortisol are expected to be higher in septic foals as compared to normal foals. The concentrations of hormones in septic foals also are expected to differ further depending upon survival. ANIMALS: Twenty-eight control foals and 46 septic foals <14 days of age were included in this study. METHODS: Blood was collected in EDTA once from 28 normal foals born in the University of Georgia or Cornell University equine research herds and from 46 septic foals within 12 hours after admission to 1 of the 3 tertiary care referral centers involved in the study. Septic foal selection was based on a sepsis score of >11 or a positive blood culture. The control foals were age matched to the septic foals in the study. ACTH and cortisol concentrations were measured by a chemiluminescent immunoassay system. RESULTS: Cortisol concentrations in control foals did not vary with age. Septic foals had significantly higher mean ACTH, cortisol, and ACTH/cortisol ratios than did normal foals. Within the septic foal group, 28 foals survived to discharge, and 18 were euthanized or died. The mean age was not significantly different between the septic surviving and nonsurviving foals. The mean ACTH/cortisol ratio was significantly higher in the septic nonsurviving foals as compared to the septic surviving foals. CONCLUSIONS AND CLINICAL IMPORTANCE: Septic foals had higher hormone concentrations as compared to normal foals, which is an expected endocrine response to critical illness. The increased ACTH/cortisol ratio in nonsurviving septic foals in comparison to surviving septic foals could indicate hypothalamic-pituitary-adrenal axis dysfunction at the level of the adrenal gland in critically ill septic foals.     

Antithrombin: Could It be a Diagnostic and Prognostic Marker in Septic Neonatal Foals?

Antithrombin (AT) levels are lower in human neonates affected by sepsis and in nonsurvivors compared with survivors. The aims of this study were to evaluate AT profile in healthy newborn foals and its diagnostic and prognostic role in septic foals during the first week of life. Fifteen healthy foals and 35 septic foals were enrolled. Blood samples were collected from each healthy foal at 30 minutes, 3 and 12 hours from birth, daily from days 1–7, and at days 10 and 14. Blood was collected from each septic foal twice a day from admission to discharge or death. The AT analysis was performed by chromogenic method. Healthy foals showed decreasing levels of AT between 3 hours and 2 days, followed by an increasing trend. Septic foals did not show any difference during the period of observation, and no differences were found between healthy and septic age-matched foals. The analysis of AT activity on the day of admission in septic foals showed higher levels compared with healthy foals, in animals hospitalized at 12 and 24 hours of age (P < .01). No differences were found at admission between foals affected by sepsis and that with septic shock. Nonsurviving foals showed significantly lower levels at 3 and 4 days of age compared with surviving foals; when surviving and nonsurviving foals were compared independently by the age, nonsurviving foals showed significant (P < .05) lower levels 12 hours after admission. In conclusion, AT seems to show neither a diagnostic nor a prognostic role in septic neonatal foals.     

Biochemical markers of cardiac injury in normal, surviving septic, or nonsurviving septic neonatal foals

The cardiac biomarkers cardiac troponin T (cTnT) and I (cTnI) and the cardiac isoenzyme of creatine kinase (CKMB) are used extensively in human medicine to diagnose and provide valuable prognostic information in patients with ischemic, traumatic, and septic myocardial injury. We designed a study to establish normal values for these markers in healthy, neonatal foals and to compare them with values obtained from septic neonates in a referral hospital population. The 25th, 50th, 75th, and 95th percentiles for cTnI and CKMB in the healthy-foal population were 0.08, 0.14, 0.25, 0.49 ng/mL and 1.4, 2.3, 4.0, 7.4 ng/mL, respectively. The values obtained for cTnT were frequently (43/52 foals; 83%) below the lower limit of detection of the assay (0.009 ng/mL), but the median and range were 0.009 and 0.009-0.041 ng/mL, respectively. In the septic foal population, the 25th, 50th, 75th, and 95th percentile values for cTnI and CKMB were 0.05, 0.12, 0.22, and 1.10 ng/mL and 2.0, 4.4, 7.8, and 24 ng/mL, respectively. The values obtained for cTnT were less frequently below the lower limit of detection (23/38 foals; 60%) compared with the healthy foal population, and the median and range were 0.009 and 0.009-0.20 ng/mL, respectively. Significantly higher values were observed for cTnT and CKMB in septic foals compared with the healthy neonatal foal population, but there were no differences among septic foals in survivors compared with nonsurvivors. These findings suggest that myocardial injury occurs during septicemia in neonatal foals but that the injury is not associated with survival among septic foals.     

Septic arthritis of the first and second cervical vertebral articulations with vertebral osteomyelitis in a foal caused by Salmonella

A case of infectious arthritis of a cervical vertebral articulation and vertebral osteomyelitis in a foal caused by Salmonella is described. Ultrasound images of the cervical facet joints were suggestive of septic arthritis and ultrasound facilitated needle placement for arthrocentesis and joint lavage. Due to the uncommon location of the infection, diagnosis of septic arthritis was not immediate and, despite aggressive intra‐articular lavage and instillation of appropriate intra‐articular antibiotics after hospitalisation, we were unable to resolve the infection in this foal. Radiographs did not show evidence of osseous involvement until later in the course of the infection. Septic arthritis should be suspected in cases with similar clinical and laboratory findings and radiographic changes may not be present early in the course of infection. Ultrasound imaging provided the most useful diagnostic information regarding infection of the cervical joints, facilitating both diagnosis and treatment.     

Evaluation of safety and pharmacokinetics of vancomycin after intraosseous regional limb perfusion and comparison of results with those obtained after intravenous regional limb perfusion in horses

OBJECTIVE: To evaluate the clinical effects and pharmacokinetics of vancomycin in plasma and synovial fluid after intraosseous regional limb perfusion (IORLP) in horses and to compare results with those obtained after IV regional limb perfusion (IVRLP). ANIMALS: 6 horses. PROCEDURES: 1 forelimb of each horse received vancomycin hydrochloride (300 mg in 60 mL of saline [0.9% NaCl] solution) via IORLP; the contralateral limb received 60 mL of saline solution (control). Solutions were injected into the medullary cavity of the distal portion of the third metacarpal bone. Synovial fluid from the metacarpophalangeal (MTCP) and distal interphalangeal (DIP) joints and blood were collected prior to perfusion and 15, 30, 45, 65, and 90 minutes after beginning IORLP, and synovial fluid from the MTCP joint only and blood were collected 4, 8, 12, and 24 hours after beginning IORLP. Plasma urea and creatinine concentrations and clinical appearance of the MTCP joint region and infusion sites were determined daily for 7 days. Results were compared with those of a separate IVRLP study. RESULTS: Clinical complications were not observed after IORLP. Mean vancomycin concentration in the MTCP joint was 4 microg/mL for 24 hours after IORLP. Compared with IORLP, higher vancomycin concentrations were detected in the DIP joint after IVRLP. Compared with IVRLP, higher vancomycin concentrations were detected in the MTCP joint for a longer duration after IORLP. CONCLUSIONS AND CLINICAL RELEVANCE: IORLP with 300 mg of vancomycin in a 0.5% solution was safe and may be clinically useful in horses. Intravenous and intraosseous routes may be better indicated for infectious processes in the DIP and MTCP joints, respectively.     

Haematogenous septic arthritis,physitis and osteomyelitis in foals: A tutorial review on pathogenesis,diagnosis, treatment and prognosis. Part 1

Haematogenous septic arthritis, physitis and osteomyelitis (SAPO) is a potentially debilitating or even life-threatening disease entity encountered in foals of all ages between birth and approximately 7 months old. Correct, and complete, diagnosis and successful treatment require collaboration between specialties including medicine, anaesthesia, diagnostic imaging, surgery and rehabilitation services. However, in order to succeed, it is important that all specialties have an overall knowledge of all aspects of the disease complex. Therefore, the aim of this review is to give an overview of aetiology, presenting complaints, clinical findings, diagnostic imaging, treatment, rehabilitation and prognosis. Part one deals with all aspects of aetiology and how to make a diagnosis. Part two deals with all aspects of treatment, rehabilitation and prognosis.     

Fibrinous pericarditis and cardiac tamponade in a 3‐week‐old pony foal

A 3‐week‐old Pony of the Americas foal presented with a history of respiratory distress presumed to result from Actinobacillus equuli pleuropneumonia and septic arthritis. Failure of transfer of passive colostral immunity was suspected, but not confirmed, based on a history of the foal being separated from its dam shortly after parturition. Transient improvement was noted following thoracocentesis and removal of approximately 600 ml of pleural fluid but progressive clinical signs of congestive heart failure developed. Fibrinous pericarditis with evidence of cardiac tamponade was subsequently diagnosed via thoracic ultrasonography. Early clinical signs of cardiogenic shock were identified and fibrinopurulent exudate removed through a catheter placed with ultrasound guidance into the pericardium. The foal experienced cardiorespiratory arrest during the procedure and died despite resuscitative efforts. Post mortem examination identified extensive hypertrophy of the pericardium, septic arthritis, mild pleural effusion and focal bronchopneumonia. This report details the clinical evaluation, haematology, treatment and post mortem pathology of a foal with Actinobacillus equuli associated fibrinous pericarditis, as well as a brief review of cardiac tamponade.