Concentrations of serum amyloid A and lipopolysaccharide-binding protein in horses with colic

OBJECTIVE: To determine concentrations of 2 acute-phase proteins (serum amyloid A [SAA] and lipopolysaccharide-binding protein [LBP]) in serum samples obtained from horses with colic and identify relationships among these acute-phase proteins and clinical data. ANIMALS: 765 horses with naturally developing gastrointestinal tract diseases characterized by colic (ie, clinical signs indicative of abdominal pain) and 79 healthy control horses; all horses were examined at 2 university teaching hospitals. PROCEDURE: Serum concentrations of SAA and LBP were determined by immunoturbidometric and dot-blot assays, respectively. RESULTS: SAA and LBP concentrations were determined for 718 and 765 horses with colic, respectively. Concentrations of SAA were significantly higher in nonsurvivors than in survivors, and horses with enteritis or colitis and conditions characterized by chronic inflammation (eg, abdominal abscesses, peritonitis, or rectal tears) had SAA concentrations significantly greater than those for horses with other conditions. Serum concentrations of LBP did not correlate with outcome, disease process, or portion of the gastrointestinal tract affected. CONCLUSIONS AND CLINICAL RELEVANCE: Circulating concentrations of SAA were significantly higher at admission in horses with colic attributable to conditions having a primary inflammatory cause (eg, enteritis, colitis, peritonitis, or abdominal abscesses) and were higher in horses that failed to survive the episode of colic, compared with concentrations in horses that survived. Serum concentrations of LBP did not correlate with survival. Analysis of these findings suggests that evaluation of SAA concentrations may be of use in identifying horses with colic attributable to diseases that have inflammation as a primary component of pathogenesis.     

Differentiation between intra-abdominal neoplasms and abscesses in horses, using clinical and laboratory data: 40 cases (1973-1988)

The medical records of 25 horses with intra-abdominal neoplasms and 15 horses with intra-abdominal abscesses were reviewed. Common clinical signs of disease observed by owners of horses in both groups included anorexia, weight loss, fever, signs of colic, and depression. Clinical laboratory abnormalities included leukocytosis, hyperfibrinogenemia, hypoalbuminemia, and hypocalcemia. There was considerable overlap of laboratory test results within and between the 2 groups of horses. Peritoneal fluid was classified as an exudate in 12 of 15 horses with intra-abdominal abscesses and in 14 of 25 horses with intra-abdominal neoplasms. Cytologic examination of peritoneal fluid yielded an accurate diagnosis in 11 of 25 horses with neoplasia and in 3 of 15 horses with abscesses. A mean number of 1.45 cytologic analyses/horse was needed to diagnose neoplasms in the 11 horses in which the analysis was successful in definitively diagnosing the condition.     

Perisuspensory abscessation in eight horses with hindlimb cellulitis

This study reports a distinct presentation of cellulitis, which involved formation of perisuspensory abscessation in eight horses. Medical records of horses presented for cellulitis unresponsive to medical treatment were reviewed. Cases in which perisuspensory abscesses were diagnosed were included. All abscesses formed between the cannon bone and suspensory ligament and extended around one or both suspensory branches. Abscesses were diagnosed via ultrasonography upon admission in three horses and developed within a few days following admission in five horses. All horses were treated with broad-spectrum antibiotics, anti-inflammatories, topical therapies and regional limb perfusions; however, only partial improvement of clinical signs was observed with medical therapy alone. Full resolution of clinical signs was obtained in all cases once the abscess was surgically lanced and drained. The surgical drainage was performed standing in seven cases and under general anaesthesia in one. In all cases, Staphylococcus aureus was cultured. Six out of eight isolates showed at least some level of antibiotic resistance, and penicillin and trimethoprim sulfonamides were most commonly involved. Short-term complications included skin necrosis in two cases and mild impaction colic in two cases and were successfully treated. All horses were discharged from the hospital within 4–13 days and were sound upon discharge. All Thoroughbreds (n = 7) were able to return to their intended use, and the Standardbred was unraced prior to the cellulitis event and remained unraced afterwards.     

Effects of oral powder electrolyte administration on packed cell volume,plasma chemistry parameters,and incidence of colic in horses participating in a 6-day 162-km trail ride

This study evaluated the effects of administering oral powder electrolytes on packed cell volume (PCV), plasma chemistry parameters, and incidence of colic in horses participating on a 6-day 162-km trail ride in which water was not offered ad libitum. Twenty-three horses received grain with powder electrolytes daily while 19 control horses received grain only. Horses were ridden approximately 32 km a day at a walk or trot. Packed cell volume and plasma chemistry parameters were analyzed daily. Episodes of colic were diagnosed and treated by a veterinarian unaware of treatment group allocation. Blood parameters and incidence of colic were compared between treatment groups. Electrolyte administration did not alter PCV or plasma chemistry parameters compared to controls. The incidence of colic was significantly higher in treated horses (P = 0.05). Oral powder electrolytes did not enhance hydration status or electrolyte homeostasis and may be associated with colic in horses participating on long distance trail rides similar to this model.     

Inflammatory bowel disease in horses: 11 cases (1988-1998).

OBJECTIVE: To determine clinical and surgical abnormalities in, and long-term outcome of, horses that undergo surgery because of colic secondary to inflammatory bowel disease (IBD). DESIGN: Retrospective study. ANIMALS: 11 horses. PROCEDURE: Medical records of horses that had undergone abdominal surgery and in which IBD had been diagnosed on the basis of histologic examination of intestinal biopsy specimens were reviewed. RESULTS: 5 horses were examined because of acute colic and 6 were examined because of chronic colic. At surgery, all 11 horses had edematous or hemorrhagic bowel segments suggestive of IBD. In addition, 6 horses had circumferential mural bands (CMB) causing constriction of the small (4 horses) or large (2) intestine. Intestinal resections were performed in 7 horses. All 11 horses survived surgery and were discharged from the hospital; 10 horses were still alive at the time of follow-up (1.5 to 7 years after surgery). CLINICAL IMPLICATIONS: Results suggest that IBD is an uncommon cause of colic in horses. Surgical resection of segments of intestine with constrictive CMB may relieve clinical signs of colic. Horses with IBD that had surgery had a good prognosis for long-term survival.     

Occurrence of Anoplocephala perfoliata infection in horses in Ontario, Canada and associations with colic and management practices

Infection with the tapeworm Anoplocephala perfoliata has been found to be associated with equine colic in horses in the United Kingdom. Using a matched case-control study design, data collected from 117 pairs of horses in Ontario were examined for evidence of associations between risk of colic and A. perfoliata infection, and between seropositivity to infection and management practices. Cases were horses in southern Ontario diagnosed with colic by local veterinarians, and control horses were from the same stables as cases and were matched by age, breed and gender where possible. Infection status was defined on the basis of positive results upon coprological examination, and/or seropositivity to a 12/13 kDa A. perfoliata secretory protein. Fifty-six percent of the 234 horses were seropositive for A. perfoliata, but eggs were found in samples from only 6% of horses. Horses dependent on pasture for a large part of their diet were significantly more likely to have ELISA optical density levels above 0.600 compared to other horses (odds ratio [OR]=6.38; p=0.029). This finding identified exposure to pasture as an important source of A. perfoliata infection in the horses used in the study. In a subset of 46 pairs of horses for which control horses had no known history of colic, a statistically significant negative association was found between the risk of colic and optical density (OD) levels >0.200-0.600, relative to OD levels < or = 0.090 (OR=0.08; p=0.017). There was no other statistical evidence of an association between the risk of colic and A. perfoliata infection.     

Internal abdominal abscesses in the horse: a study of 25 cases

internal abdominal abscesses in 25 horses, including 8 horses that died or were euthanatized, were found to be caused by Streptococcus equi, Streptococcus zooepidemicus, or Corynebacterium pseudotuberculosis. Breed or sex predilection was not found. Although horses of all ages were affected, those under 5 years of age were more commonly affected. Nearly all of the horses had a history of respiratory catarrh or lymphadenitis. Horses with internal abdominal abscesses also had intermittent, prolonged colic or chronic weight loss. Most horses had increased rectal temperature, increased heart and respiratory rates, and varying degrees of anorexia. Chronic depression anemia, increased plasma fibrinogen concentration, increased total plasma protein with hypergammaglobulinemia, and hypoalbuminemia were prominent clinicopathologic findings. Results of rectal examination or surgical exploration often revealed an abdominal mass. Peritoneal fluid from 14 horses was examined, and the protein content was greater than 2.5 g/dl, with increased numbers of neutrophils. Culture results were negative in all 14 cases, although bacteria were seen intracellularly in 5 cases. Long-term (2- to 6-month) antimicrobial therapy with procaine penicillin G resulted in clinical resolution in most of these animals.     

Caecal intussusceptions in horses: a New Zealand perspective

Objective To establish the prevalence of intussusceptions involving the caecum in a population of horses admitted to a university hospital for colic. Design Retrospective clinical study Methods Medical records of all horses admitted to the Massey University Veterinary Teaching Hospital between 1991 and 2004 were examined for information of those horses diagnosed with an intussusception involving the caecum. Results A total of 135 horses were admitted for colic surgery during the study period and 61 horses had a diagnosis of ileocaecal (37), caecocaecal (5) or caecocolic intussusception (19) made either at surgery or necropsy. Of the horses with ileocaecal intussusception, 32 had an incomplete hand-sewn ileocaecostomy without reduction and 29 survived to discharge. All the horses with caecocaecal intussusceptions were diagnosed preoperatively via rectal examination and/or transabdominal ultrasound: 2 were euthanased at surgery and 3 survived to discharge. In the 19 horses with caecocolic intussusceptions, manually reduction at surgery was performed in 6 and 5 of them survived to discharge. A typhlectomy was performed via a colotomy in 6 horses, 3 of which survived to discharge. Conclusions The high prevalence of intussusceptions involving the caecum seen at this referral centre may indicate a higher prevalence in New Zealand than is reported elsewhere in the world. Clinical relevance Intussusceptions involving the caecum should be considered as a differential diagnosis in horses presenting with chronic low-grade colic. Transabdominal ultrasound is useful for identifying caecocaecal and caecocolic intussusceptions. Hand-sewn side-to-side incomplete ileocaecostomy is a quick, effective and safe method of surgical treatment of ileocaecal intussusceptions.     

Idiopathic perforating ulceration of the small intestine in five adult horses

Perforating ulceration of the small intestine was diagnosed in 5 adult horses. Affected horses presented with signs of low‐grade colic, depression and inappetance. Abdominal paracentesis yielded abnormal peritoneal fluid in all cases. Perforating ulcers were located at the mesenteric border in 4 horses and the ileum in one horse. All horses had diffuse septic peritonitis. The aetiology of the condition is unknown.     

Are feeding practices associated with duodenitis-proximal jejunitis?

REASONS FOR PERFORMING STUDY: Feeding concentrate has been putatively associated with risk of development of duodenitis-proximal jejunitis (DPJ); however, this association has not been evaluated systematically in a controlled study. OBJECTIVES: To determine whether there was evidence that feeding practices were associated with increased odds of developing DPJ employing a case control study. HYPOTHESIS: The amount of concentrate fed daily to horses is significantly greater among horses that develop DPJ than control horses with either lameness or other types of colic. METHODS: Feeding practices of cases of DPJ diagnosed between 1997 and 2003 were compared with those of 2 populations of control horses (colic controls and lameness controls) admitted to the clinic from the same time period. Following multiple imputation of missing data, comparisons were made using polytomous logistic regression. RESULTS: Horses with DPJ were fed significantly more concentrate and were significantly more likely to have grazed pasture than either control populations; DPJ horses were significantly more likely to be female than were lameness horses. Results were unchanged after adjusting for bodyweight of the horse. CONCLUSIONS: Feeding and grazing practices differ among horses with DPJ relative to horses with other forms of colic and lame horses. POTENTIAL RELEVANCE: The observed magnitudes of association were not sufficiently strong to merit diagnostic/predictive application; however, these observations, if substantiated by other studies, might provide important aetiological clues.     

Equine Colic: Seventy-six Cases Resulting from Incarceration of the Large Colon by the Suspensory Ligament of the Spleen

Incarceration of the large colon by the suspensory ligament of the spleen was diagnosed and surgically corrected on exploratory celiotomy in 76 horses exhibiting abdominal pain. The condition was diagnosed most frequently during the winter months in mature males of mean age 4.7 years. Clinical signs progressed slowly and included mild to moderate abdominal pain and distension with moderate tachycardia. The mean duration of colic prior to surgical intervention was 20.7 hours. The mild nature of the colic, the findings on palpation per rectum, and the continued passage of feces in 40% of horses, frequently led to the diagnosis and treatment of colonic impaction prior to admission. The condition was correctly diagnosed prior to exploratory celiotomy, by palpation per rectum, in only 18% of cases. Two types of displacement were identified. Sixty-six (86.8%) animals survived and were discharged from the hospital; the longterm survival rate was 78.9%.     

Prognosis in equine medical and surgical colic

A retrospective study was performed on 649 horses admitted to the Clinic of Equine Internal Medicine (Utrecht University) for gastrointestinal colic. The aim of this study was to provide a better guideline for determining prognosis in horses with colic. Short- and long-term survival were evaluated, and Cox regression analysis was performed to identify the clinical and clinicopathologic variables usable to predict survival. Intestinal displacements and strangulations were the most frequently diagnosed causes of colic. Regarding the surgically treated horses, 54% were discharged and 88% of these were still alive after 1 year. In comparison, 85% of medically treated patients were discharged and 93% were still alive after 1 year. Only 4.4% of all long-term survivors did not return to the expected level of performance, and 32% suffered from recurrent colic. Duration of colic signs, heart rate, intestinal motility, skin tenting, level of pain, and gross appearance of peritoneal fluid were shown to be significantly associated with survival. White blood cell count, packed cell volume, blood pH, and color of the mucous membranes did not show any prognostic significance. Thus, clinical variables appeared to be the most relevant predictors of the outcome of gastrointestinal colic.     

Accuracy of increased large-intestine wall thickness during ultrasonography for diagnosing large-colon torsion in 42 horses

Large-colon torsion is a common cause of colic in horses and has a worse prognosis and higher cost than other causes of surgical colic of the large colon. During large-colon torsion, the colon wall becomes thick due to vascular occlusion. Therefore, we hypothesized that detecting increased colon wall thickness during ultrasonography would be an accurate preoperative test for large-colon torsion. The sample population consisted of 42 horses that were admitted for surgical treatment of colic localized to the large colon. The diagnosis was confirmed at surgery or necropsy examination. Twelve (29%) of these horses were diagnosed with large-colon torsion. Duplicate ultrasonographic measurements of colon wall thickness were made at six abdominal locations and an average measurement was calculated. For four of these six sites, a significant difference (P < 0.005) was detected between horses with and without large-colon torsion. All four tests were moderately sensitive and highly specific for diagnosing large-colon torsion using five decision criteria. Using a ventral abdominal window, a colon wall thickness > or = 9 mm accurately predicted large-colon torsion in eight of the 12 horses (sensitivity, 67%; confidence interval [CI], 36-98%) and correctly predicted that large-colon torsion was absent in 28/28 horses (specificity 100%; CI, 98-100%). Intraobserver repeatability was assessed by evaluating the difference between the first and second measurements obtained, which was < or = 2 mm. Therefore, detecting increased large-colon wall thickness during ultrasonography is a reproducible and accurate preoperative test for large-colon torsion in horses with surgical colic localized to the large colon.     

Non-strangulating intestinal infarction in horses in the UK: A review of 15 cases

The clinicopathological features of 15 horses diagnosed with non-strangulating intestinal infarction (NSII) based on identification of focal areas of intestinal necrosis without mesenteric strangulation were reviewed. The mean age at presentation was 16.3 years, median 13 years, and there was no age, sex, or breed predilection. The major presenting clinical signs included: acute colic ≤ 24 h duration in nine horses; diarrhoea, depression, and inappetence in four horses; and low-grade chronic or recurrent colic, depression, and inappetence in two horses. One horse presented with both acute colic and diarrhoea. Predisposing diseases included colitis or typhlocolitis in five horses and an initial strangulating small intestinal obstruction in three horses, but in seven horses no underlying or predisposing disease was identified. Four cases were managed medically and 11/15 were managed surgically. The most useful diagnostic test was exploratory celiotomy and the only successful treatment was complete resection of the necrotic intestine. Prognosis for survival was poor with a survival rate of only 1/15 (7%). Among the 15 horses, both single and multiple NSII lesions were seen, and they occurred in both the small intestine and large intestines. There was no evidence of Strongylus vulgaris infestation in any of the affected horses.     

Black walnut toxicosis in ten horses

Black walnut toxicosis was diagnosed in 10 horses at one stable. The time from exposure to shavings to development of clinical signs was 8 to 12 hours. Most common clinical signs were moderate to severe laminitis (Obel grade 2 or 3), pitting edema of the distal portion of the limbs, and rapid respiratory rate. Two horses had clinical signs of colic and 2 other horses had anorexia and lethargy. All 10 horses recovered without complications.     

Hepatic abscesses in three horses

Hepatic abscesses were diagnosed in 3 adult horses. Two were < 4 years old and had evidence of concurrent immune-mediated conditions, including aseptic arthritis, immune-mediated thrombocytopenia, and immune-mediated anemia. Predisposing factors for hepatic abscess formation in these horses included prior abdominal surgery, proximal duodenitis/jejunitis, inflammatory bowel disease, and a penetrating foreign body in the large colon. Serum hepatic enzyme activities were within or slightly greater then reference limits in all 3 horses. The most pronounced and consistent abnormalities on CBC and serum biochemical analyses were hyperproteinemia, hyperglobulinemia, and a decreased albumin-to-globulin concentration ratio. Hepatic ultrasonography identified hepatic abscesses in all 3 horses. A variety of bacteria were isolated from these abscesses, including Staphylococus aureus and Bacteroides fragilis. One horse developed septic tibiotarsal arthritis, presumably as a result of intermittent bacteremia. Despite aggressive medical treatment, all horses were euthanatized because of a worsening condition and poor prognosis.     

Are horses that undergo an exploratory laparotomy for correction of a right dorsal displacement of the large colon predisposed to post operative colic,compared to other forms of large colon displacement?

Reason for performing study: It is a clinical impression that horses diagnosed with a right dorsal displacement (RDD) of the large colon, are more likely to suffer from recurrent episodes of colic post operatively, compared to other forms of nonstrangulating large colon displacement. Objectives: To investigate whether the type of nonstrangulating large colon displacement identified at exploratory laparotomy would influence long‐term outcome. Hypothesis: Horses identified with a RDD of the large colon at exploratory laparotomy would be more likely to experience recurrent episodes of post operative colic than other types of displacement. Materials and methods: Medical records for horses undergoing an exploratory laparotomy, from 2000–2008, for a nonstrangulating large colon displacement were reviewed. Data retrieved included: subject details, previous medical history, details of current episodes of colic, results of preoperative examination, surgical findings and procedures, post operative management and complications. Follow‐up information was obtained by reference to computerised clinical records and by telephone questionnaire administered to the horse's owner or carer, and included details of any colic episodes exhibited by the horse after discharge and whether a repeat celiotomy had been required to resolve the colic episodes. Results: There were 165 surgeries identified, in 154 horses. It was found that those horses with RDD were significantly more likely to experience recurrent episodes of colic requiring veterinary intervention post operatively compared to other types of displacement. Clinical relevance: Long‐term prognosis and likelihood of post operative complications is an important consideration for both owners and veterinarians.     

Determination of the acid-base status in 50 horses admitted with colic between December 1998 and May 1999

The purpose of the present study was to investigate the acid-base status and the concentration of organic acids in horses with colic caused by various disorders. Blood samples were collected from 50 horses with colic and from 20 controls. No intravenous fluids had been given prior to sample collection. Identified causes of colic included gastric ulceration, small intestinal volvulus, cecal intussusception, cecal rupture, colonic impaction, left dorsal colon displacement, right dorsal colon displacement, colonic volvulus, colitis, peritonitis, and uterine torsion. Thirty-seven horses recovered from treatment of colic, 8 horses were euthanized, and 5 died. Most cases were not in severe metabolic acidosis. In previous studies, most horses presented for diagnosis and treatment of colic were in metabolic acidosis and in shock.     

Cecocolic intussusception in horses: 11 cases (1979-1989)

Over a 10-year period, cecocolic intussusception was diagnosed in 11 of 842 horses undergoing surgical treatment for colic at the New York State College of Veterinary Medicine. Eight horses died or were euthanatized because of poor prognosis determined at surgery or because of postoperative complications. Three horses recovered without complication after manual reduction of the intussusception and partial typhlectomy, using an intestinal stapling device.     

A cross-sectional study of colic in horses on thoroughbred training premises in the British Isles in 1997

The aim of this study was to estimate the incidence of colic in horses in Thoroughbred training premises in 1997 in the British Isles. The seasonal pattern and outcome of colic episodes were also investigated, together with any association between premises level variables and colic. Data were collected by a postal questionnaire. The results showed a colic incidence density of 7.19/100 horse years (s.e. 0.42) and a cumulative incidence of colic of 5.80% (s.e. 0.30). Premises were grouped according to whether they had more Flat than National Hunt horses (Flat premises) or more National Hunt than Flat horses (NH premises). A similar rate of colic episodes was found in each group. However, significantly higher cumulative incidences of one episode of colic were found in the Flat premises and of multiple episodes in the NH premises, respectively. The outcome of each episode of colic showed spontaneous recovery in 28.7%, medical recovery in 63.1%, surgical recovery in 2.0% and death in 6.2% of cases. This indicated an overall mortality rate from colic of 0.45 deaths/100 horse years. The seasonal pattern of episodes of colic showed a spring and autumn peak, with significant differences in the seasonal pattern between the Flat and NH premises. Relative risk analysis and logistic regression modelling with random effects showed significant associations between the number of episodes of colic and the number of horses on the premises (allowing for the number of horses on each premises, the larger premises had a decreased risk of colic). After adjusting for the number of horses, 3 other variables were associated with colic; Flat premises (with an increased risk), the owner being the sole person looking after the horses (a decreased risk) and the premises being a combined training and breeding establishment (a decreased risk).