Gastric Ulceration causing poor performance in a horse!!

A 12 year-old event horse presented for poor performance that was best described as unwilling to "go forward". The gelding was evaluated for lameness and was described as sound. The gelding maintained a good appetite and there were no signs of colic behavior reported. A gastroscopy was scheduled and the owner was instructed to fast the horse for 18 hours. When the gastroscope was passed into the stomach a large volume of fluid was present mixed with feed material. Approximately 3 liters of fluid was removed from the stomach in order to visualize the non-glandular compartment. The remaining fluid was filled with feed material and was not removed. However, a clear pattern of non-glandular ulceration was noted throughout the exposed stomach wall (Figures 1-3).

 

 

Figure 1

 These ulcers appear full thickness thru the layer coating the inside of the stomach and are evenly spread through out the stomach. We were not able to visualize the glandular stomach or the pyloric region which may be abnormal in this horse. The fact that the gelding's stomach was filled with fluid and some feed after 18 hrs of fasting would suggest a delay in gastric emptying which may be associated with inflammation of the pyloric region. As such, this gelding will be treated with omeprazole for the appropriate period of time. In addition, the horse will be treated with a stomach coating medicine for the first 48 hrs to alleviate any immediate discomfort due to the ulcerations.

Figure 2

 This case presents yet another example of the types of clinical signs that may be associated with gastric ulcers. Classically we consider horses that have sings of colic, weight loss, poor appetite or failure to thrive. However, in my expereince, horses with gastric ulcers may present in many ways and this condition should be considered on our lists of differentials!!

Figure 3

Sand Impaction in a Horse

A six year old gelding presented for recurrent low grade fever and intermittent diarrhea. At the time of the initial exam the gelding was alert and showing no signs of discomfort. Vitals were normal and body temperature was 100.5 degrees.  A blood sample was collected for complete blood count (CBC) analysis and a rectal exam was performed. A large, firm structure was palpated along the left flank of the horse which was consistent with an impaction of the "pelvic flexure".  The fecal material removed from the rectum was partially formed and had a grainy feel to it. Several hand fulls of manure were placed in a rectal sleeve and the sleeve was filled with water (Figure 1).  A significant amount of sand was identified in the sleeve filled with water!

Figure 1

 The gelding was treated aggressively with water and mineral oil via a naso-gastric tube however; his condition worsened and he was referred to a surgical facility. Despite knowing that the gelding had a pelvic flexure impaction which is usually managed medically, the gelding was taken to surgery due to refractory pain. Abdominal exploration revealed an extremely large, firm impaction of the left colon which "bottle necked" at the pelvic flexure (blue arrow in Figure 2).  Discovery of such an impaction during surgery typically results in making a small opening in the colon wall and resolving the impaction. However, a small tear was discovered along the edge of the impaction which had resulted in fecal contamination of the abdomen. Prognosis was poor and the owners opted for humane euthanasia.

Figure 2

This case of sand impaction in a horse is sadly NOT uncommon in the state of Florida! The accumulation of sand within the colon of a horse is typically a result of poor pasture conditions and can develop very quickly. There are several "hair-pin" turns within the large colon of horses which create ideal conditions for the accumulation of sand and other debris. The pelvic flexure is one of those "hair-pin" turns and is one of the most common locations for colon impactions in horses. Unfortunately, once the sand impaction develops it is very difficult to resolve by providing oral medication such as psyllium (Figure 3)  and mineral oil (Figure 4).

Figure 3

Figure 4

The clinical indicators of sand accumulation in horses include intermittent diarrhea, low white blood cell count, fever and plus/minus colic. The sand is abrasive to the lining of the colon which results in diarrhea and sequestration of white blood cells in the colon wall. Horses with sand accumulation within their colons often have a week or month-long history of diarrhea! This is the time to treat the horse with sand clearing products. Once the horse becomes completely obstructed, surgery may be the only option to resolve the impaction. There are several products available to treat horses on a monthly basis as "sand clearing" products however once sand has accumulated within the colon, these products are not effective. They are more effective if used as products to prevent sand accumulation in combination with good pasture management! This condition is treatable but MUST be addressed when clinical signs first develop!!

Equine Hock Arthritis

Figure 1

The radiograph above (Figure 1) is of a horse's hock or tarsus. This view is also known as the "Lateral" view or side view. The equine hock joint is made up of 4 individual joints which are labelled above. The bottom two joints are also known as the distal hock joints and include the distal inter-tarsal joint (DIT) and the tarsal metatarsal joint (TMT). When "injecting" hocks, these are the most common joints treated and are often referred to as the "upper and lower hock joints". Degenerative joint disease (DJD) or osteo-arthritis is most common in the distal hock joints and  often results in poor performance plus/minus lameness. Bog spavin is the term that refers to increased joint fluid within the tibiotarsal joint. This is the "high motion" joint of the hock and is NOT commonly injected with "hock injections". However if increased fluid is noted, a radiographic exam is definitely indicated prior to instituting a treatment plan. Generally speaking, arthritis of the distal hock joints is more acceptable and can be managed with intra-articular therapies. However, arthritis of the tibiotarsal joint and/or the proximal inter-tarsal joint is more concerning and is reason for concern when predicting future performance.

Figure 2

In Figure 2 and 3, there are radiographic changes that indicate osteo-arthritis of the tarsal metatarsal joint space. These changes were noted during a prepurchase exam of a 5 year old horse. The horse was sound during the exam and did NOT respond to hock/stifle flexion. The million dollar question is what to recommend to the buyer based on these findings. In my clinical experience, most horses with these changes will eventually need intervention via intra-articular cortisone injections. I believe that horses with these changes are MORE likely to need hock injections than those with "normal" radiographs. However, these findings are not necessarily a negative prognostic indicator with regards to the horse's future performance. 

With management, i.e, hock injections, these horses can compete at the highest level and succeed!  As such, these findings do NOT constitute a FAILING grade during the prepurchase exam however the buyer needs to be prepared for the strong likelihood of routine "maintenance". This can easily result in hundreds to thousands of dollars per year that should be considered into the price of the horse. 

Figure 3

Guttural Pouch Mycosis in a horse!!

The endoscopic images in Figure 1 and 2 are that of a normal guttural pouch in a horse. There are 2 guttural pouches in the horse and their role is not clearly defined. However, there are several very important structures which course through the guttural pouches. These include large veins and arteries plus critical cranial nerves (Figure 2) . Each guttural pouch is divided into a medial and lateral compartment by a unique bone named the stylohyoid bone. This bone articulates with the base of the skull, just below the ear drum and is part of the support structure for the tongue and larynx! As such, when the horse moves its tongue the articulation between the stylohyoid bone and the base of the skull moves as well. The large blood vessels located within the guttural pouch are important for bringing oxygenated blood to the brain and draining deoxygenated blood from the brain. Equally important are the cranial nerves that course through the guttural pouches. These nerves are essential for a proper swallowing reflex, sensation to the face, and balance.

Figure 1

Figure 2

The endoscopic images in Figures 3-5 are from a gelding that presented for a history of purulent nasal discharge that responded to antibiotic treatment. The endoscopic exam was requested as a follow-up to make sure there was nothing lurking in the horse's upper airway. When the right guttural pouch was entered, a large white plaque was noted covering the entire stylohyoid bone. There was minimal discharge within the pouch and there appeared to be mold covering the surface of the plaque!!

Figure 3

Figure 4

In Figures 4 and 5, the proximity of the fungal plaque with the large blood vessels and important nerves can be seen. Normally, fungi seek out vascular tissue and slowly erode the walls of vessels which can result in low grade bleeding and if it is a large artery, sudden death!! Commonly, horses with fungal infection or mycosis of the guttural pouch present with a history of a bloody nose (epistaxis), however this horse did not. When the plaque was disturbed with the scope, the underlying tissue was exposed and the inflammation was evident.  A bacterial and fungal culture was performed on the fluid recovered during the guttural pouch lavage and a fungi was recovered yet the identity is still being worked out. This condition is difficult to treat and is currently being managed with systemic antifungals and guttural pouch lavage. Stay tuned!!!!

Figure 5

Round Two!! Pharyngeal Phythiosis

Figure 1

The endoscopic image in Figure 1 is from a middle aged quarter horse that presented for abnormal noise during exercise. The entire pharynx is obstructed by multiple granulomas.  Initial biopsy results were consistent with pythiosis and the gelding was treated with systemic anti-fungal medication for several months. 

Figure 2

Recheck endoscopy after 45 days revealed a significant improvement (Figure 2) ; however, treatment was discontinued prematurely and a final endoscopy was not performed.

Figure 3

Over 1 year after the initial presentation, the abnormal noise returned along with bloody nasal discharge. The pale yellow nodules have increased in size and number. Multiple small yellow granuoles are noted through out the pharynx and there is evidence of mild bleeding. The horse will again be treated with systemic anti-fungal medication. A follow up exam to follow!!

Founder!

The images below are of those of a horse with chronic "founder" or laminitis. There has been significant deterioration of the coffin bone and severe distortion of the hoof wall capsule. Clearly, there has not been adequate care of this horse's feet by a farrier/veterinarian team. Chronic founder requires careful attention and care by a veterinarian AND a farrier. The changes in coffin bone alignment must be monitored via radiographs and corrective shoeing by the farrier is critical to reduce pain and further deterioration of the foot. 

The images below are of a different horse with chronic founder that resulted in the coffin bone rotating out the bottom of the foot. Unfortunately, this is the end of the road for this horse and his condition resulted in humane euthanasia. This end result can often be avoided however sometimes despite the most attentive veterinarian/farrier team, mother nature has the last say in the matter. 

This post will be the first of several discussing chronic laminitis/founder, so stay tuned!!!