REACT Equine Allergy Clinic - Allergic Diseases



		COPD / RAO Chronic Obstructive Pulmonary Disease or Recurrent Airway Obstruction may also be known as Heaves, Broken Wind and Equine Asthma… COPD / RAO Chronic Obstructive Pulmonary Disease or Recurrent Airway Obstruction may also be known as Heaves, Broken Wind and Equine Asthma. These terms relate to inflammatory airway disease (bronchitis and/or bronchiolitis), which is a progressive and recurrent illness due to hypersensitivity or allergic reaction of the airways to inhaled substances and particles. The inflammation is characterised by increased mucus production, thickening of the mucosal lining and bronchoconstriction, which results in narrowing of the airways and reduced oxygenation of the blood. In mild cases this may only cause a loss of performance with no other symptoms, while very severe cases will be compromised even at rest. The common symptoms are coughing, a nasal discharge, an increased abdominal effort on breathing out (Heave) and exercise intolerance. Most often it is a disease of stabled horses where stable dust contains causative allergens such as fungal spores from hay and straw, and dust mite faeces. Less commonly it is caused by pollens in the spring and summer, when it is known as Summer Pasture Associated Obstructive Pulmonary Disease (SPAOPD). This often manifests as a particularly severe and acute disease that can be very difficult to control because it is so difficult to avoid airborne pollens. The main drugs used in treatment are corticosteroids (inhaled or systemic) and bronchodilators such as Ventipulmin. Allergy neutralisation is very successful at treating this disease and offers an economic long-term solution to the problem that does not involve the use of drugs which can have harmful side effects. URTICARIA Otherwise known as Hives, Nettle Rash or Protein Bumps. This is a common skin allergy characterised by sudden onset raised oval skin bumps… Urticaria Otherwise known as Hives, Nettle Rash or Protein Bumps. This is a common skin allergy characterised by sudden onset raised oval skin bumps, which often become doughnut-shaped. Severe cases become covered all over the body with large bumps that can ooze serum. The horse is mildly itchy but can become somewhat depressed in long standing cases. Secondary bacterial infections can take hold when the skin becomes broken. Riding and competition is often prevented due to the unsightly appearance and rubbing by tack. A wide variety of allergens can be implicated and include foodstuffs and substances coming directly into contact with the skin, but food allergies are often implicated. Treatment usually consists of corticosteroids, combined with elimination diets and bedding changes. A lot of cases are resolved in this way, but a significant proportion become recurrent and long-standing, which is when allergy neutralisation becomes an very effective cure. Atopy Atopy is another much less common allergic skin disease that is characterised by a severe itch with little in the way of abnormal appearance to the skin… Atopy Atopy is another much less common allergic skin disease that is characterised by a severe itch with little in the way of abnormal appearance to the skin. It is a challenge to diagnose correctly and relies on elimination of other itchy skin diseases (such as mange or lice infestation) and characteristic pathology seen on skin biopsy. In most cases it is a serious problem with self-mutilation due to the intense itch causing severe damage to the skin. Managing these cases is often very difficult without using high doses of corticosteroids for a long time, which carries a high risk of side effects. Allergy neutralisation is an effective therapy in most cases. Headshaking Headshaking is characterised by persistent and sometimes violent abnormal shaking of the head, particularly when ridden… Headshaking Headshaking is characterised by persistent and sometimes violent abnormal shaking of the head, particularly when ridden. There are many different causes of headshaking and precise diagnosis of the cause can be very difficult. Indeed, the syndrome is not fully understood and a cause is often not identified. The fact that many horses do not show symptoms in the winter but start in the spring and continue through the summer suggests that allergies are involved and it has been likened to Hay Fever in humans. At this stage, horses tend to respond to corticosteroids, which supports the allergy theory. However, whilst allergies seem to be involved in seasonal cases, long-standing cases often seem to be due to pain, perhaps like a migraine, caused by bright sunlight, or discomfort due to nerve pain (neuralgia) of the Trigemminal nerve in the head. This is an extremely frustrating disease for horses, riders and vets with most cases being untreatable and the horse rendered unrideable. REACT has had some success in treating these cases, but success is much higher if they are seasonal headshakers and respond to cortisone i.e. the hay fever type. Sweet Itch Also known as Summer Excema or Summer Seasonal Recurrent Dermatitis. Sweet Itch is a disease caused by allergy to the saliva of biting midges… Sweet Itch Also known as Summer Excema or Summer Seasonal Recurrent Dermatitis. Sweet Itch is a disease caused by allergy to the saliva of biting midges, principally of the Culicoides genus, which has some 200 species in the northern hemisphere. The disease is characterised by intense itching of the mane and tail base in particular, but some horses have reactions along the underside of the belly or even over the whole body. As relief is sort by constant rubbing, the hair is lost and the skin develops a ridged and scaly appearance. The disease can become seriously debilitating with nasty skin lesions and secondary infections. All horses can develop this disease but as cobs, ponies and Icelandic horses are particularly prone, there is almost certainly a genetic susceptibility. Treatment is generally aimed at avoiding midge bites by stabling, fly repellents and whole body mesh rugs. Corticosteroids are effective but required for long periods and at high doses and therefore, their use is tempered by the significant risk of side effects such as laminitis, especially in ponies. REACT Equine Allergy Clinic has attempted treatment in a number of individuals and carried out a blind placebo controlled trial. The results are equivocal, but many owners have reported that whilst their horses were not cured, their symptoms improved such that the disease became manageable. The main hindrance to truly effective treatment may well be the allergen used which is too crude, being made from whole Culicoides insects rather than specific salivary antigens.