The skin is the largest organ of the body. It covers almost all of an animal's body, protecting it from the external environment. Any external insult would have to pass through the skin's defences first before making its way into the body. Occasionally, external insults do penetrate the skin and give rise to skin diseases. Skin problems are quite commonly encountered, especially in Singapore's humid climate.
Allergies make up a large portion of the cases. The general mindset of most owners is that their dog has food allergies. They are always quick to blame the diet. However, environmental allergies and even flea bite allergies occur more frequently than food allergies.
Allergy is the hypersensitivity of the body's immune system to seemingly harmless allergens in the environment. The most common allergen for dogs in Singapore is house dust mites. Pollen allergy is also common in Singapore, particularly from grasses and oil palm trees.
To better understand an allergy, a good history account is required from the owner. Information such as previous responses to steroids and antibiotics would help in the diagnosis. There is no diagnostic test for allergies. Hence, a systematic trial and elimination process is required to identify the allergy. Most owners usually bring their pets to the vet only after the animal falls sick or if the skin problem gets severe. With allergies, a vet would usually like to see the animal when it is doing well. This gives the vet a better indication as to whether a drug or treatment is working, and helps to better identify the allergy.
Steroids, antibiotics, antifungals and antihistamines are usually used to treat infections associated with allergies. As an allergy is incurable, good owner compliance is required. A multi-centric approach is used to manage allergies, such as reducing exposure to allergens, skin barrier protectants, shampoos, conditioners, omega oil supplements and sometimes even alternative medicine such as Traditional Chinese Medicine.
Heat rash, moist dermatitis and Schnauzer bumps are some of the names given to the 'pimples' and bumps that we see on our dogs' skin. These are caused by external insults to the skin causing itching, which in turn results in scratching and secondary bacterial infection or even secondary fungal infection. External factors may include environmental allergens, contact allergens, warm weather and humidity or even procedures that may cause irritation to the skin such as grooming.
A good history is again required to assess if the skin rash is a short-term or long-term problem. This helps to differentiate between a recurring allergy and a simple bacterial infection. These conditions are often treated with steroids, antibiotics and antifungals. Shampoos with antiseptic properties are helpful in reducing the bacterial count on the skin to prevent recurrence. Omega oil supplements are used to help reduce skin inflammation.
Fleas, ticks and mites are some common parasites that cause skin problems. Ticks not only cause skin irritation with their bites, they also spread blood-borne diseases such as tick fever. In a tropical climate like Singapore's, it is impossible to completely eliminate the parasites from the environment. Flea bite allergy is common in Singapore.
Fleas are also very difficult to eliminate from the environment. Their eggs are resistant to drying and they only stop reproducing at temperatures below 17 degrees Celsius. Due to our large community (stray) cat population, the flea life-cycle persists in the environment.
Prevention is the best form of control and there are many different products on the market that can be used. Beware of some pet shops' ectoparasite medications, as they can cause seizures when applied. Check with your vet to find out which products are safe for your pet.
Hormonal skin problems are also commonly seen in private practice. The common hormonal diseases that cause skin problems are hypothyroidism and hyperadrenocoriticism.
Hypothyroidism is the inadequate production of the thyroid hormone. This usually only happens in dogs. This would lead to the slowing down of the metabolic rate, lethargy, thinning of fur and hair loss, particularly over the body and sides of the animal. A blood test is required to check the thyroid function of the dog. If thyroid production is inadequate, lifelong supplementation of thyroid hormone is required.
Hyperadrenocorticism, also known as Cushing's disease, is the overproduction of a steroid hormone, cortisol, by the body. This leads to increased appetite, thirst and urination. It also causes thinning of the skin and fur. It gives the animal a pot-bellied appearance. Blood tests are required to confirm the disease. When diagnosed, long-term medication is again required to control the amount of cortisol production. Long-term management of these hormonal diseases is usually fair to good.
There are people who think that their dogs get skin problems because they had been sterilized. Others have even claimed that their dogs were menopausal, and hence had developed skin problems. This is not true. Dogs do not get menopausal because they do not have a 28-day cycle like human females. They only get a three-week spike of hormones when they are on heat and the rest of the time nothing happens. Hence they are not as reliant on sex hormones as humans are. Besides, sex hormone-deficient skin diseases are rare.
Skin diseases can be frustrating, and different skin problems may often look the same. It is important to have a systematic approach to identify and then manage these skin diseases.