There are many different types of skin lesions that can occur in the skin of dogs. And each lesion or combination of lesions can be caused by multiple diseases and conditions.

Some lesions are a manifestation of a dermatological disease while others are a manifestation of an internal disease. As an example dogs may develop ulceration in the mouth and crusting on their feet as a manifestation of liver disease or pancreatic tumor.

In other cases skin lesions are manifestation of an auto-immune disease (e.g. lupus) and life long immunosuppressive treatment is necessary.

Red itchy bumps (papules) may be caused by diseases like bacterial infection (superficial pyoderma), dermatophytosis (ringworm), demodicosis (red mange), scabies (sarcoptiform mange), food allergy, and contact allergy may need to be considered. The history and the distribution of the lesion will help differentiate between these diseases.

Non-healing draining wounds (nodules and draining tracts) may be caused by diseases like deep bacterial infections, fungal infections or neoplasia (cancer) may have to be considered.

Some lesions are primary (caused directly by the disease process) while others are secondary (such as self-inflicted) or are just a manifestation of chronic itchy skin.

Most of skin lesions or sores are secondarily infected with bacteria and it is likely that your dog may require weeks of antibiotic to resolve the secondary bacterial infection.

Diagnosis

There are a variety of causes for skin lesions and sores. A thorough physical exam and various diagnostic tests can help determine the cause and direct treatment.

History is very important in diagnosing skin diseases. Your veterinarian will ask questions regarding the age of onset, progression of disease, travel history and response to previous treatments. Since animals can develop reactions to drugs they have been receiving for a long time, be sure to include information about all supplements and medications your dog has been receiving.

Examination of the exudate (discharge) under the microscope (cytology) can provide useful information. Your veterinarian may take samples of the exudate and stain slides.

Biopsies are often necessary to establish a final diagnosis. Some samples may be used for cultures, while others may be sent to the pathologist to obtain more information about the cells that are present in the skin. This is a fairly safe procedure and sutures can be removed after 7-10 days.

Home Care

Early diagnosis is very important, thus if your dog has skin sores, seek your veterinarian's help without any delay. Some disease can be treated successfully if caught early but prognosis may become poor in advanced cases.

You may have to use medicates shampoos depending on the type of infection diagnosed.

You may have to administer oral medications for pronged period of times, as skin infections take a long time to clear. It is not uncommon for animals with deep bacterial infection to require antibiotics for 2 to 4 months. Compliance plays an important role in determining the success of treatment.

If your dog has open sores, do not allow him/her to go swimming, as the sores are an open door for additional, sometimes life-threatening infections (Pythiosis).

Some infections are transmissible to people or other animals. If you are not sure about the nature of the infection, ask your veterinarian about the risk for contagion. In most cases, it is safest to avoid contact with children, elderly people or people undergoing immunosuppressive treatment (e.g. chemotherapy) as they may develop disease with organisms that routinely should not be a hazard to others.