Superficial bacterial folliculitis is an infection of the hair follicles of the skin. It is caused by bacteria (most often Staphylococcus pseudointermedius). The condition is common in dogs, but rather rare in cats. There is no predisposition to race, age or sex. Any region of the body can be affected (abdomen, inner thighs, armpits, back, sides, etc.). The problem can be either localized or generalized.
Superficial bacterial folliculitis can also be primary or secondary (underlying cause). Actually, certain health problems, sometimes unapparent, can predispose your pet to developing a bacterial folliculitis by reducing the effectiveness of his cutaneous barrier (skin weaker and more prone to infections). If there is an underlying cause and it is not identified or addressed, it is probable that the bacterial folliculitis becomes recurrent. Numerous underlying causes are possible: food allergies, environmental allergies, parasite infections, hypothyroidism, hyperadrenocorticism (Cushing disease) etc.
Your pet may present numerous clinical signs with a superficial bacterial folliculitis: itching, small red and/or white bumps (often in the form of targets), crusts, fur loss, blackish coloration of the skin and/or thickening of the skin.
A skin scraping (a sample from the skin analyzed under the microscope) may be performed in order to confirm the presence of bacterial overgrowth, although a diagnosis is often possible based simply on the physical exam. In certain cases, your veterinarian will recommend doing a bacterial culture in order to determine exactly the type of bacteria involved as well as its sensitivity to different antibiotics. The bacterial culture is a test that should be performed in an external laboratory.
The treatment for a superficial bacterial folliculitis consists of the administration of antibiotics given orally. An improvement is generally denoted during the first week of treatment, but it is primordial to continue giving the antibiotics 1 week following the complete healing of the skin in order to ensure that the infection is well resolved. A treatment of 3 to 4 weeks is generally sufficient, but may sometimes need to be prolonged up until 6 to 8 weeks. Stopping the treatment prematurely stimulates the development of antibiotic resistant bacteria; therein lies the importance of giving the entire treatment as prescribed.
An antibacterial shampoo and/or calming solution can sometimes be recommended in order to accelerate healing or even improve the comfort of your pet. In certain cases when the itching is severe, an oral form of cortisone (prednisone or prednisolone alone or combined with an antihistaminc) may be prescribed in order to give your pet some relief.