Pyoderma gangrenosum is an inflammatory skin disease characterized by lesions on the skin. It most often affects people aged 25 to 55.
What is pyoderma gangrenosum?
Pyoderma gangrenosum is an inflammatory skin pathology of immune origin. Relatively rare, this disease is due to une abnormality in the functioning of polynuclear neutrophils, defense cells in our body that respond to various stimuli. “In this case, they are hyper stimulatedwhich will cause them to produce a lesion on the skin which begins with a small red, painful papule, which looks like a pimple and which will gradually ulcerate. It is torpid, sometimes associated with a slight fever“, informs us Dr. Marc Perrussel, dermatologist. Classically, the lesions are preferentially located at the level of lower limbs (hip, thigh, leg, foot). Pyoderma gangrenosum usually affects people aged 25 to 55 years old.
What causes pyoderma gangrenosum?
“The cause of pyoderma gangrenosum is unknownbut it will be expressed in certain situations of comorbidities which are concomitant with the presence of certain cancers, in particular certain hematopoietic disorders such as leukemias and certain inflammatory diseases such as inflammatory rheumatic diseases (rheumatoid arthritis) and certain inflammatory digestive diseases such as Crohn’s disease or the ulcerative colitis“, explains the dermatologist. Pyoderma gangrenosum can also occur in certain skin diseases such as Verneuil’s disease. The disease can also develop after an injury or surgery. On the other hand, it is not an infectious disease, there is no particular bacterial proliferation. “If we take a sample, it is polymorphic, several bacteria are found”, he adds.
Pyoderma gangrenosum and Crohn’s disease: what is the link?
Pyoderma gangrenosum may be an extra-digestive manifestation of Crohn’s disease, a chronic inflammatory bowel disease that occurs by pushes, interspersed with phases of remission. This condition is linked to a dysregulation of the immune system which leads to damage to the tissues of the digestive tract.
What are the treatments ?
The treatment is based, firstly, on applying dressings at the level of the lesions to promote healing. Of the topical corticosteroids can be applied to recent, shallow lesions. In cases of severe disease, oral prednisone may be prescribed. “TNF alpha blockers such as infliximab, adalimumab and etanercept are administered to block the runaway immune system”, says Dr. Marc Perrussel. These immunoregulatory drugs are particularly useful in patients suffering from chronic inflammatory bowel disease. “On the other hand, local traumatic interventions, particularly surgical excisions, should be avoided as this would aggravate the lesions.“, warns our expert.
What is the healing time?
The course of the disease is torpid and despite local antibiotic treatments, it does not tend to resolve quickly. In some cases, healing does not occur, even after a few months of treatment.