Skin Conditions Associated with GI disorders

Pyoderma gangrenosum

This rare condition causes large, painful ulcers or sores to develop on your skin, most commonly on your legs. It typically presents suddenly as a rapidly enlarging, very painful ulcer often at the site of a minor injury. At first it may look like a small pustule or red bump but then the skin quickly breaks down and full-thickness ulcer forms. Classically, the edge of the ulcer will appear blue or purple, and is very painful.

The exact cause of Pyoderma gangrenosum is unknown; however, it appears to be related to the immune system and some form of neutrophil (or white blood cell) dysfunction. Sometimes it may be caused by, or triggered after, an injury to the skin by a needle prick, biopsy, or insect bite. There may be a genetic predisposition to the condition. It can also be linked to certain diseases or illnesses, and is thought to be a reaction to internal disease.

It’s known to be associated with the following diseases:

  • Inflammatory Bowel Disease (or IBD like Crohns Disease)
  • Rheumatoid Arthritis
  • Certain types of leukemia
  • Chronic active hepatitis
  • BUT about ½ of affected individuals will have NO associated risk factors or underlying diseases.

Pyoderma gangrenosum represents the 2nd most common skin manifestation of Inflammatory Bowel Disease. It is a more commonly associated with ulcerative colitis than Crohn’s disease, and more common in females. Over ½ of IBD patients at the time of skin presentation will have active IBD disease.


Lichen planus

Lichen planus is a T-cell mediated autoimmune disease where the immune system mistakenly attacks your skin and/or mucous membranes.

On the skin, Lichen planus usually appears as firm, shiny, purplish, itchy, flat bumps that develop over several weeks. Some types of lesions may look scaly. It can present anywhere, but is most commonly seen on the front of the wrists, lower back, and ankles.

On mucous membranes, like in the mouth, it can look like white, lacy patches, open sores, or red and swollen tissue. These lesions can be very painful but are not contagious. 

The exact cause of Lichen planus is unknown; however, potential contributing factors may include:

  • Viral infections like Herpes Zoster and Hepatitis C
  • Allergic reactions (for example, to metal or tooth fillings)
  • Physical and/or emotional stress
  • Injury to the skin, and
  • Genetics
  • Lichen planus is associated with Hepatitis C and can be associated with other autoimmune disorders.

The skin form occurs in BOTH men and women equally, but women are twice as likely to get the oral form of the disease.


Diffuse hyperpigmentation or darkening of the skin

Diffuse hyperpigmentation can be caused by:

  • An increase in melanin (or natural pigments found in the skin)
  • An increase in melanocytes (or melanin producing cells in the skin), or
  • Deposits of certain substances in the skin that add color, like iron.

In patients with Hemochromatosis (a genetic condition that causes your body to absorb too much iron), diffuse hyperpigmentation can be seen as a result of excess iron deposits in the skin.


Erythema nodosum 

Erythema nodosum is a painful skin disorder caused by inflammation in the subcutaneous fat (or the innermost layer of your skin). It causes red, painful, lumps or “nodules” most often on the front of the legs below the knees. The nodules range in size from about the size of a dime to that of a quarter. They do not form ulcers.

Generally, the cause is unknown; however, Erythema nodosum can be triggered by strep throat. It may be the first sign of other systemic diseases like TB, fungal infections, sarcoidosis, inflammatory bowel disease, or cancer.

Erythema Nodosum represents the most common skin manifestation of IBD, and is strongly associated with Crohns disease.


Dermatitis herpetiformis

Dermatitis herpetiformis is a rare but chronic, intensely itchy, blistering autoimmune skin condition. The exact cause is unknown; however, the majority of patients with dermatitis herpetiformis (greater than 90%) have celiac disease. It is STRONGLY associated with celiac disease. Celiac Disease an autoimmune disease that occurs in genetically predisposed individuals where consuming gluten leads to damage in the small intestine, malabsorption of nutrients, and increased risk for Enteropathy associated T-cell lymphoma.

There is a genetic component to Dermatitis herpetiformis with a strong association with human leukocyte antigens (HLA) DQ2 and DQ8. Dermatitis herpetiformis is more common in men than women.

The main symptom is a skin rash that comes and goes. It presents symmetrically (so for example on both knees, both shoulders, or both elbows) and is extremely itchy. Patients will often itch it off to the extent that secondary skin thickening and scaring may develop. You might notice small raised areas on the skin called papules, and clear fluid-filled vesicles.

The most common spots for Dermatitis herpetiformis include the elbows, knees, buttocks, back, shoulders, and scalp. These papules or vesicles tend to appear in clusters, which is where the name “herpetiformis” originates from: “herpetiformis” meaning resembling herpes simplex (a viral infection that causes painful blisters to appear in clusters on the skin). Dermatitis herpetiformis, however, is NOT caused by herpes, or any other viral infections. Rather, it is an autoimmune skin condition most often associated with CELIAC DISEASE.

In patients with dermatitis herpetiformis caused by celiac disease, the gliadin fraction of gluten found in wheat, barley, and rye, triggers the production of IgA antibodies causing the immune system to mistakenly target the skin and GI tract, primarily the small intestine.  

Complications of dermatitis herpetiformis associated with celiac disease include:

  • Ulcers in the mouth and/or on the corners of the mouth
  • Dental issues
  • Fatty liver
  • Fertility issues
  • Neurological conditions, and
  • Non-Hodgkin’s Lymphoma: Strict adherence to a gluten-free diet is essential to reducing the risk for this rare but serious, life-threatening complication.


Diagnosis is made by biopsy. Treatment is strict adherence to a gluten-free diet.


Atopic dermatitis

Atopic dermatitis, or atopic eczema, is a condition that makes your skin appear red and itchy. It occurs when the immune system becomes overactive and triggers inflammation that damages the skin barrier resulting in itching, skin rashes and irritation. 

The main symptom is a rash that typically appears on the arms and behind the knees, in the skin flexures, but can appear anywhere on the body. Itching is the hallmark symptom.

In most people, atopic dermatitis first appears in infancy or early childhood and waxes and waves throughout life. Stress, cosmetics, lotions, soaps, creams, and changes in the weather can all trigger flare-ups. It is more common in individuals with a family history of atopic dermatitis or eczema, and a personal or family history of asthma, environmental allergies, hay fever, and/or food allergies.

The skin is one of the organs most often involved in food hypersensitivity reactions.

Food allergies to eggs, milk, peanuts, tree nuts, soy, wheat, fish, and shellfish can trigger symptoms of atopic dermatitis for certain patients. Avoiding food triggers is often essential to minimizing and alleviating symptoms.

Eruptive xanthomatosis

Eruptive xanthomatosis is a condition that causes small, harmless bumps, or eruptive xanthomas, to form on the skin as a result of too much fat or cholesterol in the blood. The bumps are firm, yellow, and waxy and look like little peas. They’re filled with fat. Classic locations include the eyes, face, elbows, and buttocks.

Eruptive xanthomatosis is associated with significantly elevated triglyceride levels. Although the bumps themselves are harmless, the underlying cause of the bumps can be very serious. Significantly elevated triglyceride levels are associated with heart disease and conditions like pancreatitis, which can be life-threatening. Treating the underlying cause of the condition is paramount to your overall health and longevity.

Contact Us