Skin Signs of Gastrointestinal Disease

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List some of the hallmark skin signs seen with diseases of the digestive tract

• Cirrhosis: Jaundice, ascites, purpura, spider angiomas

• Peutz-Jeghers syndrome (PJS): Lip lentigines

• Inflammatory bowel disease: Pyoderma gangrenosum (PG)

• Gardner syndrome: Osteomas, epidermoid cysts

Many diseases of the skin also involve the oral and anal mucosa. Embryologically, the foregut (forming the oral epithelium) and the hindgut (creating the anal mucosa) share a common ectodermal component in the first few weeks of fetal development. Therefore, it is entirely logical that some diseases that affect the gastrointestinal (GI) system also affect the skin.

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What is jaundice (icterus) and when is it apparent in the skin?

On average, 250 to 350 mg of bilirubin are generated each day, with 70% to 80% arising from senescent red blood cells and the remainder coming from heme proteins in the bone marrow and liver. Jaundice is the overaccumulation of bilirubin and various bile pigments in the skin and other organs. It may arise from obstruction in cholelithiasis, hemolysis with overproduction of bilirubin, ineffective erythropoiesis, or intrinsic liver disease. Clinically, jaundice is first apparent in ocular sclera, the skin of the face, and the sublingual tongue. The condition is best appreciated in bright daylight and may be overlooked indoors. Jaundice is not clinically apparent until serum bilirubin approximates 2.0 to 2.5 mg/dL in the adult and 5 mg/dL in the neonate. Jaundice may be the first sign of hepatic dysfunction. Conversely, yellowed skin, with normal white ocular sclerae, may be seen with carotenemia (excessive beta-carotene from carrots, squash, and sweet potatoes), lycopenemia (tomatoes, beets, and berries), and the drugs quinacrine and busulfan.

Frew JW, Murrell DF, Haber RM. Fifty shades of yellow: a review of the xanthodermatoses. Int J Dermatol . 2015;54:1109–1123.

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What can the shade of jaundice reveal about the type of liver disease in a patient?

Yellow discoloration of the skin is caused by bilirubin. More orange shades come from xanthorubin (intrahepatic jaundice). A deep green color is due to marked biliverdinemia and is characteristic of obstructive jaundice, such as that caused by pancreatic cancer. Patients with hepatobiliary disease, especially obstructive jaundice, often have severe pruritus. Constant scratching results in inflammation of the skin followed by postinflammatory hyperpigmentation. Postinflammatory hyperpigmentation in the presence of bile pigments imparts a bronze color to the skin. “Bronzing” is also encountered in hemochromatosis and primary Addison disease. The differential diagnosis of jaundice includes carotenemia, lycopenemia, infections with Clonorchis sinensis (travel to Asia) or Fasciola hepatica (ingesting watercress), and the sallow skin of myxedema.

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List the top 10 skin findings suggestive of hepatic and biliary tract disease

Hepatobiliary diseases can be associated with alterations of the cutenaous vasculature, such as spider angiomas, palmar erythema, and cutaneous varices. Spider angiomas are classically associated with chronic liver disease, yet these lesions may also be seen in pregnancy, oral contraceptive use, and in normal persons, especially children. In chronic liver disease, spider angiomas may be numerous on the face, neck, upper chest, hands, and forearms. “Liver palms” refers to the mottled erythema and increased warmth of the palms (and sometimes the soles of the feet) in chronic liver disease. Palmar erythema also may be seen in pregnancy, lupus erythematosus, pulmonary disease, and hyperthyroidism.

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What are the most common cutaneous findings associated with portal venous hypertension?

Portal venous hypertension due to chronic liver disease leads to collateral circulation, with esophageal varices, as an example. In the skin, this same phenomenon may lead to dilation of abdominal wall veins ( Fig. 36.1 ). Caput medusa refers to the dilated periumbilical veins and has been known for centuries as a marker of advanced liver disease. In men with chronic liver disease, induction of a “hyperestrogen state” (due to a decreased estrogen breakdown in the diseased liver) leads to gynecomastia; testicular atrophy; loss of axillary, truncal, and pubic hair; and a female pattern to the pubic hair. Purpura, ecchymoses, and gingival bleeding reflect impaired hepatic production of clotting factors, especially the vitamin K–dependent factors. Peripheral edema and ascites indicate hypoalbuminemia and/or portal venous hypertension.

6

What is the most common skin symptom associated with liver disease?

In liver disease, pruritus is common. Primary biliary cirrhosis, diseases caused by biliary tract obstruction, and cholestatic jaundice may have severe pruritus. Moreover, constant scratching may lead to excoriations, pigment disturbances, and lichenification of the skin.

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What skin signs may be associated with GI bleeding?

See Table 36.1 .

8

What is pyoderma gangrenosum?

PG is a severe ulcerative condition that is associated with inflammatory bowel disease, autoimmune hepatitis, rheumatoid disease, and lymphoproliferative disease. The condition is more common in women, and in 70% of cases it affects the lower legs ( Fig. 36.2 ). PG begins as a small, tender pustule that breaks down quickly to form a painful and rapidly expanding necrotic ulcer with a undermined violaceous edge. The condition manifests pathergy , which his development of skin lesions at sites of minor trauma. The ulcers of PG may become quite large and deep and may even become circumferential and threaten a limb. Lesions frequently heal with a thin, atrophic scar.

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