Your skin can be a window to your underlying health, says Wake Forest University's Joseph Jorizzo, MD, one of the experts who literally wrote the book on skin signs of internal disease. Many underlying health conditions -- some very serious -- first appear as skin problems.
A butterfly rash across the face is often the first sign of lupus. But don't jump to conclusions. "It could be rosacea, it could be contact dermatitis. Unfortunately, sometimes it is a sign of lupus," says University of Miami dermatologist Paolo Romanelli, MD. Only further tests can tell if it's really lupus.
Velvety plaques in the neck and/or armpit suggest diabetes. This condition -- acanthosis nigricans -- could be benign or be caused by obesity. But it is very often a sign of diabetes. In rare cases acanthosis nigricans occurring in other places, such the hands or lips, may indicate an internal cancer.
Leg Plaque: Red on Edge, Gold in Center
Doctors call it necrobiosis lipoidica diabeticorum. As the name suggests, it's a distinctive sign of diabetes, but it is rare. It can first appear as a dull, reddish colored patch but then become shinier with a distinct border. Sometimes the affected skin may crack and become itchy or painful.
Itchy, Violet Bumps on Wrist
Lichen planus is a rash made up of reddish-purple, flat-topped bumps that may itch like crazy. It usually appears on the wrists or ankles, but may be in the mouth or on the lower back, neck, legs, and genitals. The cause isn't known, but if you have it, you may need to get liver tests. It could be linked to having hepatitis C.
Flesh Colored, Orange-Peel Patches on Back
Shagreen patches are flesh-colored lesions on the lower back that have the texture of an orange peel. They often occur with other skin signs: red or brown acne-like bumps spreading across the cheeks and nose; and ash-leaf spots of under-pigmented skin, most often on the trunk, that are oval at one end and pointy at the other. These are signs of a rare genetic disease called tuberous sclerosis that causes benign tumors to grow in the brain and other vital organs.
Tripe palms describes a skin condition in which the skin of the palm becomes thick and velvety-white with pronounced folds in the lines of the hand. The skin resembles boiled tripe. About 90% of cases can be linked to cancer. If only the palms are involved, it may likely be lung cancer. If tripe palms is accompanied by acanthosis nigricans, it's more likely stomach cancer.
'Wooden' Hands and Feet
First described in 1997, nephrogenic systemic fibrosis starts as a brown discoloration and indentation of the lower arms and legs. Very soon, the hands and feet become brown and like wood. Sometimes there's also a small yellow spot in the eye. Researchers only recently found that the dye used during MRI exams triggers this condition in some people with kidney disease.
Scaly Rash on Buttocks, Red Tongue
Fortunately, necrolytic migratory erythema is pretty rare. It's a red, scaly rash, sometimes with small erosions of the skin, more often seen in elderly people. It tends to start in the fold of the buttocks or palms but can be elsewhere on the body. A bright red, painful tongue is common. The condition usually signals a pancreatic tumor, usually a glucogonoma.
Not All Skin Conditions Scary
Most skin problems do not indicate that anything else is wrong with you. For example, granuloma annulare is raised, reddish or flesh-colored bumps forming ring patterns that can be found on the hands and feet. They usually go away within two years and don't mean anything is wrong with you. If it is more widespread, then it may last longer.
Slide (1) Ariel Skelley / Blend Images
Slides (2-5, 7) “Color Atlas of Cosmetic Dermatology”; Marc R. Avram, Sandy Tsao, Zeina Tannous, Mathew M. Avram; Copyright 2007 by The McGraw-Hill Companies, Inc. All rights reserved.
Slides (6, 9,10) Interactive Medical Media LLC
Slide (8) Dermatology Online Journal 13 (3): 24
The International Center for Nephrogenic Systemic Fibrosis Research.
Joseph L. Jorizzo, MD, professor and founding chair of dermatology, Wake Forest University, Winston-Salem, N.C.
Paolo Romanelli, MD, associate professor of dermatology, University of Miami, Fla.
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National Institute of Neurological Disorders and Stroke.
American Academy of Dermatology.
Lupus Foundation of America: "Lupus of the Skin."
American Osteopathic College of Dermatology: "Acanthosis Nigricans."
American Diabetes Association: "Skin Complications."
Cohen, P. Journal of Clinical Oncology, May 1989; vol 7: pp 669-678.
National Kidney Foundation: "Nephrogenic Systemic Fibrosis."
McGevna, L. New England Journal of Medicine, Jan. 7, 2010; vol 362: p e1.
Cyr, P. American Family Physician, Nov. 15, 2006; vol 74: pp 1729-1734.
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