Sunday September 21, 2008

Show me some skin

AGE WELL By Dr TING HOON CHIN

The skin as a mirror of internal diseases.

WHILE the eyes may be the window to the soul (implying that a person's thoughts can be ascertained by looking in his or her eyes) the skin can be a mirror of internal diseases if we know what to look for. With some good medical training, one does not need the sophisticated gadgetry of a CSI laboratory in New York or Miami or the miraculous skills of a Dr House to decipher the clues!

Some important tell-tale clues to look for are:

1. Presence of certain "lumps and bumps" on the skin

2. Abnormal colour

3. Abnormal blood vessels

4. Hair changes

5. Unexplained itch

Lumps and bumps

Xanthelesmata is a common condition in which yellowish small flat lumps appear around the eyes. This is often a sign of raised blood cholesterol levels, especially if it is extensive and occurs in young patients.

In some cases, however, especially if it starts in middle or old age, the cholesterol level may be normal.

Xanthelesmata is the most common type of a group of abnormal skin lumps called xanthomas, which represent collections of abnormal cells called histiocytes that contain excess fat and are related to abnormal blood lipid levels (mainly cholesterol and triglycerides). The lumps can vary in size from 0.5cm to 2.5cm or more.

Such lumps can occur as firm yellowish nodules on the knees and elbows (tuberous xanthomas), diffuse swelling along tendons, especially the Achilles tendon (tendon xanthomas), flat lumps on the neck, chest and palms (plane xanthomas), and transient crops of brown/red small lumps on the buttocks (papulo-eruptive xanthomas).

Reddish fleshy lumps in the skin may sometimes be caused by secondary deposits (metastases) from internal cancers like those of the breast, lung and stomach. Other malignances like leukaemias (especially monocytic leukaemia), lymphomas and sarcomas can leave similar deposits in the skin.

Brownish round or elongated lumps in the skin, if associated with brown freckle-like spots, can be a sign of a disorder called neurofibromatosis.

The lumps can be enormous, resulting in gross disfigurement €" the "elephant man" featured in the awarding-winning movie had this disease. The disfigured young man with a bulging forehead in a recent House TV episode had the same condition.

In 40% of cases there is associated neurological abnormalities like tumours in the brain, spine and nerves. There can also be endocrine abnormalities (e.g. precocious puberty, acromegaly), gut abnormalities (e.g. intestinal bleeding) and cancers (e.g. sarcoma).

Abnormal colour

Darkening and thickening of the skin around the neck, armpits and groin (acanthosis negricans) is a fairly common skin abnormality. This can be hereditary, in which case, the abnormality starts in infancy and usually regresses after puberty. It can be related to obesity, and is seen more often in people with dark complexion.

However, if the darkening and thickening of the skin is severe; the onset is in adulthood; the patient is not obese; and there is associated intense itching, then there is a high chance that the patient has an internal cancer. In 90% of cases the cancer is within the abdomen, especially in the stomach. Occasionally the cancer can be in the lung, thyroid and lymph node (lymphoma).

In acanthosis negricans, the darkening of the skin is localised to certain areas. Generalised grayish/black darkening of the skin all over the body, on the other hand, can occur in diseases like cancers e.g. melanoma, lung cancer (especially the oat cell type), and malignancies of the pancreas, thyroid, breast and ovary, as well as in chronic liver disease.

Diffuse brownish discolouration of the skin can occur in a condition call haemochromatosis, in which there is excessive deposition of iron in the skin as well as internal organs. The condition is associated with diabetes and hardening of the liver (cirrhosis). The skin discolouration may precede the diabetes and cirrhosis of liver by many years.

Diffuse bronzing of the skin with small paler spots called "rain-drop pigmentation" is a sign of chronic arsenic poisoning. Another sign consists of hard little corn-like growths on the skin, particularly of the palms and soles (arsenical keratoses).

The arsenical keratoses can develop into skin cancers (usually squamous cell carcinoma). Patients with such skin abnormalities are also more likely than normal to develop cancers in the internal organs. The source of the arsenic could be from medicine, e.g. Fowlers solution, which was popular for treatment of psoriasis; exposure to arsenic-containing herbicides and insecticides in agricultural activities; and contaminated well water.

In the Middle Ages and Renaissance periods, arsenic was a favourite murder weapon. Some scientists still believe, for instance, that Napoleon was poisoned to death with this substance when he was incarcerated at St. Helena, though recent examination of his hairs from various ages by nuclear means suggests that there was already excessive amounts of arsenic in his hair before his imprisonment at St. Helena.

Abnormal blood vessels

Abnormal blood vessels can give rise to different signs in the skin. The port-wine stain is due to abnormally large blood vessels in the upper part of the skin (just below the epidermis). It appears as pinkish to dark red, flat patches, most frequently on the face. Associated eye and brain abnormalities occur in 8-15% of patients with port-wine stain.

The most important associated eye abnormality is glaucoma in which there is raised pressure of the fluid inside the eye. This can cause loss of vision. The brain abnormalities are due to abnormal blood vessels in the membranes covering the organ. The affected patients often develop fits and sometimes weakness of the limbs and mental retardation.

Spider naevi are abnormally prominent small reddish blood vessels in the skin with a central round spot (like the body of a spider) and fine reddish lines radiating from it (like the legs of a spider). These naevi are commonly found on the upper back and upper arms. When more than five such "spiders" are found, it can be sign of chronic liver disease.

Telangiectasia refer to visible small red linear small blood vessels in the skin. When telangiectasia are found with redness on the skin of the nail folds (the skin covering the base of the finger nails) it can indicate the presence of a connective tissue disease like systemic lupus erythematosus (SLE) or dermatomyositis.

In SLE, there are often abnormalities in multiple organs like the joints, kidneys, lung and nervous system. The face of a patient with SLE often has a "butterfly rash" with erythema over the nose and cheeks like the body and wings of a butterfly.

In dermatomyositis, the systemic abnormalities are mainly in the muscles (weakness and wasting), heart (myocarditis) and lungs.

Hair changes

Diffuse loss of hair can be due to systemic diseases. In hypothyroidism (inadequate production of the hormone thyroxin by the thyroid gland), diffuse hair loss may be the only sign of the hormone deficiency. Anorexia nervosa, iron-deficiency, SLE and many severe chronic illnesses like cirrhosis of liver and internal cancers can all have the manifestation of diffuse hair loss.

Certain venereal diseases can also present with hair loss e.g rather patchy hair loss with a "moth eaten" appearance in secondary syphilis and premature generalised thinning and graying of the hair in AIDS (acquired immunodeficieny syndrome).

Unexplained itch

When a person complains of persistent and severe itch without an apparent cause, we would need to consider whether a systemic illness could be the underlying cause.

In severe kidney disease the patient can have dry skin with severe itch. A clue to the existence of kidney failure is a "sallow" complexion €" paleness with a tinge of yellow.

In chronic liver disease, especially if it is due to obstruction of the flow of bile, there can be intense itch. Sometimes internal malignancies like lymphomas can present with generalised itch.

In this age of AIDS, when a person presents with generalised itch and many excoriated little lumps in the skin, AIDS should also be considered a possible cause.

Conclusion

If a person develops unusual signs in the skin it is prudent to have them checked by a doctor in case they are indicators of more serious internal diseases!

This article is contributed by The Star Health & Ageing Panel, which comprises a group of panellists who are not just opinion leaders in their respective fields of medical expertise, but have wide experience in medical health education for the public.

The members of the panel include: Datuk Prof Dr Tan Hui Meng, consultant urologist; Dr Yap Piang Kian, consultant endocrinologist; Datuk Dr Azhari Rosman, consultant cardiologist; A/Prof Dr Philip Poi, consultant geriatrician; Dr Hew Fen Lee, consultant endocrinologist; Prof Dr Low Wah Yun, psychologist; Datuk Dr Nor Ashikin Mokhtar, consultant obstetrician and gynaecologist; Dr Lee Moon Keen, consultant neurologist; Dr Ting Hoon Chin, consultant dermatologist; Prof Khoo Ee Ming, primary care physician; Dr Ng Soo Chin, consultant haematologist. For more information, e-mail
starhealth@thestar.com.my. The Star Health & Ageing Advisory Panel provides this information for educational and communication purposes only and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader's own medical care.

The Star Health & Ageing Advisory Panel disclaims any and all liability for injury or other damages that could result from use of the information obtained from this article.