INGROWN TOENAILS: ANY WAY YOU CUT IT

by James Channing Shaw, MD

Twenty-five years of practice in dermatology has taught me that ingrown toenails have little or nothing to do with whether nails are cut straight across or with a curve. What you mostly read is 'cut toenails straight or you'll get ingrown nails'. The message comes from supposed experts such as podiatrists and doctors. Every child on the face of the earth grows up thinking this. And why not? They hear it from grown-ups who must know everything. Grown-ups, after all, are supposed to know stuff.

Once again, I am here to dispel another myth: the myth of the straight-cut toenail. There is no evidence to support the notion that cutting nails with a curve causes ingrown nails, or that cutting straight prevents them. Those who preach straight-cut are merely perpetuating unsubtantiated traditional beliefs. Studies have not been done and closer examination of the rationale exposes its faults.

In every case I've seen, and there have been many, patients have always done exactly as they were told: they cut their toenails straight across and still developed ingrown toenails. Ingrown nails are more about an individual's own anatomy, plus, in some cases, trauma from shoes.

The photograph below shows a typical ingrown toenail. The nail is straight-cut, but the ingrown nail goes nearly to the cuticle. The manner in which the nail was cut couldn’t have influenced the ingrown nail close to the cuticle.



What, then, is an ingrown nail? Most importantly, it appears NOT to be an infection in the true sense, i.e. caused by bacteria. Most cases of ingrown nail don't respond at all to antibiotics. Instead, an ingrown nail results when the tissues at the side of the nail get irritated, inflamed, and swollen, leading to redness, pain, and tissue breakdown with oozing and pus. There is one exception: if you cut too close and injure the skin, you can introduce real infection, but it behaves differently: more rapid in onset, more painful, and responds to antibiotics.

It is thought that the sides of the nail must play a role in ingrown nails, that the edge 'digs' into surrounding tissue, either naturally or from shoe pressure. We know this because the problem goes away when the lateral sides of the nail or excess nail fold skin are permanently removed by surgery. Whether from the nail itself, or excessive surrounding skin, the individual's reaction to microscopic trauma is probably a key factor.

What makes NO sense is the belief that cutting the nail influences how a nail grows. If that were the case, we might expect to see it happen with finger nails, but we don’t: fingernails and toenails grow out regardless of how they are cut. Nails grow by sliding horizontally outward from the cuticle area. Whether you cut straight or curved, the nail still slides toward the tip in the way it is genetically programmed to do. The white part that gets clipped away has already separated from its base (the nail bed), and even if you cut too close, it cannot influence how the nail grows.

The big question is whether we have ANY control over preventing ingrown toenails. My suspicion is that we do not. Reasonable hygiene (but not too aggressive) is as much as we can recommend. Plenty of toe space in shoes also seems wise (but not proven). All definitive treatments, however, involve surgery, although many devices and practices to flatten out the nail have been tried with mixed results.

It would be good if someone did a scientific study of curved cut versus straight cut, but since this is a non life-threatening condition, it’s not likely to happen. In the meantime, if you would like some contour with your pedicure, give it a try. If you have never had ingrown nails, the odds are in your favor. Go easy at first. A little rounding of the edges of the big toenail won't hurt you.

WINTER ITCH AND WINTER DRY SKIN

                                                                         James Channing Shaw, MD

If you look with a magnifying lens at very dry skin, it looks like a dry lakebed, with multiple shallow cracks. The medical name for this dryness is xerosis. How does xerosis happen, who gets it, and what can be done to treat it?

Normally the skin acts as a barrier to evaporation; water is prevented from escaping by the top most layer of the skin called the stratum corneum. In this layer skin cells are stacked on top of each other, each one overlapping the ones below. Each stratum corneum cell contains material called keratin that is nearly impermeable to water. Between the cells is a mixture of lipids (fats), called the lipid layer.



This multlayered sandwich of cells and lipids creates an armor that protects against water loss. However, since we are all different, some individuals have better functioning stratum corneum than others and are better protected from drying out. Those of us who are genetically unlucky in this regard are susceptible to dry skin, primarily from two environmental causes. One is decreased humidity in the air and the other is a damaged lipid layer. Low humidity pulls water from the cells of the stratum corneum, making them brittle, curled at the edges, and separated. Add wind to the dry air and the problem gets worse.


Damaged lipid layer comes from chemicals on the skin that wash away the lipids. Our hands are the most susceptible to this kind of damage because they have the least amount of lipid in the stratum corneum layer. Ironically it is our hands that get most exposed to chemicals such as soap and detergents. Solvents like alcohol, cleansers, and ammonia are even worse. With the amount of hand washing we have all been taught to do, it is no surprise that dry cracked hands are a common problem in the winter.

Severe xerosis: this case has become erythema craquelé

 
Why is winter air such a problem? Two reasons: 1) cold air holds less moisture than warm air, and 2) artificial heat in our homes dries the air to extremes. Indoor humidity of less than 10% is common during a cold winter. Only the heartiest of stratum corneum can withstand this desert-like effect without becoming dry and cracked.

When skin dries out, most people start itching. The shins and the lower back are the most common places for ‘winter itch’. Faces and lips can also become dry, flaky and cracked. The hands are different: finger tips can split and are very painful. While this can be annoying and uncomfortable, the good news is that very little serious illness comes from skin dryness.

So….what to do? There are basically two ways to minimize the problem: 1) increase humidity in the air, and 2) provide skin barrier protection against water loss. A vacation in the tropics returns skin to normal within a week or two. The increased humidity in the warm air of the tropics stops water loss from skin. A humidifier, while not as good as a tropical environment, can be helpful in your home. For dry cracked hands, a lesson from feet is instructive. Feet don’t dry out as commonly as hands because they are protected all day in warm humid shoes and socks. Gloves provide the same protection for hands that sox do to for feet. Soft comfortable gloves, not rubber gloves, are best. The goal is to increase humidity, not cause perspiration and soaking.

For more skin barrier protection, additional ‘lipid layer’ needs to be applied. There is an important lesson here concerning lotions, creams, and ointments. Lotions are mostly water with some oil (lipid) and when applied to the skin, the water evaporates leaving a small amount of oil remaining. This gives the false impression of 'absorption', but lotions help only in the mildest cases of dryness. Severe dryness calls for thick creams (less water, more lipid), or ointments like petroleum jelly (all lipid, no water). The greasy ointments give the best protection but take some getting used to.

The worst cases of dryness may require professional help and prescription treatments. For splits in the hands, cover with tape or a bandage which helps the pain and speeds healing. Soaking hands in warm water for 10 minutes puts some moisture back if a thick cream or ointment is applied immediately, followed by gloves. The same is true for the whole body: a plain water soak for 10 minutes followed immediately by greasy creams or ointments can help the driest skin. The secret is to not let the water evaporate before applying moisturizers. Apply the cream or ointment within 60 seconds. It takes a while to get used to the greasy feel but the improved moisture in the skin should be apparent within a few days.

Finally, two common misconceptions deserve mentioning:
1. Applying moisturizers does not shut down your skin’s ability to make its own oil. It is safe to use moisturizers as much as needed; the skin will not become dependent on them.
2. Moisturizers per se will not prevent aging of the skin unless they contain sunscreens.

HORMONAL ACNE IN WOMEN

by James Channing Shaw, MD

It is common for women to get acne in their 20s or 30s for the first time. The cause usually centers around hormonal issues.

A common scenario is the woman who gets acne within a year of stopping birth control pills. Women often take birth control pills for years in their teens or early 20s, and their acne is controlled. When they stop taking birth control pills, hormones return to having fluctuations that lead to acne.

Another cause comes from irregular ovarian activity that causes hormone fluctuations. These women often have irregular periods or acne that gets worse a week before each period. Any woman can have this problem, and at its worst, it is part of polycystic ovarian syndrome. There are other diseases that lead to hormonal acne, but fortunately they are rare.

The hormone that causes acne is the male hormone testosterone and its metabolites. Women produce testosterone in small quantities, but several conditions lead to increased testosterone effect. An increase in body weight, for example, shifts hormones toward more testosterone effect. Ovaries or adrenal glands can spontaneously overproduce male type hormones. Stress causes acne mainly through overproduction of hormones by adrenal glands.

This photograph shows a typical woman with moderately severe hormonal acne. Women with adult hormonal acne commonly have pre-menstrual worsening, and involvement of the lower face and jaw-line. Their acne is usually larger red pimples instead of blackheads on the forehead. Increased oiliness on the face is common. Some women have unwanted hair growth on the face. Irregular menstrual periods are common as well.

Standard topical acne treatments can be effective in women with adult acne, but most need hormonal treatments for optimal control. Even Accutane® is less effective in women with hormonal acne. The best treatments for adult women are birth control pills and spironolactone.

Birth control pills not only provide a steady state of hormones, they reduce overall testosterone effect through a protein called SHBG (sex hormone binding globulin). The net effect (in addition to not ovulating, i.e. prevention of pregnancy) is less stimulation of the oil glands and facial hair follicles. Many women can achieve complete control of their acne with birth control pills alone. Health risks from birth control pills are fortunately very low, but certain women have higher risks of blood clots, and full discussion with the prescribing doctor is essential. Brands of birth control pills differ by country, and some are marketed for acne.

Spironolactone is an oral drug that blocks the receptor for testosterone and prevents hormonal stimulation of acne. This drug is mainly used as a diuretic in older patients. The acne benefit was discovered as a side effect years ago. Spironolactone is well tolerated by itself, with a 40 year track record of safety in young women, but works best when given together with birth control pills. Side effects include menstrual irregularities when it is given alone.

This photograph is the patient above after a year of combination hormonal treatment. Her acne is much improved and the hair on her lip has reduced. Many women achieve excellent control within a few months with hormonal treatments, but ongoing treatment is necessary in most cases. It is important to find a doctor who is familiar with the use of these drugs for purposes of monitoring.

Finally, two recent developments in acne: 1) Cosmetics have been shown not to aggravate or cause acne in most cases. 2) Dietary influences of a western diet high in carbohydrates and dairy products may worsen acne through complex hormonal mechanisms, so a reduction in carbs and milk products may be beneficial.

HAIR LOSS (ALOPECIA)

                                      James Channing Shaw, MD

 Some of the most worried patients in a dermatologist’s practice are those who are losing their hair. The medical term for hair loss is ALOPECIA. The most common type of alopecia is male balding, but there are many conditions that lead to hair loss, some temporary, some permanent. In this post, I discuss only the most common causes.

Hair growth cycles. To understand hair loss, you have to understand hair growth cycles. 80% of hairs on the scalp are in active growth-phase (called Anagen phase), which lasts for years. When growth-phase is completed, the hair stops growing, the root becomes small and round, and the hair goes into a resting-phase (called Telogen phase). After about ninety days in resting-phase, the hair falls out, and a new hair root begins making a new hair. Only 20% of human hairs are in resting-phase at any one time. By comparison, some animals ‘shed’ seasonally because all hairs go into resting-phase at the same time.

Growth-phase (anagen) roots are the ones most vulnerable to illnesses or medications. The prime example is cancer chemotherapy. Chemotherapy destroys rapidly growing cancer cells and growth-phase hair roots get damaged as innocent bystanders.

Androgenetic alopecia. The most common form of hair loss is male pattern balding (medical term: ‘androgenetic alopecia’). It is a genetic response to the male hormone testosterone which men have in abundance and women have in small amounts. Androgenetic alopecia usually happens gradually with no noticeable shedding of hair, just a relentless thinning and shortening of existing hair until (in worst cases) there is complete balding of the top of a man’s scalp. Women with androgenetic alopecia usually do NOT go bald, just thin. The growth-phase hair roots become smaller and smaller over years until they are too small to make visible hair.




Androgenetic alopecia





Treatments for androgenetic alopecia. It is now known that the naturally modified form of testosterone called dihydrotestosterone (DHT) is the culprit of androgenetic balding. Without DHT, there is no balding whatsoever in men. (We know this from studying families that cannot make the DHT). Therefore, the drug finasteride (Propecia®) was designed as the first effective drug for male balding because it blocks the conversion of testosterone to DHT. Unfortunately, Propecia does not grow new hair, it merely slows the balding process. In post-menopausal women, sadly, it has very little positive effect.


Minoxidil (a blood pressure drug) was discovered to have the side effect of hair growth, so a topical product Rogaine® was developed which can be a helpful adjunct to treatment but rarely produces a full head of hair. Statistically, about one third of men see benefit after a year, slightly higher in women.


For women with androgenetic alopecia, hormonal treatments are the most effective, though limited. In young women, birth control pills plus antiandrogen drugs (spironolactone) are used together, along with Rogaine® topically. Occasionally Propecia® is added but no large studies have proven its effectiveness in women. In older women, hormone replacement therapy (HRT) plus spironolactone are most commonly used.

Telogen effluvium

Telogen effluvium. Shocks to the system cause hair to fall out by converting growth-phase hair to telogen (resting) hairs. A high fever or general anesthesia during surgery can trigger many hairs to stop growing. They don’t fall out right away but go into the resting phase for 60 to 90 days and then fall out. Pregnancy is another example. Many of us know women who delivered a baby, and three months later started losing their hair. Fortunately the hair usually grows back. This kind of resting-phase hair shedding is called ‘telogen effluvium’. Other stresses that cause telogen hair loss are surgery, blood loss, or any severe illness.

Chronic telogen effluvium. This is the diagnosis when increased shedding lasts for months. Thinning of total hair mass occurs in worst cases. In young adult women, low iron has long been thought to contribute by triggering growth-phase hairs to convert to resting-phase hairs, and if thirty or forty percent of hairs are constantly in resting-phase, shedding increases, in the shower drain, on brushes, on clothes. Since women lose blood every month with menstruation, and if iron intake is inadequate, healthy growth of hair may be impaired. The diagnosis requires a specific iron test called ferritin which indicates the total body iron stores. The ferritin level should be above 40 for adequate hair growth. Eating more red meat or taking iron supplements can reverse the problem. The iron theory has recently been challenged in new studies, and further investigations are needed.


Many drugs can trigger ongoing hair loss of the ‘chronic telogen’ type. Fortunately it is not permanent, but it is often difficult to identify the medication causing the problem when multiple medications are being given. Stopping or changing medications requires careful monitoring by a physician.

Other diagnoses:

Alopecia Areata

Alopecia Areata. AA, though not as common as the types described above, is a huge topic that goes beyond the scope of this posting. Briefly, it is immune-mediated (autoimmune) hair loss. It can be mild, occurring in localized areas of the scalp, or in the worst cases, it can affect every hair follicle on the body. Patients with AA should be screened for other autoimmune conditions such as diabetes, thyroid disease, and anemia. All treatments for AA are designed to turn off the immune destruction of growth-phase hair follicles. Treatments range from local injections of steroids all the way to internal immune-suppressing drugs. Results are frequently unpredictable.

Tinea Capitis (ringworm)

   Ringworm (medical term: tinea capitis). This is a fungal infection of the scalp, common in children. It is contagious through direct contact, combs and brushes. Any child with patches of hair loss should be seen by a skilled nurse or doctor to make the diagnosis and treat with anti-fungal drugs.



Lupus. A more severe and different autoimmune disease, Lupus erythematosus can affect hair, leading sometimes to permanent scarring hair loss. Treatments also range from injections to serious immune suppressants.

Natural approaches, vitamins, nutrients. Iron and protein are probably most important. Iron is discussed above. Modern western diets frequently do not have enough protein for healthy hair. While not studied scientifically, individuals should eat three portions of protein per day for optimal hair growth.

Too much vitamin A (greater than 25,000 IU/day) can cause hair loss. Biotin deficiency causes hair loss, and supplementation with Biotin can be beneficial in telogen type hair loss. Research has shown that ingredients in Chinese green tea block 5- reductase and could lessen androgenetic alopecia, although no large scale clinical studies have been done.

Finally, a word on commercial hair care products. There is no hair care product that penetrates deep enough to influence hair growth at the level of the roots. Most products are washed off and even those that remain on the scalp cannot penetrate deep enough to influence the roots. No matter what they claim about roots, hair care products can only affect the shape and texture of existing hair and the top layer of scalp skin. If too harsh, they cause breakage over time.