Dangers of a fungal nail

Conway McLean, DPM

A foot and ankle physician is called upon to treat a host of serious and consequential problems. A broken heel bone has far-reaching manifestations not readily apparent to the casual observer. A diabetic with an open sore is at risk for a bone infection, with amputation a common consequence. Various deformities of the toes and feet can result in a lifetime of pain. Vein problems can lead to chronic open, draining wounds on the lower legs that carry with them a profound social stigma. These are some of the conditions experienced on a daily basis.

Yet the general perception of what kind of conditions a podiatric physician treats is quite different. In contrast to some of the serious maladies encountered, many imagine that a podiatrist spends his day trimming calluses, clipping toe nails, and padding shoes. There is a sliver of truth to this; nail problems are certainly ones that we commonly treat. A host of different nail problems present to our offices, including ingrown nails and injuries to the nail. But the winner, from a statistical standpoint, is that of the fungal nail.

Everyone has heard of this problematic nail condition. Images of nails affected by this type of infection are easy to find. Thickened and misshapen, with a variety of colors produced, nail fungus is a slowly developing, but inexorable process. It can take years for a nail to become grossly infected with a fungus. One of the problems is that, by the time it becomes obvious, the invading organism has become well-entrenched, and thus extremely difficult to eradicate.

Fungal nails tend to exhibit certain predictable changes. Along with the color changes just mentioned, one of the most noticeable are alterations in the shape. The nail plate will often go from the normal, flattened configuration to one of extreme curvature. Alternatively, the nail may become thick and club-like, growing straight up. Additionally, infected material will gradually build up under the nail, lifting it slowly off the toe. Because of this peculiarity, fungal nails are often very poorly attached.

One of the most common questions about nail fungus (technically termed onychomycosis) concerns possible health hazards. It’s just a cosmetic problem, right? Unfortunately, this is not the case, and a variety of complications can occur. A lot depends on your general health status. Individuals with poor blood flow, for example, like many elderly, are more susceptible to onychomycosis. Often the nails will become thickened and discolored because of inadequate blood flow, without any fungus present. Treating a nail fungus when there is no actual infection would obviously be a mistake. A thorough, detailed exam is critical to a proper diagnosis, even for nail fungus.

Perhaps the most common complication of onychomycosis is a painful ingrown nail. These nails can become so curved that the sides of the nail can meet in the middle, like a horseshoe that is bent even further. But because this is a gradual process, and not a sudden development, the skin adapts to these changes, and significant pain may not be experienced (although it looks like the nail should really hurt!). Sometimes the worst complication is the damage wrought when the afflicted individual tries to cut these distorted, misshapen nails.

What happens when someone with diabetes develops a fungal nail infection? These are individuals that have an impaired immune system, one of the more predictable conditions associated with this extraordinarily common disease. Because of this impairment, any opening in the skin of someone with diabetes can (and has) lead to a limb-threatening infection. These nails, poorly attached as they are, will often separate slightly from the toe, causing a small erosion under the nail. Obviously, this opening is hidden by the nail plate, and is thus unseen.

The American Diabetes Association, as well as most experts, recommend that people with diabetes treat their fungus nails. A ‘simple’ fungal nail infection can allow a secondary bacterial infection to get started. The nail unit is a great place for various microorganisms to hang out. And because the root of the nail sits right on top of the toe bone, a bone infection can develop, which the diabetic often won’t feel because of the nerve changes that usually accompany diabetes.

There are a variety of different fungal organisms that can cause onychomycosis. Many of these can also cause a fungal skin infection (aka athlete’s foot). If a fungal skin infection is allowed to develop, tiny cracks in the skin can result, which, again, can lead to a bacterial infection like cellulitis. If the sufferer has diabetes, or an impaired immune system as a result of some other kind of medical condition, the product may be a serious, limb-threatening infection. When someone has reduced blood flow to the feet, the body may not be able to fight the infection, as well as whatever damage may occur.

Typically, it is impossible for the trained professional to definitively diagnose a fungal infection by visual appearance alone. The only certain way is by sending a biopsy specimen to a specialized lab, one that utilizes the services of a physician trained to diagnose skin problems from the analysis of tissues (known as a dermato-pathologist). These specialists are not “a dime a dozen”, yet their services are essential.

Once a specific diagnosis is made, a discussion about treatment options should follow. This where it gets interesting, since there are so many choices, each with its own rate of success and possible side effects. Unfortunately, the simplest method, a topical medication, rarely results in a clean, normal nail unless the problem is caught extremely early in the process. With the use of a topical medicine alone, typically one is realistically looking to slow progression of the disease. This is partially due to the fact the nail provides such an excellent barrier to the skin fungus medicine.

Most everyone has heard of the oral medication, terbinafine (trade name: Lamisil), which has a much better success rate than topical alone. Unfortunately, it has the potential to cause liver changes, which are not always reversible. Although rare, the very possibility that permanent damage to one’s liver may occur causes many to forego this option. A new dosing regimen has significantly reduced the odds of this, but many still shy away.

Various surgical options exist. Thorough trimming and thinning of the nail, considered surgery by the insurance industry (?!?), is important, and noticeably improves the success rate of any medicinal treatment. Permanent removal of the nail clearly resolves the problem, and can be achieved with minimal discomfort by using a radio wave surgical device. No nail means no nail fungus!

A new technique for the treatment of nail fungus has been used for various strange skin conditions for decades. Photo-dynamic therapy has a long track record of use for various dermatologic conditions, but has only recently been used for onychomycosis. All the rage in Europe for treating this resistant malady, it is only now making its way to the states. Yet, because there are no side effects, little work is required of the patient, and the success rate is better than any previous method, it looks to be the next rage in nail fungus treatment.

If there is one caveat to be provided here, it is that early treatment is ALWAYS more successful. And don’t depend on one method. The more “weapons” brought to bear, the better the success rate. Don’t ignore that discolored toe nail: you may be consigning yourself to a lifetime of disfigured, horrific, painful toe nails. Get it checked out since time is of the essence.

Editor’s note: Dr. Conway McLean is a podiatric physician now practicing foot and ankle medicine in the Upper Peninsula, having assumed the practice of Dr. Ken Tabor. McLean has lectured internationally on surgery and wound care, and is board certified in both, with a sub-specialty in foot orthotic therapy. Dr. McLean welcomes questions, comments and suggestions at drcmclean@penmed.com.