Perilous Pedicures

Having a pedicure can work wonders on your toes, but your shins may not fare as well. State health departments in California have been investigating numerous cases of an unusual bacterial skin infection that develops following salon pedicures. As of December 2004, Santa Clara County has reported nine confirmed cases, 34 probable cases, and 65 cases awaiting interview. These skin infections, called Mycobacterium furunculosis, are caused by a bacterium called Mycobacterium fortuitum.

In 2000, one of the largest outbreaks of Mycobacterium fortuitum took place in a California nail salon. In September of that year, a dermatologist in Northern California reported to the state health department that four of her patients had persistent boils on their legs below the knee. A common factor among the four was that they received pedicures from the same nail salon. Dr. Kevin L. Winthrop and his colleagues investigated the situation and performed the first case study on the outbreak of Mycobacterium fortuitum in a nail salon. They found that 110 customers had furunculosis, which caused boils on their shins. When the boils were tested for bacteria, 34 of the 110 were positive for Mycobacterium fortuitum. All clients had similar case histories. After receiving pedicures, small sores developed on their lower legs — and after several weeks or months, they became large, tender boils with some even progressing to skin ulcers. Additionally, each infected client had between one and 37 boils on each leg.

With all of this information, the next step was to determine the exact source of the outbreak. Through a series of tests on the boils testing positive for M. fortuitum, it was discovered that a single strain of M. fortuitumwas responsible for the infections. It was concluded that the bacterium was in the salon’s tap water and that it began growing in the accumulated debris of hair, skin, and nails behind the footbath inlet screens, which were rarely cleaned. The bacteria then multiplied rapidly due to the warm, nutrient-rich environment. The bacteria presumably gained access under the skin through tiny abrasions in the skin caused by clients shaving their legs with a razor before the pedicure.

Mycobacterium fortuitumis a bacterium found basically everywhere on earth, including soil and tap water. It is only a problem for humans when nutrient content and temperature are at the right levels, allowing the bacteria to multiply in large amounts. Most of the time it is not a problem when it comes in contact with the skin. M. fortuitumhas probably been around for a long time, but has only been known to cause harm to humans in the last few decades. The first record of a M. fortuituminfection in humans was in 1936 from an abscess that resulted from a vitamin injection.

Mycobacterium fortuitum is typically not spread from person to person. Usually humans acquire it from the environment when bacteria gain access through a break in the skin. Once humans have been infected with M. fortuitum, it can become harmful. The strength of one’s immune system also influences how susceptible a person is to developing an infection, and those with suppressed immune systems have a greater chance of developing infection. If M. fortuitumdoes cause a skin infection, treatment is available with antibiotics. At least two antibiotics are needed to treat M. fortuitum because drug resistance against a single antibiotic is common. The treatment can last as long as 6 months. If antibiotics do not solve the problem, surgical removal of affected areas may be necessary.

Infections associated with nail salons are under-recognized and may increase in prevalence because a large number of salons are deficient in their cleaning practices. There is no preventative method available to guarantee that one will not develop an infection caused by Mycobacterium fortuitum.However, there are measures one can take to decrease the likelihood of contracting this infection.

Judy Hagerty, RN, MS is a freelance writer.

References

1. Landhuis, Esther, “Sweep Targets Nail Salons”. San Jose Mercury News, January 6, 2005.

2. Public Health Update from County of Santa Clara Public Health Department. December 22, 2004.

3. Weeks, Kevin. (2001). “Don’t Overlook Safety in the Nail Salon.” Retrieved June 21, 2002 from http://www.hdlp.hr.state.or.us/pdf.

4. Winthrop, Kevin L., MD, Marcy Abrams, RN, Mitchell Yakrus, MS, MPH, Ira Schwartz, RN, MPH, Janet Ely, BA, Ducan Gillies, BA, and Duc J. Vugia, MD, MPH. May 2, 2002. “An Outbreak of Mycobacterial furunculosis associated with Footbaths at a Nail Salon.” The New England Journal of Medicine, 346: 1366, 1369, & 1370.

5. Woeltje, Keith F., MD, PhD. (January 9, 2002). Mycobacterium fortuitum. eMedicineJournal, 3. Retrieved June 21, 2002.