Mayo Clinic Researchers Discuss Local Case Studies on Leprosy

Leprosy has a history that spans centuries and societies around the world. Yet this continues to be a problem even in the modern era. People with this chronic and infectious skin disease still face social stigma and lack of medical care since the onset of the disease. Although leprosy can be treated, the World Health Organization reported 216,108 cases in 2016, with some of these patients seeking treatment on the campus of the Mayo Clinic in Rochester.

By examining risk factors and demographic information on victims, researchers are examining local leprosy case studies in the next issue of Mayo Clinic Acts.

Using a database of electronic health records, the researchers identified nine leprosy patients who were badessed and treated at the Mayo Clinic from 1994 to 2017. Demographic information was obtained on these patients, including their age, bad, country of origin, travel history and results of a skin biopsy. Seven patients were men and two were women. Their ages ranged from 15 to 63 years old. Six patients had emigrated from foreign countries – Guam, Indonesia, Mexico and Micronesia – and three patients were born in the United States. All patients had skin lesions due to leprosy, affecting the trunk, lower limbs, and / or head and neck. Many patients also had neurological symptoms, including decreased sense of touch.

Common factors observed in the patients' badysis include the Micronesian lineage and many trips while being immunocompromised. Spencer Bezalel, M.D., one of the authors, notes that the average person in the United States is not at risk of contracting leprosy. "Immunocompromised people who travel to countries where the disease is prevalent are the most at risk, as are people who plan to stay in close contact with other people for long periods of time," says Dr. Bezalel.

Leprosy is caused mainly by the bacteria Mycobacterium leprae. Sometimes it is caused by a newer species called M. lepromatosis. The disease mainly affects the skin and peripheral nerves. Although the exact mechanism of transmission is not known, it is believed that a person must be in contact with an infected person for an extended period of time. In some cases, armadillos, hosts of the bacteria, are known to transmit the disease. In most modern cases, people who contract leprosy are immunocompromised, such as transplant patients or those taking immunosuppressive drugs for other reasons. Otherwise, these people live or travel to places where the leprosy rate is high.

Although leprosy is rare in the United States, this study shows that the disease can not be totally excluded under certain circumstances. Treatment of leprosy with antibiotics and vigilance on the part of immunocompromised persons or those traveling considerably are sufficient to prevent the ravages of leprosy in the past. "Leprosy is not very contagious and does not spread easily, and most people are immune to the disease," said Dr. Bezalel.