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Ottawa, ON— Dirty acupuncture needles may have been the source
of a Mycobacterium abscessus outbreak in Toronto.
“The case series began when a 50-year-old presented to us at
the Sunnybrook dermatology clinic with a six-week history of multiple
weeping nodules over the legs and arms near previous acupuncture
sites,” said Scott Walsh, MD, a resident in the department
of dermatology, Sunnybrook & Women’s Health Science Centre.
Within a short time, six other patients with similar symptoms presented
to six dermatologists’ offices.Biopsies were obtained and sent
to Dalal Assaad, MD, pathologist at Sunnybrook. Although histochemical
staining techniques could not identify the infectious etiology in
these patients, Dr. Assaad noted similar suppurative and granulomatous
patterns. She and dermatologist, Christian Murray, MD, discovered
the link between their patients: the seven patients had all recently
visited the same acupuncturist.The Toronto Public Health department
was notified and M. abscessus was positively identified. Culture,
polymerase chain reaction, and genetic fingerprinting were used
to link the cases. However, the acupuncturist could not be conclusively
identified as the source of the infection.
“We were not able to test the materials, because just prior
to Public Health coming around many of the instruments and cleaning
solutions had been thrown out,” Dr. Walsh said at the
annual meeting of the Canadian Dermatology Association.
Mycobacterium cultures are ubiquitous. They are in soil, dust, and
tap water because they are resistant to chlorine. “They are
one of the most resistant groups of bacteria that we have,”
Dr. Walsh said. Cultures can grow briefly in 75 per cent alcohol.
There have been many outbreaks associated with self-cleaning endoscopy
equipment and dialysis catheters.
Infections can cause fatal pulmonary lung disease. People with chest
conditions (cystic fibrosis, emphysema, silicosis, rheumatoid arthritis,
esophageal achalasia, ankylosing spondylitis, body habitus [ie,
thin, pectus excavatum], and other mycobacterial conditions) may
be predisposed to pulmonary infection, according to the Infectious
Diseases Society of America. Immunocompromised people may be more
susceptible to Mycobacterium infection. All patients in the Toronto
outbreak were immunocompetent and HIV- and hepatitis-negative at
the three-month mark, said Dr. Walsh.
While the incubation
period is usually 30 days, Dr. Walsh and colleagues reported a 20-day
to six-month incubation period in this outbreak. In the literature
it varies from ten days to one year.
“Current
treatment guidelines from the Infectious Diseases Society of America
say that if there is a localized infection, clarithromycin plus
or minus surgical debridement is the way to go,” he said. “If
it is an immunocompromised disseminated case, dual or triple therapy
is required for the first two or three weeks, because there has
been about a 2.5 per cent resistance to clarithromycin in this population.”
Some patients who had been on clarithromycin for three or four months
were still getting new lesions that would spread. “We had patients
on eight months of clarithromycin, and many of them were just beginning
to resolve at this point.”
Dr. Walsh and
colleagues have identified between 150 and 270
people who have been exposed to M. abscessus in this outbreak. Of
these, 54 are suspect and 29 are probable.
The clinic is closed, and there is a class action lawsuit against
the acupuncturist.
Despite contracting
an infectious disease from acupuncture needles, some of these patients
still prefer alternative to Western health care, Dr. Walsh said.
“When they came in to [the clinic] it was very interesting
to hear some of them saying, ‘Well I don’t want medical
treatment for this, I want an alternative therapy.’”
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