A 54-year-old patient in otherwise excellent health recently appeared in my office. After suffering from terrible leg pain for two days, she noted the appearance of a rash. Although she did not connect the two, it was clear her diagnosis was herpes zoster, commonly known as shingles.
Shingles is caused by the same virus that produces chicken pox, varicella zoster. About 95 per cent of the population has had a case of chicken pox by the age of 18. After that exposure, the virus never leaves the body but remains dormant, asleep, in nerve cells that are at the base of the brain. Years later, although we are not sure what exactly triggers it, that virus can reactivate, travel down the spinal cord and crop up anywhere on the body.
In order to get shingles, you must have had a case of chicken pox. In some people, that case of chicken pox might have been so mild that it went undiagnosed.
Shingles is not caught from someone else suffering shingles. And you do not catch shingles if you are exposed to someone with chicken pox. However, a person who has never had chicken pox, can come down with chicken pox if they are exposed to the shingles rash.
It is estimated that one in seven people over the course of an 85-year life span may get shingles. Often, the early signs of shingles are not recognized as they can be non-specific. There can be a burning or itching pain, tingling or numbness on one side of the body. There can be flu-like symptoms such as headache, nausea or even fever.
The rash typically appears within two weeks of the onset of symptoms. It appears as a cluster of blister-like lesions that is typically on one side of the body in a band of skin (called a dermatome). The rash will usually heal in a few weeks.
Although shingles can occur anywhere on the body, common locations include the chest, back, abdominal wall, head, face and lower part of the neck. In rare cases, shingles can occur without a rash.
The risks of getting shingles increase in older patients, those with weakened immune systems, such as patients undergoing chemotherapy, radiation therapy, underlying chronic illness, HIV and, perhaps, even stress. In addition, a person can get shingles more than once. It is thought to recur in an estimated 1 to 5 per cent of patients who had a previous case of shingles.
Complications of shingles, particularly in those who are immunocompromised can include myelitis (weakness and incontinence) and infections of the central nervous system such as encephalitis with changes in speech, seizure and loss of movement in facial nerves. If shingles affects the eye, the cornea can become infected resulting in temporary or permanent loss of vision. It is possible to affect hearing as well.
The pain associated with shingles is often severe, debilitating and not easily controlled. In 36.6 per cent of patients with shingles who are older than 60 and 47.5 per cent of those over 70, the pain persists for more than a year. Pain that continues for one to three months, or even years after the rash has healed, is called post herpetic neuralgia (PHN).
PHN is a chronic pain state where often the nerve fibres might be damaged. Recommended treatments for PHN include tricyclic antidepressants, an antiepileptic drug called gabapentin, a lidocaine skin patch and painkillers called opiods.
The American Academy of Neurology stated that there is not enough data to make any recommendations on the long-term effects of these treatments. In their review, they did not find ASA and capsaicin cream, acupuncture or laser treatment to be useful in treating the pain.
If you suspect a diagnosis of shingles, it is critical to get to your physician. Within 24 to 72 hours after the appearance of the rash, the use of antiviral drugs such as acyclovir, famciclovir and valaciclovir will speed recovery.
They might also reduce PHN.
Recently, the U.S. Food and Drug Administration approved the use of a vaccine called Zostavax to prevent shingles. The vaccine is recommended for people 60 years of age and older who have had chicken pox but who have not had shingles. The vaccine has shown a reduction in the development of shingles by 51 per cent.
For those vaccine recipients that still went on to develop shingles, there was a 61 per cent decrease in the burden of pain and discomfort. The incidence of PHN was reduced by 66 per cent in the vaccine-administered group. The same as the vaccine given in childhood to prevent chicken pox, the shingles vaccine was found to be safe and effective. Common side effects included redness, pain or swelling at the vaccination site. Serious adverse events were reported at 1.9 per cent of vaccine recipients compared with 1.3 per cent of placebo recipients. It is not yet available in Canada.
With our aging population, shingles remains an increasing concern.
Dr. Marla Shapiro can be seen Tuesdays on CTV's Canada AM. Questions about general health issues can be sent to her at: firstname.lastname@example.org (Please direct queries about personal health issues to your doctor.)