Text for the Quebec Association of Dermatologists website, Nov. 26, 2006. Yves Poulin
HERPES ZOSTER (Shingles)
Case history and description
Today is a Sunday. 3 days ago, Mrs. Tremblay, 75, felt a tingling and pain in her forehead and scalp, both on the right side. This morning, she noticed some redness above the right eyebrow and on the right side of her nose. This afternoon, little cold sore-like blisters appeared, accompanied by redness. A case similar to Mrs. Tremblay’s can be found at the following website address: http://www.aafp.org/afp/20021101/1723.html. The pain became worse. She was now remembering a story her sister told her about the excruciating pain of shingles.
This is a typical onset of herpes zoster.
The cutaneous eruption is due to the same virus that causes varicella (chickenpox) in children. Mrs. Tremblay already carried the virus, having had varicella as a child, and it was now being reactivated.
The virus causes sudden irritation of a nerve (neuralgia, neuritis) and skin lesions. At first, red spots appear. These red spots are soon topped by tiny water-filled bumps (vesicles), all clustered in the same area and on the same side of the body. The eruption occurs in a specific area known as a dermatome. The following websites, which can be consulted for reference purposes, illustrate all the body’s dermatomes: http://en.wikipedia.org/wiki/Dermatomic_area and http://www.clinicalexam.com/pda/n_ref_dermatomes.htm
It is rare to see several dermatomes affected by shingles in a normal individual. Shingles cause pain (neuralgia). This neuralgia is often minor or negligible in young people, but the older the person, the more severe the symptoms.
Skin lesions usually heal in about three weeks, often leaving small scars or whitish (discoloured) skin patches where the eruption occurred. Topical treatment can avoid bacterial contamination that could delay healing.
There are two areas where shingles can cause significant damage: around the eye, and in the ear. Ocular shingles can significantly affect eyesight. Shingles affecting the ear can cause paralysis of the face and hearing disorders.
The main problem associated with shingles is chronic pain (persisting neuralgia) in the affected dermatome. The frequency of such long-term neuralgia increases with age. It is rare before the age of 50 but common past the age of 70.
The neuralgia can be felt and described in various ways: feeling of being stabbed with knives or needles, extreme sensitivity of the skin to any friction in the affected dermatome, tingling, feeling of hot coals on the skin. The pain can even prevent sleep; its effect in everyday life can be devastating. Even wearing clothes can become unbearable.
Fortunately, the intensity of this neuralgic pain is short-lived. However, it can last quite some time in the elderly, and it can make life hell for older people.
Shingles is not always easy to diagnose. The skin lesions may not be typical in every case. Furthermore, symptoms can be vague at first.
In individuals over the age of 50, antiviral treatment must be initiated as early as possible, to reduce the duration of the shingles episode and the risk of protracted and painful neuralgia.
In the near future, a vaccine will be used to prevent the appearance of shingles or reduce the intensity and duration of the neuralgia.
Mrs. Tremblay went to see her doctor on Monday. He prescribed antiviral tablets right away. Ideally, this antiviral treatment should be initiated within 72 hours following the start of skin redness, but it is still indicated for prescription whenever the onset dates back a week or less, in some situations (e.g. very painful shingles, facial shingles). Mrs. Tremblay was in a great deal of pain, so her doctor also prescribed a painkiller. Controlling the pain right from the start can reduce the chances that it will persist over long periods.
Since Mrs. Tremblay’s shingles was near her right eye, she was urgently referred to an ophthalmologist, as there is a high risk of damage to the cornea or eyeball when the nose area is affected.
SHINGLES
Data sheet
A common virus responsible for both chickenpox and shingles: Varicella-Zoster Virus (VZV).
VZV lodges in the nervous system of children who contract chickenpox. It remains dormant until reactivated later in life, sometimes without apparent reason, or due to a compromised immune system. The reactivation frequency of the virus increases dramatically with age. An 85year-old person has a 50% chance of developing an episode of shingles. A person has a 28% chance of having shingles in his or her lifetime. One per cent of subjects who have had shingles will have a second episode, and half of these episodes will affect the same dermatome.
Incubation
None. The virus remains dormant in the nervous system after a child’s bout of chickenpox.
Contagiousness
The virus causing shingles can infect a person who has never had chickenpox or has never been vaccinated against it. Such a person can contract chickenpox (but never shingles, which is a reactivation of the dormant virus). Chickenpox transmission can occur through contact with lesions but the virus can also be found in the air surrounding the infected person, making transmission through ambient air a possibility.
Symptoms prior to the appearance of skin lesions
There may be no symptoms before the onset of skin lesions.
Most of the time, there are precursor symptoms: burning sensation, tingling, shooting pain in a specific area. These symptoms start anywhere from 1 to 10 days prior to the skin lesions. The longer the duration of the symptoms before the appearance of lesions, the greater the risk of experiencing pain that persists after the episode of shingles. Other occasional symptoms include flu-like symptoms, with tiredness and, at times, aslight fever.
Skin lesions
They form in a specific dermatome, on a single side of the body. First, there is redness (red spots and papules). These red spots soon become swollen and form water-filled blisters that are similar to an outbreak of chickenpox or cold sores (herpes simplex). The lesions remain in the area where the pain is located.
A few isolated lesions may appear elsewhere on the body.
Duration
Skin lesions can last up to three or four weeks. This can be shortened if the condition is treated rapidly with oral antiviral drugs.
The duration of the accompanying pain varies, from negligible in young people to long and painful in older patients. The older the person, the more disabling and longer lasting the pain. As a general rule, the risk of persisting pain is proportional to the severity and duration of the precursor symptoms.
Complications
Numerous complications may occur.
Complications are rare in healthy subjects under the age of 50.
The most frequent complication is chronic pain in the dermatome (post-shingles neuralgia). Left untreated, this persisting pain occurs in more than half the cases of shingles in people who are 50years old or over, and in more than 70% of patients aged 80 or over.
Special complications should be guarded against in certain specific cases:
Shingles of the ophthalmic branch of the trigeminal nerve (skin lesions on the forehead, nose and eyelid). The eye may be affected, with potential loss of sight.
Ear shingles. There is a risk of reduced hearing or hearing loss, as well as a risk of facial paralysis, and other complications. This complex condition is known as the Ramsay Hunt syndrome.
Treatment
In healthy people under the age of 50, antiviral treatment specific to shingles is necessary only in special circumstances such as facial shingles or if the pain is severe.
Treatment of an acute episode basically consists in a 7-day course of oral antiviral medication available on prescription.
Treatment must be initiated within 72 hours of the onset of skin lesions.
Under special circumstances, it may be useful to take an antiviral drug for longer than 7days following the onset of skin lesions.
Topical care (mild antiseptic wash, compresses) of the lesions focuses on preventing bacterial contamination.
Pain control may include antidepressants or agents that can alleviate the pain, such as analgesics (painkillers). Ideally, the pain should be brought under control as early as possible.
Prevention
A vaccine, which should be available in the near future, has proven effective in preventing shingles and reducing the duration and intensity of the pain caused by shingles.
YP/yp French: November 29, 2006. English : February 18,2007.