Shingles

Shingles, also called herpes zoster, is a nerve infection caused by the varicella zoster virus. This is the same virus responsible for chickenpox. Anyone who has had chickenpox can develop shingles later in life. This viral infection causes a painful rash along a band of skin and tissues supplied by the affected nerve.

How long does shingles last?

The symptoms of shingles persists for 2-4 weeks, and the pain may persist after the rash has subsided.

Is shingles common?

Shingles is more common among individuals age 50 and older. Around 20% of people develop shingles at some point during their lives. The rash may occur at any age, but it usually affects older adults.

What causes shingles?

Chickenpox is not as common as it once was, since the childhood varicella vaccines was implemented in the 1990s. However, older people did have chickenpox during childhood, so they are at risk for shingles. The virus never leaves the body, but remains inactive in the nerve roots near the spinal cord. Most people have no problems or symptoms. However, the virus may reactivate years later.

For most people, shingles occurs for no reason, but for others, stress or illness triggers it. Aging of the immune system accounts for shingles flare-ups in older people. In addition, shingles is more common among people with a compromised immune system. Shingles also occurs in people who take steroids, those on chemotherapy, and individuals with HIV or AIDS.

What symptoms are associated with shingles?

The shingles virus affects only one nerve, and most always flares up on one side of the body (unilateral). Symptoms of shingles include pain, rash, itching, and irritation of the skin. The most common site for shingles is the chest. The abdomen and upper face are also commonly affected.

The pain of shingles occurs along a band of skin/tissue. Depending on the affected nerve and body region, the pain can range from mild to severe. Most people describe the pain as burning, dull, and gnawing. In addition, many patients report stabbing, sharp pain that comes and goes. When the rash resolves, the skin is often left feeling tender and sore.

The pain is present for 2-5 days before the rash occurs. Red blotches appear and develop into itchy blisters. The rash resembles that of chickenpox, and only appears on the skin of the affected nerve. New blisters may appear after a week. In addition, the tissue around and under the rash often becomes swollen from inflammation, which is related to the virus. When the blisters dry, scabs form, and then the rash gradually fades away. Some patients are left with slight scarring where the rash/blisters were.

Is shingles contagious?

You cannot get shingles form a person who has shingles, but chickenpox is contagious. The shingles rash is contagious when the blisters are open, but it will only pass the chickenpox virus to someone who has never had the disease. The blisters are covered with a dressing, so the virus is not likely to be a problem. There is no threat of catching chickenpox as long as an individual does not touch open sores on the patient.

What are the complications of shingles?

Around 25% of people who have shingles go on to develop post-herpetic neuralgia (PHN). This condition is not common for people under age 50 years. PHN causes persistent pain, even after the shingles rash has resolved. PHN can cause chest wall pain, eye pain, or abdominal pain that becomes chronic.

How is shingles treated?

The person is advised to wear loose-fitting, cotton clothing, which does not irritate the skin. Pain can be relieved with ice packs, a cool bath, or wet dressings. Additional treatment options include:

  • Pain medicines – These include Paracetamol with codeine, anti-inflammatory agents, tramadol, hydrocodone, and oxycodone.
  • Antiviral medicines – These include famciclovir, acyclovir, and valaciclovir. These drugs work to destroy the virus and keep it from multiplying. It is best for the patient to start an antiviral agent as soon as the rash of shingles appears, as this prevents development of PHN.
  • Other medicines – Tricyclic antidepressants work by changing the brains perception of pain. Anticonvulsants also are used to treat shingles, which works by altering nerve impulses.
  • Selective nerve root block – The affected nerve root that branches off the spinal cord sends the painful signals to the brain. The doctor can inject this nerve with an anesthetic, corticosteroid, and/or neurolytic agent to interfere with the pain signal transmission. A selective nerve root block is done using x-ray guidance to assure correct placement of the needle. This procedure has an 87% success rate, according to a recent research study.

Resource

Narouze SN, Vydyanathan A, Kapural L, et al. Ultrasound-guided cervical selective nerve root block: A fluoroscopy-controlled feasibility study. Reg Anesth Pain Med. 2009;34(4):343-348.