Overview and Facts
Shingles are another expression of varicella-zoster, the virus responsible for chicken pox. Only people who have had chicken pox in the past can develop shingles. The virus remains in the body permanently, going dormant after visible signs of chicken pox disappear. Months or even years later, the virus emerges again, this time causing a distinctive mass of raised blisters. These fluid-filled sacs appear after days or weeks of unusual sensations in the skin on one side of the body or face. People with shingles describe the feeling as itching, burning or tingling. Numbness around the edges of the affected area is also common.
Because the varicella virus remains dormant in the nervous system and affects the nerve endings, shingles directly activates pain sensors. The discomfort associated with shingles varies from mild itching and burning to debilitating pain. In severe cases, people with shingles cannot tolerate wearing clothing or moving normally during the worst of the outbreak.
The condition is not contagious as shingles, but people who have never had chicken pox may develop chicken pox from contact with active shingles blisters, putting them at risk of developing shingles years or decades later. People with compromised immune systems are more likely to develop shingles.
Signs and Symptoms
The initial symptoms of shingles may manifest themselves as flu-like complaints. Headaches, sensitivity to light and aching joints occur in many people; a smaller number also develop gastrointestinal symptoms such as diarrhea and stomach upset. Lymph nodes may swell and become painful to the touch. This phase is called the prodromal stage.
Within 4 to 10 days, people with shingles develop a characteristic band of numbness, itching, burning or sensitivity to touch along one side of the trunk or face. The affected zone typically has clearly delineated edges even before lesions become visible. Patients describe normal reactions to touch within fractions of an inch outside the borders of the affected area. The skin within this band breaks into blisters and a burning or itching rash. The fluid in the blisters is initially clear, but turns cloudy within a few days. When the blisters burst, they form scabs that may feel intensely itchy. People in this active phase of shingles can pass the virus to those who have never had chicken pox.
After the active stage ends, approximately 15 percent of shingles patients are left with postherpetic neuralgia, or PHN. The effects of the virus on nerve endings may cause sensations of sharp or burning pain that last for months or years.
Causes and Diagnosis
It is unknown why the virus responsible for chicken pox becomes active again after years or even decades of dormancy. Common precipitating factors include:
- A weakened immune system
- Cancer treatment
- Immunosuppressants following transplant surgery
Diagnosis begins with a thorough patient history. Patients who have never had chicken pox cannot develop shingles, so a patient history can eliminate or confirm a diagnosis of shingles. Older people and those with immunological deficiencies are at greater risk; for these patients, flu-like symptoms put shingles on the list of possible diagnoses.
The painful rash of blisters on one side of the trunk or face is typically the definitive factor in diagnosing shingles. In serious cases affecting the face, the rash may also affect a patient’s eyes, threatening the person’s sight. This condition needs prompt treatment with antiviral medications.
Tests and Treatment Options
A doctor can order testing on the fluid within the blisters for the varicella-zoster virus to make a conclusive diagnosis in ambiguous cases. In most cases, testing is not necessary to determine the cause or progression of the disease.
Most treatments for shingles include easing the pain of the condition with over-the-counter anti-inflammatory medications. Antiviral medicines may also reduce the severity and length of the outbreak. Topical numbing creams may reduce the pain of an active rash, while a course of steroid-based anti-inflammatory medications can lessen the active phase of shingles. People with postherpetic neuralgia are at risk of developing depression related to the disorder; antidepressants often help these patients. Anticonvulsants can also calm damaged nerve endings and ease the pain of PSN.
Helpful Tips and Home Remedies
Home care for shingles focuses largely on reducing discomfort from flu-like symptoms and skin rashes. Cool baths and compresses may ease the pain of blistered skin. Secondary infections can set in when blisters burst from scratching, so patients should refrain from satisfying the urge to scratch the itch. Keeping open skin from burst blisters clean helps prevent scarring.
It is imperative to see a doctor for any shingles rash that affects the eyes or for PSN.