Shingles complications can include ongoing pain well after the rash has cleared.
Patients suffering from shingles, an outbreak of rash and blisters that are accompanied by a burning sensation, tingling pain, numbness and/or itching caused by the varicella-zoster virus (VZV), can experience shingles complications that range from annoying to debilitating. After a person has chickenpox, a common childhood illness, the VZV retreats to the nervous system where it stays unless is it reactivated in the form of shingles. The virus then gains access to the epidermal (skin) cells and causes what is called a varicella rash. The rash generally appears on the face or body, and its main symptom is pain. It usually lasts for 2 to 4 weeks. Fever, chills, upset stomach and headaches are other common symptoms.
Twenty percent of people with shingles continue to experience pain after their rash clears up. This condition is called post-herpetic neuralgia (PHN), and according to the Cleveland Clinic, it is caused by damage to nerve fibers during the shingles infection. The condition can last for months or even years, and it is difficult to treat. Older individuals may find the pain debilitating, and for many individuals regardless of age, the skin sensitivity is so great that patients cannot tolerate clothing touching their skin or even a breeze blowing on their skin. This agonizing pain can lead to a disruption of sleep, mood and work, and patients may feel a loss of independence as they cannot complete normal daily tasks. According to the Centers for Disease Control and Prevention, social withdrawal and depression are adverse affects of post-herpetic neuralgia.
Some sufferers of PHN use a lidocaine patch. Another treatment method is transcutaneous electrical nerve stimulation (TENS), which is a treatment where low-level electrical currents are applied to the skin. This causes a tingling sensation that relieves people's pain as the body releases endorphins, which is the body's natural way of killing pain.
A last resort treatment method is a nerve block, which can provide temporary relief. A doctor injects a local anesthetic at the point of the affected nerves to relieve the pain. Other noted medications include tricyclic topical analgesic agents, anticonvulsants, antidepressants as well as opioid analgesics.
According to the Mayo Clinic, people with weakened immune systems are more likely to develop shingles. The people in this category include those with HIV/AIDS, those receiving medical treatment such as chemotherapy or radiation or those with a history of bone or lymphatic cancer. When this group of people has a VZV reactivation, they may initially present typically, but the rash tends to be worse and it takes longer for the symptoms to disappear.
Persons with HIV that have a VZV reactivation have also shown atypical skin eruptions as well as aggressive acute retinal necrosis that can cause the patient to go blind. Bone necrosis and tooth exfoliation have also been reported.
Varicella rashes that appear on the face can lead to complications with hearing or vision. Eye involvement from shingles, called herpes zoster ophthalmicus (HZO), happens in 10 to 25 percent of cases. This happens when the nasociliary branch of the trigeminal (fifth cranial) nerve is involved in the shingles reactivation. Approximately two-thirds of the patients with HZO also have keratitis (inflammation of the cornea), which can also cause corneal ulceration. Other ocular symptoms include:
Ramsay Hunt syndrome, a peripheral facial nerve palsy, is an uncommon complication of shingles that happens when VZV reactivates in the geniculate ganglion (a collection of sensory neurons) of the facial nerve. Hearing loss, pain, vertigo and loss of taste are symptoms of this condition.
Bacterial skin infections can occur from improper care of open sores, which can lead to cutaneous scarring from the shingles rash. In rare circumstances, more serious conditions such as toxic shock syndrome and necrotizing fasciitis, an infection that destroys underlying soft tissue, can occur.
Bacterial skin infections can be avoided by good hygiene, including daily bathing as well as clean, well-trimmed finger nails.
Shingles can occasionally cause motor weakness called zoster paresis. This weakness generally develops two to three weeks after rash onset, and has also had diaphragmatic paralysis (paralysis of the diaphragm) described with it.
Acute focal neurologic deficit (a nerve problem that can affect functions such as speech, vision and fine motor skills) is another rare complication that can occur weeks to months after the original rash. A direct extension of VZV in the internal carotid artery or its branches can cause what is called a granulomatous angiitis, or an ischemic stroke syndrome.