I. What is shingles?
In recent years, the number of people suffering from shingles has been increasing. Herpes zoster is an acute infection that often involves the dorsal root ganglion and the skin innervated by it. (Both herpeszoster and shingles are called herpes zoster, the former from the Greek meaning “crawling girdle” and the latter from the Latin meaning “belt, girdle”).
What are the causes of shingles?
Herpes zoster is caused by varicella virus infection. After recovery from childhood varicella infection, the virus is latent in satellite cells of the dorsal root ganglion and is reactivated when the host immune function is reduced, such as by cold, old age, malignancy, HIV infection, and use of immunosuppressive drugs. Activated proto-dormant viruses can cause a very intense necro-inflammatory response in the dorsal root ganglia and dorsal horn of the spinal cord. In turn, the virus spreads retrogradely along sensory nerve fibers to the skin, causing severe skin pain and blistering, with a distribution of skin areas consistent with the infected peripheral and central nerves.
Third, the clinical manifestations of herpes zoster?
The clinical manifestations are generally severe neuralgia, segmental blistering rash, rash mostly distributed along a peripheral nerve, arranged in a band, and the preferred site is the intercostal nerve. However, special types of herpes zoster should be noted: herpes zoster of the eye, herpes zoster of the ear, herpes zoster meningoencephalitis, herpes zoster of the viscera, etc. These special types of herpes zoster can be serious, and some can lead to blindness, deafness, or even death. Some cases can be misdiagnosed as angina pectoris, biliary or renal colic due to early pain only, so clinical caution should be exercised.
What is postherpetic neuralgia (PHN)?
Postherpetic neuralgia is defined as pain that persists for more than one month after the clinical cure of acute herpes zoster. Postherpetic neuralgia is one of the most persistent pain disorders in the middle-aged and elderly population and is still a world-class pain problem. The duration of pain can be as short as 1 to 2 years or as long as 10 years, with a general history of 3 to 5 years. Patients suffer from chronic pain. Patients suffer from heavy psychological burden, depression, sleep disorders, poor quality of life, reduced ability to work and socialize, and even loss of confidence in life. The incidence of postherpetic neuralgia is proportional to the increase in age, according to relevant data: 49% for 50-59 years old, 65% for 60-69 years old, and 74% for 70-79 years old. The incidence of postherpetic neuralgia will continue to increase as the elderly population in China is increasing.
V. What are the clinical manifestations of postherpetic neuralgia (PHN)?
Usually, patients with PHN complain of three types of pain: persistent burning pain, paroxysmal irritation pain, pins and needles pain, and also complaints of tactile nociceptive abnormalities. 80-90% of patients present with nociceptive abnormalities that are dynamic in nature, such as pain induced by motor stimulation. For this reason, many patients experience severe pain when they wear clothing and rub their skin. Nurmikko et al. demonstrated that the affected segment has altered skin sensations of warmth, cold, thermal pain, touch, pins and needles, vibration and two-point position discrimination compared to the normal contralateral side. In addition to sensory deficits and pain abnormalities, the skin is usually pigmented and crusted. Due to the intensity and persistence of pain, PHN patients often suffer from insomnia, anxiety, emotional depression and even suicidal tendencies.
What are the views of Chinese medicine on herpes zoster?
Chinese medicine’s understanding of the etiology of acute herpes zoster: the cause of acute herpes zoster is external poisonous evil (virus), the evil qi stays in the body, wrestling with qi and blood, blocking the meridians, stagnating in the internal organs, so that the qi flow is blocked, the meridians are blocked, and pain occurs. The internal cause is internal injury, liver stagnation and fire or spleen and dampness, resulting in poisonous fire and liver fire, damp heat, and mutual wrestling, blocking the meridians, resulting in blood stasis and qi stagnation, not through the hair pain.
Acute herpes zoster, such as the Ming Dynasty’s book “Ulcerology Selections”, published in 1628, is known as “fire dan”, “fire belt sore”, “snake string sore”, etc., and has treatment prescriptions The book was published in 1628, and was called “fire pills on the waist”, “fire sores on the belt” and “snake sores”, and had prescriptions for treatment. However, there was a lack of in-depth understanding of herpes zoster in the early days, and it was not until the latter part of the 19th century that the medical profession knew that it was a viral disease.
Treatment of herpes zoster and PHN
1, antiviral drugs: treatment with intravenous acyclovir in patients with severely impaired immune function can reduce the risk of complications. However, acyclovir is not effective for chronic PHN. Therefore, it is not suitable for patients with diagnosed PHN.
2. Steroids: Steroids do not prevent PHN, although they do improve pain in the acute phase, and one needs to question whether it is cost effective to obtain their very limited efficacy with the increased side effects of steroids. Once a diagnosis of PHN is made, steroids do not have an analgesic effect.
3. Skin surface drugs
Many skin surface medications have been used successfully for acute herpes zoster and PHN. these include iodoside solutions, vincristine iontophoresis solutions, acyclovir ointment, capsaicin ointment, powdered aspirin with chloroform or ether as the solvent, EMLA ointment, benzamine (eucalyptus) ointment, and chloroethane spray. Recently, lidocaine patches have shown to be effective in relieving pain abnormalities in PHN and are now widely used in the United States.
4.Anticonvulsants
Anticonvulsants have been successfully used for the treatment of PHN. they seem to be the most effective drugs for the treatment of PHN pins and needles pain. Carbamazepine is the most widely used. Recent data suggest that gabapentin can control neurogenic pain, including PHN, quite effectively with minimal side effects.
5.Sleeping drugs
Phenothiazines and benzodiazepines cannot effectively treat PHN by themselves, but they can be used synergistically with tricyclics and analgesics because of their anxiolytic and antiemetic effects.
6.Psychotherapy
PHN pain is widely reported in the literature, depression becomes a distinctive feature of PHN patients, and patients are often suicidal. Therefore, if necessary, psychological counseling and long-term psychotherapy should form part of the whole treatment process of PHN.
7.Nerve block
Commonly used for herpes zoster pain, this method can focus the drug to the affected ganglion and sensory nerve fibers, this method is called nerve block method.
Eight, nerve block
The principle of nerve block method is to inject drugs with antagonistic effects on pain-causing neurotransmitters and eliminating inflammatory reactions of ganglia and sensory nerve fibers into the affected ganglia and sensory nerve fibers, so that such drugs act directly on the affected ganglia and sensory nerve fibers, resulting in high concentration of drugs at the affected area, fast and strong effects, and also blocking nerve conduction pathways, thus producing obvious pain-relieving effects. On the other hand, it promotes the regeneration of nerve cells and accelerates the repair of damaged ganglia and sensory nerve fibers, so the nerve block method is the main method of treating herpes zoster. Nerve block method is further divided into two kinds, one is called intercostal nerve block method and the other is called nerve root block method.
Nine, the current treatment methods
The current treatment of herpes zoster can be divided into two methods: outpatient treatment and inpatient treatment.
1, outpatient treatment of nerve block method is subdivided into two, one is called intercostal nerve block method, and the other is called nerve root block method.
The intercostal nerve block method is to inject the relevant drugs one by one into the intercostal nerve involved in herpes zoster, once a week, four times for a course of treatment.
The nerve root block method involves injecting the drug into the nerve ganglion involved in herpes zoster one by one, also once a week, four times a week.
The intercostal nerve block method is less effective in relieving pain than the nerve root block method because the area blocked by the nerve is not as large as the nerve root block method and the concentration of the drug in the affected area is not as high as the nerve root block method. While using anti-herpes virus drugs, intercostal nerve block combined with nerve root block can be used for those with severe disease and severe neuralgia. Based on the early use of antiviral drugs and other comprehensive treatment, nerve block therapy is an effective method to cure early herpes zoster and also an effective method to prevent PHN.
2. For some patients who are persistent and have poor results in outpatient treatment, inpatient treatment is available
First, continuous epidural block with epidural tube is placed at the lesion site for 1 to 3 weeks to provide analgesia, anti-inflammatory and dehydration treatment for the nerves at the lesion site. Then perform nerve disruption at the lesion site.
X. Health behavior guidance
1. According to the distribution of herpes zoster on one side of the body, let the patient lie on the healthy side to avoid local pressure and reduce pain. If the lesion involves the trigeminal nerve of the head and face, the eye should be well protected and cared for;
2.Create a quiet recuperation environment, reduce noise, room temperature should not be too high, light should not be too strong, in order to reduce stimulation;
3, try to eliminate pain factors, sleepless night, often extreme fatigue, resulting in a decrease in pain tolerance, increased pain, nursing staff should take the initiative to care, to ensure that patients rest and sleep, the appropriate use of analgesics, sedatives, fatigue eliminated, can improve the tolerance of pain;
4.Nurses should fully understand, sympathize and comfort the patient, avoid stimulating the patient in terms of language and behavior, treat the patient gently and quickly, and assist those with mobility problems;
5. Instruct the patient to use slow and rhythmic deep breathing to relax both physically and psychologically, eliminate tension, distract attention and reduce pain;
6.For patients with herpes zoster in the chest and waist area, instruct them to wear loose and soft clothing, and not to wear chemical fiber clothing to reduce local irritation.