Herpes zoster is a common skin disease caused by varicella-zoster virus (VZV) infection. With the accelerated aging process in China, increasing work stress, the continued rise in the incidence of AIDS, and other factors causing increased resistance in the body, the incidence of herpes zoster is on a significant rise.
The disease is self-limiting and rarely life-threatening, but some patients, especially the elderly, are prone to complications of post-herpetic neuralgia, which seriously affects the quality of life of patients and family members. Early non-standardized treatment is one of the important factors contributing to this problem, so it is necessary to pay attention to it.
I. Early diagnosis and timely standardized antiviral treatment are important
Herpes zoster usually has local pain 1 to 3 days before the rash occurs, and at this time, the rash is often misdiagnosed as pleurisy, pleurisy, or herpes zoster based on different sites.
It is often misdiagnosed as pleurisy, pneumonia, cholecystitis, cholelithiasis, myocarditis, angina pectoris, myocardial infarction, gastric ulcer, kidney stone and other medical and surgical diseases due to the lack of rash, which not only delays the diagnosis but also brings a large economic burden to the patient. The pain caused by herpes zoster has more significant characteristics of its own.
The pain is essentially neuralgia, so it manifests as burning pain, pins and needles, with local numbness, and the pain does not increase with breathing or coughing, nor does it radiate to other parts of the body, unlike the pain caused by visceral diseases. Local pressure and snap pain are not obvious on physical examination, but pain can be induced by light touch or by gently rubbing the local skin with clothing. This condition is called allodynia, and is easily distinguished from pain not caused by herpes zoster. Recognizing the characteristics of herpes zoster pain allows for early diagnosis and timely appropriate treatment, especially in older patients, where early antiviral therapy is important.
Whether early and aggressive treatment can alter the natural course of herpes zoster has been debated, but most studies agree that antiviral therapy is an important treatment. Antiviral therapy may control blister formation in a timely manner, promote lesion regression, and may shorten the duration of herpes zoster pain and prevent the occurrence of postherpetic neuralgia. To ensure the effectiveness of antiviral, standardized and rational application is the key. The main aspects are as follows.
① The choice of antiviral timing. In general, the best time to start antiviral treatment is within 72 hours after the rash is formed, and it can be equally effective within 1 week for some patients who occur in the head or have heavy skin lesions.
②The choice of route of administration. The general choice of drugs includes acyclovir and famciclovir, the former is poorly absorbed orally and often requires intravenous administration, but intravenous administration is too fast, or the dose is too large, and the blood concentration is high for a short time, but it may put a greater burden on the kidneys and even induce the risk of renal failure. Therefore, intravenous acyclovir is not the best choice and is risky, mostly requiring hospitalization and increasing the financial burden of patients. Famciclovir is better absorbed orally, and the blood concentration is stable, reducing intravenous infusion and hospitalization, thus reducing the patient’s burden.
(iii) Adequate dose. Since VZV is 2 to 10 times less sensitive to commonly used nucleoside analogue antivirals than herpes simplex virus, such that the same dose used against herpes simplex virus infection cannot be used to treat herpes zoster. Generally, oral vaxilovir at 1 g each time, 3 times a day is required to effectively achieve antiviral effects.
④ Appropriate course of treatment. Usually the course of antiviral treatment is 7~10 days, or the crusting of the lesions is sufficient, and a course of more than 10 days is unnecessary.
II. Reasonable application of glucocorticoids
The use of glucocorticoids (referred to as hormones) for shingles has been controversial. Traditionally, it is believed that giving hormones early in the course of herpes zoster can effectively reduce inflammation and stop the inflammation.
Traditionally, it was believed that the administration of hormones early in herpes zoster could effectively reduce inflammation, prevent the destructive effects on ganglia and nerve fibers, and reduce the occurrence of postherpetic neuralgia, thus becoming a routine clinical treatment. With the application of rigorous clinical studies, especially evidence-based medicine, the value of hormone use in the treatment of herpes zoster has been exaggerated and even misuse exists.
Large-sample multicenter clinical studies have confirmed the lack of clear and definite evidence of the effectiveness of hormones in preventing postherpetic neuralgia, but they can promote the healing of herpes zoster acute lesions and reduce the pain of acute lesions. Therefore, it is recommended that it can be used selectively if there are no contraindications, and it can be used appropriately in patients over 50 years of age with severe lesions and significant pain, especially in patients with hearing impairment or facial palsy, and in the absence of severe hypertension, diabetes, or infection. The starting dose of adult prednisone is 30-40mg per day, divided into 2-3 oral doses, and then reduced by about 10mg every 7 days for a course of 3 weeks.
The use of hormones should be weighed against the pros and cons. The following aspects should be noted when using.
①Hormones should be used in combination with sufficient amount of antiviral drugs to prevent the spread of virus due to the use of hormones alone;
②Theoretically, hormones can reduce inflammation and shorten the healing time of skin lesions, but if skin erosion or ulceration has already occurred, unreasonably long courses of hormones applied in larger doses may affect the healing of the wound;
Some patients with herpes zoster have a benign self-limiting recovery, especially young and middle-aged patients with mild pain, and the routine use of hormones is not necessary;
④Severe patients, especially the elderly, often have various comorbidities, such as hypertension, diabetes mellitus, chronic infections, etc. The use of hormones in such patients without selection or without balancing the pros and cons of pain obviously increases the risk of side effects of hormones;
(5) The use of hormones is not standardized in terms of drug dosage, dose and course of treatment. Sometimes, the choice of slow-release dosage form seems to be very convenient and improves compliance, but insufficient dosage in the early stage and unnecessary slow-release too long in the later stage are both unreasonable, which obviously do not really play a proper role;
(6) Some erroneously believe that hormone is an important measure to effectively prevent postherpetic neuralgia, ignoring the fact that early active standardized antiviral therapy is the key to effectively stop the occurrence of postherpetic neuralgia.
Third, the choice of pain control measures
Herpes zoster-related pain, especially post-herpetic neuralgia, is an important factor that seriously affects patients’ quality of life, and effective
Pain relief is an important part of shingles treatment. Pain associated with herpes zoster can be present from days before the rash appears to months or even years after the rash heals. The mechanism of occurrence is not well understood, but increased sensitivity of peripheral and central nerves to pain, known as pain sensitization, is an important basis for its occurrence. To reduce or stop the occurrence and development of herpes zoster pain, in addition to the antiviral and rational application of hormones mentioned earlier, the following aspects are noted in the strategy of pain control.
①The application of CNS excitatory drugs such as doxepin and amitriptyline can be applied earlier in the acute phase of herpes zoster rash occurrence, especially in patients with more pronounced pain manifestations;
②Select sedative or antiepileptic drugs that inhibit central nervous excitability, such as gabapentin and pregabalin, are more important than drugs with analgesic effects alone;
(3) Since pain mostly originates from central or peripheral nerve excitability enhancement, local treatment at the pain site such as topical drugs, drug closure, surgical intervention, etc. has certain limitations, and standardized and reasonable systemic drug therapy is more critical.
Fourth, avoid using some unreasonable treatment measures
In the domestic treatment of herpes zoster, there are some clinical treatment irrational phenomenon, not only can not play a therapeutic role, but also can produce side effects of drugs, and bring a greater economic burden to patients. It is reflected in the following aspects.
① Irrationality in the selection of antiviral drug types. The choice of antiviral drugs for herpes zoster is mainly nucleoside analogues, and the efficacy of other antiviral drugs is not very certain. Also nucleoside antivirals, acyclovir and famciclovir are the first choice of treatment, not only because VZV is more sensitive to these two drugs, and the safety is also relatively high. Ganciclovir mainly targets cytomegalovirus infection and often causes immunosuppressive effects, causes leukopenia and other adverse effects, and is clearly inappropriate for use in patients with pre-existing immunocompromised herpes zoster. Sodium phosphonate is also used in the treatment of herpes zoster, which is mainly directed against drug-resistant herpes viruses. Since herpes zoster viruses rarely develop drug resistance, it is clear that routine use in the treatment of herpes zoster also lacks rationality.
② The use of immunomodulators. The basis for the development of herpes zoster is a decrease in body resistance, and the clinical choice of some immunomodulators such as interferon, transfer factor, thymidine, BCG polysaccharide nucleic acid, etc., in the expectation of improving the patient’s resistance, lacks clinically valid evidence and is not necessary. Since the basis of the pathogenesis of herpes zoster is a low cellular immunity specific to the herpes zoster virus, once the disease has developed on the one hand the virus replicates to produce herpes and on the other hand the replicating virus can effectively stimulate the specific cellular immunity of the organism, which is sufficient to make the organism protected. Therefore, patients with herpes zoster rarely recur. Abuse of immunomodulators not only has no clear efficacy, but may produce some adverse effects and increase the economic burden of patients.
(iii) The use of neurotrophic drugs. For many years it was believed that nerve damage was an important reason for the occurrence of herpes zoster combined with neuralgia. Recent studies have found that herpes zoster neuralgia does not occur with significant organic neuropathy, but mostly with functional neurophysiological changes, so the routine use of neurotrophic agents such as vitamin B1 and vitamin B12 is clearly unnecessary and lacks clinical evidence to support its positive effect.
The application of various therapies for herpes zoster must be based on an understanding of the mechanisms of disease occurrence, and it is necessary to conduct multicenter, large-sample, double-blind controlled studies to guide clinical treatment through evidence-based medicine.