Incidence Of Postherpetic Neuralgia Research Articles

Early application of low-level laser may reduce the incidence of postherpetic neuralgia (PHN)

Postherpetic neuralgia (PHN) is difficult to treat, and currently there are no available treatments that effectively reduce its incidence. Low-level laser therapy (LLLT) has been proposed for indirect virus deactivation in treating recurrent herpes simplex infections. This study seeks to investigate whether LLLT could reduce the incidence of PHN. We retrospectively reviewed the incidence of PHN at the first, third, and sixth months after rash outbreak in 3 groups: the acute group of patients who received LLLT during the first 5days; the subacute group of patients who received LLLT during days 6 to 14 of the eruption; and the control group of patients who did not receive LLLT. There were 48, 48, and 154 patients in the acute, subacute, and control groups, respectively. After adjusting for confounding factors, including age, sex, and use of famciclovir, the incidence of PHN was significantly lower in the acute group versus the control group after 1 month (odds ratio [OR] 0.21, P = .006, 95% confidence interval [CI] 0.068-0.632), 3 months (OR 0.112, P = .038, 95% CI 0.014-0.886), and 6 months (OR 0.123, P = .021, 95% CI 0-0.606). The subacute group only had a lower incidence (OR 0.187, P=.032, 95% CI 0.041-0.865) after 3months when compared with the control group. This is a retrospective study lacking double-blind randomization, and the placebo effect may be a major concern. Lack of standardized and prospective evaluation measures is also a limitation of this study. Applying LLLT within the first 5days of herpes zoster eruption significantly reduced the incidence of PHN. LLLT may have the potential to prevent PHN, but further well-designed randomized controlled trials are required.

Effect of Repetitive Intracutaneous Injections with Local Anesthetics and Steroids for Acute Thoracic Herpes Zoster and Incidence of Postherpetic Neuralgia.

Treatment of established postherpetic neuralgia (PHN) is difficult and often disappointing. In this study, we assessed the efficacy of repetitive intracutaneous injections with local anesthetics and steroids in acute thoracic herpes zoster (HZ) pain, herpetic eruption, and incidence of PHN. Ninety-three patients with acute thoracic HZ were randomly assigned to receive a standard treatment of antiviral medication with p.o. analgesics or the standard treatment with the addition of repetitive intracutaneous injections of a local anesthetic and steroid mixture. Patients were permitted to take tramadol when the visual analog scale (VAS) ≥ 4. Pain assessment using VAS was conducted at the initial visit, as well as 1, 2, 4, 12, and 24 weeks after the end of the treatments. In comparison with the standard treatment group, the VAS scores of the intracutaneous injection group were significantly lower during the study. The intracutaneous injection group also reported shorter duration of pain and skin eruption than the control group ( P = 0.005 vs P < 0.001, respectively). At 1 month post-therapy, 12.8% patients in the intracutaneous injection group reported zoster-associated pain, compared with 47.8% in the standard treatment group ( P < 0.001). At 3 and 6 months post-therapy, the incidence of PHN was still significantly lower in the intracutaneous injection group than the standard treatment group. EuroQol VAS scores were significantly higher in the intracutaneous injection group vs standard treatment group (P < 0.001). Repetitive intracutaneous injections with local anesthetics and steroids along with standard treatment significantly reduce the duration of pain and herpetic eruption and incidence of PHN.

Clinical and immunologic features of recurrent herpes zoster (HZ)

Recurrent herpes zoster (HZ) is thought to be rare, but there have been few large-scale studies of recurrent HZ. We conducted a large-scale prospective cohort study to characterize recurrent HZ. We examined 12,522 participants aged 50years or older in Shozu County and followed them up for 3years. We compared the incidence of HZ and postherpetic neuralgia, severity of skin lesions and acute pain, cell-mediated immunity, and varicella-zoster virus-specific antibody titer between primary and recurrent HZ. A total of 401 participants developed HZ: 341 with primary HZ and 60 with recurrent HZ. Skin lesions and acute pain were significantly milder and the incidence of postherpetic neuralgia was lower in patients aged 50 to 79years with recurrent HZ than in those with primary HZ. Varicella-zoster virus skin test induced a stronger reaction in patients aged 50 to 79years with recurrent HZ than in those with primary HZ. Information on previous HZ episodes was self-reported by participants, so it could not be confirmed that they actually had a history of HZ. Recurrent HZ was associated with milder clinical symptoms than primary HZ, probably because of stronger varicella-zoster virus-specific cell-mediated immunity in the patients with recurrence.

Herpes zoster and the search for an effective vaccine.

Primary infection with varicella zoster virus (VZV), an exclusively human neurotrophic alphaherpsesvirus, results in varicella, known more commonly as chickenpox. Like other alphaherpesviruses, VZV establishes latency in the sensory ganglia and can reactivate to cause herpes zoster (also known as shingles), a painful and debilitating disease, especially in elderly and immunocompromised individuals. The overall incidence of herpes zoster in Europe and the United States is three per 1000 people, but increases sharply after 60 years of age to 10 per 1000 people. Zostavax® is a vaccine approved by the Federal Drug Administration for the prevention of herpes zoster. Unfortunately, this vaccine reduces the incidence of disease by only 51% and the incidence of post-herpetic neuralgia by 66·5% when administered to those aged 60 and older. Moreover, it is contraindicated for individuals who are immunocompromised or receiving immunosuppressant treatments, although they are at higher risk for herpes zoster compared to immune-competent older individuals. This paper reviews VZV pathogenesis, host responses and current vaccines available to prevent herpes zoster.

Epidemiology of Postherpetic Neuralgia in Korea: An Electronic Population Health Insurance System Based Study.

Postherpetic neuralgia (PHN) is a disease entity defined as persistent pain after the acute pain of herpes zoster gradually resolves. It is associated with impaired daily activities, resulting in reduced quality of life. General epidemiological data on PHN is necessary for the effective management. However, data on the epidemiology of PHN in Korea is lacking. The aim of this study was to evaluate the epidemiological features of PHN in the general population.We used population-based medical data for 51,448,491 subscribers to the Health Insurance Service in the year of 2013 to analyze of PHN epidemiology in Korea, such as the incidence, regional distribution, seasonal variation, and healthcare resource utilization. Total number of patients and medical cost on PHN were analyzed from 2009 to 2013.Findings indicate that the incidence of PHN in Korea was 2.5 per 1000 person-years, which was strongly correlated with age and sex. There were no differences in seasonal variation or regional distribution. The medical cost increased steadily over the study period. When admitted to general hospitals, patients with PHN were mainly managed in the dermatology and anesthesiology departments.The incidence and prevalence rates of PHN in Koreans appear to be considerably higher compared to those in western populations, while the sex and age predisposition was similar. Considering that the pain associated with PHN can have a marked impact on a patient's quality of life resulting in a medicosocial economic burden, anesthesiology physicians have an important role in primary care in Korea. Future research on the cost-effectiveness of the management of PHN is needed.

Thin cotton moxibustion combined with plum-blossom needle in treatment of herpes zoster: a controlled trial

ObjectiveTo compare the difference of clinical efficacy of thin cotton moxibustion combined with plum-blossom needle and western medication in treatment of herpes zoster. MethodEighty patients with herpes zoster were divided into thin cotton moxibustion group (group A, n=40) and western medication group (group B, n=40) according to the sequence of admission. Patients in group A received thin cotton moxibustion that the colton was used as thin as a cicada's wings, combined with plum-blossom needle, and patients in group B received intravenous infusion with 0.25 g of acyclovir once a day, and acyclovir ointment application on affected part for 3–5 times per day. Five days were considered as a course of treatment. Analgesic effect and the incidence of postherpetic neuralgia were observed after two consecutive courses. ResultThe total effective rate was 97.5% (39/40) in group A, and 80.0% (32/40) in group B (P<0.05); it was shown from the comparison of course between two groups that the cure rate after one in group A was markedly higher than that in group B (P<0.01, P<0.05); the differences in effectual time and analgesic time between group A and group B were statistically significant (P<0.05); after treatment, the incidence of postherpetic neuralgia in group A was markedly lower than that in group B (P<0.05). ConclusionThin cotton moxibustion combined with plum-blossom needle in treatment of herpes zoster can obviously shorten the time of therapy, effectively control pain, and reduce the incidence of postherpetic neuralgia.

Prednisolone can Prevent Post-Herpetic Neuralgia in Post-Kidney Transplant Recipient

Background and study aim: Post-herpetic neuralgia (PHN) is a neuropathic painful condition that is one of the most frequent complications of an acute herpes zoster infection. Till now, there is no general agreement on the definition of PHN. Some studies described a wide range of definitions, including any pain that comes after disappearing of the herpes zoster rash, whereas other studies applied the definition of pain that persist for more than one or two months after the onset of rash. The aim of this study was to assess the effect of oral prednisolone with antiviral therapy on prevention of post-herpetic neuralgia in post-kidney transplant recipient. Patients and methods: 40 patients were divided into two groups, the first one (group A) involved 20 patients who had renal transplant within the past five years and have received oral prednisolone (10 mg/day) and the second one (group B) involved also 20 patients but they are immune-competent without co-morbidity. Follow up was done at one, three and six months to assess the pain. Results: At time of admission and discharge, there was significant difference between group A and group B as regard zoster pain. The same significance was observed between two groups during follow up after one and three months and not observed after six months. Conclusion: Oral corticosteroid can promote modest benefits in decreasing the pain of herpes zoster and the incidence of PHN in post-kidney transplant recipient.

Efficacy of low dose gabapentin in acute herpes zoster for preventing postherpetic neuralgia: a prospective controlled study.

Postherpetic neuralgia (PHN) is a sequela of herpes zoster that adversely affects quality of life seriously. The risk factors for PHN are well known but the effective interventions that reduce the incidence of PHN are less studied. The objective of this study is to evaluate the efficacy of treatment with gabapentin in patients with acute herpes zoster for preventing PHN. We performed a prospective randomized controlled study of 120 participants diagnosed with acute herpes zoster, aged 50 and over and complaining moderate to severe pain. All patients were treated with valacyclovir and acetaminophen. Half of the participants were assigned to the gabapentin group and received gabapentin 300 mg three times a day additionally. The intensity of pain at every visit and the incidence of PHN in both groups were measured. Total 52 and 49 patients in the gabapentin group and the control group, respectively, had completed 12 weeks of follow-up period. Although the incidence of PHN was higher in the control group, the difference was not statistically significant (6.1% vs. 3.8%, p = 0.67). Our results indicate that the use of low-dose gabapentin in acute herpes zoster seems not effective in the prevention of PHN.

A Study of Intravenous Administration of Vitamin C in the Treatment of Acute Herpetic Pain and Postherpetic Neuralgia.

BackgroundAlthough there are several available management strategies for treatment of both acute pain of herpes zoster (HZ) and postherpetic neuralgia (PHN), it is difficult to treat them adequately.ObjectiveThe aim of this study was to evaluate the efficacy of intravenously administrated vitamin C on acute pain and its preventive effects on PHN in patients with HZ.MethodsBetween September 2011 and May 2013 eighty-seven patients who were admitted for HZ were assessed according to age, sex, underlying diseases, duration of pain and skin lesion, dermatomal distribution, and PHN. It was a randomized controlled study, in which 87 patients were randomly allocated into the ascorbic acid group and control group. Each patient received normal saline infusion with or without 5 g of ascorbic acid on days 1, 3, and 5 then answered questionnaires that included side effects and pain severity using visual analogue scale on days 1, 2, 3, 4, and 5. After discharge, the severity of pain was obtained at out-patient clinic or by telephone on weeks 2, 4, 8, and 16.ResultsThere was no differences in severity of pain on patients' age, sex, underlying diseases, duration of pain and skin lesion and dermatomal distribution between two groups (p>0.05). Since 8th week, pain score in ascorbic acid treatment group was significantly lower than control group (p <0.05). The incidence of PHN was significantly lower in the treatment group compared to control group (p=0.014). The changes of overall pain score was significantly different between the two groups (p<0.05).ConclusionIntravenously administered ascorbic acid did not relieve acute HZ pain; but is effective for reducing the incidence of PHN.

Post-herpetic neuralgia

BACKGROUND AND OBJECTIVES: Post-herpetic neuralgia is defined as pain persisting for more than three months after the resolution of skin eruptions observed in herpes-zoster. Post-herpetic neuralgia incidence is quite variable, increases with age, being more frequent among patients aged over 60, and is associated to reduced quality of life of affected individuals. The objective of this review is to discuss key aspects of post-herpetic neuralgia, particularly its pathophysiology, clinical signs, diagnosis, prevention and treatment. CONTENTS: Post-herpetic neuralgia pathophysiology is poorly understood and involves peripheral and central nervous system mechanisms. Associated clinical signs are variable and represented mainly by pain with neuropathic features and skin changes in dermatomes previously affected by herpes-zoster. Post-herpetic neuralgia prophylactic vaccination seems to be the best preventive option. Diagnosis of post-herpetic neuralgia is largely clinical and treatment involves an early-stage, multimodal approach. Among techniques described in the literature, there is pharmacological treatment which, when not effective, requires the implementation of interventional techniques. CONCLUSION: Post-herpetic neuralgia is a complex entity and should be treated in a multidisciplinary way aiming at improving patients' quality of life.

Evaluation of the efficacy of different regimens in decreasing the incidence of postherpetic neuralgia

Introduction Herpes zoster (HZ) is a transient disease caused by reactivation of the varicella-zoster virus that remains dormant within the dorsal root ganglia after varicella. Major complications, such as PHN, often defined as pain that persists for 3 months or more, may occur after the onset of the HZ rash. Our aim is to compare between two regimens in relieving HZ pain and their effects in preventing progression to PHN. Patients and methods This study was carried out on 80 outpatients of both sexes who had acute herpetic pain. Group D, which included 40 patients, received acyclovir (800 mg/day), pregabalin (600 mg/day), and fentanyl transdermal patch (75 μg/each 3 days). Group E included 40 patients who received acyclovir (800 mg/day), pregabalin (600 mg/day), and an epidural injection of bupivacaine with 80 mg methylprednisolone twice weekly over 14 days. Results In terms of pain assessment, in group D, there was a significant analgesic effect up to the sixth month compared with the first day. However, an insignificant analgesic effect was observed on the fourth and seventh days, with significant changes afterwards up to the sixth month in group E. The incidence of PHN was observed in 40 and 20% of all patients, whereas the incidence of allodynia was observed in 57.5 and 22.5% of patients in groups D and E, respectively. The incidence of herpetic pain in children reaches 2.5%, but usually does not progress to PHN. Conclusion Acyclovir together with a pregabalin anticonvulsant results in significant pain relief, although it does not reduce the incidence of PHN. However, use of epidural methylprednisolone leads to a lower analgesic effect in addition to less significant effect in decreasing the incidence of PHN.

Les vaccins contre le zona : efficacité, sécurité, et rapport coût/bénéfices

A vaccination against herpes zoster and its complication is available in France since June 2015. Its exact benefit for public health is still controversial and its level of protection is not optimal. All those reasons seem to suggest a low acceptation rate from general practitioners. To evaluate the effectiveness, the safety, and the cost/benefit ratio of the vaccination against herpes zoster in people aged 50 year or over. Systematic review in Medline and PubMed with research by key words: "herpes zoster vaccine", "zoster vaccine" and "post herpetic neuralgia vaccine". Randomized and observational studies published in English and French language have been selected by two readers. On 1886 articles identified, 62 studies were included in this systematic review of which 21 randomized trials, 21 observational studies, and 17 medico-economic studies concerned the unadjuvanted vaccine. Considered studies showed an effectiveness of 50% against herpes zoster and 60% on post-herpetic neuralgia incidence of the unadjuvanted vaccine. Five randomized controlled studies were identified for the adjuvanted vaccine. The overall effectiveness of this vaccine was > 90% whatever the age of subjects including those over age 70 and 80. The medico-economic studies conducted in many countries have shown that vaccine policies were beneficial in individuals aged 60 years or over. Most of data of effectiveness, and tolerance result from 2 large controlled studies only (SPS and ZEST) for the unadjuvanted vaccine and only one for the adjuvanted vaccine. Despite controversy and few uncertainties, the vaccine significantly reduces herpes zoster and its complication incidence. In terms of public health objectives, it reduces the burden of the disease and has a positive medico-economic impact. Preliminary data concerning the adjuvanted vaccine, whilst very promising, are still too limited. Up to now, no group of people with particularly high risk of herpes zoster-related complication who will beneficiate the most of the vaccination has been identified yet and only an age criteria has been considered for the recommendation.

Local Injection of Methylcobalamin Combined with Lidocaine for Acute Herpetic Neuralgia.

To determine the efficacy of methylcobalamin combined with lidocaine for acute herpetic neuralgia. Randomized controlled trial with longitudinal analysis. The authors recruited 204 patients (>50 years) with T5-10 dermatomal acute herpetic neuralgia with rash onset within 7 days. Patients were divided into two groups based on the time of onset: immediate-early (IE, 1-3 days) and early stage (ES, 4-7 days) groups and then subdivided randomly into control (IE-Ctl, ES-Ctl) and treatment (IE-Tr, ES-Tr) groups. Control groups received intramuscular methylcobalamin in addition to local lidocaine injection, while treatment groups received local methylcobalamin combined with lidocaine injection for 14 days. Treatment efficacy was assessed based on rash healing time, alteration in pain intensity, and interference with quality of life. Multilevel mixed modeling and survival analysis were employed to examine treatment responses. There was no significant difference in the rash healing time between IE and ES. The mean pain scores in IE-Tr (2.4 ± 0.7) and ES-Tr (1.3 ± 0.7) decreased significantly compared with those in the control groups. The median satisfactory response time was 6 days in ES-Tr and 11 days in IE-Tr. The benefit ratio for ES-Tr versus IE-Tr was 14.94. The subjects in IE-Tr and ES-Tr had higher quality of life scores (81.2 ± 6.9 vs 88.3 ± 8.6, respectively) than those in the control groups. The incidence of postherpetic neuralgia was 1.1% at 3 months. Local methylcobalamin combined with lidocaine, optimally administered within 4-7 days of onset, may be an effective therapeutic option for acute herpetic neuralgia.

Evaluation of Varicella Zoster Prophylaxis after Allogeneic Hematopoietic Cell Transplantation Using Valacyclovir Followed By Vaccination

Rationale: Varicella zoster virus (VZV) disease occurs frequently post allo-HCT. While cutaneous disease is often complicated by debilitating post-herpetic neuralgia (PHN), visceral or CNS disease can be fatal. Studies have demonstrated that VZV disease is reduced during prophylaxis with acyclovir; however, patients frequently develop VZV disease after discontinuation of acyclovir. Recently, the varicella vaccine has been found to be safe and immunogenic post allo-HCT. The optimal prophylactic strategy for VZV disease post allo-HCT has not been established. Here we present a retrospective single-center study, comparing pre-2007 prophylaxis, which consisted of less than 2 years of post allo-HCT acyclovir, with post-2007 prophylaxis, which consisted of 2 years of valacyclovir prophylaxis followed by live attenuated varicella vaccination. Objective: To evaluate the hypothesis that the cohort treated with the pre-2007 strategy ("old strategy") had a higher cumulative incidence of VZV disease and PHN compared to the cohort treated with the post-2007 strategy ("new strategy"). Methodology: Charts of patients undergoing allo-HCT in Calgary between January 2004 and June 2011 were reviewed. VZV disease was defined as clinical zoster or visceral/CNS disease confirmed by immunostain or PCR. PHN was defined as pain in the affected dermatome persisting more than 3 months after the onset of the rash. Cumulative incidence of VZV disease and PHN were compared using competing risks regression (Fine-Gray), treating relapse, graft failure, second malignancy and death as competing risks. Results: 482 patients underwent first allo-HCT in Calgary during the review period. 21 were excluded due to inadequate data. 119 were treated with the new strategy, 116 with the old strategy and 226 experienced a competing event while on prophylaxis. Some patients in the old strategy group received late VZV vaccination (at &gt;2 years). The old strategy was associated with a trend towards higher cumulative incidence of VZV disease (sHR 1.57, 95% CI 0.95-2.62, p=0.08) and with significantly higher cumulative incidence of PHN (sHR 9.94, 95% CI 1.24-80.05, p=0.03). 3 episodes of VZV disease in the old strategy group and 7 episodes in the new strategy group were associated with deviation from protocol (most associated with medication noncompliance). When events associated with protocol deviation were excluded, the old strategy led to a significantly higher cumulative incidence of VZV disease (HR 2.40, 95% CI 1.32-4.38, p=0.004) and PHN was not observed in the new group (p= &lt;0.01). Vaccination was safe; however 10% of patients developed immediate or late cutaneous VZV disease. PHN was not observed in the patients who developed the VZV disease post vaccination. Conclusions: The new strategy was associated with a trend towards less VZV disease and significantly less PHN. Noncompliance was a significant contributor to VZV disease in the new strategy group. If compliance is ensured, the new strategy significantly reduces VZV disease and eliminates PHN. Disclosures No relevant conflicts of interest to declare.

A Study on the Connection between the Incidence of Postherpetic Neuralgia and Serum Ionized Calcium.

Herpes zoster (HZ) is an acute virus infectious disease mainly affecting middle-aged and elderly people. The morbidity rates of HZ in the age group of 50–59 years and 60–69 years are, respectively, 46 and 69 (per year, per 10,000 people). The age groups of 70–79 years and 80–89 years have a much higher rate of 95 and 109 (per year, per 10,000 people), respectively.[1,2] Postherpetic Neuralgia (PHN) is a neuropathic syndrome which manifests as ongoing pain along the cutaneous nerve/s located in the area of prior HZ rash and typically involves one or more of the following types of pain: spontaneous aching or burning; paroxysmal shooting; and allodynia and hyperalgesia. While in the majority of cases, this pain will resolve within a year of initial rash presentation, for some patients the pain may persist for 5 years or more. As expected, given the relationship to HZ, the incidence of PHN increases markedly with age. However, the incidence is also linked to the severity of the pain experienced during the HZ episode. Those patients experiencing the highest levels of acute pain during HZ presentation are most at risk of developing PHN. PHN is also more prevalent among female than male HZ paitents.

Is herpes zoster vaccine safe and effective for preventing zoster and postherpetic neuralgia?

Evidence-Based Answer The herpes zoster vaccine is effective in preventing herpes zoster (SOR: B, large RCT). The zoster vaccine does not further reduce the incidence of postherpetic neuralgia (PHN) beyond simply reducing the incidence of herpes zoster (SOR: B, large RCT). The vaccine does cause localized reactions in about half of patients (regardless of a history of prior herpes zoster), but serious adverse events are rare (SOR: A, systematic review).

Local Administration of Methylcobalamin and Lidocaine for Acute Ophthalmic Herpetic Neuralgia: A Single-Center Randomized Controlled Trial.

To determine the therapeutic efficacy of combined methylcobalamin and lidocaine for acute ophthalmic herpetic neuralgia (AOHN). Based on the onset, patients with AOHN (n=98) were randomly allocated into groups A (≤3days) and B (4 to 7days) and then subdivided into control (A0, B0; received intramuscular methylcobalamin in addition to local lidocaine injection) and treatment (A1, B1; received local injection of the methylcobalamin and lidocaine combination for 14days) groups. Treatment efficacy was assessed based on rash healing time, alteration of pain intensity, and interference with quality of life. Multilevel modeling and survival analysis were performed. The time (hours) to start and full opening of the affected eye and the time (hours) to start and full crusting were significantly reduced in both treatment groups (P<0.05 vs. controls). The mean pain scores in A1 (2.6±0.7) and B1 (1.2±0.8) decreased significantly compared with those in A0 (7.0±1.7) and B0 (5.6±1.9), and the difference between the two therapeutic strategies significantly increased over time. The median minimum intervention time was 6days in B1 and 11days in A1. The incidence of postherpetic neuralgia (PHN) was 2.04% at 3months. Methylcobalamin combined with lidocaine mediated detumescence and improved cutaneous healing of the affected area, as well as a significant and sustained analgesic effect on AOHN. The incidence of PHN was also significantly decreased. Local methylcobalamin intervention within 4 to 7days of onset may be an effective therapeutic option for AOHN.

Risk Factor and Prevention of Postherpetic Neuralgia.

Herpes zoster (HZ) and postherpetic neuralgia (PHN) are common diseases in a pain clinic. In Korea, the rate of clinical visits due to the incidence of herpes zoster was 7.93-12.54/1000 annually [1]. PHN is a painful neuropathy and the most common complication of HZ. A complete recovery from PHN is difficult for doctors despite of proper HZ treatment. In spite of the treatment, some patients suffered from severe PHN for several years. Therefore, the most important aspects are the risk factor of PHN and the method of prevention of PHN. In this issue of the Korean Journal of Pain (KJP), Jung et al. [2] reported the incidence of HZ in Cheonan, Korea. The results show that patients 50 years and older have a higher incidence of HZ, and the most common site of HZ was the thoracic nerve (47.9%), followed by the trigeminal nerve (21.4%). The incidence rate was similar to the affected site of PHN (thoracic area: 52.9%, trigeminal area: 15.6%) in Korea [3]. In patients who suffer from HZ, the risk factors of PHN are old age, presence of a painful prodrome, severe pain of HZ, severe rash, and immuno-compromised status [4,5,6]. In patients with HZ over 60 years, up to 25% progressed to PHN [7]. The proportion of PHN increases steadily from young ages up to 80-84 years [8]. Therefore, patients who are elderly and possess the risk factor with HZ must undergo more intensive treatment. The main treatment of HZ is medication and interventional therapy. Taking antiviral medication beginning within 72 hrs of rash onset is usually recommended [7,9,10]. Two meta-analyses suggest that the antiviral medication can reduce the overall duration of pain and incidence of PHN [11,12]. Epidural injection with a steroid within 2 months of HZ development is also recommended for the prevention of PHN [13]. In the previous survey of Korea, epidural injection was the most commonly performed interventional treatment in PHN patients [3]. Other interventions such as paravertebral block, peripheral block and sympathetic block are clinically effective for the treatment of HZ and PHN. For evidence-based medicine of interventional treatment of HZ and PHN, the investigations of randomized controlled trials regarding the interventions will be necessary. In this issue, Jeon et al. [10] described the prevention and treatment of HZ and PHN. They mention that vaccination against varicella zoster virus (VZV) can be the first line for the prevention of HZ and PHN. A previous review article reported that vaccination of VZV reduced morbidity from HZ and PHN [14]. Vaccination of VZV reduced the occurrence of herpes zoster by approximately 70% in individuals aged 50-59 years old [15]. In persons 60 years or older, the vaccination reduced the burden of illness from HZ by 61.1% and the risk of PHN by 66.5% [16]. Therefore, the vaccination of patients over 50 years old can be effective for the prevention of HZ and PHN. Although PHN is difficult to treat, early and intensive treatment of patients with HZ can reduce the occurrence of PHN. In healthy elderly people, a vaccination of VZV can also decrease the incidence of HZ and PHN.

VZV skin-test reaction, but not antibody, is an important predictive factor for postherpetic neuralgia

BackgroundThe decline of cell-mediated immunity (CMI) is thought to be related to the risk of postherpetic neuralgia (PHN) as well as herpes zoster (HZ). However, the relationship between immunological condition and the incidence of PHN is still unclear. ObjectiveWe conducted a large-scale prospective cohort study to clarify the relationship between immunological factors for varicella-zoster virus (VZV) and the incidence of PHN. MethodsWe carried out a cohort study on VZV immunity in a population living on an island cluster, Shozu County in Japan, and examined the people who developed HZ during a follow-up period of 3 years, with a focus on the relationship between cell-mediated and humoral immunity and the incidence of PHN. A total of 12,522 people over the age of 50 were enrolled in this study, and 401 registrants were diagnosed with HZ, including 79 PHN cases. We evaluated anatomical location and severity of skin lesion, acute pain severity, presence or absence of abnormal sensations, CMI assessed by VZV skin test, and VZV-specific antibody titer measured by serological tests. ResultsThe incidence of PHN was significantly associated with a weak response to the VZV skin test, as well as facial or lumbosacral localization of skin rash, severe skin lesion, severe acute pain, and presence of abnormal sensations, but not related to VZV-specific antibody titer. ConclusionThe incidence of PHN is significantly associated with the decline of VZV-specific CMI, but not related to VZV-specific humoral immunity.

Zoster Vaccine and the Risk of Postherpetic Neuralgia in Patients Who Developed Herpes Zoster Despite Having Received the Zoster Vaccine.

Although it is evident that zoster vaccination reduces postherpetic neuralgia (PHN) risk by reducing herpes zoster (HZ) occurrence, it is less clear whether the vaccine protects against PHN among patients who develop HZ despite previous vaccination. This cohort study included immunocompetent patients with HZ. The vaccinated cohort included 1155 individuals who were vaccinated against HZ at age ≥60 years and had an HZ episode after vaccination. Vaccinated patients were matched 1:1 by sex and age with unvaccinated patients. Trained medical residents reviewed the full medical record to determine the presence of HZ-related pain at 1, 2, 3, and 6 months after HZ diagnosis. The incidence of PHN was compared between vaccinated and unvaccinated -patients. Thirty vaccinated women (4.2%) experienced PHN, compared with 75 unvaccinated women (10.4%), with an adjusted relative risk of 0.41 (95% confidence interval, .26-.64). PHN occurred in 26 vaccinated men (6.0%) versus 25 unvaccinated men (5.8%), with an adjusted relative risk of 1.06 (.58-1.94). These associations did not differ significantly by age. Among persons experiencing HZ, prior HZ vaccination is associated with a lower risk of PHN in women but not in men. This sex-related difference may reflect differences in healthcare-seeking patterns and deserve further investigation.