Cutaneous nerve changes in zoster

Postherpetic granulomatous dermatitis occurring in the setting of immune checkpoint inhibitor therapy: A case report

We report a case of a 72-year-old man presenting with a 2-month history of a persistent, painful rash of the chest, axilla, and back. He had a history of recently resolved varicella zoster virus reactivation in the same distribution of the current rash and metastatic malignant melanoma treated with nivolumab and ipilimumab. The histopathology was consistent with granulomatous dermatitis (GD), and a diagnosis of postherpetic isotopic response manifesting as GD was made. Given the paucity of reported cases of postherpetic GD in the setting of treatment with immune checkpoint inhibitors (ICIs), we discuss the clinicopathologic features of this case and potential mechanisms by which ICIs may contribute to the development of granulomatous disease.

Wolf's post-herpetic isotopic response: Infections, tumors, and immune disorders arising on the site of healed herpetic infection

Herpes simplex viruses (HSV-1/HSV-2) and varicella-zoster virus (VZV) have several characteristics in common. Both are epidermoneurotropic, cause skin eruptions accompanied by sensory symptoms (itch, pain), damage peripheral sensory nerve fibers and cutaneous nerve endings, and interfere with neuromediator release, which can alter local mechanisms of immune control. For this reason, herpes-infected areas may become a preferential location for the subsequent onset of immunity-related skin disorders (infections, tumors, and dysimmune reactions), an event first reported by a neurologist and focused on by two brothers, a dermatologist and a pediatrician. The phenomenon therefore named Wolf's post-herpetic isotopic response (PHIR) refers to the occurrence of a new skin disorder at the site of a previous and already healed herpetic eruption (herpes zoster in most cases). Until now, we have been able to gather 189 well-documented cases of PHIR (all reported in the reference section), but our list is far from being complete. Some of the most emblematic cases are briefly described here. In some circumstances, the opposite of PHIR occurs, with diffuse skin disorders or eruptions that selectively spare herpes-infected areas (Wolf's post-herpetic isotopic nonresponse). Experimental investigations with patch testing have been performed in seven patients who were sensitized to nickel and had had herpes zoster in the past years. The tests were carried out bilaterally on the affected dermatomes and on the unaffected contralateral ones. The uneven immune responses we obtained have shown that the immune behavior of an herpes zoster-affected dermatome can be different from that of the corresponding contralateral dermatome, thus supporting the existence of immune dysregulation in herpes-infected areas.

Dose related efficacy of gabapentin in acute herpetic neuralgia among geriatric patients

Background:

Herpes zoster is an intractable painful condition, more severe in elderly patients. The pain during the first 30 days of onset is known as Acute Herpetic Neuralgia. Multiple treatments using non-steroidal anti-inflammatory drugs (NSAIDs), opioids, and tricyclic anti-depressants are available, but their side effects limit their use in geriatric patients. Gabapentin is also used in chronic neuropathic pain; however, its role in acute herpetic neuralgia is less explored.

Aim:

This study was aimed to determine dose related efficacy and safety of gabapentin in reducing pain of acute herpetic neuralgia in geriatric patients.

Materials and Methods:

In this placebo-controlled, four-week trial including 56 subjects, 42 patients received gabapentin in the dosage of 300 mg (n=15), 600 mg (n=14), and 900 mg(n=13) per day in divided doses and 14 patients received placebo within 72 hours of onset of herpes zoster.

Results:

Subjects receiving gabapentin had a statistically significant reduction (P<0.0001) in visual analog scale (VAS) score as compared to placebo, emphasizing the efficacy of gabapentin in the treatment of acute pain associated with herpes zoster on each assessment (weeks 1, 2, 3, and 4). Gabapentin in doses of 600 mg/day and 900 mg/day was better than 300 mg/day in each visit. However, no difference was observed between gabapentin 600 mg/day and 900 mg/day group at any point of time (P>0.05).

Conclusion:

The results of this study show that gabapentin is effective in acute herpetic neuralgia in different doses with 600 mg/day being the more appropriate dose in terms of safety and efficacy.

Postherpetic Neuralgia: The Never-Ending Challenge

Postherpetic neuralgia (PHN) is defined as pain that persists 1 to 3 months following the rash of herpes zoster (HZ). PHN affects about 50% of patients over 60 years of age and 15% of all HZ patients. Patients with PHN may experience two types of pain: a steady, aching, boring pain and a paroxysmal lancinating pain, usually exacerbated by contact with the involved skin. Herpes zoster is initially a clinical diagnosis, based on the observation of a typical dermatomal distribution of rash and radicular pain. HZ is pathologically characterized by inflammatory necrosis of dorsal root ganglia, occasionally associated with evidence of neuritis, leptomeningitis, and segmental unilateral degeneration of related motor and sensory roots. Although acyclovir has been used successfully as standard therapy for varicella zoster virus (VZV) infection in the past decade, resistant strains of VZV are often recognized in immunocompromised patients. Therapy with acyclovir and the use of corticosteroids have been reported to prevent PHN in up to 60% of HZ patients. Management of chronic pain in PHN is more problematic. The only therapy proven effective for PHN in controlled study is the use of tricyclic antidepressants, including amitriptyline and desipramine. There is good evidence of efficacy from randomized trials that gabapentin and pregabalin (new anticonvulsant drugs) are of benefit in the reduction of pain from PHN. As alternative therapies, topical agents such as capsaicin, lidocaine or opioid analgesic treatment may give satisfactory results. Interventions with low risk, such as transcutaneous electrical nerve stimulation (TENS), are appropriate. Evidence is scant for the value of surgical and procedural interventions in general, although there are numerous, small studies supporting the use of specific interventions such as nerve blocks, neurosurgical procedures, and neuroaugmentation. Although antiviral agents are appropriate for acute HZ, and the use of neural blockade and sympathetic blockade may be helpful in reducing pain in selected patients with HZ, there is little evidence that these interventions will reduce the likelihood of developing PHN. Postherpetic neuralgia remains a difficult pain problem. This review describes the epidemiology and pathophysiology of PHN and discusses proposed mechanisms of pain generation with emphasis on the various pharmacological treatments and invasive modalities currently available.

Prevention of post-herpetic neuralgia: acyclovir and prednisolone versus epidural local anesthetic and methylprednisolone

BACKGROUND

Treatment of herpes zoster (HZ) includes the use of acyclovir with or without steroids. An alternative therapy is the epidural administration of local anesthetics with or without steroids. This trial compared the efficacy of these two treatment regimens in the prevention of post-herpetic neuralgia (PHN).

METHODS

Six hundred adults over 55 years of age with a rash of less than 7 days duration, and severe pain due to HZ, were enrolled and randomized to receive either intravenous acyclovir (10 mg/kg three times daily) for 9 days+prednisolone (60 mg per day with progressive reduction) for 21 days, or 6-12 ml bupivacaine (0.25%) every 6-8 or 12 h+methylprednisolone 40 mg every 3-4 days by epidural catheter during a period ranging from 7 to 21 days. Efficacy was evaluated at 1, 3, 6 and 12 months. PHN was assessed as pain and/or allodynia, and "abnormal sensations" (hypoesthesia, burning, itching, etc.). Statistical analysis was performed based on the intent-to-treat population.

RESULTS

In the 485 patients who completed the study, the incidence of pain after 1 year was 22.2% (51 patients of 230) after acyclovir+steroids, and 1.6% (4 patients of 255) after epidural analgesia+steroids. The incidence of abnormal sensations was 12.2% (28 patients) after acyclovir+steroids, and 4.3% (11 patients) in group B.

CONCLUSIONS

Epidural administration of local anesthetic and methylprednisolone is significantly more effective in preventing PHN at 12 months compared to intravenous acyclovir and prednisolone.

Unilateral postherpetic neuralgia is associated with bilateral sensory neuron damage

Shingles can cause chronic neuropathic pain (postherpetic neuralgia) long after skin lesions heal. To investigate its causes, we quantitated immunolabeled sensory neurites in skin biopsies from 18 subjects with and 16 subjects without postherpetic neuralgia after unilateral shingles. Subjects rated the intensity of their pain. Punch skin biopsies were evaluated from the site of maximum pain or shingles involvement, the homologous contralateral location, and a site on the back, distant from shingles involvement. Sections were immunostained with anti-PGP9.5 antibody, a pan-axonal marker, and the density of epidermal and dermal neurites determined. The group with postherpetic neuralgia had a mean density of 339 +/- 97 neurites/mm2 in shingles-affected epidermis compared with a density of 1,661 +/- 262 neurites/mm2 for subjects without pain. Neurite loss was more severe in epidermis than dermis. Unexpectedly, the group with pain had also lost half of the neurites in contralateral epidermis. Contralateral damage occurred despite the lack of contralateral shingles eruptions or pain, correlated with the presence and severity of ongoing pain at the shingles site, and did not extend to the distant site. Thus, the pathophysiology of postherpetic neuralgia pain may involve a new bilateral mechanism.

Lidocaine patch: double-blind controlled study of a new treatment method for post-herpetic neuralgia

Post-herpetic neuralgia (PHN) is a common and often intractable neuropathic pain syndrome predominantly affecting the elderly. Topical local anesthetics have shown promise in both uncontrolled and controlled studies. Thirty-five subjects with established PHN affecting the torso or extremities completed a four-session, random order, double-blind, vehicle-controlled study of the analgesic effects of topically applied 5% lidocaine in the form of a non-woven polyethylene adhesive patch. All subjects had allodynia on examination. Up to 3 patches, covering a maximum of 420 cm2, were applied to cover the area of greatest pain as fully as possible. Lidocaine containing patches were applied in two of the four 12-h-long sessions, in one session vehicle patches were applied, and one session was a no-treatment observation session. Lidocaine containing patches significantly reduced pain intensity at all time points 30 min to 12 h compared to no-treatment observation, and at all time points 4--12 h compared to vehicle patches. Lidocaine patches were superior to both no-treatment observation and vehicle patches in averaged category pain relief scores. The highest blood lidocaine level measured was 0.1 micrograms/ml, indicating minimal systemic absorption of lidocaine. Patch application was without systemic side effect and well tolerated when applied on allodynic skin for 12 h. This study demonstrates that topical 5% lidocaine in patch form is easy to use and relieves post-herpetic neuralgia.

Partial purification and characterization of a 235,000M(r) extracellular proteinase from Trichophyton rubrum

An extracellular proteinase has been partially purified from culture filtrates of Trichophyton rubrum by ultrafiltration, isoelectric focusing and gel filtration chromatography. The enzyme has a non-reduced molecular weight of 235,000 by substrate SDS-PAGE. It has a pH optimum of 8.5 using azocasein and azoalbumin as substrates and a pI of 3.6-3.8. The metalloproteinase inhibitors EDTA and 1,10-phenanthroline, together with the chymotrypsin inhibitor chymostatin, strongly inhibited its activity. The serine proteinase inhibitors phenylmethanesulphonyl fluoride and diisopropylfluorophosphate showed weak inhibitory activity. The proteinase exhibited broad substrate activity against azocoll, azoalbumin, azocasein, laminin and fibronectin. It exhibited weak activity against elastin and keratin. Observations on the occurrence of this proteinase together with previously described lower molecular weight proteinases suggests that the former is the first to appear in minimal medium cultures. Freeze/thaw cycling of the partially purified 235,000 M(r) proteinase was found to generate low molecular weight proteinases, particularly at 53,000, 27,000 and 25,000 M(r), indicating that the latter may originate from the larger molecule.

Herpes zoster: a comparative study of general practitioner and patient experience

A study was carried out to compare attitudes, perceptions and experiences of general practitioners and patients who had treated/suffered from herpes zoster, or shingles, in the recent past. Randomized samples of 224 general practitioners and 236 patients were drawn from different locations in Italy, Germany and the United Kingdom, and interviews were undertaken as semi-structured face-to-face discussions with the subjects. Most of the discussion questions were the same for both samples but specifically targeted either towards the professional or the patient group. Analysis of the findings showed that although there was a high level of correlation between the two groups on opinions and attitudes on a number of issues, there were significant, important differences on others. For example, prodromal symptoms acknowledged by patients were not always recognized by general practitioners and there appeared to be an inability of some to diagnose early enough to take advantage of appropriate anti-viral therapy whilst they acknowledged the need to do so. This in turn led to a number of patients either not receiving specific therapy or having inadequate therapy. Similarly, whilst general practitioners mainly reflected the current medical view that shingles is a benign and self-limiting condition, patients tended to consider shingles and post-herpetic neuralgia as a painful and serious condition that adversely affected their quality of life and to a greater extent than appreciated by many doctors. The findings of the survey indicate that there is need for improved understanding of the disease and its effects by both doctors and patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Some biochemical characteristics of a partially purified extracellular keratinase from Trichophyton schoenleinii

A Trichophyton schoenleinii (T. schoenleinii) strain from tinea favus was cultured in a liquid medium, from which an extracellular keratinase extract was obtained. The keratinase was partially purified with carboxymethyl-cellulose (CMC) column chromatography. Some biochemical characteristics of the keratinase were then examined. Its molecular weight was estimated to be 38,000 on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimal temperature was 50 degrees C, and the optimal pH value was 5.5. The keratinolytic activity was specifically increased by Fe++ and Fe .

Topical 0.025% capsaicin in chronic post-herpetic neuralgia: efficacy, predictors of response and long-term course

In order to evaluate the efficacy, time-course of action and predictors of response to topical capsaicin, 39 patients with chronic post-herpetic neuralgia (PHN), median duration 24 months, were treated with 0.025% capsaicin cream for 8 weeks. During therapy the patients rated their pain on a visual analogue scale (VAS) and a verbal outcome scale. A follow-up investigation was performed 10-12 months after study onset on the patients who had improved. Nineteen patients (48.7%) substantially improved after the 8-week trial; 5 (12.8%) discontinued therapy due to side-effects such as intolerable capsaicin-induced burning sensations (4) or mastitis (1); 15 (38.5%) reported no benefit. The decrease in VAS ratings was significant after 2 weeks of continuous application. Of the responders 72.2% were still improved at the follow-up; only one-third of them had continued application irregularly. Treatment effect was not dependent on patient's age, duration or localization of PHN (trigeminal involvement was excluded), sensory disturbance or pain character. Treatment response was not correlated with the incidence, time-course or severity of capsaicin-induced burning. If confirmed in controlled trials, the long-term results of this open, non-randomized study might indicate that the analgesic effect of capsaicin in PHN is mediated by both interference with neuropeptide metabolism and morphological changes (perhaps degeneration) of nociceptive afferents.

Alphaherpesvirus saimiri infection in rabbits. 1. Light and electron microscopy study of cutaneous spinal nerves

A light and electron microscopic study was undertaken to determine pathological changes in cutaneous spinal nerves of rabbits following intradermal inoculation with alphaherpesvirus saimiri (alpha HVS) isolate KM 322. Infected rabbits were killed at 3, 10, 17, 45 days and 2 years after infection. No abnormalities were seen at 3 days postinoculation. In the nerves of the rabbits killed at 10, 17 and 45 days after infection, axonal (Wallerian-type) degeneration was the main pathological feature. Regeneration, manifested by axonal sprouting, was observed in the nerves of the rabbits killed at 45 days post-inoculation. Neural fibrosis and paucity of unmyelinated axons was the final outcome. The severity of the neural damage not only varied according to the progression of the disease but between nerves taken from the same rabbit. This was probably associated with variation in the numbers of virus particles that had reached the dorsal root ganglion of the dermatome served by a particular nerve. Since alpha HVS (isolate KM 322) provides a model system for the study of virus latency in dorsal root ganglia, and consequently for the study of varicellazoster infection in man, these findings give further insight into the pathology of herpetic neuropathy.

Topical lidocaine reduces pain in post-herpetic neuralgia

We report the results of a single session, non-blinded, trial of topical application of 10% lidocaine in gel form to the painful skin of 11 patients with well established post-herpetic neuralgia (PHN). Pain decreased as measured by 100 mm VAS pain scale and 100 mm VAS pain relief scale in both trigeminal and thoracic PHN patients.

Human infection with herpes zoster: etiology, pathophysiology, diagnosis, clinical course, and treatment

Herpes zoster is a cutaneous vesicular eruption resulting from recrudescence of the chickenpox virus. It is mainly a disease of adults, with a predisposition for the elderly or immunocompromised. Although usually localized, the disease can disseminate to visceral organs. Diagnosis is often made based on the characteristic pattern of the lesion and clinical features. Tzanck smear, viral isolation, seroconversion, antibody titers, and monoclonal antibodies may further aid or confirm the diagnosis. Clinical features of herpes zoster may follow a progression through 3 stages, prodromal, acute, and chronic. The prodromal and acute phases seldom require more than symptomatic management. The chronic pain syndrome, postherpetic neuralgia (PHN), demands a more aggressive approach. Pharmacologic intervention, neuroaugmentation, and/or surgery may prevent or alleviate PHN, but universal response to any of these therapeutic approaches is unlikely. Tricyclic antidepressants remain the first choice in treating this pain syndrome. A trial of antiviral therapy may be warranted in patients with disseminated disease or in immunocompromised patients with localized disease. Of the antiviral agents, acyclovir is considered the drug of choice by most clinicians.

Acute herpetic and postherpetic neuralgia: clinical review and current management

The pain of acute herpes zoster (HZ) may be severe, but it is usually transitory. A minority of patients, with the elderly at particular risk, go on to develop persistent, severe, often disabling pain called postherpetic neuralgia. Though the clinical features of these conditions are well known, the pathology of PHN is poorly described and the pathogenesis of the pain in both remains conjectural. During the past 60 years, an extraordinary number of pharmacological, anesthetic, and surgical therapies have been applied in an attempt to ameliorate the symptoms of acute herpes zoster, enhance its healing, prevent its transition to postherpetic neuralgia, and treat the pain of those with this complication. Relatively few treatments have been studied in a controlled manner, and fully reliable, safe, and effective therapeutic approaches for preventing and treating postherpetic neuralgia have not yet been found. This review summarizes current information on the epidemiology, clinical features, and pathology of herpes zoster and postherpetic neuralgia, and critically examines the accumulated experience with the various treatments. Guidelines for management are suggested.

Alveolar bone necrosis and tooth loss. a rare complication associated with herpes zoster infection of the fifth cranial nerve

Eleven case reports involving herpes zoster infection associated with alveolar bone necrosis and tooth loss were reviewed in order to develop a patient profile for this rare combination of physical findings. The clinical course of a 56-year-old white woman with herpes zoster infection of the fifth cranial nerve and related alveolar bone necrosis, tooth loss, and oroantral fistula development is reported. The etiology and management of herpes zoster infection associated with destructive oral sequelae are discussed.

Effect of undecanoic acid on the production of exocellular lipolytic and keratinolytic enzymes by undecanoic acid-sensitive and -resistant strains of Trichophyton rubrum

Effects of undecanoic acid on exocellular lipase, phospholipase A and keratinase activities of wild type undecanoic acid-sensitive (udas) and an undecanoic acid-resistant mutant (udar) of Trichophyton rubrum (derived from the udas strain) were determined. Undecanoic acid inhibited the production of exocellular lipase and keratinase but stimulated the production of exocellular phospholipase A in T. rubrum udas. Undecanoic acid did not affect exocellular lipase production by T. rubrum udar. Lipase production by the udar mutant was lower than that of the udas parent. No exocellular keratinase could be detected in the udar strain which had very low capacity for invasion of keratinized tissue.

Control of exocellular proteases in dermatophytes and especially Trichophyton rubrum

The production of proteases was investigated during growth of dermatophytic fungi with special emphasis on Trichophyton rubrum. Exogenous glucose suppressed elastase production in all dermatophytes examined. The production of protease active guinea pig hair in keratin-salts broth by Microsporum gypseum. Trichophyton mentagrophytes and T. rubrum was also suppressed by glucose. Various carbohydrates added to keratin-salts broth curtailed protease production by T. rubrum as did individual amino acids but ammonium phosphate did not. Enzyme activities against guinea pig hair were compared in twenty-one diverse clinical isolates of T. rubrum cultured in keratin-salts broth. Activity also occurred towards casein, bovine serum albumin, keratin, collagen and elastin after keratin-growth. Studies concerning the properties of enzyme activities in culture filtrates of T. rubrum after keratin-growth suggested that multiple proteases occurred here. Hydrolysis of guinea pig hair and elastin were optimal at pH7 while keratinase was most active at alkaline pH. Divalent cations stimulated protease(s). Ferric ion and mercuric ion stimulated keratinase but were inhibitory to guinea pig hair hydrolysis and elastase. Chelating agents inhibited elastase and the hydrolysis of guinea pig hair more severely than keratinase and all of those effects were reversed by excess calcium. A serine-protease inhibitor, phenylmethylsulfonylfluoride (PMSF), curtailed keratinase but was less inhibitory to elastase and guinea pig hair hydrolysis. Soybean trypsin inhibitor arrested each protease.

Treatment of zoster and postzoster neuralgia by the intralesional injection of triamcinolone: a computer analysis of 199 cases

On the basis of this study of 111 patients with herpes zoster and 88 with postherpetic neuralgia, it is suggested that the intradermal injection of triamcinolone in saline is a valuable treatment. Mild complications were pain, hemorrhage, abscesses, atrophy, moon face and possibly thrombophlebitis. Zoster patients required treatment for about half as long as those in previously reported control series. In patients treated for active herpes zoster, postzoster neuralgia occurred with about one-third of the frequency noted in other series. In postzoster neuralgia, the patient was benefited sufficiently in 62.5% of the cases to find that life was worth living again.