Varicella zoster virus as a possible trigger for the development of pityriasis lichenoides et varioliformis acuta: retrospective analysis of our institutional cases.

Although numerous infective agents, including varicella zoster virus (VZV), have been described in association with pityriasis lichenoides et varioliformis acuta (PLEVA) and pityriasis lichenoides chronica (PLC), none has been identified consistently in these lesions. We sought to immunohistochemically identify VZV glycoprotein (g)E antigens in the vascular endothelium in PLEVA and PLC lesions, based on our previous observation that gE was detected in the vascular endothelium and eccrine unit up until 2 months and 2.5, respectively, years after herpes zoster (HZ) infection. In five of the six cases of PLEVA, VZV gE was identified in the endothelial cells and eccrine epithelium, as observed in HZ lesions, whereas VZV gE was detected in only one of seven patients with PLC. None of the patients with PLEVA who had VZV gE-positive vascular endothelial cells had experienced previous episodes of HZ. VZV may be one of the aetiological agents for PLEVA while other aetiological factors could exist in PLC.

Pitiryasis Lichenoides et Varioliformis Aacuta Associated With Human Herpesvirus 7. / Pitiriasis liquenoide y varioliforme aguda asociada al virus herpes humano tipo 7.

Pityriasis lichenoides et varioliformis acuta and pityriasis lichenoides chronica represent 2 ends of a disease spectrum of unknown etiology. Herein we describe 2 cases of pityriasis lichenoides et varioliformis acuta, in which human herpesvirus 7 DNA was detected in skin samples by polymerase chain reaction methodology, an association not previously described. This report may support the involvement of viral infection in the etiopathogeny of this disease.

Paraviral exanthems.

INTRODUCTION: Paraviral exanthems are skin diseases suspected to be caused by viruses, with a single virus-exanthem relationship not universally accepted. Although most paraviral exanthems are self-remitting, accurate diagnoses are important as some patients might develop complications. Some of the differential diagnoses might cause serious complications, and some paraviral exanthems might lead to complications for at-risk groups such as pregnant women. Moreover, some paraviral exanthems might be symptomatic such as the development of severe pruritus, with relief of such being crucial in the plan of management. Patients and carers of patients should also be counselled regarding the aetiologies, clinical features, and prognoses of the exanthems concerned. AREAS COVERED: We covered the clinical manifestations and managements of pityriasis rosea, pityriasis lichenoides, and Gianotti-Crosti syndrome. Expert Commentary: Most patients with pityriasis rosea do not need any active intervention. Symptomatic relief of the pruritus would be adequate. For patients with pityriasis rosea that are serious, extensive, or causing severe impacts of their quality of life, oral acyclovir could be considered. For pityriasis lichenoides, managements would be depending on the type of the exanthem such as the acute form (pityriasis lichenoides et varioliformis acuta, also known as Mucha Habermann disease) the chronic form (pityriasis lichenoides chronic Juliusberg's disease), and the febrile ulceronecrotic Mucha-Habermann disease, which is a complication of the acute form. The management of Gianotti-Crosti syndrome is mainly symptomatic. The need for long-term follow-up for chronic complications of the underlying viral infections is still controversial.

Varicella-zoster virus as a possible cause of pityriasis lichenoides et varioliformis acuta.

The etiologic agents for pityriasis lichenoides et varioliformis acuta (PLEVA) are largely unknown, although it has been suggested that foreign antigens such as infectious agents are the pathogenic mechanism. We present a case suggesting a possible relationship between varicella-zoster virus and PLEVA.

Febrile ulceronecrotic Mucha-Habermann disease (pityriasis lichenoides et varioliformis acuta fulminans) associated with parvovirus infection.

Febrile ulceronecrotic Mucha-Habermann disease is a rare fulminant variant of pityriasis lichenoides et varioliformis acuta, characterized by a rapidly progressive course with predominant ulceronecrotic lesions associated with fever and systemic manifestations. It carries a great morbidity and is potentially fatal. The exact pathogenesis is not clear, and it has been proposed to be the result of hypersensitivity reaction to an infection. We report a patient with febrile ulceronecrotic Mucha-Habermann disease in a 12-year-old boy in whom the condition was most likely precipitated by parvovirus infection, and he showed a favorable response to a combination of prednisolone with narrow band ultraviolet B (NB-UVB) phototherapy.

Varicella precipitating febrile ulceronecrotic Mucha-Habermann disease.

We report a 9-year-old boy with skin lesions clinically and histologically compatible with pityriasis lichenoides et varioliformis acuta that evolved to the severe variant febrile ulceronecrotic Mucha-Habermann disease and finally to pityriasis lichenoides chronica. Varicella-zoster virus (VZV) was isolated in culture medium from the skin lesions and serum serology was positive for VZV. This is the first time that a virus has been isolated in culture in this condition.

Pityriasis lichenoides et varioliformis acuta with numerous CD30(+) cells: a variant mimicking lymphomatoid papulosis and other cutaneous lymphomas. A clinicopathologic, immunohistochemical, and molecular biological study of 13 cases.

Pityriasis lichenoides comprises a clinicopathologic spectrum of cutaneous inflammatory disorders, with the 2 most common variants being pityriasis lichenoides et varioliformis acuta (PLEVA) and pityriasis lichenoides chronica. The aim of the study was to describe 13 cases of a unique PLEVA variant characterized in the conspicuous CD30 component and thus mimicking lymphomatoid papulosis (LyP), a condition currently classified in the spectrum of CD30 lymphoproliferative disorders. The cohort included 10 female and 3 male patients whose ages at diagnosis ranged from 7 to 89 years (mean 41 y; median 39 y). The clinical manifestation was that of PLEVA, with small erythematous macules quickly evolving into necrotic papules. No waxing and waning was seen on follow-up in any of the cases. Histopathologically, typical features of PLEVA were present, but an unusual finding was occurrence of a considerable number of CD30 small lymphocytes as detected immunohistochemically. Over half of the cases also displayed a large number of CD8 cells and showed coexpression of CD8 and CD30 in the intraepidermal and dermal component of the infiltrate. Of the 11 cases of PLEVA studied for T-cell receptor gene rearrangement, 6 evidenced a monoclonal T-cell population, and 5 were polyclonal. Parvovirus B19 (PVB19) DNA was identified in 4 of 10 cases investigated, and positive serology was observed for PVB19 in 2 patients, altogether suggesting that PVB19 is pathogenetically linked to PLEVA at least in a subset of cases. The presence of CD30 lymphocytes and CD8 lymphocytes would be consistent with an inflammatory antiviral response, as CD30, even atypically appearing lymphoid cells have been identified in some viral skin diseases. The main significance of the PLEVA variant is, however, its potential confusion with LyP or some cytotoxic lymphomas. Admittedly, the CD30 PLEVA variant described herein and LyP show considerable overlap if one takes into account all known variations of the 2 conditions recognized in recent years, thus suggesting that LyP and PLEVA may be much more biologically closely related entities than currently thought or can even occur on a clinicopathologic spectrum.

Pityriasis lichenoides et varioliformis acuta and pityriasis lichenoides chronica: comparison of lesional T-cell subsets and investigation of viral associations.

BACKGROUND: Pityriasis lichenoides (PL) exhibits a broad clinical spectrum that includes both acute and chronic forms. The precise biologic mechanisms underlying PL remain unclear. OBJECTIVES: To evaluate the immunohistochemical characteristics of PL and to investigate lesional T-cell subsets and the possible role of viral infection in its pathogenesis. PATIENTS AND METHODS: Samples from 10 patients with PL et varioliformis acuta (PLEVA) and 13 with PL chronica (PLC) were analyzed immunohistochemically. Epstein-Barr virus early regions were assayed by in situ hybridization and T-cell receptor-γ (TCR-γ) gene rearrangements were assayed by polymerase chain reaction (PCR). We also utilized PCR to assay for human herpesvirus-8 (HHV-8) DNA in 51 patients with PL and in 25 controls. RESULTS: Lymphocytes expressing CD8 and T-cell intracellular antigen-1 were more abundant in patients with PLEVA than with PLC, whereas CD4+ lymphocytes and FOXP3-positive regulatory T-cells were more abundant in PLC. HHV-8 DNA was present in 11 of 51 (21.6%) PL patients and 0 of 25 controls. A clonal TCR-γ gene rearrangement was observed in only one patient with PLEVA. CONCLUSIONS: Our data suggests that PL may represent an inflammatory condition induced by various triggering agents, such as HHV-8, rather than a lymphoproliferative disorder. PLEVA, characterized by an acute course with severe symptoms, may indicate a relative lack of regulatory T-cells in comparison with PLC.

Parvovirus b19 DNA is commonly harboured in human skin.

BACKGROUND: Parvovirus B19 is the aetiological agent of erythema infectiosum. The presence of B19 DNA in lesional skin of other cutaneous manifestations has frequently been reported although there is disagreement on the role of the B19 virus in tissues. OBJECTIVES: To investigate the presence of B19 DNA (1) in skin lesions of patients with a described B19-related disease, (2) in skin lesions of B19-unrelated diseases and (3) in healthy skin. METHODS: A total of 121 skin samples were examined for the presence of B19 DNA by PCR assays and peptide-nucleic-acid-based in situ hybridisation techniques. RESULTS: B19 DNA was detected in 11/38 (28.9%) pityriasis lichenoides, 8/30 (26.7%) melanocytic naevi, 5/29 (17.2%) primary melanomas and 6/24 (25.0%) healthy skin biopsies. A difference in B19 DNA prevalence was observed in specimens grouped according to age, irrespective of pathologies. CONCLUSIONS: B19 DNA can be found in skin tissues of patients with pityriasis lichenoides as well as in lesions not related to B19 infection and in healthy controls. B19 DNA can be detected in skin of young subjects in a significantly high rate compared to adults, suggesting that viral persistence may be the usual outcome after primary infection.

Pityriasis lichenoides: a cytotoxic T-cell-mediated skin disorder. Evidence of human parvovirus B19 DNA in nine cases.

BACKGROUND: Pityriasis lichenoides et varioliformis acuta (PLEVA) and pityriasis lichenoides chronica (PLC) probably represent the polar ends of the same pathologic process, i.e. pityriasis lichenoides (PL), with intermediate forms in between. Previous studies have demonstrated that the inflammatory infiltrate in PLEVA is composed of cytotoxic suppressor T cells, whereas in PLC the helper/inducer T-cell population drives the immunological answer. Furthermore, monoclonal rearrangement of the T-cell receptor-gamma (TCR-gamma) genes was repeatedly found both in PLEVA and PLC. METHODS: Forty-one formalin-fixed, paraffin-embedded tissue specimens of 40 cases of PL were retrieved from the files of the authors. Immunophenotyping for cytotoxic granular proteins (Tia-1/GMP-17 and Granzyme B) and T-cell-related antigens (n = 41), TCR-gamma chain gene analysis (n = 30) and molecular investigations for parvovirus B19 (PVB19) DNA (n = 30) were performed. RESULTS: Overlapping immunophenotypes were observed in PLEVA and PLC. The dermal and epidermal T cells predominantly expressed CD2, CD3, CD8, and Tia-1 with a variable positivity for CD45RA, CD45RO, and Granzyme B. A monoclonal rearrangement pattern of the TCR-gamma genes was detected in three cases (10%). PVB19 DNA was found in nine cases (30%). T-cell monoclonality in conjunction with genomic PVB19 DNA was present in one case. CONCLUSIONS: Our results demonstrate that PL is a skin disorder mediated by the effector cytotoxic T-cell population. The identification of PVB19 DNA in nine cases may be interpreted ambiguously: PVB19 as a true pathogen or as an innocent bystander.

Expression of cutaneous lymphocyte-associated antigen and TIA-1 by lymphocytes in pityriasis lichenoides et varioliformis acuta and lymphomatoid papulosis: immunohistochemical study.

BACKGROUND: Pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP) are benign self-healing cutaneous eruptions that may be clinically and histologically similar. The purposes of this study were to evaluate immunohistological characteristics of PLEVA and LyP and to investigate whether Epstein-Barr virus (EBV) may be present in PLEVA and LyP. METHODS: We performed an immunohistochemical staining in 12 cases of PLEVA and 8 cases of LyP using nine antibodies for CD3, CD4, CD8, CD30, CD45RO, CD56, CD79, cutaneous lymphocyte-associated antigen (CLA), and TIA-1. In situ hybridization was performed using fluorescein-conjugated oligonucleotide probes for EBV early regions (EBER). RESULTS: In PLEVA, immunohistochemical studies revealed that infiltrated lymphocytes consisted of mainly CD3-positive (5+), CD8-positive (4+ to 5+), CLA-positive (4+ to 5+) T cells and partly CD79 positive (+ to 2+) B cells. CD4-positive T cells were less than 25%. In LyP, immunohistochemical studies revealed that infiltrated lymphocytes consisted of partly CD3-positive (5+), CD8-positive (2+ to 3+), CLA-positive (3+ to 4+) T cells and partly CD79-positive (2+ to 3+) B cells. CD4-positive T cells were less than 10%. CD8 and CLA were more strongly expressed in PLEVA than in LyP. CD30 was strongly expressed in LyP but not expressed in PLEVA. CD79 was more expressed in LyP than in PLEVA. TIA-1 was not expressed in any cases. In situ hybridization using antisense EBER probe showed negative reaction in all cases. CONCLUSIONS: Immunohistochemical stains for CD8, CD30, CD79 and CLA may be valuable tools in the differential diagnosis between PLEVA and LyP. TIA-1 was negative in LyP, which means cytotoxic cells may not be implicated in the pathogenesis of LyP. It was a contradictory result to the previous results. The absence of EBV in PLEVA and LyP suggests that this virus may not be operative in the pathogenesis of these diseases. These results suggest that LyP and PLEVA are separate disorders, thus accounting for their variable prognosis.