Febrile ulceronecrotic Mucha-Habermann disease - a case and treatment review.

Febrile ulceronecrotic Mucha-Habermann disease is a rare and severe variant of pityriasis lichenoides, characterized by sudden onset of generalized ulceronecrotic papules that rapidly coalesce into ulcers associated with high fever. Systemic manifestations such as intravascular disseminated coagulation and pulmonary, cardiac, gastrointestinal, and central nervous system involvement are common. Treatment is based on oral corticosteroids, immunosuppressive drugs such as methotrexate, and general supportive treatment. The present case describes a stepwise approach to a patient with Mucha-Habermann disease with insufficient response to methotrexate.

Utility of IL-36 immunostaining in distinguishing psoriasis from pityriasis rosea and pityriasis lichenoides.

BACKGROUND: Psoriasis is an inflammatory skin disease driven by upregulation of cytokines in the Th17 pathway, including interleukin-36 (IL-36). Previous studies have highlighted the utility of IL-36 immunostaining for psoriasis compared to spongiotic dermatitis and other psoriasiform dermatoses; however, no study has examined the role of IL-36 staining in distinguishing psoriasis from pityriasis rosea (PR) and pityriasis lichenoides (PL), known histologic mimickers of psoriasis. METHODS: We compared the immunostaining pattern of IL-36 for 21 PR cases, 22 PL cases, and 10 psoriasis cases. We graded the immunostaining as 0, negative; 1, focal weak; 2, diffuse weak; 3, focal, strong; or 4, diffuse strong. We further categorized stains as negative (0-2 score) or positive (3-4 score) and utilized Fisher's exact test to compare the immunostaining pattern of these entities. RESULTS: All psoriasis specimens were positive for IL-36, whereas all PR specimens were negative (p = 0.00000002). Twenty PL specimens were negative (p = 0.000001). Nine of 10 pityriasis lichenoides et varioliformis acuta cases were negative (p = 0.00012), and 11 of 12 cases of pityriasis lichenoides chronica were negative (p = 0.00003). CONCLUSIONS: Our findings highlight the potential role of IL-36 immunostaining in distinguishing psoriasis from other psoriasiform dermatoses, including PR and PL.

What is pityriasis lichenoides?

Pityriasis lichenoides (PL) is an uncommon skin rash. PL has two main forms: Pityriasis lichenoides et varioliformis acuta (PLEVA): this "acute" (fast) form comes on quickly. Pityriasis lichenoides chronica (PLC): this "chronic" (long) form often develops slowly and lasts longer.

Paediatric-onset lymphomatoid papulosis: results of a multicentre retrospective cohort study on behalf of the EORTC Cutaneous Lymphoma Tumours Group (CLTG).

BACKGROUND: Lymphomatoid papulosis (LyP) is a rare cutaneous T-cell lymphoproliferative disorder. Comprehensive data on LyP in the paediatric population are scarce. OBJECTIVES: To characterize the epidemiological, clinical, histopathological and prognostic features of paediatric LyP. METHODS: This was a retrospective multicentre international cohort study that included 87 children and adolescents with LyP diagnosed between 1998 and 2022. Patients aged ≤ 18 years at disease onset were included. LyP diagnosis was made in each centre, based on clinicopathological correlation. RESULTS: Eighty-seven patients from 12 centres were included. Mean age at disease onset was 7.0 years (range 3 months-18 years) with a male to female ratio of 2 : 1. Mean time between the onset of the first cutaneous lesions and diagnosis was 1.3 years (range 0-14). Initial misdiagnosis concerned 26% of patients. LyP was most often misdiagnosed as pityriasis lichenoides et varioliformis acuta, insect bites or mollusca contagiosa. Erythematous papules or papulonodules were the most frequent clinical presentation. Pruritus was specifically mentioned in 21% of patients. The main histological subtype was type A in 55% of cases. When analysed, monoclonal T-cell receptor rearrangement was found in 77% of skin biopsies. The overall survival rate was 100%, with follow-up at 5 years available for 33 patients and at 15 years for 8 patients. Associated haematological malignancy (HM) occurred in 10% of cases (n = 7/73), including four patients with mycosis fungoides, one with primary cutaneous anaplastic large cell lymphoma (ALCL), one with systemic ALCL and one with acute myeloid leukaemia. If we compared incidence rates of cancer with the world population aged 0-19 years from 2001 to 2010, we estimated a significantly higher risk of associated malignancy in general, occurring before the age of 19 years (incidence rate ratio 87.49, 95% confidence interval 86.01-88.99). CONCLUSIONS: We report epidemiological data from a large international cohort of children and adolescents with LyP. Overall, the disease prognosis is good, with excellent survival rates for all patients. Owing to an increased risk of associated HM, long-term follow-up should be recommended for patients with LyP.

Lymphomatoid papulosis is a very rare skin condition caused by an abnormal increase in white blood cells (called 'lymphocytes') in the skin. The condition rarely affects children, so most of the scientific data published about this disease focuses on adults. This study involved 12 academic dermatology centres in Europe, the Middle East and North America, and gathered data from about 87 children who presented with symptoms of lymphomatoid papulosis before the age of 19 years. The aim of this study was to better describe this disease in the paediatric population and discuss its treatment options and evolution. We found that the presentation of the disease in children is roughly the same as in adults. Safe and effective treatment options exist. The disease is not life threatening, but it requires investigation by a dermatologist, both to make a careful diagnosis and to monitor it as sometimes associated cancers that originate from blood cells can occur, mostly on the skin.

Efficacy and safety of excimer light (308 nm) in the treatment of pityriasis lichenoides chronica.

INTRODUCTION: Pityriasis lichenoides chronica is the chronic end of the spectrum of pityriasis lichenoides which have several forms of papulosuamous conditions. Several treatments obtained complete clearance of the condition including phototherapy and specifically narrow band ultraviolet B. The Excimer light 308 is a monochromatic light that acts within the ultraviolet B wavelength and used as a targeted phototherapy in several skin conditions. METHODS: Thirty-four patients with histopathologically diagnosed pityriasis lichenoides chronica underwent treatment with biweekly sessions of excimer light 308 nm. Treatment continued until complete clearance was obtained or to a maximum of 48 sessions (24 weeks). RESULTS: Thirty-one patients obtained complete clearance with no recurrence till the end of the study period, two patients had partial response and only one patient showed poor response to treatment. CONCLUSION: Excimer light can be a safe and effective treatment of pityriasis lichinoides chronica in different ages and genders.

Pityriasis lichenoides: assessment of 41 pediatric patients.

OBJECTIVES: This study aims to evaluate the characteristics and treatment response of patients with pityriasis lichenoides seen in the last 43 years in a pediatric dermatology service. METHODS: This was a retrospective, analytical, longitudinal study of patients under 15 years of age. The medical records were reviewed and data were presented as frequencies, means and variances. Student's t-test, Mann-Whitney test, Fisher's exact test, Pearson/Yates chi-square test and multivariate logistic regression model were used, with p < 0.05 considered. RESULTS: 41 patients were included, 32 (78.0%) with pityriasis lichenoides chronica (PLC), five (12.2%) with pityriasis lichenoides et varioliformis acuta (PLEVA) and four (9.8%) with clinical PLC without biopsy. The age range of school children and adolescents was 19 (46.3%) and 13 (31.7%) respectively and 27 (65.8%) were male. Two peaks of the highest frequency were observed between 2004 and 2006 (10 patients - 24.4%) and another between 2019 and 2021 (6 patients - 14.7%). There was remission in 71.9% (n = 23), with 56.6% (n = 17) of those who used antibiotic therapy and 80% (n = 4) of those who had phototherapy. The chance of remission was 13 times greater in patients with disease onset after 5 years of age. CONCLUSIONS: The clinical form most commonly found was PLC mainly in school children and adolescents. The frequency peaks coincided with infectious outbreaks. The remission rate was satisfactory with antibiotic therapy, but higher with phototherapy. Remission was greater in patients with disease onset after 5 years of age.

Febrile Ulceronecrotic Mucha-Habermann Disease Associated With Hemophagocytic Lymphohistiocytosis: A Case Report and Review of the Literature.

ABSTRACT: Mucha-Habermann disease (MHD) is an inflammatory skin disease characterized by polymorphous eruptions of erythematous, necrotic macules that have been reported for similarities to cutaneous T-cell lymphoma. Febrile ulceronecrotic MHD (FUMHD) represents a severe variant of MHD, marked by ulcers, hemorrhagic bullae, and systemic symptoms. Herein, we report a case of a severely atypical lymphomatoid expression of FUMHD associated with hemophagocytic lymphohistiocytosis (HLH). A previously healthy 21-year-old woman was admitted to the hospital with a rapidly progressive necrotic papular rash. Physical examination revealed right orbital swelling, bilateral hemorrhagic auricular bullae, and multiple ulcerative purpuric papulonodules on the trunk, face, and extremities. Biopsy indicated a dermal and subcutaneous infiltrate of atypical CD8 + lymphocytes with loss of CD5 and reduction in CD7 expression, along with features of lymphomatoid vasculitis. A diagnosis of a severely atypical lymphomatoid expression of FUMHD was made. The patient also met 7 of 9 HLH-2004 criteria, leading to a diagnosis of HLH. Positron emission tomography/computed tomography, flow cytometry, and rheumatologic workup were unremarkable. Treatment with an eight-week course of etoposide and dexamethasone for HLH led to rapid clinical improvement. Over time, her skin lesions regressed and eventually scabbed over to leave hyperpigmented scars, confirming the diagnosis of MHD. She has remained stable, off therapy for 4 years. Although potentially fatal, FUMHD often exhibits favorable outcomes and may resolve without recurrence, as in our patient. FUMHD should be considered in the differential diagnosis for patients presenting with cutaneous CD8 + necrotizing angiocentric lymphoproliferative disease complicated by HLH.

Atypical plaque psoriasis: a clinicopathological study of 20 cases.

BACKGROUND: Plaque psoriasis is relatively straightforward to identify. When diagnostic concerns arise in atypical cases, a biopsy is needed. It is widely accepted that the Munro microabscess and the spongiform pustule of Kogoj are diagnostic pathological features. However, the diagnostic dilemma is likely to arise in cases without these specific pathological changes and typical clinical features. This study aimed to investigate clinical and pathological clues in distinguishing atypical plaque psoriasis from its mimics. METHODS: We evaluated the clinicopathological features of 20 cases of atypical plaque psoriasis and 40 cases of psoriasis mimics as controls including pityriasis rosea (n = 10), pityriasis lichenoides chronica (n = 8), and subacute dermatitis (n = 22). RESULTS: A retrospective analysis of the clinicopathological characteristics of patients with atypical plaque psoriasis and controls was performed. Pathologically, there were significant differences between the two groups in the types of parakeratosis (P = 0.046), epidermal capture of extravasated erythrocytes (P = 0.011), focal basal liquefied degeneration (P = 0.017), types of inflammatory cells (P = 0.000), and depth of inflammation (P = 0.000). Clinically, we found the presence of scales and crusts was significantly different between the two groups. CONCLUSION: This study offers insight into the clinicopathological features of atypical plaque psoriasis. These differential diagnostic features, compared with its mimics, are proposed to assist the clinician in the diagnosis and treatment of atypical plaque psoriasis.

Rapid recovery in a child with febrile ulceronecrotic Mucha-Habermann disease following intravenous immunoglobulin administration.

Febrile ulceronecrotic Mucha-Habermann disease (FUMHD), a lymphocyte-mediated inflammatory skin disorder, is considered a severe variant of pityriasis lichenoides et varioliformis acuta that can lead to a fatal outcome if not managed in a timely fashion. Children with FUMHD can have systemic complications involving various organs. The scarcity of reported cases and the absence of well-designed studies or randomized clinical trials to evaluate different therapeutic modalities pose a major challenge in treating this potentially life-threatening disorder. We report a five-year-old child with FUMHD and seizures treated unsuccessfully with a combination of systemic steroids, methotrexate, dapsone, and oral erythromycin, who improved rapidly and achieved disease control with just a single infusion of low-dose intravenous immunoglobulin.

Dermoscopy as a diagnostic aid in pityriasis lichenoides et varioliformis acuta.

Diagnosis of pityriasis lichenoides et varioliformis acuta (PLEVA) is based on the characteristic pattern of lesions in different stages of development, ranging from erythematous maculopapules to papules with a crusted and/or necrotic centre. However, it may raise the differential diagnosis with other entities. It is therefore not uncommon to have to perform skin biopsies to reach a diagnosis, including in infants. In this study, we report the cases of three patients with PLEVA, highlighting the correlations between the clinical, dermoscopic and histological features. Observation of the dermatoscopic findings described, such as punctate or glomerular vessels and erythematous globules surrounding a homogeneous orange or crusty central area, may allow for a rapid diagnosis, avoiding the need for invasive techniques.

Narrowband ultraviolet B phototherapy for pityriasis lichenoides: A real-life experience.

INTRODUCTION: Pityriasis lichenoides (PL) is a papulosquamous disease affecting both children and adults, for which narrowband-UVB (NB-UVB) phototherapy is regarded as a commonly used treatment option. The aim of this study was to investigate the efficacy of NB-UVB phototherapy in the management of PL and to compare response rates in pediatric and adult age groups. MATERIALS AND METHODS: This observational, retrospective study included 20 PL patients (12 pityriasis lichenoides chronica; PLC, 8 pityriasis lichenoides et varioliformis acuta; PLEVA) who failed to respond to other treatment modalities. The data for this study were collected retrospectively from patient follow-up forms in the phototherapy unit. RESULTS: A complete response (CR) was obtained in all pediatric patients with PL, while 53.8% of adult patients had achieved CR. The mean cumulative dose required to achieve the CR was higher in pediatric patients than adult patients with PL (p < .05). The CR was achieved in 6 (75%) of 8 PLEVA patients, while 8 (66.7%) of 12 PLC patients had reached to CR. The mean number of exposures for patients with PLC to achieve a CR was higher than patients with PLEVA (p < .05). Erythema was the most common adverse effect during phototherapy particularly in 5 (35.7%) of the patients with PL who had achieved CR. CONCLUSIONS: NB-UVB is an effective and well-tolerated treatment option for PL especially in diffuse types. A higher response can be obtained in children with higher cumulative dose. Patients with PLC may require more exposures for CR than patients with PLEVA.

Acute lichenoid and varioliform pityriasis in a pediatric patient.

BACKGROUND: Pityriasis lichenoides et varioliformis acuta (PLEVA) is a rare dermatosis recognized as a benign condition of unknown etiopathogenesis. It is more common in pediatric patients and young adults and is characterized by multiple small or large erythematous plaques spread over the trunk and extremities. CASE REPORT: We describe the case of a 5-year-old male, previously healthy, with multiple erythematous lesions that disappeared leaving hypopigmented macules. The biopsy reported histological changes suggestive of mycosis fungoides. After a second revision of lamellae in this hospital, lymphocytic vasculitis (LV) with focal epidermal necrosis consistent with acute pityriasis lichenoides (PL) was identified. CONCLUSIONS: The existing knowledge about PLEVA lacks a consensus in specifying its classification, etiopathogenesis, diagnosis, and treatment, so this clinical condition represents a medical challenge. The diagnosis is made by clinical suspicion and confirmed by histology. The objective of this article was to report a case of PLEVA with an atypical presentation due to its histopathological findings, being the first report showing LV in children, as well as a review of the literature.

INTRODUCCIÓN: La pitiriasis liquenoide y varioliforme aguda (PLEVA) es una dermatosis poco frecuente, de etiopatogenia desconocida y evolución autolimitada. Es más común en pacientes pediátricos y adultos jóvenes, y está caracterizada por la presencia de múltiples placas eritematoescamosas pequeñas o grandes, diseminadas en el tronco y las extremidades. CASO CLÍNICO: Se describe el caso de un escolar de 5 años, de sexo masculino, previamente sano, que presentó múltiples cuadros de lesiones eritematosas que desaparecían dejando máculas hipopigmentadas. La biopsia reportó cambios histológicos sugestivos de micosis fungoide. Se realizó una segunda revisión de laminillas, identificando vasculitis linfocítica con necrosis epidérmica focal, consistente con pitiriasis liquenoide aguda. CONCLUSIONES: El conocimiento acerca de la PLEVA carece de un consenso que especifique su clasificación, etiopatogenia, diagnóstico y tratamiento, por lo que esta condición clínica representa un desafío médico. El diagnóstico se realiza por sospecha clínica y se confirma por histología. El objetivo de este artículo fue reportar un caso de PLEVA con presentación atípica por los hallazgos histopatológicos, siendo este el primer reporte de vasculitis linfocítica en niños, y además se realiza una revisión de la literatura.

Febrile ulceronecrotic Mucha-Habermann disease during pregnancy: A case report.

Febrile ulceronecrotic Mucha-Habermann disease (FUMHD) is a rare and severe form of 'pityriasis lichenoides et varioliformis acuta', with a progressive and potentially fatal course. To the best of our knowledge, there has been no reported case of FUMDH during pregnancy before. Due to life-threatening nature of the disease and the lack of evidence-based treatment, management of FUMHD in pregnancy is a therapeutic challenge. Additionally, some of the drugs that are effective in the treatment are contraindicated in pregnancy. Herein, we report a 27-year-old woman diagnosed with FUMHD in her 19th week of pregnancy and treated with ceftriaxone and erythromycin.

Febrile Ulceronecrotic Mucha-Habermann Disease: A Case Report and Review of Literature in the Paediatric Population.

Febrile ulceronecrotic Mucha-Habermann disease (FUMHD) is a rare fulminant variant of pityriasis lichenoides et varioliformis acuta (PLEVA) that is characterized by a large ulceronecrotic appearance with high fever and a variety of systemic symptoms. We report here a case of FUMHD in a 17-year-old male Chinese patient who was treated successfully with a combination therapy of methotrexate, methylprednisolone, and intravenous immunoglobulin. In addition, a literature review was conducted to summarize the key characteristics of paediatric FUMHD cases.

A case of febrile ulceronecrotic Mucha-Habermann disease responsive to systemic corticosteroids.

Febrile ulceronecrotic Mucha-Habermann disease (FUMHD) is a rare, potentially fatal subtype of pityriasis lichenoides et varioliformis acuta (PLEVA). Herein, we present a rare case of a 14-year-old male without significant past medical history who was diagnosed with FUMHD without a clear inciting factor. He was effectively treated with systemic corticosteroids with complete resolution of symptoms.

The role of NLRP1 and NLRP3 inflammasomes in the etiopathogeneses of pityriasis lichenoides chronica and mycosis fungoides: an immunohistochemical study.

Mycosis fungoides (MF) is the most common subtype of primary cutaneous T cell lymphomas, whereas pityriasis lichenoides chronica (PLC) is a chronic inflammatory skin disorder. The inflammasome is a part of the natural immune system which has a multimeric structure consisting of the receptor, adaptor and effector protein that show specificity for various ligands or activators. After the activation of the inflammasome complex, caspase 1 becomes activated which subsequently triggers interleukin-18 (IL-18) and interleukin-1ß (IL-1ß) production. In our study we aimed to examine the roles of nucleotide-binding oligomerization domain-like receptor containing pyrin domain 1 (NLRP1) and nucleotide-binding oligomerization domain-like receptor containing pyrin domain (NLRP3) inflammasomes in the etiopathogeneses of PLC and MF. NLRP1, NLRP3, caspase 1, IL-18 and IL-1ß levels were examined and compared immunohistochemically in the skin biopsies belonging to 16 control patients; 16 PLC cases, 12 cases with stage 1 MF and 12 cases with other stages of MF (stage 2-4). In the paired comparisons of NLRP1, stage 2-4 MF group and PLC group were shown to have increased levels of NLRP1 expression compared to the control group. IL-1ß was also expressed at statistically significantly higher levels in each of the stage 1 MF, stage 2-4 MF and PLC groups compared to the control group. In the paired comparisons of caspase 1 and IL-18, it was found that stage 1 MF, stage 2-4 MF and PLC groups had increased levels of expression compared to the control group. Our findings suggest that the NLRP1 inflammasome pathway might play a role in the etiopathogenesis and progression of PLC and MF.