Neutrophilic dermatoses

Neutrophilic dermatoses (ND) are a group of inflammatory skin conditions characterized by a neutrophilic infiltrate on histopathology with no evidence of infection. ND are classified based upon the localization of neutrophils within the skin and clinical features. Recent findings suggest that ND are due to two main mechanisms: i) a polyclonal hereditary activation of the innate immune system (polygenic or monogenic); or ii) a clonal somatic activation of myeloid cells such as encountered in myelodysplastic syndrome or VEXAS syndrome. ND belong to internal medicine as a great number of patients with ND suffer from an underlying condition (such as hematological malignancy, inflammatory bowel disease, auto-immune and auto-inflammatory diseases). ND are diagnoses of exclusion and physicians should always consider differential diagnoses, particularly skin infections. Here, we review the pathophysiology and classification of the main ND (i.e., subcorneal pustular dermatosis (Sneddon-Wilkinson Disease) and Intercellular IgA dermatoses, aseptic pustulosis of the folds, Sweet syndrome, neutrophilic eccrine hidradenitis, pyoderma gangrenosum, erythema elevatum diutinum, neutrophilic urticarial dermatosis and neutrophilic panniculitis), their clinical and histopathological features, and we highlight the investigations that are useful to identify ND-associated diseases and to exclude the differential diagnoses.

Reasons for Discontinuation of dupilumab in Adult Atopic Dermatitis in Clinical Practice

Dupilumab, an anti-IL-4ɑ monoclonal antibody, has shown a positive benefit-risk ratio when treating moderate to severe atopic dermatitis (AD) in clinical studies (1). High persistence on dupilumab has recently been reported in clinical-practice setting with 77% of patients remaining in treatment for 12 months in a retrospective study including 1,963 patients with AD but reasons for discontinuation were not investigated (2).

Treatment of Eosinophilic Annular Erythema: Retrospective multicenter study and literature review

BACKGROUND

Eosinophilic annular erythema (EAE) is a rare eosinophil-related skin disease which typically manifests with annular erythematous plaques and severe pruritus. Besides the diagnosis, the treatment of EAE is challenging since relevant published data are sparse.

METHODS

The aim of this study was to assess the underlying diseases, treatments and outcomes of patients with EAE. To this end, we conducted a retrospective multicenter study and a systematic review of the MEDLINE database.

RESULTS

We included 18 patients with EAE followed in 8 centers. The MEDLINE database search yielded 37 relevant publications reporting 55 cases of EAE with 106 treatment sequences. The most common and efficient treatments included topical or systemic corticosteroids, hydroxychloroquine and dapsone. In refractory patients, a combination of systemic corticosteroids with hydroxychloroquine was associated with 88% of complete clinical response.

DISCUSSION

To improve the management of EAE patients, we discuss the following treatment strategy: in topical steroid-resistant patients, hydroxychloroquine can be given as first-line systemic treatment. Dapsone, hydroxychloroquine or systemic corticosteroids are second-line options to consider. Last, monoclonal antibodies or JAK inhibitors targeting type 2 inflammation could represent promising last-resort options in refractory patients.

Cohorte de 277 cas de lésions cutanées observées en dermatologie libérale dans le cadre de la pandémie de COVID-19

Introduction

L’infection à SARS-CoV-2 (COVID-19), pneumonie associée au virus SARS-Cov2, a été identifiée pour la première fois à Wuhan, en Chine en décembre 2019, et a été qualifiée de pandémie par l’Organisation mondiale de la santé (OMS) le 11 mars 2020.

Matériel et méthodes

Nous avons réalisé une étude rétrospective observationnelle à l’échelle nationale des lésions cutanées rencontrées lors de la pandémie de COVID-19 en France du 18 mars au 9 avril 2020 dans un cadre ambulatoire. Les patients ont donné leur consentement éclairé pour la publication de leurs photographies et cette étude a été approuvée par le CPP de l’hôpital Bichat, Paris.

Observations

Deux cent soixante-dix-sept patients ont été recrutés, dont la moitié étaient des hommes, l’âge médian était de 27 ans (2–98). Les lésions ont été classées en six catégories : urticaire (n = 26, 9 %), vésicules (n = 41, 15 %), lésions acrales (n = 142, 51 %), morbilliformes (n = 25, 9 %), pétéchiales (n = 7, 3 %), livedo reticularis (n = 4, 1 %) et autres (n = 41, 15 %). Certains patients présentaient des signes cutanés correspondant à plusieurs catégories. Les lésions acrales étaient particulièrement fréquentes (n = 142). Les lésions ressemblant à des engelures étaient les plus fréquentes des lésions acrales (n = 106/142, 75 %). Des lésions vésiculaires acrales (de type dyshidrose) étaient signalées dans 20 cas (14 %). Une acrodynie était présente dans 18 cas (6 %), parfois isolée. Parmi les 277 patients, 34 avaient subi une PCR nasopharyngée SARS-Cov-2, dont 25 étaient positives (74 %). Sept de ces 25 (28 %) avaient des lésions acrales. Parmi les patients sans test PCR positif, 115 patients présentaient des symptômes extracutanés évocateurs et/ou avaient signalé un contact étroit avec un patient atteint de COVID-19. L’examen histologique de 3 lésions de type engelures révélait une dermatite lichénoïde avec un infiltrat mononucléé périvasculaire et eccrine et des microthrombi vasculaires dans 2 cas.

Discussion

Notre étude apporte une description de la riche symptomatologie cutanée liée au SARS-Cov-2. Bien que le nombre de patients testés ne nous permette pas de tirer des conclusions définitives concernant un lien direct entre le SARS-Cov-2 et ces lésions cutanées, l’épidémie inattendue de lésions cutanées acrales dans ce contexte épidémique suggère un lien dont la physiopathologie mérite de futures investigations.

[Association of borderline tuberculoid leprosy and tuberculosis: A case report and review of the literature]

INTRODUCTION

In metropolitan France, nearly 20 new cases of leprosy are diagnosed each year. The incidence of tuberculosis in France is 8/100,000 inhabitants and there are very few accounts of association of these two mycobacteria. Herein we report a case of co-infection with borderline tuberculoid (BT) leprosy and disseminated tuberculosis diagnosed in metropolitan France.

PATIENTS AND METHODS

A male subject presented with diffuse painless infiltrated erythematous plaques. The biopsy revealed perisudoral and perineural lymphohistiocytic epithelioid cell granuloma as well as acid-alcohol-fast bacilli on Ziehl staining. PCR was positive for Mycobacterium leprae, confirming the diagnosis of leprosy in the BT form. The staging examination revealed predominantly lymphocytic left pleural effusion, right-central necrotic adenopathy without histological granuloma, negative screening for BK, a positive QuantiFERON-TB™ test, and a positive intradermal tuberculin reaction. The clinical and radiological results militated in favour of disseminated tuberculosis. Combined therapy (rifampicin, isoniazid, ethambutol and pyrazinamide) together with clofazimine resulted in regression of both cutaneous and extra-cutaneous lesions. This rare co-infection combines leprosy, often present for several years, and tuberculosis (usually pulmonary) of subsequent onset. The pathophysiological hypothesis is that of cross-immunity (with anti-TB immunity protecting against subsequent leprosy and vice versa), supported by the inverse correlation of the two levels of prevalence and by the protection afforded by tuberculosis vaccination. In most cases, treatment for TB and leprosy improves both diseases. Patients presenting leprosy should be screened for latent tuberculosis in order to avoid reactivation, particularly in cases where corticosteroid treatment is being given.

[Cutaneous plasmacytosis with Darier's sign in a woman of European origin]

INTRODUCTION

Cutaneous plasmacytosis is a rare skin condition first described in 1976 and it is seen mainly in patients of Asian descent. Patients usually present with multiple reddish-brown macules and nodules chiefly on the trunk and face, with clusters of well-differentiated plasma cells in the dermis. The aetiopathogenesis and nosological features of this entity remain obscure. We report herein a case of cutaneous plasmacytosis in a European middle-aged woman with presence of Darier's sign.

PATIENTS AND METHODS

A 56-year-old woman of European descent presented with asymptomatic hyperpigmented patches affecting the dorsal aspect of her trunk for at least two years. Darier's sign was present in some episodes. Cutaneous biopsy showed a moderately dense interstitial and perivascular infiltrate containing numerous well-differentiated mature plasma cells affecting the entire dermal surface. Kappa and lambda immunochemistry demonstrated polyclonal plasma cell infiltrates with absence of light-chain restriction. Immunohistochemical examination was negative for HHV-8 and Treponema pallidum spirochetes. Laboratory findings revealed hypergammaglobulinaemia with no monoclonal bands being detected on immunofixation. A diagnosis of cutaneous plasmacytosis was made. In the absence of systemic involvement initial management consisted of clinical surveillance.

DISCUSSION

The characteristic clinico-pathological features of CP allowed diagnosis of this skin condition in our patient, although it is very rarely reported in patients of European descent. The main differential diagnoses were ruled out, namely plasmacytic infiltrates related to infections and marginal B-cell lymphoma.