Proposal for a 6-step-approach for differential diagnosis of neonatal erythroderma

The broad differential diagnosis of neonatal erythroderma often poses a diagnostic challenge. Mortality of neonatal erythroderma is high due to complications of the erythroderma itself and the occasionally severe and life-threatening underlying disease. Early correct recognition of the underlying cause leads to better treatment and prognosis. Currently, neonatal erythroderma is approached by a case by case basis. The purpose of this scoping review was to develop a diagnostic approach in neonatal erythroderma. After a systematic literature search in Embase (January 1990 - May 2020, 74 cases of neonatal erythroderma were identified, and 50+ diagnoses could be extracted. Main causes were the ichthyoses (40%) and primary immunodeficiencies (35%). Congenital erythroderma was present in 64% (47/74) of the cases, predominantly with congenital ichthyosis (11/11; 100%), Netherton syndrome (12/14, 86%), and Omenn syndrome (11/23, 48%). Time until diagnosis ranged from 102 days to 116 days for cases of non-congenital erythroderma and congenital erythroderma respectively. Among the 74 identified cases a total of 17 patients (23%) died within a mean of 158 days and were related to Omenn syndrome (35%), graft versus host disease (67%), and Netherton syndrome (18%). Disease history and physical examination are summarized in this paper. Age of onset and a collodion membrane can help to narrow the differential diagnoses. Investigations of blood, histology, hair analysis, genetic analysis and clinical imaging are summarized and discussed. A standard blood investigation is proposed and the need for skin biopsies with Lympho-Epithelial Kazal-Type related Inhibitor-staining is highlighted. Overall, this review shows that diagnostic procedures narrow the differential diagnosis in neonatal erythroderma. A 6-step flowchart for the diagnostic approach for neonatal erythroderma during the first month of life is proposed. The approach was made with the support of expert leaders from international multidisciplinary collaborations in the European Reference Network Skin-subthematic group Ichthyosis.

[Tuberous sclerosis complex: analysis of areas of involvement, treatment progress and translation to routine clinical practice in a cohort of paediatric patients]

INTRODUCTION

Tuberous sclerosis complex (TSC) displays great phenotypic variability. Increasingly early diagnosis, including prenatal identification, entails the need for the paediatrician and neuropaediatrician to establish early suspicion and identification of factors that may influence prognosis and treatment.

AIM

To determine the clinical criteria for early diagnosis, initial complementary tests, actions and treatments to prevent different comorbidities, so as to improve the prognosis of these patients.

PATIENTS AND METHODS

Descriptive, retrospective study of = 18-year-olds with a definitive diagnosis of TSC in a tertiary hospital from 1998 to 2019. We collected variables referring to epidemiological data, multisystem involvement, complementary tests and genetics.

RESULTS

Ninety-four patients were analysed. The main diagnostic reasons were epilepsy and rhabdomyomas. The frequency of occurrence of clinical criteria was determined, and neuropathological findings were the main findings, followed by cutaneous stigmata, rhabdomyomas and renal lesions. Statistical relationships were found between clinical, radiological and genetic aspects, the influence of preventive activities on the occurrence of epilepsy and the relevance of everolimus use were tested.

CONCLUSIONS

Rhabdomyomas and skin stigmata in patients and parents are major diagnostic signs in infants. Tubers and subependymal nodules are statistically associated with the development of epilepsy. Early epileptic spasms, refractory to treatment in the first months, increase the risk of cognitive deficits and autism spectrum disorder. Epileptic abnormalities need to be closely monitored in the first year of life. Everolimus is an alternative treatment for several comorbidities, but its early use (< 3 years) requires further study.

Childhood rosacea and related disorders

Rosacea is a chronic inflammatory condition that affects the skin and the eyes. The pathogenesis of rosacea is complex and includes the interaction between genetic and environmental factors, dysregulation of the innate immune system, neurovascular modifications and the interaction with skin commensals. Clinical manifestations in children include the telangiectatic form, papulopustular rosacea, ocular rosacea, periorificial dermatitis, granulomatous rosacea and idiopathic facial aseptic granuloma. Management is aimed at identifying and avoiding triggers. Topical therapy is used for mild cases with topical antibiotics and anti-inflammatory agents. Oral agents are indicated, in combination with topical therapy, for moderate to severe cases. Prolonged therapy may be required.

Skin manifestations of COVID-19 in children: Part 3

The current COVID‐19 pandemic is caused by the SARS‐CoV‐2 coronavirus. The initial recognized symptoms were respiratory, sometimes culminating in severe respiratory distress requiring ventilation, and causing death in a percentage of those infected. As time has passed, other symptoms have been recognized. The initial reports of cutaneous manifestations were from Italian dermatologists, probably because Italy was the first European country to be heavily affected by the pandemic. The overall clinical presentation, course and outcome of SARS‐CoV‐2 infection in children differ from those in adults as do the cutaneous manifestations of childhood. In this review, we summarize the current knowledge on the cutaneous manifestations of COVID‐19 in children after thorough and critical review of articles published in the literature and from the personal experience of a large panel of paediatric dermatologists in Europe. In Part 1, we discuss one of the first and most widespread cutaneous manifestations of COVID‐19, chilblain‐like lesions, and in Part 2 we expanded to other manifestations, including erythema multiforme, urticaria and Kawasaki disease‐like inflammatory multisystemic syndrome. In this part of the review, we discuss the histological findings of COVID‐19 manifestations, and the testing and management of infected children for both COVID‐19 and any other pre‐existing conditions.

Click here for the corresponding questions to this CME article.

Skin manifestations of COVID-19 in children: Part 1

The current COVID‐19 pandemic is caused by the SARS‐CoV‐2 coronavirus. The initial recognized symptoms were respiratory, sometimes culminating in severe respiratory distress requiring ventilation, and causing death in a percentage of those infected. As time has passed, other symptoms have been recognized. The initial reports of cutaneous manifestations were from Italian dermatologists, probably because Italy was the first European country to be heavily affected by the pandemic. The overall clinical presentation, course and outcome of SARS‐CoV‐2 infection in children differ from those in adults as do the cutaneous manifestations of childhood. In this review, we summarize the current knowledge on the cutaneous manifestations of COVID‐19 in children after thorough and critical review of articles published in the literature and from the personal experience of a large panel of paediatric dermatologists in Europe. In Part 1, we discuss one of the first and most widespread cutaneous manifestation of COVID‐19, chilblain‐like lesions. In Part 2, we review other manifestations, including erythema multiforme, urticaria and Kawasaki disease‐like inflammatory multisystemic syndrome, while in Part 3, we discuss the histological findings of COVID‐19 manifestations, and the testing and management of infected children, for both COVID‐19 and any other pre‐existing conditions.

Click here for the corresponding questions to this CME article.

SARS-CoV-2 endothelial infection causes COVID-19 chilblains: histopathological, immunohistochemical and ultrastructural study of seven paediatric cases

Background

Chilblains (‘COVID toes’) are being seen with increasing frequency in children and young adults during the COVID‐19 pandemic. Detailed histopathological descriptions of COVID‐19 chilblains have not been reported, and causality of SARS‐CoV‐2 has not yet been established.

Objectives

To describe the histopathological features of COVID‐19 chilblains and to explore the presence of SARS‐CoV‐2 in the tissue.

Methods

We examined skin biopsies from seven paediatric patients presenting with chilblains during the COVID‐19 pandemic. Immunohistochemistry for SARS‐CoV‐2 was performed in all cases and electron microscopy in one.

Results

Histopathology showed variable degrees of lymphocytic vasculitis ranging from endothelial swelling and endotheliitis to fibrinoid necrosis and thrombosis. Purpura, superficial and deep perivascular lymphocytic inflammation with perieccrine accentuation, oedema, and mild vacuolar interface damage were also seen. SARS‐CoV‐2 immunohistochemistry was positive in endothelial cells and epithelial cells of eccrine glands. Coronavirus particles were found in the cytoplasm of endothelial cells on electron microscopy.

Conclusions

Although the clinical and histopathological features were similar to other forms of chilblains, the presence of viral particles in the endothelium and the histological evidence of vascular damage support a causal relation of the lesions with SARS‐CoV‐2. Endothelial damage induced by the virus could be the key mechanism in the pathogenesis of COVID‐19 chilblains and perhaps also in a group of patients severely affected by COVID‐19 presenting with features of microangiopathic damage.

What is already known about this topic?

Despite the high number of cases of chilblains seen during the COVID‐19 pandemic, a definite causative role for SARS‐CoV‐2 has not yet been proven.

Different pathogenetic hypotheses have been proposed, including coagulation anomalies, interferon release and external factors.

What does this study add?

The demonstration of SARS‐CoV‐2 in endothelial cells of skin biopsies by immunohistochemistry and electron microscopy confirms that these lesions are part of the spectrum of COVID‐19.

Virus‐induced vascular damage and secondary ischaemia could explain the pathophysiology of COVID‐19 chilblains.

Our findings support the hypothesis that widespread endothelial infection by SARS‐CoV‐2 could have a pathogenetic role in the severe forms of COVID‐19.

Linked Comment:  Wetter. Br J Dermatol 2020; 183:611.

Spitz Nevus and Other Spitzoid Tumors in Children. Part 2: Cytogenetic and Molecular Features. Prognosis and Treatment

Melanocytic neoplasms with spitzoid morphology (Spitz nevi, atypical Spitz tumors, and spitzoid melanomas) may be benign or malignant. Because the malignant potential of atypical Spitz tumors is uncertain, the proper therapeutic approach has been much debated over the years. Promising new techniques for molecular analysis have enabled better predictions of the biological behavior of these tumors. We review their cytogenetic features and prognosis and also provide an update of the most recent recommendations for management.

Management of congenital ichthyoses: European guidelines of care, part two

These guidelines for the management of congenital ichthyoses have been developed by a multidisciplinary group of European experts following a systematic review of the current literature, an expert conference held in Toulouse in 2016, and a consensus on the discussions. These guidelines summarize evidence and expert-based recommendations and intend to help clinicians with the management of these rare and often complex diseases. These guidelines comprise two sections. This is part two, covering the management of complications and the particularities of some forms of congenital ichthyosis.

A Retrospective Study of Systemic Treatment of Severe Atopic Dermatitis With Azathioprine: Effectiveness and Tolerance in 11 Pediatric Patients

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease that typically affects children. Severe forms may have a profound effect on patients' quality of life. Some forms are resistant to conventional treatment and require the use of systemic immunosuppressants such as azathioprine (AZA) to adequately manage the disease.

OBJECTIVE

To evaluate the effectiveness and tolerance of AZA in children with severe AD.

PATIENTS AND METHODS

We performed a retrospective study of children with severe AD treated with AZA between January 2007 and May 2017.

RESULTS

We reviewed the cases of 11 patients (6 boys and 5 girls) with a mean age of 13 years (range, 8-18 years). The mean (SD) age at start of treatment was 10.9 (2.2) years (95% CI 8.6-13.1). The mean initial dosage of AZA was 1.8 (0.2) mg/kg/d. We evaluated treatment response after 4 weeks, 12 to 16 weeks, and 6 months. Mean treatment duration was 10.8 (5.7) months. Treatment had to be suspended in 2 patients because of adverse effects. Seven of the 9 remaining patients presented complete or almost complete clearance of the AD after 6 months of treatment.

CONCLUSION

In our experience, AZA is well tolerated and may be considered as a treatment option in children with severe AD resistant to conventional treatment.

An Update on Neurofibromatosis Type 1: Not Just Café-au-Lait Spots, Freckling, and Neurofibromas. An Update. Part I. Dermatological Clinical Criteria Diagnostic of the Disease

Neurofibromatosis type 1 (NF1) is the most common neurocutaneous syndrome and probably the one best known to dermatologists, who are generally the first physicians to suspect its diagnosis. Although the genetic locus of NF1 was identified on chromosome 17 in 1987, diagnosis of the disease is still mainly based on clinical observations and the diagnostic criteria of the National Institute of Health, dating from 1988. Cutaneous manifestations are particularly important because café-au-lait spots, freckling on flexural areas, and cutaneous neurofibromas comprise 3 of the 7 clinical diagnostic criteria. However, café-au-lait spots and freckling can also be present in other diseases. These manifestations are therefore not pathognomonic and are insufficient for definitive diagnosis in the early years of life. NF1 is a multisystemic disease associated with a predisposition to cancer. A multidisciplinary follow-up is necessary and dermatologists play an important role.

An Update on Neurofibromatosis Type 1: Not Just Café-au-Lait Spots and Freckling. Part II. Other Skin Manifestations Characteristic of NF1. NF1 and Cancer

Neurofibromatosis type 1 (NF1) is the most common neurocutaneous syndrome and probably the one best known to dermatologists. Although the genetic locus of NF1 was identified on chromosome 17 in 1987, diagnosis of the disease is still based primarily on clinical observations. The 7 diagnostic criteria of the National Institutes of Health, which were established in 1988, include 3 skin manifestations (café-au-lait spots, freckling on flexural areas, and cutaneous neurofibromas). The age at which these diagnostic lesions appear is variable: onset can be late in some patients while others never develop certain symptoms. Definitive diagnosis may therefore be delayed by years. Although the appearance of the characteristic café-au-lait spots and freckling in the early years of childhood are very suggestive of the disease, these signs are not pathognomonic and, in isolation, do not constitute sufficient evidence to establish a definitive diagnosis. Thus, other diagnoses should be considered in patients whose only symptoms are café-au-lait spots and freckling. By contrast, the presence of multiple cutaneous neurofibromas or at least 1 plexiform neurofibroma is a very specific indication of NF1. Identification of the different types of neurofibroma allows us to confirm the diagnosis and initiate appropriate management.

Early-onset acral basal cell carcinomas in Gorlin syndrome

Two patients are reported in whom early-onset, distal papules with a histopathological diagnosis of basal cell carcinoma were the first manifestation of Gorlin syndrome (GS). These lesions showed no progression and remained stable through follow-up. Two different PTCH1 gene mutations were detected in the two patients, and thus a phenotype-genotype correlation of this manifestation of GS was not possible.

Molecular evidence of type 2 mosaicism in Gorlin syndrome

We present a 12-year-old girl with a family history of Gorlin syndrome who had unilateral, segmentally arranged basaloid skin tumours present since birth, ipsilateral, palmoplantar pits of rather large size distributed along Blaschko lines, and an ipsilateral odontogenic keratocyst. The patient and her father were heterozygous for a germline mutation in the form of a single-base substitution in exon 18 of the PTCH1 gene. In the patient's lesional skin, a microdeletion in exon 3 of PTCH1 was detected, giving rise to a truncated protein. This additional mutation was ruled out in the contralateral skin and in blood lymphocytes, thus confirming its mosaic state. In this way we provide for the first time molecular proof of a type 2 segmental involvement of this autosomal dominant trait.

First symposium of ichthyosis experts

On June 22, 2012 the First Symposium of Ichthyosis Experts in Spain was held at the Hospital Niño de Jesús in Madrid. It was a one-day symposium for dermatologists, pediatricians, and physicians-in-training interested in this disease, as well as for other health care professionals involved in the care of patients with ichthyosis. The aim of the meeting was to try to structure the care of ichthyosis patients in Spain. As happens in other rare diseases, because of the low prevalence of ichthyosis and the absence of designated referral centers, the number of patients treated in each center is very low and few dermatologists have any real clinical experience with this condition or know how to order diagnostic genetic tests. This article summarizes the presentations given at the symposium and is intended as a reference for anyone interested in the subject.

Ectodermal dysplasias: a clinical and molecular review

The ectodermal dysplasias are a large group of hereditary disorders characterized by alterations of structures of ectodermal origin. Although some syndromes can have specific features, many of them share common clinical characteristics. Two main groups of ectodermal dysplasias can be distinguished. One group is characterized by aplasia or hypoplasia of ectodermal tissues, which fail to develop and differentiate because of a lack of reciprocal signaling between ectoderm and mesoderm, the other has palmoplantar keratoderma as its most striking feature, with additional manifestations when other highly specialized epithelia are also involved. In recent decades, the genes responsible for at least 30 different types of ectodermal dysplasia have been identified, throwing light on the pathogenic mechanisms involved and their correlation with clinical findings.

Clinical, molecular and biochemical characterization of nine Spanish families with Conradi-Hünermann-Happle syndrome: new insights into X-linked dominant chondrodysplasia punctata with a comprehensive review of the literature

BACKGROUND

Conradi-Hünermann-Happle syndrome (CDPX2, OMIM 302960) is an inherited X-linked dominant variant of chondrodysplasia punctata which primarily affects the skin, bones and eyes. CDPX2 results from mutations in EBP (emopamil binding protein), and presents with increased levels of sterol precursors 8(9)-cholesterol and 8-dehydrocholesterol.

OBJECTIVES

To expand the understanding of CDPX2, clinically, biochemically and genetically.

METHODS

We present one of the largest series reported to date, including 13 female patients belonging to nine Spanish families. Patients were studied biochemically using gas chromatography-mass spectrometry, genetically using polymerase chain reaction and in their methylation status using the HUMARA assay.

RESULTS

In our cases, there was a clear relationship between abnormal sterol profile and the EBP gene mutation. We describe three novel mutations in the EBP gene. EBP mutations were inherited in three out of nine families and were sporadic in the remaining cases.

CONCLUSIONS

No clear genotype-phenotype correlation was found. Patients' biochemical profiles did not reveal a relationship between sterol profiles and severity of disease. A skewed X-chromosome inactivation may explain the clinical phenotype in CDPX2 in some familial cases.

Two novel recessive mutations in KRT14 identified in a cohort of 21 Spanish families with epidermolysis bullosa simplex

BACKGROUND

Basal epidermolysis bullosa simplex (EBS) is a group of blistering genodermatoses mostly caused by mutations in the keratin genes, KRT5 and KRT14. Recessive mutations represent about 5% of all EBS mutations, being common and specific in populations with high consanguinity, where affected patients show severe phenotypes.

OBJECTIVES

To accomplish the first mutational analysis in patients of Spanish origin with EBS and to delineate a comprehensive genotype-phenotype correlation.

METHODS

Twenty-one EBS families were analysed. Immunofluorescence mapping at the dermoepidermal junction level was performed on skin biopsies from patients. Mutation screening of the entire coding sequences of KRT5 and KRT14 in genomic DNA was assessed by polymerase chain reaction and direct sequencing.

RESULTS

KRT5 or KRT14 causative mutations were identified in 18 of the 21 EBS families. A total of 14 different mutations were disclosed, of which 12 were dominant missense mutations and two truncating recessive mutations. Five of the 14 mutations were novel including three dominant in KRT5 (p.V186E, p.T321P and p.A428T) and two recessive in KRT14 (p.K116X and p.K250RfsX8). The two patients with EBS carrying homozygous recessive mutations were affected by severe phenotypes and belonged to consanguineous families. All five families with the EBS Dowling-Meara subtype carried recurrent mutations affecting the highly conserved ends of the α-helical rod domain of K5 and K14. The seven mutations associated with the localized EBS subtype were widely distributed along the KRT5 and KRT14 genes. Two families with mottled pigmentation carried the P25L mutation in KRT5, commonly associated with this subtype.

CONCLUSIONS

This study further confirms the genotype-phenotype correlation established for EBS in other ethnic groups, and is the first in a Mediterranean country (excluding Israel). This study adds two novel recessive mutations to the worldwide record to date, which includes a total of 14 mutations. As in previous reports, the recessive mutations resulted in a lack of keratin K14, giving rise to a generalized and severe presentation.