Precision diagnostics in paediatric dermatology: Advancing management of tinea capitis through dermatophyte PCR.

BACKGROUND: Tinea capitis (TC) is the most frequent dermatophyte infection in children requiring systemic and topical treatment for several weeks. Traditionally, diagnosis and treatment monitoring were based on microscopic examination and fungal culture of scales and plucked hairs, which both have significant limitations. OBJECTIVES: To investigate the role of dermatophyte polymerase chain reaction (PCR) in the treatment of TC. METHODS: Scales and plucked hairs of children with TC were investigated by dermatophyte PCR, microscopic examination and fungal culture at baseline and during antifungal treatment. RESULTS: Seventeen children with TC were included. At baseline, sensitivity of PCR was 100% as compared to 60% and 87% for direct microscopy and fungal culture, respectively. Species identification by PCR and fungal culture was consistent in all cases. During follow-up, analysis of 38 samples under treatment showed a sensitivity of PCR, direct microscopy and fungal culture of 68%, 26% and 89% while specificity was 84%, 100% and 100%, respectively. PCR during therapy proved to be false-negative in six and false-positive in three instances. The latter turned negative after 4 weeks without further systemic treatment. CONCLUSIONS: Dermatophyte PCR is an excellent tool for baseline diagnostics of TC providing rapid and accurate results. Our findings suggest that due to the fast and reliable results, it may replace direct microscopy and fungal culture to confirm or exclude TC in children. In the treatment course, diagnostic accuracy and performance of PCR seem reduced as compared to fungal culture, limiting its value for treatment monitoring. Mycological cure ascertained by fungal culture should currently remain the therapeutic goal.

Cerebriform sebaceous nevus: a subtype of organoid nevus due to specific postzygotic FGFR2 mutations.

BACKGROUND: Postzygotic mutations in FGFR2 have been identified in mosaic forms of acne, keratinocytic epidermal nevi, nevoid acanthosis nigricans / rounded and velvety epidermal nevus and in two fetuses with papillomatous pedunculated sebaceous nevus (PPSN). OBJECTIVES: To determine the clinical and genetic characteristics of children with cerebriform, papillomatous and pedunculated variants of sebaceous nevi. METHODS: Infants diagnosed with sebaceous nevi characterized by a cerebriform, papillomatous and/or pedunculated morphology over a 10-year period (2010-2019) at three paediatric dermatology centres in Switzerland and France were included in this case series. Clinical and histological characteristics were assessed. Next-generation sequencing was used to assess for FGFR2 mutations. RESULTS: All nevi were located on the head, with a rounded or linear shape and a typical cerebriform, sometimes papillomatous and pedunculated, surface. No associated extracutaneous anomalies were found. Nevi harboured postzygotic mutations in the transmembrane domain of FGFR2 in 6/8 children (75%), either the known specific p.(Cys382Arg) mutation in 5 cases, or a novel mutation, p.(Val395Asp), in one. CONCLUSIONS: We found an exquisite genotype-phenotype correlation in these rare nevi, with specific postzygotic mutations in the transmembrane domain of FGFR2. As not all lesions were truly papillomatous and pedunculated, the term cerebriform sebaceous nevus (CSN) appears more suitable than PPSN to describe this entity. The cerebriform pattern of CSN is reminiscent of cutis gyrata, as seen in Beare-Stevenson syndrome, which is caused by closely related germline FGFR2 mutations. While clinically impressive, CSN seem to carry a good prognosis and a low risk for extracutaneous associations.

Diagnosis and management of morphoea in children: an overview.

Paediatric morphoea (localized scleroderma) is an inflammatory sclerosing disorder of the skin and subcutis associated with tissue atrophy. It is thought that the disease develops on the background of genetic predisposition (e.g. mosaicism for the common linear variant) initiated by various trigger factors, and that detected autoantibodies and inflammatory cytokines represent secondary epiphenomena. In contrast to the common belief that morphoea is a benign self-limiting disorder, long-term data indicate that its chronicity, relapsing nature and extracutaneous complications lead to significant morbidity, particularly when the disease starts in early childhood. Early recognition may be challenging, and the most important clinical clues are band-like distribution, atrophy of underlying tissue, skin sclerosis, and localized loss of body/scalp hair, eyelashes or eyebrows. Extracutaneous manifestations occur in up to 20% of patients, with arthritis/arthralgia and neurological symptoms being most frequently observed, followed by ophthalmological complications such as uveitis. Corticosteroids and methotrexate are highly effective as first-line therapy in morphoea, leading to partial reversal of skin manifestations. However, the development of atrophy is not sufficiently prevented by standard therapy. There is a relapse rate of 25%-48% within the first years after stopping treatment, thus long-term follow-up is warranted. Mycophenolate mofetil seems to be a beneficial second-line therapy, and a new drug, abatacept, also seems to be a promising and well-tolerated second-line treatment option. Additionally, autologous fat injections are beneficial and may be used as an adjunct to ongoing therapy.

Prospective evaluation of treatment response and disease reversibility of paediatric localized scleroderma (morphoea) to steroids and methotrexate using multi-modal imaging.

BACKGROUND: Paediatric localized scleroderma is a severe inflammatory disorder associated with tissue atrophy, often leading to disability. Assessing disease activity and response to treatment has always been challenging and remains an important difficulty in clinical practice. OBJECTIVES: To investigate prospectively the efficacy of systemic treatment with corticosteroids and methotrexate in children with localized scleroderma and the validity of infrared thermography, laser Doppler flowmetry and high-frequency ultrasound in assessing disease activity. METHODS: Children with localized scleroderma were prospectively treated with corticosteroids (initially pulsed IV methylprednisolone 30 mg/kg/day, maximum 500 mg/day and/or oral prednisolone 0.5-1 mg/kg/day) and methotrexate (15 mg/m2 weekly). Treatment response was evaluated using a clinical activity score. Skin temperature, blood flow, dermal thickness and dermal echogenicity of clinically active skin lesions were determined in relation to the unaffected contralateral site at baseline and after 3, 6, 12 and 18 months. Patient charts were later reviewed for long-term follow-up. RESULTS: Twenty-two patients were included [age 6.0 (0.2-14.4] years; female-to-male ratio 3.4 : 1) All responded well to therapy. Disease reversibility was demonstrated in the majority of children with partial resolution of skin sclerosis and regrowth of hair. Laser Doppler flowmetry and high-frequency ultrasound findings correlated with disease activity at baseline. Thermography had no added value in this cohort. The recurrence rate was 36% in the follow-up period. CONCLUSIONS: Corticosteroids and methotrexate are highly effective as first-line therapy in paediatric localized scleroderma, leading to partial reversal of skin manifestations. However, the recurrence rate is substantial and affected children require long-term follow-up. Laser Doppler flowmetry and high-frequency ultrasound correlate with disease activity in the acute phase and may assist decision-making in these patients.

Safe and effective use of alitretinoin in children with recalcitrant hand eczema and other dermatoses - a retrospective analysis.

BACKGROUND: Alitretinoin is a systemic retinoid licensed for use in adult patients suffering from chronic hand eczema recalcitrant to potent topical steroids. Experience with its use in childhood is lacking. OBJECTIVES: To report on the efficacy and safety of alitretinoin treatment in a cohort of children and adolescents with chronic hand eczema (CHE) and other inflammatory skin diseases. METHODS: We performed a retrospective chart review of all consecutive patients under the age of 18 years treated with alitretinoin at our paediatric skin centre. Physician's Global Assessment (PGA) was used as the primary outcome measure. RESULTS: Thirteen children (9 girls and 4 boys) were enrolled in this study. The median age at start of treatment with alitretinoin was 11.5 years (range 5.8-15.8 years). Nine children were diagnosed with CHE, two with severe atopic dermatitis (AD), and two with inherited ichthyosis [netherton syndrome (NS), autosomal recessive congenital ichthyosis (ARCI)]. Moderate to excellent response (PGA decrease of ≥1 point) was observed in 7 (78%) of the nine patients with CHE, one of the two patients with extensive AD and in the one patient with ARCI. In the remaining four subjects, no convincing effect was documented. Tolerability was overall very good. The most common adverse event was headache in 10 patients (77%) during the initiation of treatment, leading to interruption of therapy in one subject. CONCLUSIONS: Alitretinoin seems to be highly effective and safe for the treatment of paediatric CHE and should thus be considered in children with refractory disease under topical therapy. Larger studies are required to corroborate these findings.

Sustained long-term efficacy and safety of adalimumab in paediatric patients with severe chronic plaque psoriasis from a randomized, double-blind, phase III study.

BACKGROUND: Adalimumab (ADA) (Humira® , AbbVie Inc., U.S.A.) is approved by the European Medicines Agency for children aged ≥ 4 years with severe plaque psoriasis. OBJECTIVES: To evaluate the long-term efficacy and safety of ADA in children with severe plaque psoriasis. METHODS: Results are presented from the 52-week long-term extension (LTE) of the randomized, double-blind, double-dummy, phase III trial, in children with severe plaque psoriasis (results from prior periods have been published). Patients aged ≥ 4 and < 18 years were randomized 1 : 1 : 1 to ADA 0·8 mg kg-1 (40 mg maximum) or 0·4 mg kg-1 (20 mg maximum) every other week or to methotrexate (MTX) 0·1-0·4 mg kg-1 (25 mg maximum) weekly. The 16-week initial treatment (IT) period was followed by a 36-week withdrawal period and a 16-week retreatment period. Patients could enter the LTE at prespecified time points to receive ADA 0·8 mg kg-1 (blinded or open label) or ADA 0·4 mg kg-1 (blinded), or to remain off treatment. Efficacy is reported for patient groups according to doses received in the IT and LTE periods. RESULTS: Of the 114 patients randomized in the IT period, 108 entered the LTE (n = 36 in each group); 93 received ADA 0·8 mg kg-1 . Efficacy (≥ 75% improvement from baseline in Psoriasis Area and Severity Index) was maintained or improved from entry to the end of the LTE: MTX(IT)/ADA 0·8(LTE) 31-86% of patients; ADA 0·4(IT)/0·4 or 0·8(LTE) 28-47%; ADA 0·8(IT)/0·8(LTE) 50-72%. No serious infections occurred in the LTE. CONCLUSIONS: After 52 weeks of long-term ADA treatment in children aged 4-18 years with severe plaque psoriasis, disease severity was reduced and maintained or further improved, as demonstrated by efficacy outcomes. No new safety risks were identified. What's already known about this topic? The results from the first three periods of this phase III trial in children aged 4-18 years with severe plaque psoriasis suggest that adalimumab is a safe and efficacious treatment option in this population. What does this study add? This is the first study to evaluate long-term treatment of adalimumab in children with severe psoriasis, and the first to evaluate switching from methotrexate to adalimumab in this population.

Differential expression of secreted factors SOSTDC1 and ADAMTS8 cause profibrotic changes in linear morphoea fibroblasts.

BACKGROUND: Linear morphoea (LM) is a rare connective tissue disorder characterized by a line of thickened skin and subcutaneous tissue and can also affect the underlying muscle and bone. Little is known about the disease aetiology, with treatment currently limited to immune suppression, and disease recurrence post-treatment is common. OBJECTIVES: In order to uncover new therapeutic avenues, the cell-intrinsic changes in LM fibroblasts compared with site-matched controls were characterized. METHODS: We grew fibroblasts from site-matched affected and unaffected regions from five patients with LM, we subjected them to gene expression analysis and investigation of SMAD signalling. RESULTS: Fibroblasts from LM lesions showed increased migration, proliferation, altered collagen processing, and abnormally high basal levels of phosphorylated SMAD2, thereby rendering them less responsive to transforming growth factor (TGF)-ß1 and reducing the degree of myofibroblast differentiation, which is a key component of the wound-healing and scarring process in normal skin. Conditioned media from normal fibroblasts could reverse LM-affected fibroblast migration and proliferation, suggesting that the LM phenotype is driven by an altered secretome. Gene array analysis and RNA-Seq indicated upregulation of ADAMTS8 and downregulation of FRAS1 and SOSTDC1. SOSTDC1 knock-down recapitulated the reduced TGF-ß1 responsiveness and LM fibroblast migration, while overexpression of ADAMTS8 induced myofibroblast markers. CONCLUSIONS: We demonstrate that cell-intrinsic changes in the LM fibroblast secretome lead to changes observed in the disease, and that secretome modulation could be a viable therapeutic approach in the treatment of LM.

[Acute skin infections and their imitators in children : A photo quiz]. / Akute Hautinfektionen und deren Imitatoren im Kindesalter : Ein Bilderquiz.

BACKGROUND: Skin infections account for 40% of emergency visits in pediatric dermatology. It is important to promptly recognize skin infections with potential complications and initiate treatment. However some characteristic skin findings may imitate skin infections and are often misdiagnosed. OBJECTIVES: To illustrate frequent pediatric skin infections and pitfalls in view of imitators and differential diagnoses. MATERIALS AND METHODS: A photo quiz is presented with the discussion of a selection of acute pediatric skin infections in comparison to their infectious or noninfectious differential diagnoses. RESULTS: The following infectious skin conditions and imitators are described and clinical clues for differentiation highlighted: eczema herpeticum and bacterial superinfection of atopic dermatitis; exanthematous hand, foot and mouth disease and varicella infection; erythema chronicum multilocularis and anular urticaria; Gianotti-Crosti syndrome and Gianotti-Crosti-like reaction; bacterial folliculitis of the scalp and kerion celsi and eosinophilic pustular folliculitis of the scalp; cutaneous Leishmaniasis and idiopathic facial aseptic granuloma; allergic and bacterial lymphangitis; bullous impetigo contagiosa and nonaccidental scalding. CONCLUSIONS: Careful anamnesis and skin examination with attention to the here illustrated differential diagnoses are essential to avoid pitfalls in the evaluation of acute pediatric skin infections.

[Congenital nevi in childhood]. / Kongenitale Nävi im Kindesalter.

Nevi represent congenital hamartomatous malformations of various components of the skin. The most common forms are congenital melanocytic nevi (CMN) and nevi of epithelial origin (epidermal and organoid nevi). Large CMN in particular can lead to severe complications and the management of those affected represents a challenge from birth. In contrast to previous assumptions, the risk of malignancy from CMN is considered to be relatively low however, this may be relevantly increased in certain situations. Possible extracutaneous symptoms in cases of central nervous system (CNS) involvement should not be underestimated and early imaging investigations are part of the routine diagnostic procedure. Surgical measures are still very important in the treatment of CMN but the indications must be weighed up for each individual case. Patients often experience marked stigmatization due to disfigurement by their birthmark and this needs to be taken into consideration for their treatment. The most common epithelial nevi are sebaceous nevi. In 2-13 % of cases additional tumors occur within this nevus and early surgical excision is indicated in most cases, not least for aesthetic reasons. If generalized spreading of epidermal nevi occurs, additional investigations are necessary to exclude associated ophthalmological, cardiac or neurological malformations.

[Localized scleroderma (morphea) in childhood]. / Lokalisierte Sklerodermie (Morphea) im Kindesalter.

Localized scleroderma or morphea is a sclerosing connective tissue disease of the skin, which may affect underlying tissues such as subcutis, muscle and bone. Many patients show extracutaneous symptoms and antinuclear antibodies, however, secondary transformation into systemic sclerosis does not occur. Localized scleroderma usually begins in childhood with a wide variation in its clinical spectrum. The linear variant is the most common subtype in children, associated with a progressive course and increased risk of complications. The disease may progress over years and result in severe functional and cosmetic disability. The etiology of localized scleroderma remains unknown. A genetic background is suspected, while triggers such as trauma, vaccinations and infections may lead to secondary immunologic phenomena. Localized scleroderma often remains unrecognized for a long time, resulting in substantial delay in treatment. The combination of systemic corticosteroids and methotrexate has been established as first-line therapy for progressive (usually linear) disease, whereas phototherapy (UVA-1 or UVB-narrow band) is suitable for adolescents with superficial circumscribed subtypes.

Vascular anomalies in children.

Vascular anomalies are divided in two major categories: tumours (such as infantile hemangiomas) and malformations. Hemangiomas are common benign neoplasms that undergo a proliferative phase followed by stabilization and eventual spontaneous involution, whereas vascular malformations are rare structural anomalies representing morphogenetic errors of developing blood vessels and lymphatics. It is important to properly diagnose vascular anomalies early in childhood because of their distinct differences in morbidity, prognosis and need for a multidisciplinary management. We discuss a number of characteristic clinical features as clues for early diagnosis and identification of associated syndromes.

Phacomatosis pigmentovascularis and extensive venous malformation of brain vessels: an unknown association or a new vascular neurocutaneous syndrome?

We report on a 16-year-old intelligent and sportive boy with the cutaneous findings of phacomatosis pigmentovascularis unclassifiable type.The skin anomaly was lateralised to his left body side since birth, fading over the years. Because of headache and dizziness, brain magnetic resonance imaging was performed, which revealed an impressive enlargement of subependymal, deep and superficial medullary veins on the right side combined with a mild atrophy of the ipsilateral parietal region. We propose to investigate patients with phacomatosis pigmentovascularis for associated venous brain malformations with adequate imaging techniques.

Misdiagnosis and delay in referral of children with localized scleroderma.

BACKGROUND: Localized scleroderma (LS) usually begins in childhood with a broad clinical spectrum and the diagnosis is often delayed. OBJECTIVES: To investigate the diagnostic pathway in a large cohort of paediatric patients with LS, to identify the duration until correct diagnosis and to characterize clinical clues for early diagnosis. METHODS: A retrospective case note review of 50 children with LS. RESULTS: The median (range) age at disease onset was 5·2 (0·1-14·4) years and disease duration until diagnosis 11·1 (1·8-79) months. The patients were first seen by a general practitioner (or paediatrician) after 1·2 (0·2-48·7) months and in none of the cases was the condition recognized at presentation according to a parental questionnaire (no diagnosis in 44%, misdiagnosis of atopic eczema 20%, melanocytic naevus 8%, fungal infection 6%, bruise 4%, varicose vein 4%, bacterial infection 4% and others). The patients were referred to a local specialist (dermatologist in 72%) after a disease duration of 7·5 (1·0-70·9) months and in 64% the correct diagnosis was established. In 20% the diagnosis remained unknown, 8% were misdiagnosed as port-wine stains and others as atopic eczema and melanocytic naevus. The correct diagnosis was eventually identified by the referring dermatologists, the paediatric dermatologists at our hospital, external maxillofacial surgeons and a paediatrician in 29 (58%), 17 (34%), 3 (6%) and 1 (2%), respectively. Histology was performed in 15 (30%). The patients were commenced on appropriate treatment after a disease duration of 16·6 (1·8-113·4) months. The main clinical diagnostic clues were: Blaschko-linear distribution 76%, atrophic changes 68%, skin fibrosis 40% and loss of scalp hair or eyelashes 36%. CONCLUSIONS: Physicians involved in the care of these children need to be aware of the characteristic clinical appearance of LS for early recognition and prompt initiation of treatment.