Clinical and molecular data in cases of prenatal localized overgrowth disorder: major implication of genetic variants in PI3K-AKT-mTOR signaling pathway.

OBJECTIVES: To describe clinical and molecular findings in a French multicenter cohort of fetuses with prenatal diagnosis of congenital abnormality and suspicion of a localized overgrowth disorder (LOD) suggestive of genetic variants in the PI3K-AKT-mTOR signaling pathway. METHODS: We analyzed retrospectively data obtained between 1 January 2013 and 1 May 2020 from fetuses with brain and/or limb overgrowth referred for molecular diagnosis of PI3K-AKT-mTOR pathway genes by next-generation sequencing (NGS) using pathological tissue obtained by fetal autopsy. We also assessed the diagnostic yield of amniotic fluid. RESULTS: During the study period, 21 subjects with LOD suspected of being secondary to a genetic variant of the PI3K-AKT-mTOR pathway were referred for analysis. Of these, 17 fetuses had brain overgrowth, including six with isolated megalencephaly (MEG) and 11 with hemimegalencephaly (HMEG). Of the six with MEG, germline variants were identified in four cases, in either PIK3R2, AKT3 or MTOR, and a postzygotic PIK3R2 variant was found in the other two cases. Of the 11 with HMEG, a postzygotic PIK3CA variant was found in three fetuses with extracerebral features of PIK3CA-related overgrowth spectrum, and in seven fetuses with isolated HMEG. No pathogenic variant was identified in the 11th case with HMEG. Four fetuses with limb overgrowth also had one or more lymphatic malformations (LM) and harbored a postzygotic PIK3CA variant. NGS on cultured amniocytes performed in 10 cases, of which nine had been found positive on analysis of pathological fetal tissue, showed variants in four, in either PIK3CA, PIK3R2 or AKT3. CONCLUSIONS: Isolated MEG or HMEG may lead to identification of genetic variants in the PI3K-AKT-mTOR signaling pathway. Cases of limb overgrowth and LM or isolated HMEG are likely associated with PIK3CA variants. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Safety and efficacy of low-dose PI3K inhibitor taselisib in adult patients with CLOVES and Klippel-Trenaunay syndrome (KTS): the TOTEM trial, a phase 1/2 multicenter, open-label, single-arm study.

PURPOSE: PIK3CA pathogenic variants in the PIK3CA-related overgrowth spectrum (PROS) activate phosphoinositide 3-kinase signaling, providing a rationale for targeted therapy, but no drug has proven efficacy and safety in this population. Our aim was to establish the six-month tolerability and efficacy of low-dose taselisib, a selective class I PI3K inhibitor, in PROS patients. METHODS: Patients over 16 years with PROS and PIK3CA pathogenic variants were included in a phase IB/IIA multicenter, open-label single-arm trial (six patients at 1 mg/day of taselisib, then 24 at 2 mg/day). The primary outcome was the occurrence of dose limiting toxicity (DLT). Efficacy outcomes were the relative changes after treatment of (1) tissue volume at affected and unaffected sites, both clinically and on imaging; (2) cutaneous vascular outcomes when relevant; (3) biologic parameters; (4) quality of life; and (5) patient-reported outcomes. RESULTS: Among 19 enrolled patients, 2 experienced a DLT (enteritis and pachymeningitis) leading to early trial termination (17 treated, 10 completed the study). No serious adverse reaction occurred in the 1 mg cohort (n = 6). No significant reduction in affected tissue volume was observed (mean -4.2%; p = 0.81; SD 14.01). Thirteen (76.4%) participants reported clinical improvement (pain reduction, chronic bleeding resolution, functional improvement). CONCLUSION: Despite functional improvement, the safety profile of low-dose taselisib precludes its long-term use.

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.

Acute acral eruptions in children during the COVID-19 pandemic: Characteristics of 103 children and their family clusters.

BACKGROUND: A marked increase in frequency of acute acral eruptions (AAE) was observed in children during the COVID-19 pandemic in the spring period. OBJECTIVES: In this observational multicenter study, based on children with AAE, we aimed to assess the proportion of household members possibly infected by SARS-CoV-2. METHODS: We collected data from all children observed with AAE, prospectively from April 7, 2020 to June 22, 2020, and retrospectively since February 28, 2020. The primary outcome was the household infection rate, defined as the proportion of family clusters having at least one member with COVID-19 infection other than the child with AAE ("index child"). The definition of a case was based on characteristic clinical signs and a positive PCR or serology. RESULTS: The study included 103 children in 10 French departments and in Quebec. The median age was 13 years and the interquartile range [8-15], with a female-to-male ratio of 1/1.15. In children with AAE, all PCR tests were negative (n=18), and serology was positive in 2/14 (14.3%) cases. We found no significant anomalies in the lab results. A total of 66 of the 103 families (64.1%) of included children had at least one other infected member apart from the index child. The total number of household members was 292, of whom 119 (40.8%) were considered possibly infected by SARS-CoV-2. No index children or households exhibited severe COVID-19. DISCUSSION: Among the 103 households included, 64.1% had at least one infected member. Neither children with AAE nor their households showed severe COVID-19.

[CDAGS syndrome (craniostenosis, deafness, anal abnormalities and genitourinary malformations with skin rash)]. / Syndrome CDAGS (craniosténose, surdité, anomalie anale et génito-urinaire avec éruption cutanée).

INTRODUCTION: CDAGS syndrome (craniosynostosis, deafness, anal and genitourinary abnormality with rash) has been reported in 8 families of different geographical origins since 1981. No genes have been identified to date. PATIENTS AND METHODS: The patient is a girl born at 40 weeks of amenorrhea after a normal pregnancy. She was born to non-consanguineous parents and there was no significant family history. At birth, she presented craniosynostosis with a form of premature coronal suture. When she was 3 months old, she presented an eczematous facial rash. At 11 months, a skin biopsy showed lichenoid dermatosis with epidermal atrophy associated with ortho- and para-keratotic hyperkeratosis. She had sparse hair, eyelashes and eyebrows. Her initial psychomotor development was normal. No other malformations were observed. At 6 years, she presented pale pink, reticulated, erythematous plaques around healthy bands of skin on her throat and chin. Lesions on the elbows, knees and buttocks were linear and keratotic with no atrophy or telangiectasia. At 7 years, she had learning difficulties and delayed speech. Genetic assessment revealed no abnormalities. DISCUSSION: The specific dermatologic aspect combined with craniosynostosis suggested a possible diagnosis of CDAGS syndrome, even in the absence of urogenital or anal lesions. This syndrome may take numerous different forms. The appearance of porokeratosis previously noted was not found here. The underlying genetic substratum of this syndrome is not known as yet and additional genetic studies should be considered.

Mosaic abnormalities of the skin: review and guidelines from the European Reference Network for rare skin diseases.

BACKGROUND: Cutaneous mosaicism is an area of dermatology in which there has been an explosion of knowledge within the current decade. This has led to fundamental changes in the understanding of the conditions in this field, and to an ongoing paradigm shift in the approach to management of mosaic skin disorders. OBJECTIVES: To lay out the general principles of mosaicism as they are currently understood, summarize the known cutaneous mosaic abnormalities of the skin with associated phenotypic and genotypic information, review the latest trials on targeted therapies and propose guidelines for the general approach to a patient with suspected mosaicism. METHODS: This was a consensus expert review as part of the European Reference Network project (ERN-Skin). CONCLUSIONS: This study provides clinicians with a practical approach to the patient with suspected mosaicism, redefines mosaicism for the modern genetic era, and proposes a new classification system based on genetic mechanism. What's already known about this topic? Cutaneous mosaicism is a complex field of dermatology that encompasses most birthmarks, and many rare syndromes. Some cutaneous patterns are known to be seen in mosaicism. Very few treatment options are available for most mosaic abnormalities of the skin. Recent high-sensitivity genetic techniques have led to an explosion of knowledge about genotype and phenotype in the literature. What does this study add? Expert consensus from the European Reference Network project. Review of knowledge of confirmed mosaic abnormalities of the skin, including cutaneous phenotype, extracutaneous associated features and genotype. Proposed new classification of mosaic abnormalities of the skin by genetic mechanism and therefore inheritance potential. Practical tips on correct sample collection and genetic investigation. Review of trials of targeted therapies. Guidelines for a practical clinical approach to the patient with suspected mosaicism.

Rituximab is an effective treatment in patients with pemphigus vulgaris and demonstrates a steroid-sparing effect.

BACKGROUND: Corticosteroids (CS) with or without adjuvant immunosuppressant agents are standard treatment for pemphigus vulgaris (PV). The efficacy of adjuvant therapies in minimizing steroid-related adverse events (AEs) is unproven. OBJECTIVES: To utilize data collected in a French investigator-initiated, phase III, open-label, randomized controlled trial to demonstrate the efficacy and safety of rituximab and seek approval for its use in PV. METHODS: This was an independently conducted post hoc analysis of the moderate-to-severe PV subset enrolled in the Ritux 3 study. Patients were randomized to rituximab plus 0·5 or 1·0 mg kg-1 per day prednisone tapered over 3 or 6 months, or 1·0 or 1·5 mg kg-1 per day prednisone alone tapered over 12 or 18 months, respectively (according to disease severity). The primary end point was complete remission at month 24 without CS (CRoff) for ≥ 2 months, and 24-month efficacy and safety results were also reported. RESULTS: At month 24, 34 of 38 patients (90%) on rituximab plus prednisone achieved CRoff ≥ 2 months vs. 10 of 36 patients (28%) on prednisone alone. Median total cumulative prednisone dose was 5800 mg in the rituximab plus prednisone arm vs. 20 520 mg for prednisone alone. Eight of 36 patients (22%) who received prednisone alone withdrew from treatment owing to AEs; one rituximab-plus-prednisone patient withdrew due to pregnancy. Overall, 24 of 36 patients (67%) on prednisone alone experienced a grade 3/4 CS-related AE vs. 13 of 38 patients (34%) on rituximab plus prednisone. CONCLUSIONS: In patients with moderate-to-severe PV, rituximab plus short-term prednisone was more effective than prednisone alone. Patients treated with rituximab had less CS exposure and were less likely to experience severe or life-threatening CS-related AEs. What's already known about this topic? Pemphigus vulgaris (PV) is the most common type of pemphigus. Corticosteroids, a standard first-line treatment for PV, have significant side-effects. Although their effects are unproven, adjuvant corticosteroid-sparing agents are routinely used to minimize steroid exposure and corticosteroid-related side-effects. There is evidence that the anti-CD20 antibody rituximab is effective in the treatment of patients with severe recalcitrant pemphigus and in patients with newly diagnosed pemphigus. What does this study add? This study provides a more detailed analysis of patients with PV enrolled in an investigator-initiated trial. Rituximab plus prednisone had a steroid-sparing effect and more patients achieved complete remission off prednisone. Fewer patients experienced grade 3 or grade 4 steroid-related adverse events than those on prednisone alone. This collaboration between academia and industry, utilizing independent post hoc analyses, led to regulatory authority approvals of rituximab in moderate-to-severe PV.

[Alopecia, deformed ear and mental retardation associated with terminal 21q deletion]. / Alopécie, dysplasie auriculaire et déficit intellectuel en lien avec une délétion 21q terminale.

BACKGROUND: Partial 21q monosomy is a rare condition with only a few cases being described in the literature. We report a new case associating congenital alopecia with 21q deletion. PATIENTS AND METHODS: At birth, a female infant presented with diffuse alopecia, atrichia of the eyelashes and eyebrows, and deformed ears. Her development was marked by the appearance of intellectual deficit. Chromosome analysis by karyotype and CGH (comparative genomic hybridization) array revealed ring chromosome 21 with 21q22.3 terminal deletion of 3.6 Mb. The other laboratory examinations were unremarkable, and simply ruled out the main differential diagnoses. Treatment with zinc and Minoxidil® 5% allowed regrowth of lightly pigmented down on the scalp alone. DISCUSSION: A combination of alopecia, deformed ears and mental retardation should suggest a diagnosis of partial 21q monosomy. Alopecia, which is poorly described in this syndrome, seems to be more frequently associated with 21q22.3 terminal involvement.

Epidermolysis bullosa simplex generalized severe induces a T helper 17 response and is improved by apremilast treatment.

BACKGROUND: Epidermolysis bullosa simplex generalized severe (EBS-gen sev) is a genetic disorder caused by mutation in the KRT5 or KRT14 genes. Although it is usually considered a mechanical disease, recent data argue for additional inflammatory mechanisms. OBJECTIVES: To assess the inflammation in the skin of patients with EBS-gen sev. METHODS: A first immunohistochemical retrospective study was performed on frozen skin samples from 17 patients with EBS-gen sev. A second multicentre prospective study was conducted on 10 patients with severe EBS-gen sev. Blister fluid and epidermis were processed for immunochemical analysis and quantitative real-time polymerase chain reaction. Cytokine expression was analysed in blister fluid and compared with that in controls. RESULTS: Histological analysis showed a constant dermal perivascular CD4+ lymphocyte infiltrate in skin biopsies of both blister (n = 17) and rubbed skin (n = 5), an epidermal infiltration of neutrophils and eosinophils in 70% of cases, and increased immunostaining for CXCL9 and CXCL10 in blistering skin. High levels of T helper 17 cytokines were detected in lesional skin. Three adult patients with EBS-gen sev were treated with apremilast, with a dramatic improvement of skin blistering and good tolerance. CONCLUSIONS: Our study demonstrates the importance of inflammation in patients with EBS-gen sev and underlines the key role for T helper 17 cells in its pathogenesis. In addition, this study provides promising new therapeutic approaches for this disabling disorder.

Mosaicism due to postzygotic mutations in women with focal dermal hypoplasia.

Focal dermal hypoplasia (FDH, Goltz syndrome, MIM #305600) constitutes a rare multisystem genetic disorder of the skin, skeleton, teeth and eyes with considerable variation in the clinical features. FDH is transmitted as an X-linked dominant trait and is caused by mutations in PORCN. In male children, hemizygous PORCN mutations are lethal in utero. Around 300 cases have been reported in the literature to date. About 10% of them are male patients presenting with either Klinefelter syndrome (karyotype 47, XXY) or mosaicism of a postzygotic mutation. Here we describe four cases of women with typical features of FDH, in whom a PORCN mutation was found in DNA from affected cutaneous tissue but not in DNA from peripheral blood. This study suggests that mosaicism caused by a postzygotic mutation occurs more often than assumed to date in female patients with FDH. A negative analysis performed on peripheral blood DNA does not exclude the diagnosis of FDH and it is therefore of practical importance to analyse DNA from the affected skin in order to identify low-level mosaicism and thus to improve diagnostic precision. In total, we found two missense variants, one novel indel and one novel splice-site variant. Individuals harbouring postzygotic mosaicism run a risk of transmitting the disorder to their daughters, because the maternal mosaic could also affect the gonads.

Tongue psoriasis: Clinical aspects and analysis of epidemiological associations in 313 children, with a systematic literature review.

BACKGROUND: Little information is available on the prevalence and clinical aspects of tongue involvement in children with psoriasis. The aim was to evaluate the prevalence, clinical aspects and risk factors concerning tongue involvement in children with psoriasis. PATIENTS AND METHODS: This study was carried out in two stages. We performed a multicentre, cross-sectional study in 23 French dermatology centers. All children seen for psoriasis during the one-year study were systematically included. The clinical features of the tongue and of psoriasis were recorded. Association with clinical aspects of psoriasis and comorbidities was evaluated. We then carried out a literature review to evaluate the prevalence of tongue involvement in children with psoriasis and its positive predictive value for psoriasis. A search was conducted in the PUBMED database using the following keywords: "child" and "psoriasis" and ("tongue" or "glossitis" or "migratory glossitis" or "benign migratory glossitis" or "geographic tongue" or "fissured tongue"). RESULTS: 7.7% of the 313 children with psoriasis had tongue involvement. The clinical aspects were geographic tongue (4.2%), fissured tongue (2.8%) and both (0.64%). There was no association between tongue involvement and the clinical characteristics of the children. Two hundred and ninety-five articles were referenced and 3 were analysed. Psoriasis is very rare in cases of tongue abnormalities. CONCLUSION: The prevalence of tongue involvement was 7.7% in children with psoriasis. No clinical or epidemiological association was shown. Tongue involvement does not modify the management of psoriasis. In the literature review it was not possible to evaluate either the prevalence of tongue involvement in psoriasis or the positive predictive value thereof.

Clinical and haemodynamic risk factors associated with discrepancies in lower limb length with capillary malformations: data from the national paediatric French cohort CONAPE.

BACKGROUND: Genetics discoveries have allowed for a better understanding of capillary malformations (CMs) associated with overgrowth syndrome. However, molecular analyses are still not easy to perform or interpret. Other analytical methods are needed. OBJECTIVES: To identify clinical and haemodynamic factors associated with leg length discrepancy (LLD) in children with CMs of the lower limbs. METHODS: Data were obtained from the multicentre French national cohort CONAPE (COhorte Nationale d'enfants atteints d'Angiome Plan de membrE inférieur), from children aged 2-12 years old with CMs of the lower limbs. Clinical characteristics were prospectively collected. Haemodynamic factors were measured by an sonographer who calculated the arterial blood flow (ABF) in both lower limbs. An ABF difference ≥ 50% between the two lower limbs was considered relevant. LLD ≥ 2% was determined by the same radiologist on centralized radiographs. RESULTS: We analysed data at baseline for 96 children. The mean ± SD age was 5·6 ± 3·1 years; 49 (51%) were male; and 14 (15%) showed LLD. In total, 32 patients (33%) had venous anomalies, 13 (14%) lymphatic anomalies and in one child a diagnosis of Parkes Weber syndrome was made. Only an increased circumference above the knee was more frequent with than without LLD (43% vs. 13%, P = 0·02). In all, 10/79 patients (13%) showed a difference in ABF ≥ 50%: four had LLD. The frequency of differences in ABF ≥ 50% was greater with than without LLD [33% (n = 4/12) vs. 9% (n = 6/67), P = 0·04]. CONCLUSIONS: ABF measured by Duplex ultrasonography is a simple, low-cost and noninvasive complementary examination for help in detecting LLD, with a difference of ≥ 50% possibly associated.

Mosaic-activating FGFR2 mutation in two fetuses with papillomatous pedunculated sebaceous naevus.

Papillomatous pedunculated sebaceous naevus (PPSN) has been described as a subtype of sebaceous naevus (SN), typically affecting the scalp and face. In contrast with Schimmelpenning syndrome, no cerebral, ocular or skeletal anomalies have hitherto been reported. We report two unrelated fetuses with PPSN, one with large pink exophytic tumours, the other with minor features but similar microscopic findings. We performed whole-exome sequencing in affected skin tissue from fetus 1, which identified a postzygotic de novo FGFR2 c.1144T>C (p.Cys382Arg) mutation in 34·6% of reads which was absent in the parents' blood. Targeted deep sequencing of FGFR2 confirmed its mosaic status in additional affected skin from fetus 1, and identified the same substitution in 26% of reads in affected skin from fetus 2. FGFR2 p.Cys382Arg is a known somatic driver mutation in human cancer, previously reported to result in activation of RAS signalling. A similar paralogous missense mutation in the transmembrane domain of FGFR3 (p.Gly380Arg) has been reported in keratinocytic epidermal naevi. Our findings define a distinct clinical and molecular subgroup of SN, beside HRAS or KRAS-related SN, and expand the spectrum of mosaic skin conditions associated with receptor tyrosine kinase mutations.

Active tuberculosis in psoriasis patients treated with TNF antagonists: a French nationwide retrospective study.

BACKGROUND: There is limited information about active tuberculosis (TB) occurring in psoriasis patients treated with Tumor necrosis factor (TNF) antagonists. OBJECTIVE: To describe the clinical characteristics of TB in psoriasis patients treated with TNF antagonists. METHODS: Nationwide retrospective study of psoriasis patients having experienced TB. Cases of TB were collected via three methods: search in the national pharmacosurveillance database, questionnaire to members of the French psoriasis research group, the college of French dermatology professors. We collected demographic data, TNF antagonist used, screening for latent tuberculosis infection, median time between TNF antagonists introduction and first symptoms, tests used for diagnosing TB infection, clinical features of tuberculosis and outcome. RESULTS: Eight centres reported 12 cases of TB between 2006 and 2014. They were nine men and three women with mean age of 49 years. All patients had adequate screening for latent tuberculosis. Three patients had stayed in endemic areas, three reported contact with a patient with TB. Tuberculosis presentation was extrapulmonary in 10 patients. Seven patients were treated with infliximab, four with adalimumab and one with certolizumab. The median time between TNF antagonist introduction and first symptoms of tuberculosis was 23.4 weeks (2-176). Six of the 12 patients had a positive direct examination and/or positive culture for Mycobacterium tuberculosis. Histological samples of affected organs taken from seven patients showed granulomatous inflammation in six, with caseating necrosis in five. Two of the 12 patients died of disseminated TB. CONCLUSION: This study shows tuberculosis in patients treated with TNF antagonists still occurs despite adherence to tuberculosis prevention guidelines. Prophylactic measures do not fully prevent the occurrence of tuberculosis. Rapid initiation of effective anti-tuberculosis treatment is important even in patients with negative mycobacteriological examination presenting with suggestive symptoms and organ involvement.

[Impact of sex and age on the clinical and epidemiological aspects of childhood psoriasis: Data from a French cross-sectional multicentre study]. / Impact de l'âge et du sexe sur les aspects cliniques et épidémiologiques du psoriasis de l'enfant. Données d'une étude transversale multicentrique française.

BACKGROUND: The prevalence of childhood psoriasis is estimated at between 0.4% and 0.7%. Clinical aspects of the diseases depend on age. The aim of this study was to investigate the clinical aspects of psoriasis according to age and sex. PATIENTS AND METHODS: A cross-sectional, multicentre study of children with psoriasis was performed by investigators belonging to the Research Group of the French Society of Paediatric Dermatology. The study was conducted from April 2012 to March 2013. Inclusion criteria were age less than 18 years and clinical diagnosis of psoriasis. The children were classified into 3 groups by age: infants: <2 years; children: ≥2 years and <13 years; adolescents≥13 years. The information collected included demographic data, clinical, epidemiological, and therapeutic aspects of the psoriasis, as well as analysis of comorbidities. RESULTS: Three hundred and thirteen children were included: 27 (8.6%) infants, 207 (66.1%) children, and 79 (25.2%) adolescents. Plaque psoriasis was the most frequent clinical type of psoriasis seen in children and adolescents (>41%), but it accounted for only 25.9% of psoriasis of infants (P<0.0001). Napkin psoriasis (37.0%) and inverse psoriasis (22.2%) were the most common forms of psoriasis seen in infants and were described significantly more frequently in this group than in the two other groups (P<0.003). Nail involvement was more common in adolescents (37.2%, P=0.03) and children (32.9%) than in infants (14.8%) and affected boys more than girls (43.6% vs 22.0%, P<0.0001). Girls presented scalp psoriasis more frequently (17.7% vs 8.7%, P=0.02). Local vitamin-D treatment and systemic therapies were used more frequently in children and adolescents than in infants. There was no significant difference for treatment use, including for acitretin, according to gender. DISCUSSION: Plaque psoriasis was the most common clinical type of psoriasis in children but affected less than 50% of the children. Age had a significant impact on extra-cutaneous skin disorders and on treatment used, while sex had little incidence. The frequency of comorbidities was not affected by age. CONCLUSION: Childhood psoriasis thus presents specific characteristics dependent on the age of the child. The results of studies exclusively dealing with adults cannot be extrapolated to children.