Dermatologic manifestations in paediatric neurofibromatosis type 2: a cross sectional descriptive multicentric study

Background

Neurofibromatosis type 2 (NF2) is characterized by bilateral vestibular schwannoma (VS) more often in adults but a severe paediatric form with multiple neurological tumours is also described. In this population, a early diagnosis is important to prevent the onset of neurological complications but is difficult, particularly without a familial history. Cutaneous manifestations, which may precede VS or neurological tumours by several years, may contribute to an early diagnosis, but specific studies are lacking. The objective of this study was to characterize cutaneous manifestations of NF2 in a paediatric population.

Results

This observational, descriptive and multicentric study was conducted from April 2019 to April 2020 in seven academic French hospitals. We included patients ≤ 18 years old who fulfilled the Manchester diagnostic criteria or had a pathogenic mutation identified in the NF2 gene. All patients underwent a dermatological examination guided by a standardized questionnaire. 21 children were included, of whom 20 had at least one skin tumour (mean number 5 ± 4.6 [range 0–15]), which led to a diagnosis in four cases. In the other 17 cases, the diagnosis of NF2 was based on neurosensory complications (n = 10), family screening (n = 4) or ocular signs (n = 3). Before the NF2 diagnosis, 15 children had at least one “undiagnosed” cutaneous tumour that did not lead to a specific management. Patients’ dermatological examination also revealed < 6 non specific café au lait macules (n = 15), hypopigmented macules (n = 12) with more than 3 lesions in 4 cases, and purple reticulated macules of the trunk (n = 4).

Conclusion

Dermatological lesions are frequent and early in children with NF2 but rarely lead to the diagnosis. Cutaneous schwannomas are the most frequent but are often underdiagnosed. Café au lait macules are frequent, but atypical and mostly in small numbers. Multiple hypopigmented macules seem suggestive although inconsistent. The sensitivity of reticulated capillary malformation-like lesions remains to be assessed by further studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02379-6.

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.

[Atypical onset of Churg and Strauss syndrome in a child]

We report the case of a 13-year-old boy who had been treated since the age of 6 for moderate asthma. Except asthma, his past medical history was uneventful. The patient was referred for the sudden onset of bilateral leg edemas with peripheral purpuric lesions. Blood tests showed increased blood eosinophilia (9000/mm(3)) with no fever. The antineutrophil cytoplasmic antibodies (ANCA) were negative. The skin biopsy showed extensive ischemic subcutaneous necrosis related to necrotizing vasculitis. The general secondary symptoms occurred with multiorgan involvement (pulmonary infiltrates, peripheral neuropathy, gastrointestinal tract symptoms, and arthralgia). Genital infiltration was also noted. The child's general health was preserved. Neither cardiac nor renal involvement were found. The patient showed favorable clinical progression after oral prednisone therapy.

[Pilar dysplasias]

Pilar dysplasias are congenital or acquired disorders, they are characterized by hair abnormalities in color, density, length and structure. Optic microscopy and polarized light microscopy analysis of piliary shafts provides important informations and contribute to the diagnosis of complex syndromes. Many pathological profiles can be visualized, some are specific, other are not. Some authors use a particularly convenient classification including 3 groups: in the first, piliary shaft abnormalities are isolated, in the second the abnormalities correspond to complex syndromes, and in the third they are associated with various malformations. Based on some clinical cases, we will describe various types of pilar dysplasias and we present recent advances, particularly in genetics.

[Xerosis]

The clinical characteristic of xerosis is rough or coarse skin. Physiopathologically, the structure of the stratum corneum is modified and abnormalities in keratinization, proliferation, surface lipid, water metabolism and also pH and sebum exist. There are two forms of xerosis: dry skin forms and ichtyosis or ichtyosis-like forms. Xerosis has many etiologies including external aggression, senescence, drugs, infection, atopy, deficiencies, malignant diseases, endocrine affections, eating disorders and renal failure in dialyzed patients. It provokes cutaneous discomfort and unaesthetic appearance that justify appropriate treatment. Treatment is essentially local, symptomatic and must be accompanied by general measures. Many products include moisturizers and emollients (keratolytics: salicylic acid, urea and alpha-hydroxy acid).

[Drug hypersensitivity syndrome to valproic acid]

BACKGROUND

Drug-induced hypersensitivity syndrome is an uncommon but potentially life-threatening idiosyncratic drug reaction. It is usually due to aromatic anti-convulsants. We report the second case induced by sodium valproate, a non-aromatic anticonvulsant.

CASE REPORT

A 28-year-old woman was treated with sodium valproate for 5 weeks. She suddenly developed a generalized maculo-papulous eruption with fever, node enlargement, hypereosinophilia and altered liver function.

DISCUSSION

Drug-induced hypersensitivity is rarely induced by valproic acid. The time-course and positive patch tests using the diluted drug establish the diagnosis.

Efficient in vitro regeneration of leek (Allium ampeloprasum L.) via flower stalk segments

A new simple, efficient and rapid in vitro method for mass clonal propagation of leek (Allium ampeloprasum L.) plants, using small (5 mm) flower stalk (peduncle) explants, was established. Adventitious shoots were produced from single subepidermal cells. A wide variation in the percentage of regenerating explants and number of regenerated shoots per explant between individual plants within one cultivar was observed. The concentration of the growth regulators 6-benzylaminopurine and α-naphthalene-acetic acid influenced the percentage of regenerating explants and the average number of regenerated shoots per explant. A combination of 10 mg.l(-1) 6-benzylaminopurine and 10 mg.l(-1) α-naphthalene-acetic acid, resulted in a maximum percentage of regenerating explants and a high average number of regenerated shoots per explant. The percentage of regenerating explants and the average number of regenerated shoots per explant decreased with increasing flower stalk length (age). The basal explants gave both the highest percentage of regenerating explants and average number of regenerated shoots per explant. An average of 300 shoots per flower stalk was obtained for all plants, making this new in vitro method a powerful tool in hybrid leek breeding.