Epidermolysis bullosa pruriginosa in association with lichen planopilaris

Epidermolysis Bullosa: Two rare case reports of COL7A1 and EBS-GEN SEV KRT14 variants with review of literature

EPIDERMOLYSIS

Bullosa is a rare hereditary skin condition that causes blisters. Genes encoding structural proteins at or near the dermal-epidermal junction are mutated recessively or dominantly, and this is the primary cause of EB. Herein, two Chinese boys were diagnosed with the condition, each with a different variant in a gene that serves as a reference for EB genetic counseling. Skincare significantly impacted their prognosis and quality of life.

CASE PRESENTATION

Two Chinese boys, with phenotypically normal parents, have been diagnosed with distinct blister symptoms, one with Dominant Dystrophic Epidermolysis Bullosa and the other with a severe form of Epidermolysis Bullosa Simplex. The first patient had a G-to-A variant in the COL7A1 allele, at nucleotide position 6163 which was named "G2055A". The proband is heterozygous for Dystrophic Epidermolysis Bullosa due to a COL7A1 allele with a glycine substitution at the triple helix domain. A similar variant has been discovered in his mother, indicating its potential transmission to future generations. Another patient had severe Epidermolysis Bullosa Simplex with a rare c.377T > A  variant resulting in substitution of amino acid p.Leu126Arg (NM_000526.5 (c.377T > G, p.Leu126Arg) in the Keratin 14 gene. In prior literature, Keratin 14 has been associated with an excellent prognosis. However, our patient with this infrequent variant tragically died from sepsis at 21 days old. There has been a reported occurrence of the variant only once.

CONCLUSION

Our study reveals that Epidermolysis Bullosa patients with COL7A1 c.6163G > A and KRT14 c.377T>A variants have different clinical presentations, with dominant forms of Dystrophic EB having milder phenotypes than recessive ones. Thus, the better prognosis in the c.6163G > A patient. Furthermore, c.377T>A patient was more prone to infection than the patient with c.6163G>A gene variant. Genetic testing is crucial for identifying the specific variant responsible and improving treatment options.

Pathogenesis and clinical features of alopecia in epidermolysis bullosa: A systematic review

BACKGROUND

Epidermolysis bullosa (EB) is a group of rare genetic skin diseases characterized by the gene mutations encoding adhesion proteins within the skin. These adhesion proteins are also present in normal hair follicles. Anecdotally, there have been reports of scalp alopecia as a complication of EB and there are scattered cases in the literature, but alopecia has generally been overlooked in severe blistering diseases because it is regarded as a cosmetic issue. Therefore, there is no consensus about the natural history and clinical manifestations of alopecia in EB to allow potential intervention.

OBJECTIVES

To review the current literature detailing the pathogenesis and clinical presentations of alopecia in EB patients.

METHODS

Relevant human studies were searched in Medline, PubMed, and EMBASE electronic databases up to October 2018.

RESULTS

Only 15 reports detailed 29 EB patients with demographic and clinical manifestations of alopecia. Vertical biopsy sections were the most common method of alopecia diagnosis, and the most common pattern was patchy scalp alopecia (45%) followed by diffuse alopecia (41%). The most robust finding was nonspecific scarring alopecia in all dystrophic EB (DEB) patients and nonspecific nonscarring alopecia in most patients with EB simplex (EBS).

CONCLUSIONS

Hair abnormalities observed in EB are of variable severity despite there being no universal validated alopecia scoring system, with alopecia occurring secondary to blistering, or in areas prone to trauma.

Therapeutic management of classic lichen planopilaris: a systematic review

Several treatment strategies have been proposed in classic lichen planopilaris (LPP), although no gold standard therapeutic approach has been recognized so far due to the variable and, sometimes, contradictory results reported in the literature, as well as due to the lack of guidelines and randomized controlled trials. In the present review, we sought to provide an updated overview on the treatment of classic LPP by analyzing the level of evidence of published studies, also proposing a possible therapeutic strategy according to the findings highlighted in this systematic review.

Treatment of frontal fibrosing alopecia and lichen planopilaris: a systematic review

Frontal fibrosing alopecia (FFA) is a primary lymphocytic cicatricial alopecia with characteristic clinical pattern of progressive frontotemporal hairline recession, perifollicular erythema and hyperkeratosis and symptoms of itch and burning, occurring mainly in post-menopausal women. FFA is considered a subtype of lichen planopilaris (LPP), based on their identical histopathology. Currently, no evidence-based treatment is available for FFA. Our aim was to determine the effectiveness of available treatment options for FFA, and to identify promising treatment options for future studies. For this, literature search was conducted to find all primary studies on the treatment of FFA and LPP. From the primary studies, data were subtracted and analysed. No randomized controlled trials were found, and one controlled trial. Treatment of 114 patients is described in the literature. They received 10 different regimes, of which oral 5-alpha-reductase inhibitors were provided most often, resulting in good clinical response in 45% of them. Hydroxychloroquine resulted in good clinical response in 30% of the 29 treated patients. Topical corticosteroid preparations are ineffective in FFA. The remaining treatments were all reported in less than 10 patients. For the treatment of LPP, topical corticosteroid preparations are the first line of treatment, followed by oral cyclosporine and systemic corticosteroids, although they are characterized by a high relapse rate. Summarizing, there is currently no effective treatment of FFA, the most effective being oral 5-alpha-reductase inhibitors that possibly affect the accompanying androgenetic alopecia. We argue that oral cyclosporine A might be a good candidate for future studies on the treatment of FFA.

An incompletely penetrant novel mutation in COL7A1 causes epidermolysis bullosa pruriginosa and dominant dystrophic epidermolysis bullosa phenotypes in an extended kindred

Epidermolysis bullosa pruriginosa (EBP) is a rare subtype of dystrophic epidermolysis bullosa (DEB) characterized by intense pruritus, nodular or lichenoid lesions, and violaceous linear scarring, most prominently on the extensor extremities. Remarkably, identical mutations in COL7A1, which encodes an anchoring fibril protein present at the dermal-epidermal junction, can cause both DEB and EBP with either autosomal dominant or recessive inheritance. We present one family with both dystrophic and pruriginosa phenotypes of epidermolysis bullosa. The proband is a 19-year-old Caucasian woman who initially presented in childhood with lichenoid papules affecting her extensor limbs and intense pruritus consistent with EBP. Her maternal grandmother saw a dermatologist for similar skin lesions that developed without any known triggers at age 47 and mostly resolved spontaneously after approximately 10 years. The proband's younger brother developed a small crop of pruritic papules on his elbows, dorsal hands, knees, and ankles at age 13. Her second cousin once removed, however, reported a mild blistering disease without pruritus consistent with DEB. Genetic sequencing of the kindred revealed a single dominant novel intron 47 splice site donor G>A mutation, c.4668 + 1 G>A, which we predict leads to exon skipping. Incomplete penetrance is confirmed in her clinically unaffected mother, who carries the same dominant mutation. The wide diversity of clinical phenotypes with one underlying genotype demonstrates that COL7A1 mutations are incompletely penetrant and strongly suggests that other genetic and environmental factors influence clinical presentation.