Pili canaliculi as manifestation of giant axonal neuropathy

Abstract Giant axonal neuropathy is a rare autosomal recessive neurodegenerative disease. The condition is characterized by neurons with abnormally large axons due to intracellular filament accumulation. The swollen axons affect both the peripheral and central nervous system. A 6-year old female patient had been referred to a geneticist reporting problems with walking and hypotonia. At the age of 10, she became wheelchair dependent. Scanning electron microscopy of a curly hair classified it as pili canaliculi. GAN gene sequencing demonstrated mutation c.1456G>A (p.GLU486LYS). At the age of 12, the patient died due to respiratory complications. Dermatologists should be aware of this entity since hair changes are considered suggestive of GAN.

Pitted keratolysis

Abstract Pitted keratolysis is a skin disorder that affects the stratum corneum of the plantar surface and is caused by Gram-positive bacteria. A 30-year-old male presented with small punched-out lesions on the plantar surface. A superficial shaving was carried out for scanning electron microscopy. Hypokeratosis was noted on the plantar skin and in the acrosyringium, where the normal elimination of corneocytes was not seen. At higher magnification (x 3,500) bacteria were easily found on the surface and the described transversal bacterial septation was observed.

Scanning electron microscopy of superficial white onychomycosis

AbstractSuperficial white onychomycosis is characterized by opaque, friable, whitish superficial spots on the nail plate. We examined an affected halux nail of a 20-year-old male patient with scanning electron microscopy. The mycological examination isolated Trichophyton mentagrophytes. Abundant hyphae with the formation of arthrospores were found on the nail's surface, forming small fungal colonies. These findings showed the great capacity for dissemination of this form of onychomycosis.

Scanning electron microscopy of the collodion membrane from a self-healing collodion baby

AbstractSelf-healing collodion baby is a well-established subtype of this condition. We examined a male newborn, who was covered by a collodion membrane. The shed membrane was examined with scanning electron microscopy. The outer surface showed a very compact keratin without the normal elimination of corneocytes. The lateral view of the specimen revealed a very thick, horny layer. The inner surface showed the structure of lower corneocytes with polygonal contour. With higher magnifications villous projections were seen in the cell membrane.

Three-dimensional aspects of superficial disseminated porokeratosis with scanning electron microscopy

The three-dimensional findings of the surface and from a cross section from a case of disseminated superficial porokeratois using scanning electron microscopy are reported. On the surface of the skin, irregular keratin with a serpiginous distribution was seen. A gross aspect of keratin in the hyperkeratotic wall was also observed and compared to the normal area, in which the release of corneocytes seemed normal. The cross-sectional imaging easily identified the cornoid lamella, with compact keratin surrounded by normal stratum corneum.

Scanning electron microscopy of tinea nigra

Tinea nigra is a rare superficial mycosis caused by Hortaea werneckii. This infection presents as asymptomatic brown to black maculae mostly in palmo-plantar regions. We performed scanning electron microscopy of a superficial shaving of a tinea nigra lesion. The examination of the outer surface of the sample showed the epidermis with corneocytes and hyphae and elimination of fungal filaments. The inner surface of the sample showed important aggregation of hyphae among keratinocytes, which formed small fungal colonies. The ultrastructural findings correlated with those of dermoscopic examination - the small fungal aggregations may be the dark spicules seen on dermoscopy - and also allowed to document the mode of dissemination of tinea nigra, showing how hyphae are eliminated on the surface of the lesion.

Comparative scanning electron microscopy of bullous diseases

The purpose of this study is to compare scanning electron microscopy findings of the blister roof in three distinct bullous diseases: one intraepidermal acantholytic (pemphigus foliaceus); one due to hemidesmosomal dysfunction (bullous pemphigoid); and one secondary to anchoring fibril dysfunction - type VII collagen (dystrophic epidermolysis bullosa). In pemphigus foliaceus, acantholytic phenomena were readily demonstrated. In bullous pemphigoid, the epidermis had a solid aspect. In dystrophic epidermolysis bullosa a net was seen in the blister roof.

Scanning electron microscopy of a blister roof in dystrophic epidermolysis bullosa / Microscopia eletronica de varredura do teto de uma bolha de epidermolise bolhosa distrofica

In dystrophic epidermolysis bullosa the genetic defect of anchoring fibrils leads to cleavage beneath the basement membrane, with its consequent loss. We performed scanning electron microscopy of an inverted blister roof of a case of dystrophic epidermolysis bullosa, confirmed by immunomapping and gene sequencing. With a magnification of 2000 times a net attached to the blister roof could be easily identified. This net was composed of intertwined flat fibers. With higher magnifications, different fiber sizes could be observed, some thin fibers measuring around 80 nm and thicker ones measuring between 200 and 300 nm.

Na epidermólise bolhosa distrófica, o defeito genético das fibrilas ancorantes leva à clivagem abaixo da membrana basal, com sua consequente perda. Realizamos microscopia eletrônica de varredura do teto invertido de uma bolha de um caso de epidermólise bolhosa distrófica, cujo diagnóstico foi confirmado com imunomapeamento e com sequenciamento gênico. Com uma ampliação de 2.000 vezes, pôde ser facilmente identificada uma rede ligada ao teto da bolha. Essa rede era composta por fibras achatadas e entrelaçadas. Com grandes aumentos, fibras de diferentes tamanhos puderam ser observadas: algumas finas, medindo cerca de 80 nm, e outras mais largas, medindo entre 200 nm e 300 nm.

Scanning electron microscopy of acantholysis in pemphigus foliaceus / Microscopia eletrônica de varredura da acantólise no pênfigo foliáceo

We performed scanning electron microscopy of an inverted blister roof in a case of pemphigus foliaceus. The loss of intercellular adherence could be easily seen with low magnification. The acantholytic keratinocytes displayed an irregular and sometimes polygonal contour. Round cells, typically seen in light microscopy, were also observed. The examination of a blister roof allows ultrastructural documentation of the acantholytic changes.

Realizamos microscopia eletrônica de varredura do teto invertido de uma bolha de um caso de pênfigo foliáceo. Com pequeno aumento, a perda da adesão intercelular pôde ser vista claramente. Os queratinócitos acantolíticos demostraram um contorno irregular, algumas vezes poligonal. Células arredondadas, como vistas tipicamente na microscopia óptica, também foram observadas. O exame de um teto de bolha permite uma documentação ultraestrutural das alterações acantolíticas.

Scanning electron microscopy of lichen sclerosus / Microscopia eletrônica de varredura do líquen escleroso

Lichen sclerosus is an acquired inflammatory condition characterized by whitish fibrotic plaques, with a predilection for the genital skin. We performed scanning electron microscopy of the dermis from a lesion of lichen sclerosus. Normal collagen fibers could be easily found in deeper layers of the specimen, as well as the transition to pathologic area, which seems homogenized. With higher magnifications in this transitional area collagen fibers are adherent to each other, and with very high magnifications a pearl chain aspect became evident along the collagen fibers. In the superficial dermis this homogenization is even more evident, collagen fibers are packed together and round structures are also observed. Rupture of collagen fibers and inflammatory cells were not found. These autoimmune changes of the extracellular matrix lead to the aggregation of immune complexes and/or changed matrix proteins along the collagen fibers, the reason why they seem hyalinized when examined by light microscopy.

O líquen escleroso é uma afecção inflamatória caracterizada por placas esbranquiçadas fibróticas ocorrendo preferentemente na pele genital. Realizamos exame com microscópio eletrônico de varredura da derme de uma lesão de líquen escleroso. Ao exame as fibras colágenas normais puderam ser facilmente identificadas, bem como a transição para a área alterada, a qual aparece homogeneizada. Nessa área as fibras parecem aderidas umas às outras e com aspecto em colar de pérolas. Na derme superficial essa homogeneização é ainda mais evidente, com as fibras bem aderidas e ainda com as estruturas arredondadas. Ruptura das fibras e células inflamatórias não foram observadas. Os fenômenos autoimunes que ocorrem na matriz extracelular nessa enfermidade devem levar à agregação de imunocomplexos e/ou proteínas alteradas nas fibras colágenas, por essa razão elas aparecem hialinizadas na microscopia óptica.

Clinical variability in dystrophic epidermolysis bullosa and findings with scanning electron microscopy / Variabilidade clínica em epidermólise bolhosa distrófica e achados de microscopia eletrônica de varredura

In dystrophic epidermolysis bullosa, the genetic defect of anchoring fibrils leads to cleavage beneath the basement membrane and its consequent loss. A 46 year-old female patient presented blisters with a pretibial distribution associated with nail dystrophy. Her two children had hyponychia and anonychia, which affected all toe nails and the thumb, forefinger and middle finger. DNA sequencing identified in exon 75 of COL7A1 gene a pathologic mutation: c.6235G>A (p.Gly2079Arg). Immunomapping of a blister demonstrated collagen IV (basal membrane) in the blister roof and collagen VII in its floor, confirming dystrophic epidermolysis bullosa. Scanning electron microscopy of an inverted blister showed net-forming collagen attached to the blister roof . The variability found in this family has already been reported and confirms, on a clinical basis, the nail subtype as a dystrophic variant.

Na epidermólise bolhosa distrófica, o defeito genético das fibrilas de ancoragem leva à clivagem abaixo da membrana basal com sua consequente perda. Uma paciente de 46 anos apresentava bolhas pré-tibiais associadas à distrofia ungueal. Seus dois filhos apresentavam hipo e anoníquia, afetando todas as unhas dos pododáctilos e dos primeiros, segundos e terceiros quirodáctilos. O sequenciamento de DNA identificou no exon 75 do gene COL7A1 uma mutação patológica: c.6235G>A (p.Gly2079Arg). O imunomapeamento identificou o colágeno IV no teto e colágeno VII no assoalho de uma bolha , confirmando o diagnóstico de epidermólise bolhosa distrófica. A microscopia eletrônica de varredura de um teto invertido de bolha demonstrou rede de colágeno aderida ao mesmo. A variabilidade clínica encontrada nessa família já foi escrita e confirma, que o subtipo ungueal das epidermólises bolhosas é uma forma distrófica.