Transmission electron microscopy of pili annulati

Abstract Background: Little is known about the ultrastructure of pili annulati. Objectives: To examine with transmission electron microscopy affected hairs of a family, whose diagnosis had been confirmed in five individuals with scanning electron microscopy, which showed surface undulations with ''curtain-like'' folding of the hair cuticula and to compare the findings with normal control. Methods: Hairs of two affected patients and one control were embedded in resin and cut lengthwise to produce ultra-thin sections. Results: The normal hair showed a parallel arrangement of dark lines associated with less electron-dense wide bands. Small cavities could be observed, mostly in the dark lines, affected hairs had a large number of cavities, associated or not with the insertion of melanosomes and loss of parallelism of the dark lines. Higher magnification showed a significant loss of this parallelism, resembling ''wood grooves''. Widened dark lines were observed in some areas. Study limitations: Only a few hairs were examined. Conclusions: The present results suggest that the microcanaliculi of the hair surface, easily found with scanning electron microscopy, may be secondary not only to the cavities seen in the sections but also to the disorder of proteins that form this region, demonstrated by the changes of the cortex dark lines.

Scanning electron microscopy of panitumumab-induced eyelash and hair alterations - Pili canaliculi

Abstract Panitumumab is a monoclonal antibody against the epidermal growth factor receptor used in metastatic colorectal cancer; in addition to tumor cells, it acts on epidermal keratinocytes and on the outer root sheath and presents skin toxicity in up to 90% of cases. A scanning electron microscope was used to examine the eyelashes and hairs of a 65-year-old patient with eyelash trichomegaly, curly hair, and paronychia undergoing treatment with panitumumab. Grooving in the hair shafts were identified, which were more evident in the eyelashes. Similar to oral epidermal growth factor inhibitors (erlotinib and gefitinib), panitumumab can cause acquired pili canaliculi.

McCune-Albright syndrome - A case report with transmission electron microscopy

Abstract McCune - Albright syndrome is a genetic disease with cutaneous mosaicism caused by post-zygotic activating mutations in GNAS locus, it has a triad of fibrous bone dysplasia, café-au-lait macules and precocious puberty. We examined a 22-year-old female patient with café au lait spot in right side of the abdomen, with a chessboard - like distribution, extending to right thigh with geographical contours, she has also an ovarian cyst, scoliosis and truncal obesity. Biopsies were taken from the hyperpigmented area and processed for light microscopy and for transmission electron microscopy. Light microscopy showed increased melanin pigment with HE staining. Immunohistochemistry with melanocytic markers (HMB-45 and Melan-A) revealed a normal number of melanocytes. Transmission electron microscopy demonstrated normal epidermal structures, such as desmosomes, cytokeratin filaments and hemidesmosomes. With high magnifications an irregular melanossomal contour was seen, with some indentations in their outline.

Case for diagnosis. Radiotherapy-induced pemphigus vegetans

Abstract A 73-year-old male patient developed a poorly differentiated squamous cell carcinoma in the anal canal nine months ago. He was treated with two cycles of 5-fluorouracil and cisplatin and concomitant radiotherapy (6 MeV linear photon accelerator, total dose of 54 Gy), with complete remission. Since forty-five days he presentes a painful perianal and intergluteal erosion with circinate pustular borders. Light microscopy showed pseudoepitheliomatous hyperplasia of the epidermis with microabscesses of inflammatory cells (neutrophils and eosinophils) and acantholytic keratinocytes . Indirect immunofluorescence was positive for IgG, with an intercellular pattern, 1:80 titer. The diagnosis of radiotherapy-induced pemphigus vegetans was established and there was significant regression with oral prednisone (40 mg) and topical betamethasone.

Ultrastructural aspects of the skin in lipoid proteinosis (Urbach-Wiethe disease)

Abstract Lipoid proteinosis is a rare autosomal recessive disease, characterized by hyaline deposits of PAS-positive material in tissues due to mutations in the ECM1 gene. This study evaluated the ultrastructure of the skin of a 6-year-old child affected by this condition. The light microscopy identified PAS-positive hyaline deposits, which were more intense in the papillary dermis. Scanning electron microscopy of the dermis showed a compact papillary dermis and fibrillar deposits in the middle dermis. Transmission electron microscopy clearly showed the deposition of fibrillar material in the dermis, forming clusters adherent to elastic fibers, between the collagen bundles and the collagen fibers, and also filling up the cytoplasm of dermal fibroblasts.

Recurrent aphthous stomatitis in 18-year-old adolescents - Prevalence and associated factors: a population-based study

Abstract: Background: Recurrent aphthous stomatitis is a painful disorder of unknown etiology. It is among the most common oral mucosal lesions with high prevalence among young adults. Objectives: To conduct a population-based study with 18-year-old army recruiters to assess its prevalence and associated factors in male adolescents. Methods: Interview during clinical examination in the army. Results: In this group (2,427 interviewed adolescents) there was a RAS prevalence of 24.9%. Smoking, herpes labialis and socioeconomic status correlated with the outcome. Study Limitations: only male adolescents were interviewed. Conclusions: Our results showed high prevalence of RAS; association with higher economic level and herpes simplex was found. Protective effect of smoking was confirmed.

Ultrastructural aspects of pseudoxanthoma elasticum

Abstract: We report the ultrastructural findings in a case of a 72-year-old black woman with confluent yellowish papules in the cervical region. She had no comorbidities. Ophthalmological examination, electrocardiogram, and echocardiogram were normal. Hematoxylin-eosin staining of the affected skin showed strong alterations in the mid-dermis with irregular clumps of eosinophilic material and loss of the normal parallel arrangement of collagen bundles. Orcein staining revealed that the elastic fibers lost their normal linear configuration, showing clump fragmentation, sometimes forming square structures. Transmission electron microscopy showed aberrant elastic fibers with an irregular outline and heterogenic inner structures. We also observed small elastic fibers. Collagen fibers showed a normal structure with irregular distribution. Scanning electron microscopy revealed important disorganization of collagen fibers and small stone-like deposits measuring around 5 µm associated with bigger structures ranging from 10-16 µm. Higher magnification revealed that these small stone-like structures were sometimes polyhedral-shaped or squared.

Infantile generalized hypertrichosis caused by topical minoxidil

Abstract Rare cases of hypertrichosis have been associated with topically applied minoxidil. We present the first reported case in the Brazilian literature of generalized hypertrichosis affecting a 5-year-old child, following use of minoxidil 5%, 20 drops a day, for hair loss. The laboratory investigation excluded hyperandrogenism and thyroid dysfunction. Topical minoxidil should be used with caution in children.

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.

Dissatisfaction and acne vulgaris in male adolescents and associated factors

BACKGROUND: Acne vulgaris has high prevalence, disturbing quality of life during adolescence. OBJECTIVES: To measure dissastifaction and acne in 18-year-old male individuals and its associated factors. METHODS: A questionnaire was applied by trained interviewers to all boys during selection for the military service. Dissatisfaction and acne was evaluated using a self-administered face scale. Facial, prestrernal and dorsal acne were evaluated separately. RESULTS: A total of 2,200 adolescents, aged 18 years, were interviewed. Among these, 1,678 had acne on the face and 974 (54.05%) showed some degree of dissatisfaction. Regarding the impact of acne located on the chest, 326 out of 686 adolescents (47.52%) reported dissatisfaction. For acne located on the back, 568 out of 1,103 affected individuals (51.50%) showed dissatisfaction. Facial / dorsal acne and dissatisfaction were statistically associated with lower income, lower education levels and with non-whites. Presternal acne and dissatisfaction were statistically asssociated with lower income and lower education levels. CONCLUSION: This population-based study found a high prevalence of acne on the face, back and chest, with high rates of dissatisfaction. .

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.