Histopathologic Changes of the Esophagus in Duchenne Muscular Dystrophy.

Duchenne muscular dystrophy (DMD) is characterized by progressive systemic muscle wasting, leading to respiratory paralysis and early death. This X-linked disease is caused by DMD mutations, encoding dystrophin.1 There is little information regarding gastrointestinal abnormalities in patients with DMD. However, since the esophageal wall includes smooth and skeletal muscle it is also vulnerable to suffering the effects of muscle wasting in patients with DMD. After finding dyskeratosis and parakeratosis restricted to the proximal and middle esophagus with distal sparing in an 18-year-old patient with DMD, we performed an archive search of a large academic hospital and identified four additional patients with DMD who had also undergone esophageal biopsy. The patients consisted of five boys, ranging from 7 to 19 years of age. Esophageal injury was present in two patients, consisting of mild esophagitis in one, and spongiosis with dyskeratosis and parakeratosis in another. These patients were both older and had been diagnosed with DMD for greater than 15 years, while the three patients with histologically normal biopsies were younger and been diagnosed with DMD for 7, 9, and 13 years, respectively. Although the data is limited and the changes are subtle, they can be explained by the underlying muscular dystrophy pathophysiology.

Cytologic atypia of benign inflammatory versus neoplastic cutaneous squamous lesions.

BACKGROUND: Cytologic atypia encompasses several features of abnormal cellular morphology. We sought to quantify these features in benign and premalignant/malignant squamous cell lesions to better characterize criteria for malignancy. METHODS: We conducted a rater-blinded observational study in which histopathology slides were evaluated under light microscopy, and the presence and relative quantity of 24 distinct cytological features were recorded, along with respective diagnoses. Each slide was evaluated, and the ratings were recorded and analyzed. RESULTS: The most helpful findings, whose presence in high numbers indicates an increased likelihood that the tissue sample is premalignant/malignant, were: (1) pleomorphic parakeratosis; (2) pleomorphic nuclei in the epithelium; (3) irregular nuclei; (4) thick refractile nuclear envelope; (5) presence of nuclear hyperchromasia (dark gray); (6) peripheral nucleoli; and (7) nucleolar stems. Higher values of round or oval nuclear shape and vesicular nuclei increase the likelihood that the tissue sample is benign. CONCLUSIONS: Certain nuclear features have a higher association with premalignancy/malignancy and may guide histologic evaluation of a given lesion. These findings can be used in combination with architectural features and clinical history to add to a complete diagnostic picture.

Photodynamic Therapy, a successful treatment for granular parakeratosis.

Granular parakeratosis is characterized by variably hyperkeratotic brownish papules or plaques, mostly found on flexures. Different treatments have been suggested with variable results. We present a series of 3 cases successfully treated with one session of methyl-aminolevulinate photodynamic therapy, showing resolution of the lesions and symptoms within less than 2 weeks, as a potentially new, safe and effective therapeutic option.

Spiny keratoderma: A review of case reports and histopathological descriptions.

Spiny keratoderma (SpK) is a rare skin condition characterized by spine-like papules on the palms and soles. The condition is identified under several names such as "music box spine keratosis" and "palmoplantar filiform hyperkeratosis," creating ambiguity in the diagnostic and histopathologic features of the disease. In this study, we reviewed 84 cases of SpK to examine patient demographics, medical history, clinical and histopathological descriptions, and sporadic versus hereditary onset. Notably, the most used histopathological terms were "parakeratosis" and "hypogranulosis," and the most used clinical terms were "spine" and "hyperpigmented." The average age at presentation was 60.1 years with the majority of cases in males. Only 29.8% of cases were associated with a family history of SpK and underlying malignancies were present in 28.6% of cases. This review investigates the frequency of histopathologic and clinical terms used to describe SpK to provide insight into the clinical and histopathological characteristics of this rarely reported condition.

A possible role for second-hit postzygotic GJB2 mutation in porokeratotic eccrine ostial and dermal duct nevus.

Porokeratotic eccrine ostial and dermal duct nevus (PEODDN) is a rare type of epidermal nevus involving the eccrine acrosyringia. It typically presents as asymptomatic linear keratotic papules and plaques along the lines of Blaschko and predominantly affects the extremities. This disease has recently been linked to somatic mutations within the GJB2 locus. Only four GJB2 mutations have been previously documented for PEODDN, and the underlying genetic basis remains inconclusive. Herein, we report an 18-year-old female with a hyperkeratotic plaque on the dorsa of the proximal interphalangeal joint of her right ring finger, as well as multiple small hyperkeratotic papules linearly distributed on the lateral sides of her fingers occurring since birth. Histopathological results revealed prominent parakeratotic cornoid lamella-like tiers at the opening of the eccrine secretory ducts. Whole-exome sequencing of the affected skin tissue revealed a heterozygous germline mutation and a postzygotic somatic mutation in GJB2. In summary, this study presents a case of PEODDN with compound heterozygous mutations in GJB2, which broadens the genetic spectrum of this disease entity and implies a possible role for second-hit mutations in the pathogenesis of PEODDN.

Hyperkeratotic erythema multiforme variant in 17 dogs.

BACKGROUND: A new canine subgroup defined as 'old-dog' or 'hyperkeratotic' erythema multiforme (HKEM) with marked hyperkeratosis and parakeratosis has been proposed without any detailed description of larger case series. OBJECTIVES: We report herein the signalment, clinical signs, treatment outcome, and histopathological and immunological findings in 17 dogs with HKEM. ANIMALS: Inclusion criteria were the presence of (i) scaly skin lesions with or without crusting; and (ii) microscopic lesions typical of EM (i.e. a panepidermal cytotoxic lymphocytic dermatitis with or without basal keratinocyte apoptosis); and (iii) microscopic ortho- and/or parakeratotic hyperkeratosis affecting the interfollicular epidermis. MATERIALS AND METHODS: Clinical questionnaires and skin biopsies were reviewed. Polymerase chain reactions for epidermotropic viruses and direct immunofluorescence were performed. RESULTS: Various breeds were affected with an over-representation of males in their mid-to-late adulthood (median age 9 years). Generalised skin lesions included multifocal-to-coalescing, linear and annular macules and plaques with erythema and adherent firm crusting. Microscopic lesions were specific for EM and featured prominent superficial epidermal apoptosis with lymphocytic satellitosis and parakeratosis. No drug triggers were identified. Polymerase chain reactions for canine herpesvirus polymerase gene, canine parvovirus and canine distemper virus were negative in all HKEM and canine erosive EM (15 dogs) biopsies. Lesions failed to respond to oral and/or topical antimicrobials. Complete remission of signs was achieved in 9 of 17 dogs (53%) using immunosuppressive regimens. CONCLUSIONS AND CLINICAL RELEVANCE: Hyperkeratotic erythema multiforme (HKEM) is a chronic, persistent and clinically distinctive erythema multiforme (EM) variant that differs from 'classic' vesiculobullous erosive-to-ulcerative EM in dogs.

Erythematous flexural eruption in a young man.

A young man presented with a 2-week history of well-defined erythematous plaques symmetrically distributed in multiple intertriginous areas. He had received topical corticosteroids, antifungals and oral prednisolone without improvement. Histopathological examination revealed confluent parakeratosis with retention of basophilic keratohyalin granules within the stratum corneum. Click here for the corresponding questions to this CME article.

The pits.

A 71-year-old woman presented with a rash in the bilateral axillae. Histopathology showed hyperkeratosis and parakeratosis with retention of basophilic keratohyalin granules.

Dermoscopy of Zosteriform and Swirling Pattern Type 1 Segmental Darier Disease.

Dear Editor, Segmental Darier disease (DD) is a rare disease with around 40 described English literature cases. It is hypothesized that one of the causes of the disease is a post-zygotic somatic mutation for the calcium ATPase pump, only present in lesional skin. There are two types of segmental DD: type 1, where lesions follow Blaschko's lines unilaterally, and type 2, characterized by focal areas of increased severity in patients with generalized DD (1). Type 1 segmental DD is not easily diagnosed due to the lack of positive family history, the late onset of the disease in the third or fourth decade of life, and lack of DD-associated features. The differential diagnosis of type 1 segmental DD includes acquired papular dermatoses distributed in linear or zosteriform fashion, such as lichen planus, psoriasis, lichen striatus, or linear porokeratosis (2). We report two cases of segmental DD, of which the first case was a 43-year-old woman who presented with pruritic skin changes five years in duration and a history of seasonal aggravation. On examination, light brownish to reddish keratotic small papules were observed on the left abdomen and inframammary area, arranged in a swirling pattern (Figure 1, a). Dermoscopy showed polygonal or roundish yellowish/brown areas surrounded with whitish structureless areas (Figure 1, b). The histopathological correlations for dermoscopic brownish polygonal or round areas are hyperkeratosis, parakeratosis, and dyskeratotic keratinocytes, which were present in the biopsy specimen (Figure 1, c). The patient was prescribed 0.1% tretinoin gel, which led to marked improvement (Figure 1, d). The second case was a 62-year-old woman who presented with a flare of small red-brown papules, eroded papules, and some yellowish crusts arranged in a zosteriform pattern on the right side of the upper abdomen (Figure 2, a). Dermoscopy showed polygonal, roundish, yellowish areas surrounded with whitish and reddish structureless areas (Figure 2, b). Histopathology mainly revealed compact orthokeratosis and small foci of parakeratosis, marked granular layer with dyskeratotic keratinocytes, and foci of suprabasal acantholysis consistent with the diagnosis of DD (Figure 2, d, d). The patient was prescribed topical steroid cream and 0.1% adapalene cream, which also led to improvement. In both of our cases, a final diagnosis of type 1 segmental DD was established based on clinico-histopathologic correlation, since acantholytic dyskeratotic epidermal nevus could not have been ruled out only based on the histopathology report as it is clinically and histologically indistinguishable from segmental DD. However, the late age of onset and aggravation resulting from external factors such as heat, sunlight, and sweat supported the diagnosis of segmental DD. Although the final diagnosis of type 1 segmental DD is typically established based on clinico-histopathological correlation, we find dermoscopy particularly useful in aiding the diagnosis by eliminating differential diagnoses and being aware of their well-known dermoscopic patterns.

Histopathologic features of inverse psoriasis.

BACKGROUND: Inverse psoriasis represents a less commonly described form of psoriasis in intertriginous areas. The pathologic findings of inverse psoriasis are typically grouped in with those of plaque psoriasis, as the histopathologic features specific to inverse psoriasis have not received significant investigation. METHODS: A single institution, retrospective cohort study was performed to review biopsy slides for psoriasis occurring in typical intertriginous areas. Patient's charts were reviewed and only those where the clinical diagnosis of inverse psoriasis was also favored were included. RESULTS: Twelve patients met inclusion criteria: 58% male and 42% female, 18 to 86 years of age. Classic features of psoriasis such as hypogranulosis, confluent parakeratosis, and thinning of the suprapapillary plate were seen in 100%. Regular psoriasiform acanthosis and dilated tortuous dermal vessels were seen in 92%. Neutrophils were present in the scale in 83% and in the dermis in 100%. Features considered atypical for psoriasis included spongiosis in 83%, eosinophils in 67%, and focal serum in the scale in 42%. CONCLUSIONS: While inverse psoriasis commonly exhibits features considered to be classic for psoriasis, it is not unusual for inverse psoriasis to show features considered atypical for plaque psoriasis such as dermal eosinophils, epidermal spongiosis, and focal serum in the scale.

Granular parakeratosis secondary to benzalkonium chloride exposure from common household laundry rinse aids.

AIM: Granular parakeratosis (GP) is a benign dermatosis characterised by a rash at intertriginous sites. The pathogenesis is uncertain although it is proposed to be an irritant contact reaction with cases related to benzalkonium chloride (BAC) reported. Our experience is that patients often have delayed diagnosis. This study aims to review the clinical presentation and histopathological features of GP. METHODS: This study is a retrospective case series of adult and paediatric patients seen at dermatology clinics in Auckland, New Zealand. Information was collected on patient demographics, presentation, investigations and management. RESULTS: Thirteen cases (seven adults; six children) are included. The typical presentation of GP was erythematous or brown, scaly papules and plaques with desquamation in a predominantly flexural distribution. All patients reported recent exposure to BAC in laundry rinse solution. Nine biopsies were taken from four patients. Psoriasiform and eczematous findings were common on histopathology. The mainstay of treatment was cessation of BAC exposure. CONCLUSION: GP has a distinct clinical pattern although histopathological findings are varied. Clinicians should have a high index of suspicion for GP in patients presenting with erythematous flexural eruptions and seek a history of BAC exposure, especially in the context of the COVID-19 pandemic and increased antiseptic use.

Mucinous Syringometaplasia: Surrounding Acanthosis With Hyperkeratosis Tends to Conceal the Change.

A 57-year-old man had a 2-year history of a painful nodule on the right sole. Physical examination revealed an 8 × 8 mm hyperkeratotic plaque with a central fissure. Excisional biopsy disclosed epithelial invagination surrounded by the acanthotic epidermis with parakeratotic hyperkeratosis and focal hypergranulosis. The invaginated epithelium lacked a cornified layer and was composed of a mixture of small basaloid squamous cells and goblet cells showing tubular structures. The patient was diagnosed with mucinous syringometaplasia. Our literature review established that surrounding acanthosis with hyperkeratosis typically tends to conceal mucinous syringometaplastic changes. Because mucinous syringometaplasia often presents as an asymptomatic papule/nodule with no distinct ulcer, fissure, or depressed area, cases may be overlooked.

Hiperplasia seudoepiteliomatosa: una reacción infrecuente de los tatuajes / Pseudoepitheliomatous Hyperplasia: An Uncommon Reaction in Tattoos

No disponible

Histopathological changes in epithelium of hair follicles and acrosyringium caused by measles in child.

Some epidermal alterations in measles has been described, such as keratinocytes apoptotic, parakeratosis, giant-cell formation, intranuclear and cytoplasmic inclusions, dyskeratosis, spongiosis, and intracellular edema. The authors report for the first time in human a case of measles with the presence of multinucleated giant cells in the hair follicle and dyskeratosis in acrosyringium.

Abnormal keratinocyte differentiation in the nasal planum of Labrador Retrievers with hereditary nasal parakeratosis (HNPK).

Hereditary nasal parakeratosis (HNPK) is an inherited disorder described in Labrador Retrievers and Greyhounds. It has been associated with breed-specific variants in the SUV39H2 gene encoding a histone 3 methyltransferase involved in epigenetic silencing. Formalin-fixed biopsies of the nasal planum of Labrador Retrievers were screened by immunofluorescence microscopy for the presence and distribution of epidermal proliferation and differentiation markers. Gene expression of these markers was further analysed using RNA sequencing (RNA-seq) and ultrastructural epidermal differences were investigated by electron microscopy. Differentiation of the nasal planum in the basal and suprabasal epidermal layers of HNPK-affected dogs (n = 6) was similar compared to control dogs (n = 6). In the upper epidermal layers, clear modifications were noticed. Loricrin protein was absent in HNPK-affected nasal planum sections in contrast to sections of the same location of control dogs. However, loricrin was present in the epidermis of paw pads and abdominal skin from HNPK dogs and healthy control dogs. The patterns of keratins K1, K10 and K14, were not markedly altered in the nasal planum of HNPK-affected dogs while the expression of the terminal differentiation marker involucrin appeared less regular. Based on RNA-seq, LOR and IVL expression levels were significantly decreased, while KRT1, KRT10 and KRT14 levels were up-regulated (log2fold-changes of 2.67, 3.19 and 1.71, respectively) in HNPK-affected nasal planum (n = 3) compared to control dogs (n = 3). Electron microscopical analysis revealed structural alterations in keratinocytes and stratum corneum, and disrupted keratinocyte adhesions and distended intercellular spaces in lesional samples (n = 3) compared to a sample of a healthy control dog (n = 1). Our findings demonstrate aberrant keratinocyte terminal differentiation of the nasal planum of HNPK-affected Labrador Retrievers and provide insights into biological consequences of this inactive SUV39H2 gene variant.