Classification of Retronychia: A Narrative Clinical Review.

Background: A retronychia classification system is overdue considering the most recent publications. Using the keyword "retronychia", publications with a narrative literature review were selected from PubMed/MEDLINE, EMBASE and Google Scholar, adding a few select papers. Summary: This article proposes a theoretical pathophysiological basis for retronychia. Several factors alter the clinical picture of retronychia: length and periodicity of backward displacement, duration of disease, intensity of paronychia, presence and type of nail stacking (polymeronychia), and remodeling of the nail apparatus (elevation of the proximal nail, nail bed shortening, retroversion of the distal nail fold and acquired malalignment). Key Messages: With these factors in mind, we propose a new classification system for retronychia: A standing for acute, O for ongoing, and C for chronic. We believe this easy system may increase the diagnostic acuity for the disease and its understanding.

Dermoscopic Nail Changes in Psoriasis, Lichen Planus, and Lichen Striatus.

Background: Onychoscopy is a noninvasive method helpful in diagnosing nail disorders. The aim of the study was to review literature on the usability of onychoscopy in nail psoriasis, nail lichen planus, and nail lichen striatus. Summary: Onychoscopic features of nail psoriasis are pitting, onycholysis with erythematous border, salmon patches, splinter hemorrhages, dotted vessels in lateral and proximal folds, and hyponychium. Onychoscopic features of nail lichen planus are onychorrhexis, onycholysis, longitudinal melanonychia, and red lunula. The literature on the usability of onychoscopy in nail lichen striatus is scarce. Keynotes: Onychoscopy facilitates evaluation of nail abnormalities compared to the clinical examination. Lunular alterations, salmon patches, erythematous border of onycholysis as well as splinter hemorrhages in nail psoriasis are better visualized with onychoscopy compared to the naked eye. Onychoscopy enhances detection of melanonychia, dyschromia, and lunular changes in nail lichen planus. Onychoscopic features are different in fingernails and toenails.

Onychoscopy (nail dermoscopy) is a noninvasive method used in diagnosing of nail disorders. In this review, we evaluated if onychoscopy may be helpful in diagnosing inflammatory nail disorders such as psoriasis, lichen planus, and lichen striatus. Nail psoriasis can be characterized with the presence of pitting, salmon patches, splinter hemorrhages, onycholysis with or without erythematous border and dilated vessels in the hyponychium on onychoscopy. Onychoscopy of nail lichen planus shows the presence of longitudinal ridging and splitting (onychorrhexis), splinter hemorrhages, longitudinal melanonychia as well as red lunula (distal part of nail matrix). The data on onychoscopy in nail lichen striatus are scarce. Onychoscopy is a helpful tool in visualization of nail abnormalities, with most of the features better visualized with onychoscopy compared to the naked eye.

Surgery for benign nail tumor.

The vast majority of tumors in the nail apparatus have a different clinical presentation and course from their equivalents on the skin. Some, such as onychomatricoma and onychopapilloma, are unique to the nail and others, such as superficial acral fibromyxoma, have a tropism for the nail apparatus. As a rule, benign lesions respect the general architecture of the nail apparatus, whereas malignant tumors are destructive. Treatment is always surgical and good knowledge of the anatomy and the procedures is mandatory in order not to induce postoperative nail dystrophy.

Update of penetrance estimates in Birt-Hogg-Dubé syndrome.

BACKGROUND: Birt-Hogg-Dubé (BHD) syndrome is a rare genetic syndrome caused by pathogenic or likely pathogenic germline variants in the FLCN gene. Patients with BHD syndrome have an increased risk of fibrofolliculomas, pulmonary cysts, pneumothorax and renal cell carcinoma. There is debate regarding whether colonic polyps should be added to the criteria. Previous risk estimates have mostly been based on small clinical case series. METHODS: A comprehensive review was conducted to identify studies that had recruited families carrying pathogenic or likely pathogenic variants in FLCN. Pedigree data were requested from these studies and pooled. Segregation analysis was used to estimate the cumulative risk of each manifestation for carriers of FLCN pathogenic variants. RESULTS: Our final dataset contained 204 families that were informative for at least one manifestation of BHD (67 families informative for skin manifestations, 63 for lung, 88 for renal carcinoma and 29 for polyps). By age 70 years, male carriers of the FLCN variant have an estimated 19% (95% CI 12% to 31%) risk of renal tumours, 87% (95% CI 80% to 92%) of lung involvement and 87% (95% CI 78% to 93%) of skin lesions, while female carriers had an estimated 21% (95% CI 13% to 32%) risk of renal tumours, 82% (95% CI 73% to 88%) of lung involvement and 78% (95% CI 67% to 85%) of skin lesions. The cumulative risk of colonic polyps by age 70 years old was 21% (95% CI 8% to 45%) for male carriers and 32% (95% CI 16% to 53%) for female carriers. CONCLUSIONS: These updated penetrance estimates, based on a large number of families, are important for the genetic counselling and clinical management of BHD syndrome.

Scleredema diabeticorum.

Scleredema of Buschke is a rare connective tissue disease with a poorly understood pathogenesis. Three types of scleredema have been distinguished according to its association with preceding or underlying conditions. Type 1 is usually secondary to a febrile infection, type 2 is mostly associated with paraproteinemia and type 3, usually named scleredema diabeticorum, has a strict association with Diabetes mellitus. A diffuse, non-pitting swelling and induration of the skin define this disease. The skin histology is characterized by a normal or slightly thinned epidermis, and the dermis containing a decreased number of elastic fibers and thick large swollen collagen bundles separated by mucopolysaccharide deposits in the deep reticular dermis. In this report we present a 58-year-old man with scleredema diabeticorum controlled with a topical steroid cream and an optimization of glycemic control. We reviewed clinical, histopathological characteristics and the various possible treatments.

Dermatitis Cruris Pustulosa et Atrophicans: Scarring Alopecia Beyond Scalp Hair.

Dermatitis Cruris Pustulosa et Atrophicans (DCPA) was first described in 1952 in Nigeria and is nowadays regarded as a type of chronic folliculitis of tropical areas. It is often limited to the lower limbs of young adults, mostly in the second to third decades, with a unique clinical picture characterized by chronicity, relentless progression, therapy refractoriness, and permanent cicatricial changes. Trauma, occlusion, and microorganism selection contribute for its etiopathogenesis, which is deemed multifactorial but still incompletely understood. Despite its conspicuous clinical features, awareness of DCPA is apparently low, hence probably overlooked. We herein summarize the current state of knowledge regarding this distinct entity, and further present the first report in a patient from Bangladesh, and concurrently the first in Europe. Paucity of data, and unraveled definite etiology and treatment, highlight the need for further studies.

Tocilizumab-Induced Erythema Annulare Centrifugum.

We report the case of a 42-year-old woman with rheumatoid arthritis undergoing treatment with subcutaneous tocilizumab for the past 6 months. Three days after the administration, an asymptomatic inflammatory annular plaque of 4 cm with discrete whitish scales at the inner border margin developed at the injection site in the left iliac fossa. A smaller plaque in the left groin appeared soon after. The mycological exam was negative. Histology showed a lymphoplasmacytic superficial and deep perivascular, and periadnexal, dermal infiltrate, without epidermal changes. Lesions spontaneously regressed in 4 months. The diagnosis was clinically and histologically consistent with erythema annulare centrifugum, following the exclusion of other differential diagnoses. Erythema annulare centrifugum represents a delayed-type hypersensitivity reaction generally considered idiopathic or otherwise related to numerous triggers, including drugs such as biologics. We describe the first reported case of tocilizumab-induced erythema annulare centrifugum. This case should alert dermatologists to this relatively rare and complex entity and should raise awareness to cutaneous biologic drug reactions.

Nail Disease: Clinical Decisions among Portuguese Dermatologists and Family Physicians.

Onychomycosis is one of the most common nail disorders and may be difficult to distinguish from other causes of nail dystrophy, based on clinical grounds alone. With this study, we aimed to describe the use of fungal testing by dermatologists and family physicians in their daily current practice, analyze their respective familiarity with nail disease diagnosis, and ultimately treatment decision-making by both groups. An online survey was distributed among Portuguese dermatologists, trainees, and family physicians by email. The survey focused on the diagnostic impression, use of diagnostic methods to confirm a fungal infection, and the subsequent assessment of treatment. One hundred fifty-one responses were obtained, 60 (39.7%) from dermatologists and 91 (60.3%) from family physicians; 98.3% of dermatologists mentioned usually requesting a fungal testing at their local institution or outside, while this percentage was 50.5% among family physicians (p < 0.001). Regarding the diagnosis, the median of correct diagnosis by the dermatologist group was higher (10/15) than the family physicians (6/15). Considering the treatment strategy, we observed that in the dermatologists' group it would result in unnecessary treatment in a median of 2 cases, while in the family physicians' group, in a median of 4 cases.

Fusarium spp.-An Emerging Pathogen in Chronic Diabetic Ulcer: Case Report and Review of the Literature.

The genus Fusarium is ubiquitous in the environment and has been emerging as an opportunistic human pathogen. We report the case of a 65-year-old man with a history of neuroischemic, otherwise unamenable to revascularization, diabetic foot, who was admitted due to an infected deep foot ulcer. Despite conventional antibiotic and wound care treatment, no improvement was initially observed. A reappraisal of the diagnosis, with microbiological and histological analyses, documented infection of the foot ulcer with Fusarium oxysporum. Clinical improvement was noted under prolonged oral voriconazole therapy. The present case broadens the differential diagnosis of diabetic foot infection. Subcutaneous fusariosis should be considered in recalcitrant infected diabetic ulcers, as early diagnosis and management may help prevent amputation and life-threatening disease.

Retronychia: A Paradigm Shift?

Retronychia is an increasingly known cause of paronychia. It was classically regarded as an indication for total nail plate avulsion, but recent case series have questioned the real need for this approach. In order to establish a proper recommendation for patients presenting with retronychia, we retrospectively reviewed all articles with retronychia case reports. Total nail plate avulsion is still the most efficient treatment option. Topical steroids and other noninvasive approaches can be useful in some early, mild cases, but further prospective studies are needed in order to access their efficacy.

Ciclopirox Hydroxypropyl Chitosan (HPCH) Nail Lacquer: A Review of Its Use in Onychomycosis.

Ciclopirox 8% hydroxypropyl chitosan (HPCH) [Marketed in different countries as the following registered (®) brands: Ciclopoli, Fulcare, Kitonail, Myconail, Niogermos, Niogermox, Onytec, Ony-Tec, Polinail, Privex, Rejuvenail] is the first topical nail lacquer developed using innovative drug formulation technology. It is indicated for the treatment of mild-to-moderate fungal infections of the nails that are caused by dermatophytes and/or other ciclopirox-sensitive fungi, without nail matrix involvement. HPCH is a patented drug formulation technology for the delivery of active principles into the nails based on a hydrosoluble semisynthetic amino-polysaccharide biopolymer derivative of chitosan. The lacquer acts as a protective barrier against microbiological attack, physical damage and/or aggressive chemicals. Results from in vitro studies suggest that the application of ciclopirox 8% HPCH nail lacquer improves drug permeation into and/or drug penetration through the nail, relative to the water-insoluble ciclopirox 8%, amorolfine 5% and efinaconazole 10% reference lacquers. In addition, in vitro and clinical studies in healthy subjects found that the concentration of ciclopirox reached in subungual fluids after application of ciclopirox 8% HPCH was sufficient for inhibiting fungal growth. In clinical studies in patients with mild-to-moderate onychomycosis, ciclopirox 8% HPCH was found to be more effective than the commercial water-insoluble ciclopirox 8% and amorolfine 5% lacquers, as indicated by higher complete cure, response and mycological cure rates at 48 weeks after treatment initiation. Ciclopirox 8% HPCH has been found to be generally well tolerated, with no treatment-related adverse events reported in patients using this nail lacquer. Thus, current evidence indicates that ciclopirox 8% HPCH represents a valuable treatment option for the treatment of patients with onychomycosis.

Monotonous Broom Hairs: A Feature of Trichoteiromania.

Trichoteiromania is a self-inflicted traumatic hair injury, with breaking of the hair shafts resulting from repetitive rubbing of the scalp. We describe a patient with trichoteiromania presenting with one lichenified pruriginous plaque on the scalp, associated with fracture and loss of hair shafts giving the conspicuous appearance of monotonous clusters of broom hairs under trichoscopy, which pointed to the diagnosis. As trichoteiromania can be considered a psychodermatological condition, patient education and a behavioral approach are of paramount importance in the management and prognosis of this disorder.

Myxoid Onychomatricoma-A New Case.

Onychomatricoma is a slow-growing, benign neoplasm of the nail matrix with several histological variants. With only 2 cases previously reported, the term "myxoid onychomatricoma" has been used by some authors to describe a rare variant, known to have a fibromixoid component. We present a case of a 51-year-old Caucasian woman with a 1-year history of thickening and discoloration of the right thumbnail, who was initially misdiagnosed as onychomycosis. After performing a magnetic resonance imaging that showed a tumor with several filamentous projections, an onychomatricoma was suspected and a total distal plaque avulsion was performed. Histology revealed a biphasic tumor with an epithelial component and a prominent myxoid stroma. Immunohistochemical staining was then used, confirming the diagnosis. Considering these findings, we believe that our case meets the diagnostic description of "myxoid onychomatricoma" and is, therefore, a new case of this rare histological variant.

Neutrophils in Nail Clipping Histology: A Retrospective Review of 112 Cases.

BACKGROUND: Nail clipping histology is more sensitive than mycology for detecting nail fungi. However, in the absence of fungi, established diagnostic clues for this and other nail dystrophy causes are lacking, namely for nail psoriasis. Neutrophils have been reported in onychomycosis and nail psoriasis samples but have been insufficiently characterized. OBJECTIVES: The aim of this paper is to differentiate neutrophil-containing nail clipping samples in nail psoriasis and onychomycosis regarding histology. METHODS: We performed a 3-year retrospective review of all nail clipping test results included in our department's database and re-analyzed samples containing neutrophils. RESULTS: In total,112 neutrophil-containing nail clipping samples were accounted. Onychomycosis was the commonest diagnosis (74.1%), followed by nail psoriasis (18.8%). Onychomycosis samples had more abundant neutrophils, more often arranged in collections (60.2%) (p = 0.002) and with smaller quantities of parakeratosis, in a lamellar distribution. In nail psoriasis, neutrophils were mostly aggregated (57.1%) with parakeratosis in all samples, in increased amounts, and showing no predominant pattern. CONCLUSIONS: Neutrophils are present in both nail psoriasis and onychomycosis, warranting careful interpretation. However, less dense aggregates of neutrophils with more abundant parakeratosis are clues of nail psoriasis when all other fungal tests are negative.