Green nail: Etiology and treatment of chloronychia.

"Green nails" or chloronychia results from an infection mostly caused by Pseudomonas sp. but also from other bacterial or fungal contamination. Its presents as a typical triad: green discoloration of the nail plate with proximal chronic paronychia and disto-lateral onycholysis. In a moist environment, Pseudomonas colonizes onycholysis of any origin (traumatic, inflammatory or tumoral). Nail color varies from pale green to dark green, almost black. Treatment consists in cutting of the detached nail plate, brushing the nail bed with a 2% sodium hypochlorite solution twice daily accompanied by moisture eviction by wearing latex gloves over cotton ones for all daily household tasks.

Onychomatricomas: A 41-Case Series to Assess Surgical Outcome.

BACKGROUND: Onychomatricoma (OM) is a rare benign tumor of the nail matrix. Treatment is surgical, but data are currently limited. OBJECTIVE: To review all cases of OM operated in their department and to assess the link between the location on the nail plate, the thickness and width of the lesion, and the postoperative outcomes. MATERIALS AND METHODS: Records of 62 patients were retrieved from their department's database over a 25-year period (1998-2023). RESULTS: Of the 62 patients, 41 were eligible. In total, 58% of OM occupied a width of a quarter of the nail plate, 51% had a plate thinner than 3 mm, and 51% were laterally located. Of the 41 patients included, 29 had a tangential excision and 12 underwent lateral longitudinal excision. Among the tangential excision group, 71% had normal nail regrowth. Onychomatricoma thicker than 3 mm and involving the total nail plate width had a sequelae in 60% of cases. CONCLUSION: Tangential excision of onychomatricomas allows a normal nail regrowth in 71% of cases. The risk of sequelae increases for tumors thicker than 3 mm and involving the total nail plate width. Medial or lateral location seems to have no influence.

Nail cosmetology.

Nail cosmetics is enjoying growing success due to recent technological advances. Manicures can be responsible for mechanical, infectious or allergic adverse effects. Nail cosmetics (e.g., nail varnishes, acrylic false nails, light-curing gels, and adhesive false nails) incorporate substances that harden after solvent evaporation or after polymerization. Allergic reactions can occur, remotely with conventional varnishes and locally with polymerizing substances. Artificial nails incur a risk of carrying infectious agents which can cause serious infection, and should not be used by caregivers. Recently, there has been a worrisome increase in the frequency of acrylate allergy, due to the appearance of home kits and lack of information in the general public. The infectious, allergic and toxic risks incurred by consumers and professionals regarding manicure or pedicure treatments and the application of nail cosmetics are the subject of recommendations and monitoring measures.

Onychomycosis.

Onychomycosis is a fungal infection of the nail, and the most common nail infection worldwide, causing discoloration and thickening of the nail plate. It is predominantly caused by dermatophytes. Clinical presentation is polymorphous. Diagnosis must be confirmed by mycological examination before initiating any therapy. Management is an ongoing challenge, often requiring several months' treatment, with a high risk of recurrence. Treatment must be adapted to clinical presentation and severity and to the patient's history and wishes. Debridement of all infected keratin is the first step, reducing fungal load. Systemic treatments are more effective than topical treatments, and combining the two increases the cure rate. Terbinafine is the drug of choice for dermatophyte onychomycosis, due to low drug interaction and good cost-effectiveness. Itraconazole and fluconazole are broad-spectrum antifungals that are effective against dermatophytes, yeasts, and some non-dermatophytic molds. Recurrence rates for onychomycosis are high. Prophylactic application of topicals and avoiding walking barefoot in public places may help prevent recurence.

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.

Nail disorders to be kept in mind.

Recognizing and diagnosing the most common nail diseases is essential, to be able to guide patients and provide appropriate treatment. However, uncommon nail disorders should not be neglected, in order to avoid inadequate treatment and above all to ensure that no severe underlying disorder, with severe prognosis, is overlooked.

Examination of the nails: Main signs.

Understanding the anatomy of the nail apparatus is a prerequisite for diagnosing and managing various nail disorders. The latter may be associated with systemic pathologies, or accompany infectious, inflammatory, tumoral, toxic or traumatic dermatoses. Before attempting to identify the cause, a rigorous clinical examination should be conducted to screen for elementary lesions that may affect general nail shape, nail surface, subungual attachments, periungual soft tissue or nail color. All of these guide differential diagnosis.

Three atypical/malignant onychopapillomas in a 52-case series with immunohistochemical study.

BACKGROUND: Onychopapilloma (OP) is a benign tumor of the nail. Haneke reported one case of malignant OP in 2021. No systematic immunohistochemistry study has been conducted on OP. The aim of our study was to identify possible malignant OP in our series of OP and to describe the immunohistochemical expression of p16, p53, and Ki67 in typical and atypical/malignant ones. METHODS: Ninety-one cases were available for pathological review. Immunohistochemical analysis could be performed on 52 cases. RESULTS: In 88 of 91 cases, the diagnosis of OP was confirmed. Three atypical/malignant cases were observed. No OP expressed p16. A normal p53 expression was observed in two thirds of the cases, an abnormal increased p53 expression in one third, including the three atypical cases. A normal Ki67 expression was observed in 84% of the cases, an abnormal Ki67 expression with focal heterogeneous expression in the suprabasal layers in 6% and in all suprabasal cell layers in 10%, including the three atypical cases. CONCLUSIONS: The diagnosis of atypical/malignant OP may be underestimated. The expression of Ki67 and p53 in these tumors differs from the expression observed in conventional OP. The absence of p16 expression confirms that human papillomavirus does not play a role in the etiopathogenesis of OP.

Management of ingrowing nail.

For decades, there has been debate about the cause of ingrown nail: is the nail plate or the periungual tissue at fault? There is no consensus and management relies on case-by-case analysis followed by tailored treatment. Conservative treatment should be attempted in children when the cause is transient (e.g., poor clipping) or the patient refuses surgery. Surgical treatments rely on two main approaches: either narrowing the nail plate, or debulking the soft tissue. It is up to the surgeon to select the most appropriate approach in each case. All procedures discussed in this chapter have high cure rates as long as they are properly performed. As with all surgical procedures, they are operator-dependent. Chemical cautery is the easiest and most versatile technique that may help in almost all instances for lateral ingrowth. For distal ingrowth and very hypertrophic and exuberant lateral folds, debulking with primary or secondary healing is most effective.

Kaposi Sarcoma of the Nail Unit: A Case Report and Review of the Literature.

Introduction: Kaposi sarcoma is an angioproliferative neoplasm. Its manifestations are well known but nail involvement seems extremely underreported. Case Presentation: A 55-year-old man presented with a 6-month history of a growing subungual tumor affecting the third right toe. After surgical excision, histological examination revealed a Kaposi sarcoma. Discussion: We report a case of Kaposi sarcoma with nail involvement of only one toe as the first and unique manifestation, which is exceptional.

Nail Amyloidoma: Two Case Reports of a New Entity.

Introduction: Amyloidosis is a group of diseases characterized by extracellular deposits of abnormal insoluble proteins in different tissues. Amyloidoma is a localized tumoral deposit of amyloid in the absence of systemic amyloidosis, and it has been described in different anatomic sites. We report two cases of amyloidoma in the nail unit and provide insights into this recently described entity. Case Presentation: Both cases presented as an asymptomatic, slowly growing nodule underneath the distal nail bed of a toe with associated onycholysis. Histopathology was characterized in both patients by the presence of deposits of Congo red-positive, homogeneous, amorphous, and eosinophilic material within the dermis and subcutaneous tissue admixed with aggregates of plasma cells. In both cases, an extensive workup excluded systemic amyloidosis. Treatment was based on local excision, and no local recurrence or progression to systemic amyloidosis was observed at 1 year of follow-up. Conclusion: These are the first reports of amyloidomas of the nail unit. The clinical and histopathological presentations parallel those of an amyloidoma affecting the skin. Local excision seems to be an efficient treatment modality, but long-term follow-up is warranted in order to exclude recurrence, an associated marginal B-cell lymphoma, or progression to systemic amyloid L amyloidosis.

A clinicopathological description of COVID-19-induced chilblains (COVID-toes) correlated with a published literature review.

BACKGROUND: The abundance of publications of COVID-19-induced chilblains has resulted in a confusing situation. METHODS: This is a prospective single-institution study from 15 March to 13 May 2020. Thirty-two patients received PCR nasopharyngeal swabs. Of these, 28 patients had a thoracic CT-scan, 31 patients had blood and urine examinations, 24 patients had skin biopsies including immunohistochemical and direct immunofluorescence studies, and four patients had electron microscopy. RESULTS: COVID-19-induced chilblains are clinically and histopathologically identical to chilblains from other causes. Although intravascular thrombi are sometimes observed, no patient had a systemic coagulopathy or severe clinical course. The exhaustive clinical, radiological, and laboratory work-up in this study ruled-out other primary and secondary causes. Electron microscopy revealed rare, probable viral particles whose core and spikes measured from 120 to 133 nm within endothelium and eccrine glands in two cases. CONCLUSION: This study provides further clinicopathologic evidence of COVID-19-related chilblains. Negative PCR and antibody tests do not rule-out infection. Chilblains represent a good prognosis, occurring later in the disease course. No systemic coagulopathy was identified in any patient. Patients presenting with acral lesions should be isolated, and chilblains should be distinguished from thrombotic lesions (livedo racemosa, retiform purpura, or ischemic acral necrosis).

Nail surgery: the effect of clinical and psychological characteristics on post-surgical quality of life and pain severity

Background: Nail disease and nail surgery are commonly perceived as painful and distressful experiences that can significantly affect patient health-related quality of life. A comprehensive management of patients undergoing dermatological surgery could improve their emotional experience, influence quality of life and, hopefully, improve their adaptation to the intervention. Objectives: This study aimed to investigate whether patient psychological characteristics may relate to nail intervention procedures and influence post-surgical quality of life and pain severity. Materials & Methods: This prospective observational monocentric cohort study was conducted in the Dermatology Nail Unit of Bologna. Patient candidates for nail surgery, meeting the inclusion criteria, were invited to participate in the study which consisted of completion of a self-report questionnaire before (Time 1) and one month after (Time 2) surgery. Results: Nail surgery was performed for 102 patients: 46 underwent highly invasive and 56 mildly invasive nail procedures. In total, 46 nail tumours were excised which were shown to be benign in 36 cases and malignant in 10 cases. Patients with a high level of pain sensitivity and trait of anxiety reported significantly lower levels of quality of life and high levels of pain intensity one month after surgery (p < 0.001). Conclusion: Our findings highlight the need for clinicians to consider the psychological characteristics of patients following dermatological surgery care in order to balance the negative impact of trait anxiety, pain sensitivity and negative treatment expectations regarding post-surgery quality of life and pain severity.

Distal phalangeal bone erosions observed by HR-pQCT in patients with psoriatic onycholysis.

OBJECTIVES: PsA prevalence among skin psoriasis is ∼30%. Nail psoriasis, especially onycholysis, is present in >70% of PsA and the risk of developing PsA is more than doubled in patients with nail involvement. We hypothesized that onycholysis may be associated with early bone erosions of the DIP joint without harbouring PsA symptoms. METHODS: We compared tendon thickness, assessed by US, and bone erosions, assessed by high-resolution peripheral quantitative CT, of the DIP joint in patients with psoriatic onycholysis without PsA (ONY) with those in patients with cutaneous psoriasis only (PSO). We used patients with PsA as reference (PsA group), and healthy age-matched controls (CTRL). Differences between groups were assessed by analysis of variance tests followed by post hoc analysis using the Scheffe method. RESULTS: Mean (s.e.m.) age of the 87 participants (61% males) was 45.2 (1.3) years. The mean extensor tendon thickness was significantly larger in ONY than in PSO patients. In the PsA group, 68% of patients exhibited erosions of three different shapes: V-, Omega- and U-shape. Association with erosions was greater in the ONY group than in the PSO group (frequency: 57 vs 14%; P < 0.001; mean number of erosions: 1.10 (0.35) vs 0.03 (0.03); P < 0.001). CONCLUSION: Onycholysis was associated with significant enthesopathy and bone erosions in our cohort. These data support the pathogenic role of enthesopathy in PsA. Onycholysis may be considered as a surrogate marker of severity in psoriasis. TRIAL REGISTRATION: ClinicalTrails.gov, https://clinicaltrials.gov, NCT02813720.

Nail Unit Blue Nevi: A 11-Case Series and Review of the Literature.

BACKGROUND: Blue nevus of the nail apparatus is a rare entity and only isolated cases are reported in the literature. OBJECTIVE: The aim of this study was to better characterize blue nevus at the nail unit. METHODS: Retrospective analysis of all nail unit blue nevi from the Nail Group of the French Society of Dermatology was compared to the literature. RESULTS: Eleven cases were retrieved from 2002 to 2019 with an average age of 45 years. The majority were women (9/11) and acquired (10/11). Hands were more frequently involved (9/11) with a predilection for the thumb and 2 cases were located on the hallux. Nail unit blue nevus mostly presented as a well-delimited blue spot of the lunula (9/11) and histologically was of the common type (10/11). There was no malignancy. CONCLUSION: Nail unit blue nevus is a rare asymptomatic benign entity, mostly acquired on the thumb or the hallux of women. The most frequent presentation is a painless blue spot on the lunula. Congenital blue nevi seem to only affect the paronychium. Main differential diagnosis is melanoma and histopathological examination is mandatory.