Finger and toenail onycholysis

Exposome Impact on Nail Health

Background

The nail unit is a complex system with various components, each serving distinct functions. The exposome, encompassing external and internal factors such as UV radiation, air pollution, dietary habits, and cosmetic product usage, substantially influences nail health and can lead to premature nail aging.

Summary

Internal and external exposomal factors can impact differently on nail health, inducing a variety of different clinical conditions. Effective therapeutic strategies exist, but a comprehensive understanding of how the exposome affects nails is lacking. This article aims to bridge this knowledge gap by exploring the relationship between the exposome and nail health, emphasizing it as a central focus of our analysis.

Key Messages

(1) The exposome, comprising various external and internal factors, may significantly influence nail health negatively, leading to premature nail aging. (2) Different nail conditions may arise due to the exposomal influence on nails. (3) Understanding the exposome's impact on nail health is crucial for developing solutions to mitigate negative effects and improve overall nail well-being.

Candida albicans skin infection in diabetic patients: An updated review of pathogenesis and management

Candida species, commensal residents of human skin, are recognized as the cause of cutaneous candidiasis across various body surfaces. Individuals with weakened immune systems, particularly those with immunosuppressive conditions, are significantly more susceptible to this infection. Diabetes mellitus, a major metabolic disorder, has emerged as a critical factor inducing immunosuppression, thereby facilitating Candida colonization and subsequent skin infections. This comprehensive review examines the prevalence of different types of Candida albicans-induced cutaneous candidiasis in diabetic patients. It explores the underlying mechanisms of pathogenicity and offers insights into recommended preventive measures and treatment strategies. Diabetes notably increases vulnerability to oral and oesophageal candidiasis. Additionally, it can precipitate vulvovaginal candidiasis in females, Candida balanitis in males, and diaper candidiasis in young children with diabetes. Diabetic individuals may also experience candidal infections on their nails, hands and feet. Notably, diabetes appears to be a risk factor for intertrigo syndrome in obese individuals and periodontal disorders in denture wearers. In conclusion, the intricate relationship between diabetes and cutaneous candidiasis necessitates a comprehensive understanding to strategize effective management planning. Further investigation and interdisciplinary collaborative efforts are crucial to address this multifaceted challenge and uncover novel approaches for the treatment, management and prevention of both health conditions, including the development of safer and more effective antifungal agents.

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.

Cross-sectional study of the prevalence of hyperextension of the first metatarsophalangeal joint and its relationship to onycholysis in women with hallux valgus

BACKGROUND

Hallux Valgus (HV) deformity is associated with misalignment in the sagittal plane that affects the first toe. However, the repercussions of the first toe hyperextension in HV have been scarcely considered. The purpose of this study was to provide evidence of the association between first-toe hyperextension and the risk of first toenail onycholysis in HV.

METHODS

A total of 248 HV from 129 females were included. The extension of 1st MTP joint was measured while the patient was in the neutral position of the hallux using a two-branch goniometer. The classification of the HV severity stage was determined by the Manchester visual scale, and the height of the first toe in the standing position was measured using a digital meter. An interview and clinical examination were performed to collect information on the presence of onycholysis of the first toe.

RESULTS

Of the 248 HV studied, 100 (40.3%) had onycholysis. A neutral extension > 30 degrees was noted in 110 (44.3%) HV. The incidence of onycholysis was higher in HV type C than in type B (p = 0.044). The probability of suffering onycholysis in the right foot was 2.3 times greater when the neutral position was higher than 30 degrees (OR = 2.3; p = 0.004). However, this was not observed in the left foot (p = 0.171). Onycholysis was more frequent in HV with more than 2 cm height of the first toe (p < 0.001). For both feet, the probability of suffering onycholysis was greater for each unit increase in hallux height (right foot OR = 9.0402, p = 0.005; left foot OR = 7.6633, p = 0.010).

CONCLUSIONS

The incidence of onycholysis appears to be significantly associated with HV showing more than 30º extension, and more than 2 cm height of the first toe. Height and hyperextension of the first toe together with first toenail pathology should be mandatory in the evaluation of HV.

Frontal Examination of the Distal Nail Unit

Clinical findings in many nail disorders are not usually pathognomonic. An accurate diagnosis therefore relies on inspection of the nail unit from different angles. We review clinical features of different nail disorders that can be observed during frontal examination of the distal edge of the nail plate and the hyponychium and correlate these with features observed when the nail is viewed from above. Frontal examination of the distal nail unit can help establish a clinical diagnosis in routine practice.

[Translated article] Frontal Examination of the Distal Nail Unit

Clinical findings in many nail disorders are not usually pathognomonic. An accurate diagnosis therefore relies on inspection of the nail unit from different angles. We review clinical features of different nail disorders that can be observed during frontal examination of the distal edge of the nail plate and the hyponychium and correlate these with features observed when the nail is viewed from above. Frontal examination of the distal nail unit can help establish a clinical diagnosis in routine practice.

Dermoscopy of Onychomycosis: A Systematic Review

INTRODUCTION

Onychomycosis represents a global burden accounting for about 50% of nail consultations. Several studies have tried to assess the dermoscopic features of onychomycosis. With the multiplication of papers, several "new" dermoscopic signs keep being added leading to some inconsistency in onychoscopic terminology.

OBJECTIVE

This study aimed to summarize the existing literature on the dermoscopic features of onychomycosis and propose a unified onychoscopic terminology.

METHODS

The literature search was performed using PubMed and Scopus databases up to October 30, 2021 to identify eligible contributions. In total, 33 records (2111 patients) were included.

RESULTS

The main dermoscopic signs of onychomycosis are "ruin appearance", "longitudinal striae" and "spikes" on the proximal margin of onycholytic areas, with a specificity of 99.38%, 83.78%, and 85.64% respectively. The "aurora borealis" sign had the highest sensitivity and specificity.

CONCLUSIONS

The current review provides a framework for issues related to the onychoscopic terminology of onychomycosis and is intended to serve as an aid for students, teachers, and researchers. We proposed a unifying terminology to describe dermoscopic signs of onychomycosis. Dermoscopic signs of onychomycosis show good specificity and are useful in distinguishing nail psoriasis, trauma, and onychomycosis. It helps differentiate fungal melanonychia from nail melanoma, nevi, and melanocytic activation.

Recognizing skin conditions in patients with cirrhosis: a narrative review

Background: The skin is a major target organ for extrahepatic manifestations of liver diseases, and dermatologic abnormalities are common in patients with hepatic disorders. Clinical examination of the skin, nails and hair can allow for appropriate recognition, early diagnosis and treatment of liver diseases, and improvement in the quality of life and life expectancy of affected patients.Methods: We searched 3 databases (Pubmed,Medline and Embase) and selected studies about cirrhosis related skin manifestations and their pathophysiology.Results: A total of 73 articles were included in the review. Studies displayed the spectrum of cutaneous manifestations related to hormonal and vascular changes as well as nail and hair changes in patients with cirrhosis and/or portal hypertension.Conclusion: Cutaneous alterations are important clues or potential indications in the diagnosis of liver cirrhosis. Familiarity with skin conditions can be promptly diagnosed and appropriate management initiated.KEY MESSAGESManifestations of the liver and skin disorders are interrelated in various ways. Cutaneous changes may be the first clue that a patient has liver disease.The skin is a major target organ for extrahepatic manifestations of liver diseases. A broad range of cutaneous alterations can be present in patients with cirrhosis, such as vascular, nail, hair, hormonal changes, etc.Recognizing these signs is crucial so that potential underlying diseases including liver disease can be promptly diagnosed and appropriate management timely initiated.

Disappearing Nail Bed: Review of Etiology, Grading System, and Treatment Options

Disappearing nail bed (DNB) is a condition characterized by irreversible epithelialization of the nail bed following long-standing onycholysis. This phenomenon can occur in fingernails and toenails. Factors implicated in the development of DNB include trauma, manicuring, and onychotillomania and dermatologic conditions like psoriasis and dermatitis. Specifically for the toenail, contributing factors also include increasing age, history of trauma, surgery, onychomycosis, and onychogryphosis. A grading system that stages the progression of onycholysis to DNB has been proposed to aid clinicians in the diagnosis and treatment of these conditions. Several methods have been designated for the treatment of DNB.

Challenge of Nail Psoriasis: An Update Review

Nail psoriasis is a refractory disease that affects 50-79% skin psoriasis patients and up to 80% of patients with psoriatic arthritis (PsA). The pathogenesis of nail psoriasis is still not fully illuminated, although some peculiar inflammatory cytokines and chemokines seems to be the same as described in psoriatic skin lesions. Psoriatic nail involving matrix can cause pitting, leukonychia, red spots in lunula, and nail plate crumbling, while nail bed involvement can result in onycholysis, oil-drop discoloration, nail bed hyperkeratosis, and splinter hemorrhages. The common assessment methods of evaluating nail psoriasis includes Nail Psoriasis Severity Index (NAPSI), Nail Assessment in Psoriasis and Psoriatic Arthritis (NAPPA), Nail Psoriasis Quality of life 10 (NPQ10), and so on. Treatment of nail psoriasis should be individualized according to the number of involving nail, the affected site of nail and presence of skin and/or joint involvement. Generally, topical therapies are used for mild nail psoriasis, while biologic agents such as etanercept are considered for severe nail disease and refractory nail psoriasis. Even though the current literature has shown some support for the pathogenesis, clinical presentation, or therapies of nail psoriasis, systemic review of this multifaceted disease is still rare to date. We elaborate recent developments in nail psoriasis epidemiology, pathogenesis, anatomy, clinical manifestation, diagnosis, differential diagnosis, and therapies to raise better awareness of the complexity of nail psoriasis and the need for early diagnosis or intervention.

Chemical Gastroenterocolitis after Dental Root Canal Therapy with Camphorated and Mentholated Chlorophenol

A 78-year-old man with a history of pancolitis, after the treatment of dental abscess with oral antibiotics and local application of camphorated and mentholated chlorophenol (CMCP), presented with abdominal pain of 4-day duration, as well as hair loss in the area of moustache and finger nail lifting. He was already treated with rectal application of budesonide because of pancolitis, diagnosed 6 weeks ago and interpreted as an allergic reaction to clindamycin. For further investigation, we performed gastroscopy and colonoscopy, which showed the edematous mucosa with polypus-like changes of the whole mucosa of the stomach, duodenum, first part of the jejunum, distal ileum, complete colon, and rectum. The diagnosis was complicated and was achieved in synopsis with anamnestic details, such as endodontic application of camphorated chlorophenol. The patient symptoms abated after he commenced on mesalazine therapy.

Diagnosis of Onychomycosis: From Conventional Techniques and Dermoscopy to Artificial Intelligence

Onychomycosis is a common fungal nail infection. Accurate diagnosis is critical as onychomycosis is transmissible between humans and impacts patients' quality of life. Combining clinical examination with mycological testing ensures accurate diagnosis. Conventional diagnostic techniques, including potassium hydroxide testing, fungal culture and histopathology of nail clippings, detect fungal species within nails. New diagnostic tools have been developed recently which either improve detection of onychomycosis clinically, including dermoscopy, reflectance confocal microscopy and artificial intelligence, or mycologically, such as molecular assays. Dermoscopy is cost-effective and non-invasive, allowing clinicians to discern microscopic features of onychomycosis and fungal melanonychia. Reflectance confocal microscopy enables clinicians to observe bright filamentous septate hyphae at near histologic resolution by the bedside. Artificial intelligence may prompt patients to seek further assessment for nails that are suspicious for onychomycosis. This review evaluates the current landscape of diagnostic techniques for onychomycosis.

Methyl Ethyl Ketone-Related Loss of Matrix With Nail Onycholysis and Pterygium (ME KLMNOP): Case Report of a New Etiology for Onycholysis and Pterygium

Methyl ethyl ketone is an organic solvent commonly used in adhesives and paints. Overexposure to methyl ethyl ketone can irritate the central nervous system, eyes, and respiratory system. When in direct contact with skin, methyl ethyl ketone can lead to dryness and cracking of the skin. Forty years ago, methyl ethyl ketone was used in the Navy to degrease and remove paint from planes and naval equipment. A 57-year-old Navy veteran presented with an absence of all fingernails and thumbnails as well as pterygium formation on his digits; however, his toenails were normal. Additional history revealed that his unprotected hands were regularly exposed to methyl ethyl ketone for three years. His nails shed and stopped growing after one year of this work; subsequently, pterygiums developed. We postulate that exposure to methyl ethyl ketone may result in chemical destruction of the nail matrix in a similar manner to phenol or sodium hydroxide. We introduce the following acronym that describes not only the etiology but also the manifestations of Methyl Ethyl Ketone-related Loss of Matrix with Nail Onycholysis and Pterygium (ME KLMNOP).

Clinical significance of Candida isolation from dystrophic fingernails

BACKGROUND

Candida onychomycosis mostly involves fingernails. Yet, in contrast to dermatophytes, Candida isolation from dystrophic fingernails does not prove casualty, as sample contamination and non-pathogenic Candida growth occur. Characterising treatment outcome of Candida-positive dystrophic nails is crucial to avoid unnecessary treatment.

OBJECTIVE

To investigate predicators associated with treatment outcome among Candida-positive dystrophic fingernails.

PATIENTS AND METHODS

A retrospective cohort study was carried out among 108 adults with Candida-positive dystrophic fingernails not cured with adequate systemic anti-fungal course. Diagnosis was based on a single mycological culture. Patients with treatment failure (n = 85; 78.7% of the cases) were compared to patients with partial response (mild to almost cure; n = 23; 21.3% of the cases) at 9 to 12 months following treatment initiation.

RESULTS

Treatment failure was significantly associated with primary onycholysis (odds ratio [OR] 2.8; 95% confidence interval [CI] 1.1-7.4) and prolonged dystrophy (12.8 vs. 3.7 years in average), compared to partial treatment response. Non-responders had lower odds to present with distal lateral subungual onychomycosis, compared to partial responders (OR 0.3; 95% CI 0.1-0.7). Demographic and mycological characteristics, as well as number of nails affected, co-presence of paronychia, and treatment regime were not found to be associated with treatment response.

CONCLUSION

Candida-positive primary onycholysis was shown to be non-responsive to systemic anti-fungal treatment, suggesting that anti-fungal treatment is not indicated. For other clinical scenarios, high proportions of treatment non-response suggest that determining causality of Candida should not be based on a single positive mycological culture.

Retrospective Case Series on Risk Factors, Diagnosis and Treatment of Pseudomonas aeruginosa Nail Infections

BACKGROUND

Pseudomonas aeruginosa is the most common pathogen causing bacterial nail infections, producing a classic blue-green pigment, known as chloronychia. Clinical examination and dermoscopic findings, as well as diagnosis and treatment, have not been well characterized.

OBJECTIVE

The aim was to characterize the clinical and dermoscopic findings of P. aeruginosa infection of the nails and assess treatment efficacy.

METHODS

This is a retrospective study of patients with P. aeruginosa nail infection diagnosed between January 27, 2017 and May 28, 2019. Demographics, history, clinical and dermoscopic findings, diagnostics tests, and treatment were documented and analyzed.

RESULTS

Twenty-six patients with P. aeruginosa nail infections were analyzed, with 21 patients completing treatment, two lost to follow-up, and three still undergoing treatment. Clinical examination findings were notable for onycholysis in 76.9% of patients. Green discoloration was seen in 38.5% of patients and green-brown discoloration in 30.8%. A majority of the patients had only one nail involved (73.1%). Dermoscopic findings were significant for greenish pigmentation in 37.5% of patients and 88.9% of cases presenting with a fading border. Wound cultures of nail plates were more sensitive (40%) than dermatopathology (16.7%), but the difference was not statistically significant (p value = 0.1596). All patients were treated with ophthalmic 0.3% gentamicin topical solution nightly for a 3-month period and those who completed therapy had complete resolution of their infection.

LIMITATIONS

The limitations of the study were the retrospective design and the small cohort size.

CONCLUSION

Clinical examination findings of onycholysis coupled with a green or green-brown discoloration involving one or more digits and dermoscopic findings of greenish discoloration with a fading border are consistent with a diagnosis of Pseudomonas nail infection. Gentamicin topical solution is an effective, inexpensive, easy-to-use treatment for this condition. Larger randomized clinical trials are necessary to compare efficacy with other therapeutic options.

Biomechanical Factors in Psoriatic Disease: Defective Repair Exertion as a Potential Cause. Hypothesis Presentation and Literature Review

Joining main clinical manifestations of psoriatic skin disorder are inflammatory arthritis and nail lesions. Repetitive microdamage has been postulated as a main triggering factor in lesions of psoriatic arthritis. This concept of psoriatic disease might also be admissible for triggering nail lesions because the nail is a frequently traumatized structure. Here, we aimed to describe the conjectural injury mechanisms of nail complex with regard to acting biomechanical factors. Tissue repair response to physical microdamage may be altered in psoriatic disease. It is plausible to consider that a defective repair process in the dysregulated prepsoriatic tissue may lead to innate immune activation and further development of autoinflammatory lesions, although excessive inflammation is known to impair wound healing. Recently published data have revealed the importance of mechanosensitive Wingless-type (Wnt) signaling in the pathophysiology of psoriasis and ankylosing spondylitis. The Wnt signaling system is involved in morphogenesis, repair, and regeneration as a biologic process main regulator. Wnt5a seems to be a dominating mediator in both psoriatic plaques and during the spondylitis process that might also be a linking molecule of psoriatic response to mechanical stress. Future studies should focus on complex responsive interactions of tissue repair regulators regarded in psoriatic disease.

New insight into the pathogenesis of nail psoriasis and overview of treatment strategies

Psoriasis is a chronic inflammatory disease affecting up to 3% of the general population. The prevalence of nail involvement in psoriasis patients varies between 15% and 79%. While the nails represent a small portion of the body surface area, psoriasis in these areas can have a disproportionate influence on a patient’s physical and psychosocial activities. Differential diagnosis between an onychomycosis and a psoriatic nail could be challenging; nevertheless, coexistence of onychomycosis and nail psoriasis also occurs and both are common disorders in the general population. Nail psoriasis can be difficult to treat. Treatment of nail psoriasis should consider the body surface area of skin disease, psoriatic arthritis, severity of nail disease, and the impairment in the quality of life. All patients should be tested for onychomycosis before starting a therapy. This recommendation is underlined by the fact that nail psoriasis is mostly treated by immunosuppressive drugs, like steroids, methotrexate, or biologics, which may aggravate mycotic nail infections. Conventional systemic therapy, such as use of steroids, cyclosporine, methotrexate, and retinoid in the long term, can cause organ toxicities. Currently, use of apremilast and tofacitinib favors an early healing of nail psoriasis because they act directly on the pathogenic targets, distressing the inflammatory signals associated with the initiation and maintenance of the disease activity, and as with several conventional synthetic disease modifying antirheumatic drugs, they are characterized by the convenience of oral administration. The number of treatment options has increased considerably in recent years; however, given the heterogeneity of the disease, the therapy should be personalized to individual cases.

A Clinician's Guide to the Diagnosis and Treatment of Candidiasis in Patients with Psoriasis

Many of the molecular pathways associated with psoriasis pathogenesis are also involved in host defense mechanisms that protect against common pathogens. Candida can stimulate the production of cytokines that trigger or exacerbate psoriasis, and many systemic psoriasis treatments may put patients at increased risk for developing oral, cutaneous, and genitourinary candidiasis. Therefore, dermatologists should regularly screen patients with psoriasis for signs of Candida infection, and take steps to effectively treat these infections to prevent worsening of psoriasis symptoms. This review provides an overview of candidiasis epidemiology in patients with psoriasis, followed by a primer on the diagnosis and treatment of superficial Candida infections, with specific guidance for patients with psoriasis. Candidiasis in patients with psoriasis typically responds to topical or oral antifungal therapy. While biologic agents used to treat moderate-to-severe psoriasis, such as tumor necrosis factor-α inhibitors and interleukin-17 inhibitors, are known to increase patients’ risk of developing localized candidiasis, the overall risk of infection is low, and candidiasis can be effectively managed in most patients while receiving systemic psoriasis therapies. Thus, the development of candidiasis does not usually necessitate changes to psoriasis treatment regimens.