Comparison of dermoscopic characteristics on toenail onychomycosis in psoriatic and non-psoriatic patients: A prospective study

BACKGROUND

Psoriatic patients may experience the coexistence of onychomycosis (OM). However, the evaluation of OM in psoriatics has been hindered by potential clinical differences from OM in non-psoriatics.

OBJECTIVE

To assess and compare dermoscopic features between toenail OM in psoriatic and in non-psoriatic patients.

PATIENTS AND METHODS

Between September 2020 and September 2023, dermoscopy was conducted on 183 affected toenails by OM in psoriatics and 232 affected toenails by OM in non-psoriatics in two centres. The dermoscopic characteristics were compared using the Chi-squared test.

RESULTS

Among toenail OM cases in psoriatic subjects, the most prevalent dermoscopic features included pitting (147/183, 80.33%) and subungual hyperkeratosis (118/183, 64.48%). Conversely, toenail OM in non-psoriatics was characterized by subungual hyperkeratosis (175/232, 75.43%) and nail spikes (139/232, 59.91%). Comparative analysis revealed a significantly higher occurrence of pitting (80.33% vs. 15.96%, p < .001), periungual telangiectasis (22.40% vs. 4.74%, p < .001), oil patches (12.57% vs. 0.43%,p < .001) and transverse grooves (43.72% vs. 28.45%,p < .01) in toenail OM in psoriatics. Furthermore, toenail OM in psoriatics exhibited a significantly lower frequency of yellow structureless area (13.11% vs. 42.67%, p < .001), nail spikes (43.17% vs. 59.91%, p < .01), ruin appearance of sulphur nugget (8.20% vs. 31.03%, p < .001), dotted/blocky haemorrhage (6.01% vs. 20.69%,p < .001) and partial onycholysis (32.79% vs. 46.98%, p < .01).

CONCLUSIONS

Dermoscopic features of toenail OM in psoriatic and non-psoriatic patients exhibit notable differences. OM in psoriatics shows a higher frequency of pitting and periungual telangiectasis, while a lower frequency of yellow structureless areas and nail spikes under dermoscopy.

A case report

A sympathetic crashing pulmonary edema (SCAPE) is an emergency medical situation necessitating early recognition and treatment. We present a case of a 15-years old male who underwent a toenail excision of his left big toe and who developed SCAPE postoperatively. The low incidence of SCAPE intraoperatively makes it challenging for anesthesiologists to diagnose it. It occurs unexpectedly and precipitously, and it may increase the risks of morbidity and mortality if it is not treated promptly. Our aim is to raise awareness of how to abruptly manage such cases.

Onychoscopic characteristics of Trichophyton rubrum and Trichophyton interdigitalis fungal infections: A multicentric study

BACKGROUND

Trichophyton rubrum and Trichophyton mentagrophytes variant interdigitalis are the most frequent etiologic agents of onychomycosis. Diagnosis of certainty requires mycological examination, which often results unfeasible.

OBJECTIVES

The aim of our study is to describe pathogen specific dermoscopic features, allowing a differential diagnosis without the need for cultural examination, in order to prescribe the most appropriate treatment anyway.

PATIENTS AND METHODS

We conducted an observational retrospective study on 54 patients with a culture proven diagnosis of distal subungual onychomycosis of the toenail, caused by Trichophyton rubrum or Trichophyton mentagrophytes variant interdigitalis. Using a videodermatoscope we collected data on nail colour (white, yellow, orange, brown, dark) and on dermoscopic patterns (aurora, spikes, jagged, ruin, linear edge, dots, striae).

RESULTS

Fifty-four patients, with a total of 72 nails, were eligible for this study. Analysing the association between discoloration of the nail plate and type of infection (T. rubrum or T. interdigitalis), no correlation turned out to be statistically significant. Instead, significant associations between spikes and T. rubrum infection and striae and infection from T. interdigitalis were identified. Finally, a 100% specificity was identified for white colour and ruin pattern for T. rubrum infection, and brown colour, jagged border and aurora pattern for T. interdigitalis.

CONCLUSIONS

Trying to find relationships between specific pathogens and dermoscopic patterns, we found out an association between spikes and striae and T. rubrum and T. interdigitalis respectively. Further larger studies are however necessary to evaluate our preliminary findings.

Prevalence and Associated Factors of Toenail Onychomycosis Among Patients with Diabetes in Jordan

BACKGROUND

Toenail onychomycosis is common in patients with diabetes and it can increase the risk of secondary infections and foot complications. Despite several studies investigating the prevalence and associated factors of toenail onychomycosis from different parts of the world, there are no data from Jordan.

OBJECTIVE

To determine the prevalence and the associated factors of toenail onychomycosis among patients with diabetes in Jordan.

METHODS

A cross-sectional study was conducted on 375 patients with diabetes at the National Centre for Diabetes, Endocrinology, and Genetics in Amman, Jordan. Several socio-demographic and health-independent variables including foot self-care practices were collected. Toenail onychomycosis was assessed by a specimen culture and microscopic examinations. Descriptive and inferential statistics were used for data analysis.

RESULTS

The prevalence of toenail onychomycosis was 57.6% (n=216). Multiple logistic regression revealed four significant associated factors; the presence of neuropathy (β=1.87, p=0.02), being an ex-smoker (β=2.69, p=0.01), being treated by both insulin and oral hypoglycemics drugs (β=1.32, p=0.03), and using antibiotics in the last year (β=1.78, p=0.02).

CONCLUSION

The prevalence of toenail onychomycosis among patients with diabetes in Jordan is high. Regular foot screening and podiatric care are recommended especially among patients with diabetic neuropathy, current treatment by insulin and oral hypoglycemics drugs, previous history of smoking, and previous use of antibiotics.

On the Basis of Sex: Impact and Treatment of Toenail Onychomycosis in Female Patients

Onychomycosis is a fungal infection of the nail unit affecting approximately five percent of the global population and representing 50 percent of all nail dystrophies seen in clinical practice. Patients with onychomycosis can suffer significant pain in addition to physical and psychological distress, which may seriously impair their quality of life (QoL). It is well established that onychomycosis prevalence is impacted by patient characteristics, including age and systemic comorbidities. However, the impact of patient sex on onychomycosis occurrence and treatment is not well characterized. This narrative review of the literature was conducted to address a dearth of published information on epidemiology, QoL, clinical trial participation, and treatment success specifically in female patients with onychomycosis. Additionally, an analysis of real-world treatment of onychomycosis in female patients is reported, including prescription patterns and the impact of toenail polish on topical treatments for onychomycosis. Understanding sex as a clinically relevant variable may inform onychomycosis treatment strategies and improve treatment outcomes.

In vivo Guinea Pig Model Study for Evaluating Antifungal Effect of a Dual-Diode Laser with Wavelengths of 405 Nm and 635 Nm on Dermatophytosis

Background

Various laser- and light-based devices have been introduced as complementary or alternative treatment modalities for dermatophytosis, particularly for finger or toenail onychomycosis.

Objective

This study aimed to comparatively evaluate the antifungal effects of 405-nm and 635-nm dual-band diode lasers using an in vivo guinea pig model of dermatophytosis.

Materials and Methods

A guinea pig model was developed by the repetitive application of fungal spore preparations to the back skin of guinea pigs. Dual-diode laser treatment was delivered to the guinea pig skin at a power of 24 mW at a wavelength of 405 nm and 18 mW at 635 nm for 12 min. The treatments were administered three times weekly for 2 weeks, and a mycological study was performed.

Results

Mycological studies using scraped samples obtained from treatment groups A (N = 8) and B (N = 8) after dual-diode laser treatment revealed that seven of eight (87.5%) samples in each group had negative results for direct potassium hydroxide microscopy and fungal culture studies. Skin specimens from each infected laser-untreated guinea pig exhibited spongiotic psoriasiform epidermis with parakeratosis. Meanwhile, skin specimens from infected laser-treated guinea pigs in groups A and B demonstrated thinner epidermal thickness than those from infected untreated controls but thicker than those from uninfected treated controls without noticeable inflammatory cell infiltration in the dermis.

Conclusion

The guinea pig dermatophytosis model can be used to comparatively evaluate the efficacy and safety of various treatment modalities, including dual-diode lasers, for superficial fungal skin infection.

A new hope in the treatment of onychogryphosis due to acquired malalignment of great toenails due to: intramatrix dexpanthenol injection

Onychogryphosis is a form of nail deformity characterized by a distorted, yellowish-brown thickened nail plate that is skewed, grossly thickened, and partly curved like a ram's horn. Although onychogryphosis has been described for more than one hundred years, there is no curative treatment for onychogryphosis. Nonsurgical conservative procedures and nail avulsion with or without matricectomy are the common treatment procedures. The recurrence rate is high, so patients' needs are not met in many cases. Herein, we report for the first time the intramatrix injection of dexpanthenol in the treatment of onychogryphosis with excellent result.

Metal Exposures in Residents Living Near an Urban Oil Drilling Site in Los Angeles, California

Urban environmental justice communities are potentially exposed to multiple toxic metals, through contaminated air, soil, water, and food. However, information on metals and their sources is lacking. This study uses non-negative matrix factorization (NMF) in a community-based participatory research study to identify potential sources and to understand how these metals cluster in a population near an urban oil drilling site. We recruited 203 Latinx, Black, and Asian residents who lived within 1 km of an oil drilling site in south Los Angeles and collected toenail clippings to assess exposure to arsenic (As), cadmium (Cd), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and antimony (Sb). Using NMF, we identified three clusters based on concentrations in the participants' toenails. As, Cd, Pb, and Sb grouped together, indicative of an industrial source. A second grouping was composed of Ni and Mn, which may be related to oil drilling. We also identified a third source factor predominantly driven by Hg and As, which may arise from dietary sources. Utilizing NMF, a dimension reduction method, we identified a source factor high in Ni and Mn in residents living in a neighborhood near an active oil drilling site.

Estimation of elemental concentrations in the toenail of young Saudi females with obesity

Elemental homeostasis is essential for maintaining normal metabolic processes. Elements in the toenails are now considered in the diagnosis or screening and used as biomarkers of several metabolic disorders. The incidence of obesity is more prevalent in females than males globally. At the same time, females appeared more susceptible to elemental alterations than males. This study aimed to evaluate the variation in the levels of several elements in toenails as possible biomarkers of health conditions associated with obesity in young Saudi females. A cross-sectional study was performed, between February–November 2019. The study enrolled 79 young females divided into two groups: participants with obesity (n=39) and non-obese (n=40). The toenail was analyzed to estimate Fe, I, K, Na, Cd, Cr, Mn, Ca, Mg, Cu, Co, and Se levels. The study showed a significant elevation in the levels of Fe, Ca, K, and Na in the toenail sample of female participants with obesity compared to the non-obese group. The levels of Mn, Cd, Co, Cu, and Cr, were significantly decreased in the toenail of participants with obesity. Moreover, other elements (i.e., Mg, I, and Se) were not significantly lower in the female group with obesity. Our findings confirmed the alterations of several elements among Saudi females with obesity. The toenail elemental analysis may become a useful diagnostic technique in monitoring the nutritional status, predicting some metabolic disorders, and environmental exposure.

Biomarkers of disease in human nails: a comprehensive review

Diagnostic, monitoring, response, predictive, risk, and prognostic biomarkers of disease are all widely studied, for the most part in biological fluids or tissues, but there is steadily growing interest in alternative matrices such as nails. Here we comprehensively review studies dealing with molecular or elemental biomarkers of disease, as opposed to semiological, pharmacological, toxicological, or biomonitoring studies. Nails have a long history of use in medicine as indicators of pathological processes and have also been used extensively as a matrix for monitoring exposure to environmental pollution. Nail clippings are simple to collect noninvasively as well as to transport and store, and the matrix itself is relatively stable. Nails incorporate, and are influenced by, circulating molecules and elements over their several months of growth, and it is widely held that markers of biological processes will remain in the nail, even when their levels in blood have declined. Nails thus offer the possibility to not only look back into a subject's metabolic history but also to study biomarkers of processes that operate over a longer time scale such as the post-translational modification of proteins. Reports on ungual biomarkers of metabolic and endocrine diseases, cancer, and psychological and neurological disorders will be presented, and an overview of the sampling and analytical techniques provided.

Behavior of the electron spin resonance signals in X-ray irradiated human fingernails for the establishment of a dose reconstruction procedure

The retrospective dosimetry that follows accidental X-ray exposure is becoming more significant for improving radiation diagnosis and treatment. We investigated the dosimetric properties of electron spin resonance (ESR) signals in X-ray irradiated fingernails under conditions that resemble realistic situations. We collected fingernails from 12 Japanese donors between the ages of 30 to 70. The sampled fingernails were utilized for X-ray irradiation, mechanical stimulation and background measurements. We also collected 10 toenails from one of the donors to evaluate their differences from fingernails. Additionally, we prepared 15 samples from two donors to compare the signals generated by γ-rays to those by X-rays. After observing the linear dose-response for both X- and γ-ray irradiated samples, we found that the sensitivity of the air-absorbed dose of γ-ray irradiated samples was identical to that of X-ray irradiated samples. The effect from secondary electrons seemed to be small in fingernails. The inter-individual variation in the sensitivity was no greater than the intra-individual variation. The signal intensities in each measurement fluctuated about the linear response curve, and the size of the fluctuation was dependent on the sample. The average fluctuation corresponded to 1.7 Gy, and the standard deviation was 1.3 Gy. The signal induced by X-rays could be erased by soaking the samples in water and subsequently drying them for four days, which allowed us to estimate the signal intensity prior to the exposure. These characteristics of the ESR signal induced by X-rays facilitate the development of a feasible protocol for fingernail dose reconstruction.

Evaluating Onychomycosis Outcomes 2 Months into an 11-month-long Efinaconazole Regimen: The Role of Optical Coherence Tomography

BACKGROUND

Onychomycosis affects 43 million people in the United States and Europe. Topical therapies can be effective but require lengthy and costly regimens without an established method for predicting the treatment outcome.

OBJECTIVE

We studied the role of optical coherence tomography (OCT), a noninvasive imaging device approved by the United States Food and Drug Administration, in evaluating onychomycosis treatment outcomes.

METHODS

This investigator-initiated prospective clinical study recruited subjects from two urban medical centers. A total of 34 subjects with mild-to-moderate onychomycosis, confirmed using periodic acid-Schiff (PAS) staining, were treated with topical efinaconazole for 48 weeks, at which time a final PAS result was obtained.

RESULTS

A positive final PAS result was associated with fungal findings on OCT and with nonclearance of fungal findings by week 12. A negative final PAS was associated with the absence of fungal findings by week 12. OCT findings at Week 8 may suggest a 77% chance of mycological nonclearance or 82% chance of clearance. These predictive values are higher than the currently documented mycological cure rate of 54%. Clinical examination data had no predictive value alone or in concert with OCT.

CONCLUSION

We recommend OCT imaging be performed at the end of the second month of treatment to inform shared decision-making regarding whether or not to continue efinaconazole for nine additional months. OCT's ability to evaluate onychomycosis outcome in patients on topical efinaconazole both earlier and more reliably than nonimaging variables may improve the care given to and reduce the cost of onychomycosis for millions of patients.

Congenital malalignment of the great toenail: Conservative and definitive treatment

Congenital malalignment of the great toenail, or ungual malalignment, is a rarely recognized disorder. It is characterized by lateral deviation of the longitudinal axis of the nail plate with respect to the distal phalanx, and if untreated, complications in the late teens and adulthood may arise. In this study, we have reviewed conservative and definitive treatments for this disorder.

Onychomatricoma Presenting as a Dystrophic Right Great Toenail: Case Report and Review

Onychomatricoma is a rare, benign nail matrix tumor. It most frequently occurs on one of the first three fingers of the dominant hand or the big toe in middle-aged women. Our patient presented with a 10-year history of a progressive thickening of her right great toenail; it bled easily and was intermittently painful. She had experienced trauma to the nail prior to the onset of the dystrophy. MRI primarily showed inflammation localized to the nail bed without bony extension. Excisional biopsy, which included both the nail plate and matrix, established the diagnosis of onychomatricoma originating from the ventral nail matrix (lunula). Nail trauma or fungal infection may have a causative role in the pathogenesis of onychomatricoma. The nail plate can show splitting, increased curvature, or ridging; it can also present with yellow, red or brown, linear, pigmented bands. The clinical differential diagnosis of onychomatricoma includes fibrokeratoma, melanonychia, onychomycosis, periungual fibroma, and squamous cell carcinoma. Dermoscopic imaging shows parallel lesion edges and splinter hemorrhages; these dermoscopic features support the diagnosis of onychomatricoma over squamous cell carcinoma. Imaging such as ultrasound or MRI may suggest the diagnosis. Biopsy of the tumor is necessary to establish the diagnosis; the tumor may derive either from the ventral nail matrix (lunula) or from the ventral surface of the proximal nail fold. Histologic features vary depending not only on tumor origin but also on tissue orientation. Proximally, there is a fibroepithelial tumor consisting of fibrous stalk pierced by epithelial invaginations; the epithelium shows matrical differentiation containing basal and prekeratogenous cells. Distally, the tumor pierces the nail plate as glove-finger digitations; these digitations appear as discrete villi in the nail plate or show their negative image as multiple empty channels that have been described as “worm holes”. The channels may be epithelial lined and contain serous fluid. It is important to obtain an adequate biopsy specimen; the distinctive fibroepithelial histology might be inapparent in partial specimens lacking the epithelial invaginations. Immunohistochemical staining can distinguish onychomatricoma from tumors that can mimic its pathologic changes: fibromyxoma, neurofibroma, and perineurioma. Complete surgical excision is generally curative.

Clinical Observation and Follow-Up of Subungual Splinter Hemorrhages of Toenails in Chinese Adults

Background:

Subungual splinter hemorrhage (SSH) is a common nail disorder and is difficult to differentiate from other nail diseases because of their similar characteristics. The epidemiological study of SSH is lacking and it is unclear whether SSH needs treatment or not.

Aims:

The aims of this study were to observe the clinical characteristics of SSH of toenails in Chinese adults and to provide a reference for the diagnosis and prognosis of patients with SSH.

Materials and Methods:

We collected and followed up 63 SSH patients who were diagnosed through dermoscopic examination. The clinical and dermoscopic characteristics, disease course, and recovery results were recorded. Data sets were analyzed through the use of SPSS 16.0. Literature concerning SSH were reviewed and compared with the results in this study.

Results:

Sixty-three SSH patients were included with an age range of 17–58 years. Nearly 93.7% of SSH patients occurred in the right, left, or right and left first toenails; 66.7% of SSH patients occurred only in one toenail; there were 60.3% of SSH patients with a clear stimulus causing it and 31.8% of SSH patients with five types of comorbidities. The common characteristics of dermoscopy showed a reddish brown or brown stain with a clear boundary visible under the nail in which the color gradually faded outward from the center, with no blue or white structure. After following up for 24 weeks, the disappearance of hemorrhage was observed in 95.2% of SSH patients. For the recovered SSH patients, data analysis showed no significant difference in the course of SSH in males and females (P = 0.645); the statistical analysis showed that there was no significant correlation (r² = −0.002) between age and course in recovered SSH patients (P = 0.986).

Conclusions:

It is unnecessary to do any special treatment during the 1^st year. Measures ought to be taken for SSH patients if the course of the disease exceeds more than 1 year.

Recent advances in therapies for onychomycosis and its management

Onychomycosis is the most common affliction of the nail. It may be caused by dermatophytes, yeasts, and non-dermatophyte molds. Traditionally, oral antifungal treatments have been used to treat the fungus, although they can be accompanied by side effects and drug interactions. Topical treatments provide an alternative modality, bypassing the systemic effects of oral drugs; recent research has centered on topical drug improvement and development. Physical and laser treatments are being used in conjunction with topicals, which may help penetrate the thick nail plate. In this review, techniques from all categories are outlined: both novel experimental approaches and progress and effectiveness of recently developed treatments. More long-term studies are required to determine the efficacy of various treatments, but cure rates are improved when patients adhere to treatments and follow preventative measures to avoid disease recurrence.

Aggressive superficial acral fibromyxoma of the great toe: A case report and mini-review of the literature

Superficial acral fibromyxoma is a very rare soft tissue tumor. Fetsch et al first described the condition in 2001. It often occurs in the fingers and toes and has slow-progressive features. Since being described, a few cases occurring in the great toe have been reported. The present study indicated a case of a 37-year-old male kickboxer with a history of a rapid-growing lump under the nail of his left great toe with bone erosion. The patient was suspected to have a soft tissue tumor under the nail, such as a glomus tumor, as a differential diagnosis. However, a malignant soft tissue tumor as a differential diagnosis could not be ruled out because of the observed bone erosion. The patient underwent surgical excision, and pathologic analysis revealed superficial acral fibromyxoma. Twenty-four months after the treatment, he had no complaints or functional disorder and no recurrence was noted. Although an unusual diagnosis, surgeons should be aware of this tumor, which requires complete surgical excision and follow-up to detect recurrence. To the best of our knowledge, this is the first reported case of superficial acral fibromyxoma with bone erosion in a great toe.

Topical efinaconazole: A promising therapeutic medication for tinea unguium

We treated tinea unguium (onychomycosis caused by dermatophytes) patients with efinaconazole 10% solution. All patients with tinea unguium who tested positive for fungi in fingernails and toenails, regardless of age or severity, were eligible for the treatment. The number of patients was 106, consisting of 43 men and 63 women with a mean age of 66.7 years. The patients were treated with efinaconazole for a mean treatment duration of 38.1 weeks. Therapeutic efficacy was rated on a 5-point scale as follows: "cured", "markedly improved", "improved", "slightly improved" or "no change". A single nail was selected in each patient as the target nail. Selected nails were the big toenails with less than 50% involvement in 25 patients, the big toenails with 50% or more involvement in 52 patients, the fingernails in 10 patients and the second to fifth toenails in 19 patients with a mean treatment duration of 43.9, 38.1, 38.7 and 33.7 weeks, respectively. All groups showed an improvement in the percentage involvement from 30.6% to 9.8%, 77.6% to 35.7%, 82.7% to 17.6% and 80.3% to 15.5%, respectively (P < 0.01). The improvement rate (i.e. percentage of those rated as improved and better) was 76.0%, 65.4%, 80.0% and 89.5%, respectively. Efinaconazole 10% topical solution is beneficial for patients, regardless of age, severity or clinical type.

A Preliminary Evaluation of the Ability of Keratotic Tissue to Act as a Prognostic Indicator of Hip Fracture Risk

Studies have shown that Raman spectroscopic analysis of fingernail clippings can help differentiate between post-menopausal women who have and who have not suffered a fracture. However, all studies to date have been retrospective in nature, comparing the proteins in nails sourced from women, post-fracture. The objective of this study was to investigate the potential of a prospective test for hip fracture based on spectroscopic analysis of nail tissue. Archived toenail samples from post-menopausal women aged 50 to 63 years in the Nurses' Health Study were obtained and analysed by Raman spectroscopy. Nails were matched case-controls sourced from 161 women; 82 who underwent a hip fracture up to 20 years after nail collection and 81 age-matched controls. A number of clinical risk factors (CRFs) from the Fracture Risk Assessment (FRAX) tool had been assessed at toenail collection. Using 80% of the spectra, models were developed for increasing time periods between nail collection and fracture. Scores were calculated from these models for the other 20% of the sample and the ability of the score to predict hip fracture was tested in model with and without the CRFs by comparing the odds ratios (ORs) per 1 SD increase in standardised predictive values. The Raman score successfully distinguished between hip fracture cases and controls. With only the score as a predictor, a statistically significant OR of 2.2 (95% confidence interval [CI]: 1.5-3.1) was found for hip fracture for up to 20 years after collection. The OR increased to 3.8 (2.6-5.4) when the CRFs were added to the model. For fractures limited to 13 years after collection, the OR was 6.3 (3.0-13.1) for the score alone. The test based on Raman spectroscopy has potential for identifying individuals who may suffer hip fractures several years in advance. Higher powered studies are required to evaluate the predictive capability of this test.

Toenail mercury Levels are associated with amyotrophic lateral sclerosis risk

INTRODUCTION

Mercury is a neurotoxic metal that is potentially a risk factor for amyotrophic lateral sclerosis (ALS). Consumption of methylmercury contaminated fish is the primary source of US population exposure to mercury.

METHODS

We used inductively coupled plasma mass spectrometry to measure levels of mercury in toenail samples from patients with ALS (n = 46) and from controls (n = 66) as a biomarker of mercury exposure.

RESULTS

Patients with ALS had higher toenail mercury levels (odds ratio 2.49, 95% confidence interval 1.18-5.80, P = 0.024) compared with controls, adjusted for age and sex. We also estimated the amount of mercury consumed from finfish and shellfish and found toenail mercury levels elevated overall among patients with ALS and controls in the top quartile for consumption (P = 0.018).

DISCUSSION

Biomarker data show that ALS is associated with increased with mercury levels, which were related to estimated methylmercury intake via fish. Replication of these associations in additional populations is warranted. Muscle Nerve, 2018.

Quantification of manganese and mercury in toenail in vivo using portable X-ray fluorescence (XRF)

BACKGROUND AND OBJECTIVE

Toenail is an advantageous biomarker to assess exposure to metals such as manganese and mercury. Toenail Mn and Hg are in general analyzed by chemical methods such as inductively coupled plasma mass spectrometry and atomic absorption spectrophotometry. In this project, a practical and convenient technology-portable X-ray florescence (XRF)-is studied for the noninvasive in vivo quantification of manganese and mercury in toenail.

MATERIAL AND METHODS

The portable XRF method has advantages in that it does not require toenail clipping and it can be done in 3 min, which will greatly benefit human studies involving the assessment of manganese and mercury exposures. This study mainly focused on the methodology development and validation which includes spectral analysis, system calibration, the effect of toenail thickness, and the detection limit of the system. Manganese- and mercury-doped toenail phantoms were made. Calibration lines were established for these measurements.

RESULTS

The results show that the detection limit for manganese is 3.65 μg/g (ppm) and for mercury is 0.55 μg/g (ppm) using 1 mm thick nail phantoms with 10 mm soft tissue underneath.

DISCUSSION AND CONCLUSION

We conclude that portable XRF is a valuable and sensitive technology to quantify toenail manganese and mercury in vivo.

Stable isotopes can be used to infer the overwintering locations of prebreeding marine birds in the Canadian Arctic

Although assessments of winter carryover effects on fitness‐related breeding parameters are vital for determining the links between environmental variation and fitness, direct methods of determining overwintering distributions (e.g., electronic tracking) can be expensive, limiting the number of individuals studied. Alternatively, stable isotope analysis in specific tissues can be used as an indirect means of determining individual overwintering areas of residency. Although increasingly used to infer the overwintering distributions of terrestrial birds, stable isotopes have been used less often to infer overwintering areas of marine birds. Using Arctic‐breeding common eiders, we test the effectiveness of an integrated stable isotope approach (13‐carbon, 15‐nitrogen, and 2‐hydrogen) to infer overwintering locations. Knowing the overwinter destinations of eiders from tracking studies at our study colony at East Bay Island, Nunavut, we sampled claw and blood tissues at two known overwintering locations, Nuuk, Greenland, and Newfoundland, Canada. These two locations yielded distinct tissue‐specific isotopic profiles. We then compared the isotope profiles of tissues collected from eiders upon their arrival at our breeding colony, and used a k‐means cluster analysis approach to match arriving eiders to an overwintering group. Samples from the claws of eiders were most effective for determining overwinter origin, due to this tissue's slow growth rate relative to the 40‐day turnover rate of blood. Despite taking an integrative approach using multiple isotopes, k‐means cluster analysis was most effective when using 13‐carbon alone to assign eiders to an overwintering group. Our research demonstrates that it is possible to use stable isotope analysis to assign an overwintering location to a marine bird. There are few examples of the effective use of this technique on a marine bird at this scale; we provide a framework for applying this technique to detect changes in the migration phenology of birds' responses to rapid changes in the Arctic.

The Gulf Long-Term Follow-Up Study (GuLF STUDY): Biospecimen collection at enrollment

The 2010 Deepwater Horizon (DWH) explosion in the Gulf of Mexico led to the largest ever marine oil spill by volume. The GuLF STUDY is investigating possible adverse human health effects associated with oil spill activities. One objective of the study was to utilize biological specimens from study participants to examine spill-related adverse health effects. This study describes the methods for collecting, processing, shipping, and storing specimens during the enrollment phase of the study. GuLF STUDY participants living in Gulf States (Alabama, Florida, Louisiana, Mississippi, and eastern Texas) were eligible to complete a home visit at enrollment, one to three years after the DWH explosion. During this visit, blood, urine, toenail and hair clippings, and house dust samples were collected. Specimens were shipped overnight to a central processing laboratory in containers with cold and ambient temperature compartments. Most blood and urine specimens were then aliquoted and stored in liquid nitrogen vapor or at -80°C, with some samples stored at -20°C. A total of 11,193 participants completed a home visit, and over 99% provided at least one biospecimen. Most participants provided blood (93%), urine (99%), and toenail clippings (89%), and 40% provided hair. Nearly all participants (95%) provided house-dust samples. Most samples were received by the laboratory one (58%) or two (25%) days after collection. These biospecimens enable investigation of a range of biomarkers of spill-related adverse health effects, and possibly some biomarkers of spill-related exposures. The biospecimen collection, handling, and storage protocols were designed to maximize current and future scientific value within logistical and budgetary constraints and might serve as a template for future studies conducted in similar time-critical and geographically dispersed settings.

Scanning electron microscopy of the nail plate in onychomycosis patients with negative fungal culture

Onychomycosis is a common dermatological problem and can be identified by direct microscopic examination and fungal culture. However, the positive rate of fungal culture is low. This study investigated the application of scanning electron microscopy in the diagnosis of onychomycosis in 20 patients with negative fungal culture. In this study, a routine glutaraldehyde fixation method was used to prepare specimens for electron microscope examination. Results showed that under the scanning electron microscope, significant structural damage was observed in the nail plate in all patients. Hyphaes were seen in 70% of cases. A mixture of scattered hyphaes, pseudohyphaes, and spores was observed in 30% of cases. A mixture of spores and bacteria was observed in 10% of cases. A mixture of hyphaes and bacteria was observed in 20% of cases. The typical hyphae pierced a thin layer or single layer of corneocytes. Hyphaes could be smooth, sleek, and straight with visible separation, or dry, bent, and folded with a smooth surface. The diameter of hyphaes was 1-2 µm. The scattered spores were the main form of spore growth, and the growth of budding spores can be seen attached to the surface of layered armor. Most of the bacteria were gathered in clumps on the ventral surface, especially in grooves. In conclusion, scanning electron microscopy can be used to preliminarily identify the pathogen involved and the degree of damage in cases where onychomycosis is clinically diagnosed, but fungal culture is negative.

Relations of biomarkers of manganese exposure and neuropsychological effects among welders and ferroalloy smelters

The objective of present study was to assess relationship between biomarkers of Manganese (Mn) and neuropsychological effects. The study was carried out on 27 welders and 31 ferroalloy smelters as Mn-exposed groups and 30 office workers as unexposed controls. Air Mn concentrations were determined according to NIOSH method 7300. The biological samples were prepared using microwave assisted acid digestion and all samples were analyzed by graphite furnace- atomic absorption spectroscopy (GF-AAS) in order to determine manganese. Questionnaire 16 (Q16) and Cambridge Neuropsychological Test Automated Battery (CANTAB) were used to evaluate the neuropsychological effects. The mean concentrations of air Mn for the welder and ferroalloy smelter groups were 0.023 ± 0.012 mg/m(3) and 0.008 ± 0.005 mg/m(3), respectively. Manganese concentrations in blood, urine, and toenail samples of exposed workers ranged between 1.80-32.60 (µg/l), 1.00-42.50 (µg/l), and 0.10-6.08 (µg/g), respectively. Mean Mn concentrations in all biological samples of cases were significantly higher than unexposed controls (p<0.05). A moderate relationship was observed between biomarkers of Mn exposure, air Mn, Q16 as well as some neurocognitive outcome measures. The present study shows that blood Mn, urine Mn and toenail Mn could be used to distinguish Mn-exposed workers from unexposed population at the group level.

Efinaconazole 10% topical solution for the topical treatment of onychomycosis of the toenail

Efinaconazole 10% topical solution is a new antifungal therapy for the topical treatment of mild to moderate toenail onychomycosis. In vitro and in vivo data have shown significant antifungal activity against dermatophytes, Candida spp. and nondermatophyte molds, and its mechanism of action is through inhibition of fungal lanosterol 14α-demethylase. In two parallel, double-blind, randomized, controlled, Phase III trials, complete cure rates were 17.8 and 15.2%, respectively, and mycological cure rates were 55.2 and 53.4%, respectively, for efinaconazole 10% topical solution, which were superior to vehicle, with minimal adverse events. This drug profile reviews the most recent basic science and clinical data for efinaconazole in the treatment of toenail onychomycosis.

Efinaconazole Topical Solution, 10%: Factors Contributing to Onychomycosis Success

To provide an adequate therapeutic effect against onychomycosis, it has been suggested that topical drugs should have two properties: drug permeability through the nail plate and into the nail bed, and retention of their antifungal activity in the disease-affected areas. Only recently has the importance of other delivery routes (such as subungual) been discussed. Efinaconazole has been shown to have a more potent antifungal activity in vitro than the most commonly used onychomycosis treatments. The low keratin affinity of efinaconazole contributes to its effective delivery through the nail plate and retention of its antifungal activity. Its unique low surface tension formulation provides good wetting properties affording drug delivery both through and under the nail. High antifungal drug concentrations have been demonstrated in the nail of onychomycosis patients, and effectiveness of efinaconazole topical solution, 10% confirmed in two large well-controlled multicenter Phase 3 clinical studies in patients with mild-to-moderate disease.

Clinico-mycological study of dermatophyte toenail onychomycosis in new delhi, India

Introduction:

There is a constant need to define the epidemiological and mycological characteristics of onychomycosis (OM) for optimal management strategies.

Objectives:

To define the epidemiological and mycological characteristics of patients with dermatophyte toenail OM in a tertiary care hospital.

Materials and Methods:

Hundred consecutive patients of KOH and culture-positive dermatophyte toenail OM were subjected to detailed history, clinical examination and investigations.

Results:

Maximum number of patients (40%) belonged to 31-45 years age group and there was a male preponderance (M:F = 6.7:1). The mean duration of disease was 54 months. Thirty-three patients had fingernail involvement in addition to the toenail OM and 37% had co-existent cutaneous dermatophyte infection. Discoloration was the most common symptom (98%). Ninety-four (94%) patients had distal lateral subungual onychomycosis (DSLO) while two had superficial onychomycosis (SO) and only one had proximal superficial onychomycosis (PSO). Trichophyton interdigitale was the most common etiological agent (61%) followed by Trichophyton rubrum and Trichophyton verrucosum.

Conclusions:

Toenail OM is more common in males. DSLO was the most common clinical variant and T. interdigitale the most common etiological fungus responsible for toenail OM in our region. The importance of early diagnosis and treatment is highlighted as long-standing toenail OM predisposes to fingernail onychomycosis and recurrent tinea pedis.

Distributions and determinants of mercury concentrations in toenails among American young adults: the CARDIA Trace Element Study

Since data on mercury (Hg) levels in Caucasians and African Americans (AAs) of both genders are lacking, this study aims to present toenail Hg distributions and explore the potential determinants using data from the Coronary Artery Risk Development in Young Adults Trace Element Study. Data from 4,344 Americans, aged 20-32 in 1987, recruited from Oakland, Chicago, Minneapolis, and Birmingham were used to measure toenail Hg levels by instrumental neutron-activation method. The Hg distribution was described with selected percentiles and geometric means. Multivariable linear regression (MLR) was used to examine potential determinants of Hg levels within ethnicity-gender subgroups. The geometric mean of toenail Hg was 0.212 (95 % CI = 0.207-0.218) μg/g. Hg levels varied geographically with Oakland the highest [0.381 (0.367-0.395) μg/g] and Minneapolis the lowest [0.140 (0.134-0.147) μg/g]. MLR analyses showed that male gender and AA ethnicity were negatively associated with toenail Hg levels, and that age, living in Oakland city, education level, alcohol consumption, and total fish intake were positively associated with toenail Hg concentrations within each ethnicity-gender subgroup. Current smokers were found to have higher Hg only in AA men. This study suggested age, gender, ethnicity, study center, alcohol, education level, and fish consumption consistently predict toenail Hg levels. As fish consumption was the key determinant, avoiding certain types of fish that have relatively high Hg levels may be crucial in reducing Hg intake.

Chronologically matched toenail-Hg to hair-Hg ratio: temporal analysis within the Japanese community (U.S.)

BACKGROUND

Toenail-Hg levels are being used as a marker of methylmercury (MeHg) exposure in efforts to associate exposure with effects such as cardiovascular disease. There is a need to correlate this marker with more established biomarkers that presently underlie existing dose-response relationships in order to compare these relationships across studies.

METHODS

As part of the Arsenic Mercury Intake Biometric Study, toenail clippings were collected at three time points over a period of one year amongst females from within the population of Japanese living near Puget Sound in Washington State (US). Variability in temporal intra-individual toenail-Hg levels was examined and chronologically matched hair and toenail samples were compared to more accurately define the toxicokinetic variability of Hg levels observed between the two compartments.

RESULTS

Mean toenail-Hg values (n=43) for the 1st, 2nd and 3rd visits were 0.60, 0.60 and 0.56 ng/mg. Correlations were as follows: r=0.92 between 1st and 2nd clinic visits, r=0.75 between 1st and 3rd visits and r=0.87 between 2nd and 3rd visits. With few exceptions, toenail-Hg values from any visit were within 50-150% of the individual's mean toenail-Hg level. Nearly all participants had less than a two-fold change in toenail-Hg levels across the study period. A regression model of the relationship between toenail-Hg and hair-Hg (n = 41) levels representing the same time period of exposure, gave a slope (Hg ng/mg) of 2.79 for hair relative to toenail (r=0.954).

CONCLUSIONS

A chronologically matched hair-Hg to toenail-Hg ratio has been identified within a population that consumes fish regularly and in quantity. Intra-individual variation in toenail-Hg levels was less than two-fold and may represent dietary-based fluctuations in body burden for individuals consuming various fish species with different contaminant levels. The chronologically matched ratio will be useful for relating MeHg exposure and dose-response derived from toenail-Hg measurements to those derived from hair-Hg measurements in other studies, and may be useful in future investigations as an indicator of stable MeHg body burden within a population.

Demographic and lifestyle factors and selenium levels in men and women in the U.S

Selenium is an antioxidant trace element linked to cardiovascular disease and cancer. Although diet is a major source, relatively little else is known about independent determinants of selenium levels in free-living humans. In this study, we aimed to investigate the independent demographic, lifestyle, and dietary determinants of selenium levels in 1,997 men and 1,905 women in two large prospective U.S. cohorts. Toenail selenium levels were quantified using neutron activation analysis. Diet, geographic residence, demographic, and environmental factors were assessed by validated self-administered questionnaires. Multivariate generalized linear models were conducted to assess the independent relations of these factors with toenail selenium levels, correcting for measurement error in the diet. In multivariable-adjusted analyses, independent predictors of higher selenium were male gender (6.3% higher levels); living in West and Northern-Midwest U.S. regions (8.9% and 7.4% higher than Southern-Midwest regions, respectively); consumption of beef and bread products (between 0.7 - 2.5% higher per daily serving); and selenium supplement use (6.9% higher than non-users); whereas cigarette smoking (5-10% lower than never smokers) , older age (0.6% lower per 5 years), and consumption of eggs, white rice, dairy products, coffee, and alcohol (between 0.1 to 2.0% lower per daily serving) were associated with lower selenium. Multiple dietary and non-dietary factors independently predicted selenium levels, suggesting that both consumption and non-dietary processes (e.g., related to oxidant status) may affect levels. Significant geographic variation in selenium levels exists in the US.

Distribution of toenail selenium levels in young adult Caucasians and African Americans in the United States: the CARDIA Trace Element Study

BACKGROUND

Data on selenium (Se) levels in American young adults, especially in African Americans, are lacking.

OBJECTIVE

This study presented toenail Se distributions in American young adults of both genders, including both Caucasians and African Americans; and explored potential predictors of toenail Se levels.

DATA AND METHODS

Data from the Coronary Artery Risk Development in Young Adults study among 4252 American young adults, aged 20-32 in 1987 was used to examine toenail Se levels by instrumental neutron-activation analysis. The distribution of Se levels was described and multivariable linear regression was used to examine potential modifiers of toenail Se concentration within ethnicity-gender subgroups.

RESULTS

The geometric mean of toenail Se in this cohort was 0.844 μg/g (95% CI, 0.840-0.849 μg/g) and the median was 0.837 μg/g (95% CI, 0.833-0.844 μg/g). Median levels from lowest to highest quintile were 0.691, 0.774, 0.838, 0.913 and 1.037 μg/g. Se levels varied geographically, and were generally in accordance with its concentrations in local soil. Males, African Americans, current smokers, heavy drinkers and less educated participants were more likely to have low Se levels.

CONCLUSION

This study suggests that toenail Se levels vary geographically depending on soil Se concentrations. In addition to gender, ethnicity and education level, smoking status and alcohol consumption are two important indicators of Se status since they are modifiable lifestyle factors. Findings from this study might aid public health professionals in identifying people at relatively high or low Se levels, so that chronic disease prevention efforts can be directed toward these subgroups.