The prevalence, aetiological agents and therapy of onychomycosis in patients with psoriasis: a prospective controlled trial

The Prevalence of Onchomycosis in Psoriasis Patients: A Systematic Review and Meta-Analysis

INTRODUCTION

Onychomycosis, a common nail disease characterised by thickened, discoloured and brittle nails, has been observed to have varying prevalence rates in psoriasis patients compared to the general population. Psoriasis is a chronic autoimmune condition affecting approximately 2%-3% of the global population, with nail involvement impacting up to 79% of these patients. The clinical features of onychomycosis and nail psoriasis often overlap, complicating accurate diagnosis. This systematic review and meta-analysis aims to evaluate whether the prevalence of onychomycosis differs between psoriasis patients and non-psoriasis individuals, thereby providing evidence-based insights for clinical practice.

METHODS

The research question and keywords were developed following the Population, Intervention, Comparator, and Outcome (PICO) framework. As of October 26, 2024, records in English or Chinese were obtained from PubMed, Embase, Cochrane Library, CNKI, CBM and Web of Science, using the keywords "onychomycosis," "psoriasis," etc. Furthermore, the meta-analysis was carried out with STATA.

RESULTS

A total of 967 records were identified, with 13 studies comprising 2751 psoriasis patients and 10,967 non-psoriasis individuals included in the final analysis. The meta-analysis revealed that psoriasis patients had a significantly higher prevalence of onychomycosis, 1.68 times greater than those without psoriasis (95% CI: 1.21-2.33). Subgroup analysis showed that among clinically unsuspected patients, the risk of onychomycosis in those with psoriasis was 1.78 times higher (95% CI: 1.33-2.38) than in non-psoriasis individuals. The majority of the studies included were of moderate to low bias.

CONCLUSION

The prevalence of onychomycosis is significantly higher in psoriasis patients compared to those without. However, limitations in research methods, variability in study populations, and small sample sizes in some studies suggest that further investigation is necessary. Future research should employ standardised methodologies, larger sample sizes, and long-term follow-up to enhance the accuracy and reliability of findings. Based on the results of this review and meta-analysis, it is crucial to rule out onychomycosis-related nail lesions before diagnosing psoriasis, especially prior to initiating immunosuppressive treatments such as steroids, methotrexate, or biologics, as these may exacerbate fungal infections.

PROTOCOL REGISTRATION

PROSPERO-CRD42023399195.

Retrospective Analysis of Onychomycosis Risk Factors Using the 2003-2014 National Inpatient Sample

INTRODUCTION

Onychomycosis, a fungal nail infection, is associated with significant morbidity and negative impact on quality of life. Therefore, understanding associated risk factors may inform onychomycosis screening guidelines.

OBJECTIVES

This retrospective study investigated common demographic and comorbidity risk factors among hospitalized patients using the National Inpatient Sample.

METHODS

The 2003-2014 National Inpatient Sample (NIS) database was used to identify onychomycosis cases and age and sex matched controls in a 1:2 ratio. Chi-square tests and T-tests for independent samples were utilized to compare categorical and continuous patient factors. Demographic and comorbidity variables significant (P < 0.05) on univariate analysis were analyzed via a multivariate regression model with Bonferroni correction (P < 0.0029).

RESULTS

119,662 onychomycosis cases and 239,324 controls were identified. Compared to controls, onychomycosis patients frequently were White (69.0% versus 68.0%; P < 0.001), Black (17.9% versus 5.8%; P < 0.0001), and insured by Medicare or Medicaid (80.1% versus 71.1%; P < 0.0001). Patients had greater hospital stays (9.69 versus 5.39 days; P < 0.0001) and costs ($39,925 versus $36,720; P < 0.001) compared to controls. On multivariate analysis, onychomycosis was commonly associated with tinea pedis (odds ratio [OR]: 111.993; P < 0.0001), human immunodeficiency virus (OR: 4.372; P < 0.001), venous insufficiency (OR: 6.916; P < 0.0001), and psoriasis (OR: 3.668; P < 0.001).

CONCLUSIONS

Onychomycosis patients had longer hospital stays and greater costs compared to controls. Black patients were disproportionately represented among cases compared to controls. Onychomycosis was associated with tinea pedis, venous insufficiency, human immunodeficiency virus, psoriasis, obesity (body mass index [BMI] ≥ 30 kg/m2), peripheral vascular disease, and diabetes with chronic complications, suggesting that inpatients with onychomycosis should be screened for these conditions.

Overall Prevalence and Prevalence Compared among Psoriasis Treatments of Onychomycosis in Patients with Nail Psoriasis and Fungal Involvement

BACKGROUND

Whether nail psoriasis can increase the risk of onychomycosis is still being debated, and data relating to the prevalence of onychomycosis among psoriasis patients receiving different treatments is limited.

OBJECTIVES

To investigate the overall prevalence and prevalence compared among psoriasis treatments of onychomycosis in patients with nail psoriasis and fungal involvement.

METHODS

A prospective study of three groups of nail psoriasis being treated with only topical medication, methotrexate, or biologics (25 patients per group, 150 nails) was conducted at Siriraj Hospital (Bangkok, Thailand) during November 2018 to September 2020. Demographic data, psoriasis severity, and nail psoriasis severity were recorded. The nail most severely affected with psoriasis on each hand was selected for mycological testing. Potassium hydroxide, periodic acid-Schiff stain, and fungal culture were performed.

RESULTS

The prevalence of onychomycosis in nail psoriasis was 35.3%. Among the treatment groups, the prevalence of onychomycosis was significantly higher in the methotrexate group than in the topical treatment and biologic treatment groups (p = 0.014). Candida spp. was the main causative organism, followed by Trichophyton rubrum. Thumb was most commonly affected (59.3%). The most common abnormality of the nail matrix and the nail bed was pitted nail (71.3%) and onycholysis (91.3%), respectively. Multivariate analysis revealed diabetes, wet-work exposure, and methotrexate treatment to be predictors of onychomycosis.

CONCLUSIONS

Several factors, including psoriasis treatment, were shown to increase the risk of onychomycosis in nail psoriasis. Further research is needed to determine whether biologic agents, especially interleukin-17 inhibitors, can increase risk of onychomycosis and Candida infection/colonization of the nails.

Coexistence of onychomycosis and nail psoriasis and its correlation with systemic treatment

BACKGROUND

Epidemiological studies indicate that onychomycosis may affect up to 79% of psoriatic patients. Onychomycosis in psoriatic patients is more commonly caused by yeasts comparing with non-psoriatic.

OBJECTIVES

Evaluate the prevalence of fungi in nail psoriasis. Evaluate the association between direct mycological examination (DME) and mycological culture, Nail Psoriasis Severity Index (NAPSI) and systemic treatment for psoriasis.

METHODS

Of 133 nails from 20 patients with nail psoriasis were evaluated as follows: 9 patients were using topical treatment and 11 were on systemic treatment. The assessment of psoriasis severity using NAPSI was performed in all psoriatic nails. The presence of fungi was confirmed in DME and culture.

RESULTS

DME showed the presence of fungal elements in 45 nails (33.83%) with a predominance of blastoconidia (95.5%) No septate hyphae were seen. Mycological culture was positive in 36 (27.06%) samples. Among them, Candida grew in 31 (86.1%): Candida parapsilosis in 15 (48.38%), Candida spp in 14 (45.16%). No growth of dermatophytes was observed. Patients with systemic treatment showed a higher frequency of positive test (DME and culture) for fungi when compared to topic treatment (p:.006). There was a positive correlation between NAPSI, mycological culture and systemic treatment (p:.0063); the risk was four times higher (OR:4.0).

LIMITATION OF THE STUDY

Sample size.

CONCLUSION

These results are consistent with some previous reports, Candida was the fungus with higher frequency on the psoriatic nails, however, the role of these fungi is controversial (contamination x colonisation x infection). The fact that the immunosuppressive treatment increases the chance of fungal infection leads us to a greater attention to this patient profile, to prevent the intensification of nail psoriasis (Köbner phenomenon).

Nail Involvement in Psoriatic Patients and Association with Onychomycosis: Results from a Cross-Sectional Study Performed in a Military Hospital in Tunisia

Nail psoriasis has variable prevalence and heterogeneous aspects. Many of them could mimic onychomycosis (OM). It has been suggested that patients with nail psoriasis are at high risk of OM. The aim of our study was to determine the epidemiological and clinical characteristics of nail psoriasis and to estimate the frequency and the factors associated with OM in psoriatic patients. The studied group included 163 patients with psoriasis aged 18 years or older. Epidemiological and clinical data, as well as the severity of skin and nails disease by evaluating the Psoriasis Area Severity Index (PASI) and Nail Area Psoriasis Severity Index (NAPSI) scores were specified. Mycological testing was performed for patients with nail alterations. Nail involvement was found in 71.2% of patients. The most common nail alterations were subungual hyperkeratosis and onycholysis. The mean NAPSI score was 11.6. Mycological testing was performed in 104 patients with onychodystrophy. OM was diagnosed in 53% of the cases. Dermatophytes were the most isolated pathogens. OM was associated with male gender, but not with age, NAPSI, or PASI score. Psoriasis is one of the dermatoses that most commonly affect the nail. Available data about the association between nail psoriasis and OM are controversial. However, mycological testing should be routinely performed on psoriatic nails.

The prevalence and etiological factors of onychomycosis in psoriatic patients

Introduction

The role of a number of inherited, acquired and environmental factors has been identified to increase the risk of onychomycosis. The literature data on psoriasis as a risk factor are contradictory. The potential relationship between these pathologies is very important as it influences the patient management.

Aim

To evaluate the frequency of onychomycosis and etiological factors in patients with psoriasis compared to controls.

Material and methods

The studied group (n = 2427) included 2325 patients with nail abnormalities raising a clinical suspicion of nail onychomycosis (with no history of psoriasis) and 102 psoriatic inpatients. The control group included 100 patients with clinically normal nails. The assessment of psoriasis severity using Nail Psoriasis Severity Index (NAPSI) and Psoriasis Area and Severity Index (PASI) was performed in all psoriatic patients. The presence of fungi was confirmed in direct microscopy and culture.

Results

A significantly higher incidence of onychomycosis was observed in psoriatic patients as well as in non-psoriatic patients with clinically abnormal nails compared to controls. The prevalence of onychomycosis did not differ significantly between psoriatic patients and non-psoriatic patients with nail alterations. The characteristics of isolated fungi differed significantly between psoriatic and non-psoriatic patients. NAPSI ≥ 40 and receiving systemic treatment increased the risk of onychomycosis in psoriatic patients.

Conclusions

The presented study showed a relatively high prevalence of onychomycosis in patients with psoriasis, what confirms the accuracy of performing screening mycological examination in this group. Further studies are warranted to evaluate the role of specific risk factors, explain the differences observed in previous studies and to determine optimal patient management.

The Dermatologist's Approach to Onychomycosis

Onychomycosis is a fungal infection of the toenails or fingernails that can involve any component of the nail unit, including the matrix, bed, and plate. It is a common disorder that may be a reservoir for infection resulting in significant medical problems. Moreover, onychomycosis can have a substantial influence on one's quality of life. An understanding of the disorder and updated management is important for all health care professionals. Aside from reducing quality of life, sequelae of the disease may include pain and disfigurement, possibly leading to more serious physical and occupational limitations. Dermatologists, Podiatrists, and other clinicians who treat onychomycosis are now entering a new era when considering treatment options-topical modalities are proving more effective than those of the past. The once sought after concept of viable, effective, well-tolerated, and still easy-to-use monotherapy alternatives to oral therapy treatments for onychomycosis is now within reach given recent study data. In addition, these therapies may also find a role in combination and maintenance therapy; in order to treat the entire disease the practitioner needs to optimize these topical agents as sustained therapy after initial clearance to reduce recurrence or re-infection given the nature of the disease.

An in vitro study of the antimicrobial effects of indigo naturalis prepared from Strobilanthes formosanus Moore

Indigo naturalis is effective in treating nail psoriasis coexisting with microorganism infections. This study examines the antimicrobial effects of indigo naturalis prepared from Strobilanthes formosanus Moore. Eight bacterial and seven fungal strains were assayed using the agar diffusion method to examine the effects of indigo naturalis and its bioactive compounds. The bioactive compounds of indigo naturalis were purified sequentially using GFC, TLC, and HPLC. Their structures were identified using mass spectrometry and NMR spectroscopy. UPLC-MS/MS was applied to compare the metabolome profiles of indigo naturalis ethyl-acetate (EA) extract and its source plant, Strobilanthes formosanus Moore. The results of in vitro antimicrobial assays showed that indigo naturalis EA-extract significantly (≥1 mg/disc) inhibits Gram-positive bacteria (Staphylococcus aureus, S. epidermis and methicillin-resistant S. aureus (MRSA)) and mildly inhibits non-dermatophytic onychomycosis pathogens (Aspergillus fumigates and Candida albicans), but has little effect on dermatophyes. Isatin and tryptanthrin were identified as the bioactive compounds of indigo naturalis using S. aureus and S. epidermis as the bioassay model. Both bioactive ingredients had no effect on all tested fungi. In summary, indigo naturalis prepared from Strobilanthesformosanus Moore exhibits antimicrobial effects on Staphylococcus and non-dermatophytic onychomycosis pathogens. Tryptanthrin and isatin may be its major bioactive ingredients against Staphylococcus and the inhibitory effect on MRSA may be due to other unidentified ingredients.

[Fungal nail infections--an update: Part 1--Prevalence, epidemiology, predisposing conditions, and differential diagnosis]

Onychomycosis describes a chronic fungal infection of the nails most frequently caused by dermatophytes, primarily Trichophyton rubrum. In addition, yeasts (e. g. Candida parapsilosis), more rarely molds (Scopulariopsis brevicaulis), play a role as causative agents of onychomycosis. However, in every case it has to be decided if these yeasts and molds are contaminants, or if they are growing secondarily on pathological altered nails. The point prevalence of onychomycosis in Germany is 12.4%, as demonstrated within the "Foot-Check-Study", which was a part of the European Achilles project. Although, onychomycosis is rarely diagnosed in children and teens, now an increase of fungal nail infections has been observed in childhood. More and more, diabetes mellitus becomes important as significant disposing factor both for tinea pedis and onychomycosis. By implication, the onychomycosis represents an independent and important predictor for development of diabetic foot syndrome and foot ulcer. When considering onychomycosis, a number of infectious and non-infectious nail changes must be excluded. While psoriasis of the nails does not represent a specific risk factor for onychomycosis, yeasts and molds are increasing isolated from patients with psoriatic nail involvement. In most cases this represents secondary growth of fungi on psoriatic nails. Recently, stigmatization and impairment of quality of life due to the onychomycosis has been proven.