Onychomycosis and other superficial fungal infections of the foot in the elderly: a pan-European survey

BACKGROUND: The escalating ageing population in the western world has led to an increased incidence of superficial fungal infections. The most common infections include onychomycosis, tinea pedis and tinea cruris. With the increasing life expectancy, the prevalence of onychomycosis and other superficial fungal infections is likely to increase further without adequate prevention and treatment. Objective: To study the prevalence of foot mycoses in Europe. METHOD: The Achilles project represents a survey of 90,085 subjects from 16 European countries. RESULTS: Approximately half of the total screened population had evidence of fungal foot infection, with tinea pedis and onychomycosis affecting one quarter of these individuals. Advancing age showed an unfavourable effect on the prevalence of these infections. CONCLUSION: As the number of aged people in developed countries continues to increase, skin diseases will constitute a greater pharmaco-economic concern of worldwide healthcare. Better recognition by clinicians and patients of mycotic foot disease will help prevent direct morbidity and further complications.     

65751例真菌病患者病种及其致病菌种分析

目的：明确我院就诊患者中真菌病种及其致病菌种的分布。方法：对我院皮肤性病门诊2012年4月-2016年8月拟诊为真菌感染的65751例患者中真菌检查阳性的患者临床资料及分离的致病菌株资料进行回顾性分析。结果：65751例中直接镜检和（或）培养阳性22855例,阳性率35%。 共包括11个病种,患病人数前三位的病种为足癣5054例,甲真菌病3866例,股癣3071例。共分离出致病真菌5884株,前三位为红色毛癣菌3794株（64.46%）,念珠菌943株（16.03%）,第三是须癣毛癣菌558株（9.48%）。结论：我院真菌病患者中足癣、甲真菌病和股癣是最重要的病种,常见菌种为兼顾毛癣菌和念珠菌。     

Prevalence of superficial fungal infections among sports-active individuals: results from the Achilles survey, a review of the literature

OBJECTIVE: To examine the effect of sport activities on the prevalence of foot disease in the Achilles survey, conducted during the spring of 1997 and 1998 in several European countries. SUBJECT: Foot diseases, especially fungal infections (tinea pedis and onychomycosis). METHODS: A questionnaire and a clinical examination regarding individuals presenting to a general practitioner for disorders irrespective of possible foot problems. RESULTS: More than 50% of subjects visiting a general practitioner had clinical evidence of foot disease, and approximately two-thirds of these had clinical evidence of a superficial fungal infection. The survey evidenced a significant age-dependent association between sporting activities and the prevalence of foot diseases and superficial fungal infection, especially in children. CONCLUSIONS: The results of this pan-European survey indicate that sporting activities can have an unfavourable effect on the individual regarding the occurrence of foot disease and superficial fungal infection. The results indicate a need to pay more attention to foot disease, to predict and prevent future diseases and further complications.     

Onychomycosis in Children: An Experience of 59 Cases

Background

Although tinea unguium in children has been studied in the past, no specific etiological agents of onychomycosis in children has been reported in Korea.

Objective

The purpose of this study was to investigate onychomycosis in Korean children.

Methods

We reviewed fifty nine patients with onychomycosis in children (0~18 years of age) who presented during the ten-year period between 1999 and 2009. Etiological agents were identified by cultures on Sabouraud''s dextrose agar with and without cycloheximide. An isolated colony of yeasts was considered as pathogens if the same fungal element was identified at initial direct microscopy and in specimen-yielding cultures at a follow-up visit.

Results

Onychomycosis in children represented 2.3% of all onychomycosis. Of the 59 pediatric patients with onychomycosis, 66.1% had toenail onychomycosis with the rest (33.9%) having fingernail onychomycosis. The male-to-female ratio was 1.95:1. Fourteen (23.7%) children had concomitant tinea pedis infection, and tinea pedis or onychomycosis was also found in eight of the parents (13.6%). Distal and lateral subungual onychomycosis was the most common (62.7%) clinical type. In toenails, Trichophyton rubrum was the most common etiological agent (51.3%), followed by Candida albicans (10.2%), C. parapsilosis (5.1%), C. tropicalis (2.6%), and C. guilliermondii (2.6%). In fingernails, C. albicans was the most common isolated pathogen (50.0%), followed by T. rubrum (10.0%), C. parapsilosis (10.0%), and C. glabrata (5.0%).

Conclusion

Because of the increase in pediatric onychomycosis, we suggest the need for a careful mycological examination of children who are diagnosed with onychomycosis.     

Prevalence of foot diseases in outpatients attending the Institute of Dermatology, Bangkok, Thailand

Two thousand patients who visited the outpatient department at the Institute of Dermatology, Bangkok, were assessed for the presence of foot diseases by questionnaire and physical examination. Abnormalities were detected in 741 individuals (37.1%). Nonfungal conditions were more prevalent (31.4%), mainly consisting of eczema (254 cases, 12.7%) and psoriasis (176 cases, 8.8%). Fungal disease was observed in 119 cases (6.0%). There were 76 cases (3.8%) with tinea pedis and 33 cases (1.7%) with onychomycosis. The identified organisms causing tinea pedis were 57.9% nondermatophyte moulds, 36.8% dermatophytes, and 2.6%Candida spp. The corresponding organisms causing onychomycosis were 51.6% nondermatophyte moulds, 36.3% dermatophytes, and 6.0%Candida spp. Among nondermatophytes, Scytalidium dimidiatum was the leading pathogen while Trichophyton rubrum and T. mentagrophytes were the predominant dermatophytes identified. Diabetes mellitus, peripheral vascular disease and activities related to foot trauma were noted to be predisposing factors for onychomycosis. Footwear, particularly sandals and cut shoes, was the only factor relevant to individuals with tinea pedis (P < or = 0.05). In contrast with other published data on fungal foot infections, this study disclosed a higher prevalence of nondermatophyte organisms, predominantly S. dimidiatum, as the major cause of tinea pedis and onychomycosis. An increase in awareness is necessary to identify such cases, prevent misdiagnosis and initiate appropriate treatment.     

A clinicomycological study of fungal foot infections among Algerian military personnel

There have been few studies on fungal infection of the foot in military personnel. The aim of this study was to determine the prevalence and aetiological factors of superficial mycoses of the foot in military personnel attending the Department of Dermatology of the Army Central Hospital in Algiers, Algeria. A complete dermatological examination was performed in 650 male military personnel. Cultures of skin and nail specimens of the feet were performed for each participant. Fungal infection of the foot (including tinea pedis and Candida interdigital infection) was clinically diagnosed in 147, and confirmed in 119 by positive cultures, resulting in a total prevalence of 18.3%. When subjects were grouped according to military rank, fungal infection of the foot was prevalent in troop soldiers; when grouped according to years of service to the army, the infection was frequent in military recruits. The dermatophyte species Trichophyton rubrum (20.9%) and the yeast species Candida parapsilosis (18.7%) were shown to be the major causal agents isolated. Tinea pedis and Candida interdigital infection are the most prevalent (68%) superficial fungal infections among Algerian military personnel.     

Prevalence and risk factors for superficial fungal infections among Italian Navy Cadets

BACKGROUND: Limited studies on the prevalence and risk factors for superficial mycoses are available. OBJECTIVE: The aim of this paper was to evaluate the prevalence and risk factors for superficial mycoses (dermatophytes and Candida spp.) in a sample of young Italian people resident at a military school. METHODS: A total of 1,024 young cadets from the Italian Navy Petty Officers School in Taranto, including 975 (95.21%) males and 49 (4.79%) females, mean age 22.5 +/- 3.0 years (range 18-30), were consecutively examined by the same observer. A complete dermatological examination was performed on all the subjects, and skin scrapings for microscopy and fungal culture were obtained from suspected lesions. All the subjects completed a questionnaire providing information on sports practice, swimming-pool attendance, marching, wearing shower sandals, frequent use of 'gummed' shoes, history of severe traumas to the nails, presence of hyperhidrosis and history of superficial mycoses. The affected subjects were also asked if they were aware of their condition. Data were analysed by the Statistical Analysis System, version 8.0. The Fisher exact test and odds ratios were calculated. RESULTS: A total of 33 subjects (3.2%) were found to suffer from a mycologically confirmed fungal infection (3% by dermatophytes and 0.2% by Candida albicans): tinea pedis/Candida intertrigo of the feet was suspected in 126 (12.1%) subjects and confirmed in 30 (2.9%), including 28 cases of tinea pedis and 2 cases of Candida intertrigo; tinea cruris/Candida intertrigo of the groin was suspected in 28 (2.7%) subjects, but confirmed in only 1 case (0.1%); onychomycosis was suspected in 64 (6.1%) subjects and confirmed in 2 cases (0.2%). The organism most frequently responsible in tinea pedis was Trichophyton mentagrophytes var. interdigitale (82.1%). The same species (50%) and T. mentagrophytes var. mentagrophytes (50%) were associated with tinea unguium, Epidermophyton floccosum was the only species detected in tinea cruris. Non-dermatophytic filamentous fungi (Penicillium spp., Fusarium spp., Aspergillus spp. and Paecilomyces spp.), not considered pathogenic, were isolated in 48 samples. None of the risk factors analysed were significantly associated with fungal infection. Only 2 subjects out of the 33 people affected were aware of their condition. They both had tinea pedis. CONCLUSION: The prevalence of mycoses in sailors living in an Italian military school was lower than rates detected in other military populations. This may be due to the cadets' lifestyle and environmental conditions. The most frequent infection was tinea pedis, mainly caused by T. interdigitale. None of the investigated risk factors were significantly associated with the disease, and most of the affected individuals were not aware of their condition.     

Specific detection of Trichophyton rubrum and Trichophyton interdigitale based on loop‐mediated isothermal amplification (LAMP) from onychomycosis specimens

In diagnosing onychomycosis, diseases with similar features must be excluded by demonstrating the presence of fungal infection and identifying the fungal species. However, fungal culture of onychomycosis‐derived samples usually takes many weeks to yield species identification results, and is associated with a low successful culture rate. Loop‐mediated isothermal amplification (LAMP) is a highly sensitive and specific molecular biological method that can amplify DNA at a constant temperature, allowing for a simpler testing procedure, shorter detection time and less cost than conventional techniques including quantitative polymerase chain reaction. We have developed a new LAMP method specifically to detect Trichophyton rubrum (T. rubrum) and Trichophyton interdigitale (T. interdigitale), major causative dermatophytes for onychomycosis, and analyzed the correlation between LAMP results and those of the existing fungal culture method for the detection and identification of Trichophyton species from onychomycosis‐derived samples. The results showed that all 59 specimens in which T. rubrum or T. interdigitale was identified by fungal culture also tested positive by LAMP, giving a 100% positivity concordance rate between the two methods. Moreover, all 55 and four specimens in which T. rubrum and T. interdigitale were identified by fungal culture, respectively, also tested positive for each species by LAMP, again giving a 100% species‐identification concordance rate. The high correlation demonstrated between LAMP and fungal culture results in detection and identification of Trichophyton species from onychomycosis‐derived samples suggests high reliability of LAMP as a promising, alternative mycological detection and identification technique which can serve as an alternative to the fungal culture method.     

Factors influencing coexistence of toenail onychomycosis with tinea pedis and other dermatomycoses: a survey of 2761 patients

OBJECTIVE: To evaluate the prevalence and factors influencing the presence of concomitant dermatomycoses in patients with toenail onychomycosis. DESIGN: Prospective study based on a specially designed questionnaire completed by dermatologists. PATIENTS: A total of 2761 patients with toenail onychomycosis. MAIN OUTCOME MEASURES: The diagnosis of fungal skin infections was confirmed by direct microscopic examination or by culture. RESULTS: In 1181 patients (42.8%) with toenail onychomycosis, concomitant fungal skin infections were noted. Tinea pedis was the most common and was found in 933 patients (33.8%). Other concomitant fungal skin infections were fingernail onychomycosis (7.4%), tinea cruris (4.2%), tinea corporis (2.1%), tinea manuum (1.6%), and tinea capitis (0.5%). The presence of concomitant fungal skin infections depended on number of involved toenails; duration of onychomycosis; sex, age, and education level; area of residence; and type of isolated fungus. CONCLUSIONS: The coexistence of toenail onychomycosis with other types of fungal skin infections is a frequent phenomenon. It could be hypothesized that infected toenails may be a site from which the fungal infections could spread to other body areas. Effective therapy for onychomycosis might therefore be essential not only to treat the lesional toenails but also to prevent spreading the infection to other sites of the skin.     

The use of 40% urea cream in the treatment of moccasin tinea pedis

Moccasin tinea pedis is a chronic dermatophyte infection of the foot that is recalcitrant to topical antifungal therapy. Furthermore, most patients with moccasin tinea pedis also have onychomycosis, thus adding to the recalcitrant nature of the infection. The topical antifungals used as sole therapy are generally ineffective because the scale on the plantar surface impedes or limits the absorption of the antifungal agent. The aim of this study was to evaluate the efficacy of 40% urea cream as an adjunct to topical antifungals in the treatment of moccasin tinea pedis. Patients with untreated moccasin tinea pedis were selected from the general dermatology clinic. The diagnosis of moccasin tinea pedis was made clinically and confirmed with a potassium hydroxide test or a positive fungal culture. A total of 12 patients with moccasin tinea pedis were treated with 40% urea cream once daily and ciclopirox cream twice daily. Patients then were evaluated after 2 to 3 weeks of treatment for the presence of erythema, scaling, and pruritus. After 2 to 3 weeks, a 100% cure rate was achieved in the 12 patients treated with topical 40% urea cream and ciclopirox cream concomitantly.     

浅部真菌病2600例病原菌分析

目的了解昆明地区浅部致病真菌的分布情况。方法对本科2010年1月-2011年6月拟诊为浅部真菌病患者的临床标本再次进行镜检和分离培养及菌种鉴定,并对结果进行统计学分析。结果 7944份临床送验标本中,直接涂片镜检阳性率29.39%,培养阳性率19.70%,而镜检和(或)培养的阳性率为32.73%,显著高于单一的镜检或培养。上述3种方法的真菌检出率差异均有统计学意义(P均<0.005)。分离的1565株浅部致病真菌中,红色毛癣菌1088株(69.52%),马拉色菌216株(13.80%),须癣毛癣菌118株(7.54%)。镜检和(或)培养阳性的2600例浅部真菌病患者中,足癣803例(30.88%),甲真菌病424例(16.31%),股癣386例(14.85%),体癣364例(14.00%),花斑癣259例(9.96%),手癣194例(7.46%),马拉色菌毛囊炎83例(3.19%)和头癣46例(1.77%),同时患有手癣和足癣41例(1.58%)。结论镜检结合培养法的阳性率显著高于单一镜检或培养法,昆明地区浅部真菌的病种以足癣、甲真菌病、股癣较多见,浅部致病真菌以红色毛癣菌和马拉色菌为主。     

Characteristics of superficial fungal infections in the Riyadh region of Saudi Arabia

Background The prevalence and characteristics of superficial fungal infections (SFIs) vary with climatic conditions, lifestyle, and population migration patterns. This study was undertaken to determine the characteristics of SFIs amongst patients visiting the dermatology clinic of Riyadh Military Hospital, Riyadh, Saudi Arabia, during the period 2003–2005. Methods One hundred and nineteen patients with confirmed SFI (37 males and 82 females), aged between 5 months and 67 years, were included in this study. The diagnosis of SFI was based on clinical presentation confirmed by laboratory analysis. The type of mycotic pathogen and the site of infection were recorded as a function of age and sex. Results Onychomycosis (40.3%) was the most frequent infection, followed by tinea capitis (21.9%), tinea pedis (16%), tinea cruris (15.1%), and tinea corporis (6.7%). Tinea capitis was most prevalent (15.1%) in children (male to female ratio, 1 : 1.57), whereas tinea pedis was most common (11.8%) in adults (male to female ratio, 1 : 2.5). Trichophyton mentagrophytes and Microsporum canis were the most common dermatophytes responsible for tinea infections, and T. mentagrophytes, Candida spp., and Aspergillus spp. were mainly responsible for onychomycosis. Conclusion The prevalence of SFI was twofold greater in females than males. Children were most commonly affected by tinea capitis, whereas adults generally suffered from tinea pedis. The frequency of onychomycosis was nearly three times higher in adults. This study clearly shows that SFIs are of concern in both genders and in all age groups.     

Tinea pedis in Korean children

BACKGROUND: Tinea pedis is an infrequent disease in children before the age of puberty. There are few epidemiologic and clinical data regarding cases of tinea pedis observed in children. Materials and methods We prospectively collected all cases of tinea pedis in children diagnosed during the years 1995-1997. Only those showing a positive result with potassium hydroxide preparation were included in the study. We performed fungal cultures in Sabouraud's agar in all cases to document the etiologic fungi. The clinical characteristics were investigated. RESULTS: A total of 21 children, aged 3 months to 14 years, were included. Fifteen patients were boys and six were girls. The mean age was 7.1 years. All the children were otherwise healthy. Prior to the establishment of the diagnosis of tinea pedis, 17 patients (80.9%) were treated for eczema without improvement. The intertriginous type was most common (53.3%). The first or second toe-webs were the sites of predilection (32.3%). Eighteen children (86%) had a family history of tinea pedis and more than half of cases (52.4%) showed occurrence in the summer. The results of fungal cultures were positive in 13 patients (57%). Trichophyton rubrum was the most commonly isolated pathogen (69.2%). The other associated dermatoses were onychomycosis (33.3%), atopic dermatitis (14%), plantar warts (10%), and chronic urticaria (5%). Tinea pedis and onychomycosis cleared after treatment with topical antifungals with or without systemic antifungals in all cases. CONCLUSIONS: Tinea pedis in children can occur more frequently than suspected. Our study shows the strong association with a family history and the seasonal relationship with occurrence in summer in more than half of cases. We suggest that tinea pedis should be considered in the differential diagnosis of foot dermatitis in children.     

Ciclopirox gel in the treatment of patients with interdigital tinea pedis

Background Tinea pedis (athlete’s foot) is the most common fungal infection in the general population. Ciclopirox, a broad‐spectrum hydroxypyridone antifungal, has proven efficacy against the organisms commonly implicated in tinea pedis: Trichophyton rubrum, T. mentagrophytes and Epidermophyton floccosum. Objective Two multicenter, double‐blind, clinical studies compared the efficacy and safety of ciclopirox gel with that of its vehicle base in subjects with moderate interdigital tinea pedis with or without plantar involvement. Methods Three hundred and seventy‐four subjects were enrolled and randomized to one of two treatment groups: ciclopirox gel 0.77%, or ciclopirox gel vehicle, applied twice daily for 28 days, with a final visit up to day 50. The primary efficacy variable was Treatment Success defined as combined mycological cure and clinical improvement 75%. Secondary measures of effectiveness were Global Clinical Response, Sign and Symptom Severity Scores, Mycological Evaluation (KOH examination and final culture result), Mycological Cure (negative KOH and negative final culture results) and Treatment Cure (combined clinical and mycological cure). Results At endpoint (final post‐baseline visit), 60% of the ciclopirox subjects achieved treatment success compared to 6% of the vehicle subjects. At the same time point, 66% of ciclopirox subjects compared with 19% of vehicle subjects were either cleared or had excellent improvement. Pooled data showed that 85% of ciclopirox subjects were mycologically cured, compared to only 16% of vehicle subjects at day 43, 2 weeks post‐treatment. Conclusions Ciclopirox gel 0.77% applied twice daily for 4 weeks is an effective treatment of moderate interdigital tinea pedis due to T. rubrum, T. mentagrophytes and E. floccosum and is associated with a low incidence of minor adverse effects.     

儿童甲真菌病82例临床及病原菌分析

目的了解儿童甲真菌病的主要临床特征,危险因素及病原菌的种类和构成情况。方法对2003年3月～2006年12月本科门诊就诊的真菌直接镜检阳性的82例儿童甲真菌病患者(年龄≤18岁)进行流行病学调查及真菌的分离培养。结果儿童甲真菌病最常见的感染类型是远端侧缘甲下型,指甲感染者较趾甲感染者常见。手癣、足癣、甲外伤、长期穿不透气的鞋袜是儿童甲真菌病的危险因素。共分离出致病真菌64株,皮肤癣菌59株(92.19%),其中红色毛癣菌57株(89.06%);酵母菌5株(7.81%),白念珠菌最常见。结论儿童甲真菌病最常见的致病菌是红色毛癣菌,其次为白念珠菌。临床特征和危险因素的分析对于儿童甲真菌病的防治具有重要意义。     

Chronic dermatomycoses of the foot as risk factors for acute bacterial cellulitis of the leg: a case-control study

OBJECTIVE: To assess the role of foot dermatomycosis (tinea pedis and onychomycosis) and other candidate risk factors in the development of acute bacterial cellulitis of the leg. METHODS: A case-control study, including 243 patients (cases) with acute bacterial cellulitis of the leg and 467 controls, 2 per case, individually matched for gender, age (+/-5 years), hospital and admission date (+/-2 months). RESULTS: Overall, mycology-proven foot dermatomycosis was a significant risk factor for acute bacterial cellulitis (odds ratio, OR: 2.4; p < 0.001), as were tinea pedis interdigitalis (OR: 3.2; p < 0.001), tinea pedis plantaris (OR: 1.7; p = 0.005) and onychomycosis (OR: 2.2; p < 0.001) individually. Other risk factors included: disruption of the cutaneous barrier, history of bacterial cellulitis, chronic venous insufficiency and leg oedema. CONCLUSIONS: Tinea pedis and onychomycosis were found to be significant risk factors for acute bacterial cellulitis of the leg that are readily amenable to treatment with effective pharmacological therapy.     

Onychomycosis Caused by Scopulariopsis brevicaulis: Report of Two Cases

Onychomycosis is usually caused by dermatophytes, but some nondermatophytic molds and yeasts are also associated with invasion of nails. Scopulariopsis brevicaulis is a nondermatophytic mold found in soil as a saprophyte. We report two cases of onychomycosis caused by S. brevicaulis in a 48-year-old male and a 79-year-old female. The two patients presented with a typical distal and lateral subungual onychomycosis. Direct microscopic examination of the potassium hydroxide preparation revealed fungal elements. From toenail lesions of the patients, brown colonies with powdery surface, which are a characteristic of S. brevicaulis, were cultured on two Sabouraud''s dextrose agar plates. Three cultures taken from nail plates within a 2-week interval yielded similar findings. Numerous branched conidiophores with chains of rough walled, lemon-shaped conidia were observed in slide culture by light microscopy and scanning electron microscopy. The nucleotide sequences of the internal transcribed spacer for the two clinical isolates were identical to that of S. brevicaulis strain WM 04.498. To date, a total of 13 cases of S. brevicaulis onychomycosis including the two present cases have been reported in Korea. Mean age of the patients was 46.1 years, with a higher prevalence in males (69.2%). Toenail involvement was observed in all cases including a case involving both fingernail and toenail. The most frequent clinical presentation was distal and lateral subungual onychomycosis in 12 cases, while one case was proximal subungual onychomycosis.     

Epidemiologic surveillance of cutaneous fungal infection in the United States from 1999 to 2002

BACKGROUND: Cutaneous fungal infections are common in the United States, and causative organisms include dermatophytes, yeasts, and nondermatophyte molds. These organisms are in constant competition for their particular environmental niche, often resulting in the emergence of one or more predominant pathogens and displacement of other less competitive species. Changes in the incidence of fungal pathogens can be followed from laboratory culture results of infected cutaneous tissues over time. These data can be used to ascertain past and present trends in incidence, predict increases in antifungal resistance and the adequacy of our current pharmacologic repertoire, and provide insight into future developments. OBJECTIVE: This study identifies epidemiologic trends and the predominant organisms causing superficial fungal infections in the United States. METHODS: A total of 15,381 specimens were collected from clinically suspected tinea corporis, tinea cruris, tinea capitis, tinea faciei, tinea pedis, tinea manuum, and finger and toe onychomycosis from 1999 through 2002. Specimens were submitted to the Center for Medical Mycology in Cleveland, Ohio, for fungal culture and identification, and the incidence of each species was calculated. RESULTS: Dermatophytes remain the most commonly isolated fungal organisms except from clinically suspected finger onychomycosis, in which case Candida species comprise >70% of isolates. Trichophyton rubrum remains the most prevalent fungal pathogen, and increased incidence of this species was observed in finger and toe onychomycosis, tinea corporis and tinea cruris, tinea manuum, and tinea pedis. As the causal agent of tinea capitis, T tonsurans continues to increase in incidence, achieving near exclusionary proportions in the United States. CONCLUSION: Consideration of the current epidemiologic trends in the incidence of cutaneous fungal pathogens is of key importance to investigational efforts, diagnosis, and treatment.     

The efficacy of fractional carbon dioxide (CO2) laser combined with terbinafine hydrochloride 1% cream for the treatment of onychomycosis

Background: Although systemic and topical antifungal agents are widely used to treat onychomycosis, oral medications can cause adverse effects and the efficacy of topical agents is not satisfying. Currently, laser treatment has been studied for its efficacy in the treatment of onychomycosis. Our study was aimed to evaluate the efficacy of fractional carbon dioxide (CO₂) laser treatment combined with terbinafine cream for 6 months in the treatment of onychomycosis and to analyze the influencing factors. Methods: A total of 30 participants (124 nails) with clinical and mycological diagnosis of onychomycosis received fractional CO₂ laser treatment at 2-week interval combined with terbinafine cream once daily for 6 months. The clinical efficacy rate (CER) was assessed from the percentage of fully normal-appearing nails or nails with ≤5% abnormal appearance, and the mycological clearance rate (MCR) was assessed from the percentage of nails with negative fungal microscopy. Results: The CER was evaluated at 3 time points: at the end of treatment (58.9%), at 1 month after the last treatment (63.5%), and at 3 months after the last treatment (68.5%). The MCRs at 1 month and 3 months after the last treatment were 77.4 and 74.2%, respectively. The evaluation of influencing factors showed significantly higher CER (p < 0.05) in nails of participants with age <50 years, distal lateral subungual onychomycosis (DLSO), superficial white onychomycosis (SWO), nail thickness <2 mm, affected first-to-fourth finger/toenails, Trichophyton rubrum, and Trichophyton mentagrophytes. All participants experienced tolerable mild burning sensation during laser treatment, but there were no other adverse reactions reported. Conclusions: Fractional CO₂ laser treatment combined with terbinafine cream for 6 months was an effective and safe method for the treatment of onychomycosis. There were 5 factors that positively influenced the treatment outcome: age, clinical type of onychomycosis, nail thickness, involved nail, and species of fungus.