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R C Summerbell

Publications and source records attributed to R C Summerbell.

At least 37 records · Page 2Linked to original sources
PubMed2000

Novel cases of blastomycosis acquired in Toronto, Ontario.

Blastomycosis a potentially fatal fungal disease, is well known from defined areas of endemicity in Ontario, primarily in the northern part of the province. We present 2 unusual cases that appear to extend the area of endemicity into urban southern Ontario, specifically Toronto. Both patients presented to a dermatology clinic with skin lesions. Chest radiography, history and general physical evaluation indicated no disease at other body sites. Both cases appeared to represent "inoculation blastomycosis" connected with minor gardening injuries and a cat scratch respectively. Atypical dissemination could not be completely excluded in either case. Neither patient had travelled recently to a known area of high endemicity for blastomycosis, nor had the cat that was involved in one of the cases. Physicians must become aware that blastomycosis may mimic other diseases, including dermal infections, and may occur in patients whose travel histories would not normally suggest this infection.

Adult↗
PubMed2000

In vitro susceptibility of the seven Malassezia species to ketoconazole, voriconazole, itraconazole and terbinafine.

Fifty-five strains, either authentic or ex-type, of seven Malassezia species were investigated for in vitro susceptibility to various concentrations (0.03-64.0 microg/mL) of three azole drugs, ketoconazole, voriconazole and itraconazole, as well as the allylamine terbinafine, using the agar dilution method. All strains of the seven Malassezia species were susceptible to the three azole drugs at low concentrations. M. furfur, M. sympodialis, M. slooffiae, M. pachydermatis, M. globosa, M. obtusa and M. restricta were most sensitive to ketoconazole and itraconazole, with minimum inhibitory concentrations (MICs) ranging from < or = 0.03 to 0.125 microg/mL. The recently introduced antifungal, voriconazole, was also very effective, with MIC80 values < or = 0.03 microg/mL for 80% of strains. MICs of terbinafine against the seven Malassezia species ranged from </= 0.03 to 64.0 microg/mL. There were variations in susceptibility of the seven Malassezia species to ketoconazole, voriconazole, itraconazole and terbinafine. Strains of M. furfur, M. globosa and M. obtusa were more tolerant to terbinafine than the remaining Malassezia species; M. sympodialis was highly susceptible. M. furfur strains tested with terbinafine ranged from highly susceptible to relatively resistant. Correct identification of Malassezia species could facilitate selection of appropriate antifungal therapy.

Allylamine↗
PubMed2000

Once weekly fluconazole is effective in children in the treatment of tinea capitis: a prospective, multicentre study.

In an open, multicentre evaluation carried out in Brazil, Canada and South Africa we have demonstrated that fluconazole 8 mg kg-1 once weekly is effective in tinea capitis caused by Trichophyton and Microsporum species. There were 61 children, aged (mean +/- SE) 5.0 +/- 0.3 years; weight (mean +/- 5.6) 20.0 +/- 0.9 kg; 41 males, 20 females; one Asian, 57 Black, one Caucasian and two Hispanic. The organisms were Trichophyton violaceum (33 patients), T. tonsurans (11) and Microsporum canis (17). The extent of tinea capitis at pretherapy was: mild (18 patients), moderate (30) and severe (13). Patients with tinea capitis due to Trichophyton species were initially treated for 8 weeks with an extra 4 weeks of fluconazole if clinically indicated. All 44 patients with tinea capitis due to Trichophyton species were completely cured (clinically and mycologically) when evaluated 8 weeks after completion of active treatment, following 8 weeks of once weekly dosing in 35 patients and 12 weeks of once weekly dosing in nine patients. In Microsporum canis tinea capitis, an extra 4 weeks was administered at week 12 in patients where it was clinically indicated at the time. Sixteen of 17 patients with M. canis tinea capitis were completely cured (clinically and mycologically) when evaluated 8 weeks following the end of treatment when given for 8, 12 and 16 weeks in 12, one and three patients, respectively. Overall, complete cure (clinical and mycological) occurred in 60 of 61 patients at follow-up 8 weeks from the end of therapy. The duration of once weekly fluconazole in the 60 patients was 8 weeks (47 patients), 12 weeks (10 patients) and 16 weeks (three patients), respectively. Clinical adverse effects consisted of a mild, reversible gastrointestinal complaint in three (4.9%) of 61 children. A laboratory abnormality with elevated liver function tests was observed in one (5.9%) of 17 patients; this was asymptomatic, and reversible. No patient discontinued therapy. The data suggest that once weekly fluconazole dosing is effective, safe and associated with high compliance when used to treat tinea capitis.

Antifungal Agents↗
PubMed2000

Epidemiology and prevalence of onychomycosis in HIV-positive individuals.

BACKGROUND: Patients who are human immunodeficiency virus (HIV) positive are predisposed to the development of infections including tinea pedis and onychomycosis. While smaller studies have been reported, there has been no large study evaluating the prevalence of onychomycosis in HIV-positive individuals, or comparing the development of onychomycosis in a typical temperate area with that in a typical tropical area. METHODS: HIV-positive individuals were evaluated at five clinics: four in Ontario, Canada and one in Sao Paulo, Brazil. The subjects were asked questions to determine the epidemiology of onychomycosis in HIV-positive individuals. The feet were examined and nail material was obtained for mycologic examination to determine the causative organism of onychomycosis. RESULTS: A total of 500 subjects were examined (415 men and 85 women; age (mean +/- SE), 39 +/- 0.4 years; 400 Canadian, 100 Brazilian). The racial origins of the Canadian patients were: Caucasian, 83.8%; Asian, 4.3%; African-American, 8.1%; Hispanic, 3.3%; American Indian, 0.3%. The Brazilian origins were: Caucasian, 68.7%; African, 18.1%; mixed race, 13.3%. Abnormal appearing nails and mycologic evidence of onychomycosis were present in 200 (40.0%) and 116 (23.2%), respectively, of 500 subjects. The prevalence of onychomycosis in the Canadian and Brazilian samples was 24.0% (96 of 400) and 20.0% (20 of 100), respectively. The projected prevalence of onychomycosis in HIV-positive individuals in Canada was 19.9% (95% CI: 16.0-23.9%) after taking into account the age and sex distribution of HIV-positive individuals in the population. When nails appeared clinically abnormal, the prevalence of onychomycosis was 50.5% (Canada, 51.3%; Brazil, 45.5%). For comparison, published data indicate that the prevalence of onychomycosis in immunocompetent individuals living in Canada is 6.9%. The clinical presentation of onychomycosis for the whole sample (n=500) was: distal and lateral subungual onychomycosis (DLSO), 20.0%; white superficial onychomycosis (WSO), 3.6%; proximal subungual onychomycosis (PSO), 1.8% (Canadian and Brazilian samples: DLSO 21.2% vs. 15.0%, WSO 3.3% vs. 5.0%, and PSO 1.5% vs. 3.0%). The distribution of the causative fungal organisms was: dermatophytes: Candida species: nondermatophyte molds, 73:2:2 (Canadian and Brazilian samples: dermatophytes 95.5% vs. 90.9%, Candida species 3.0% vs. 0%, and nondermatophyte molds 1.5% vs. 9.0%). The use of protease inhibitors, reverse transcriptase inhibitors, or oral antifungal agents did not make a significant difference in the prevalence of onychomycosis for both the Canadian and Brazilian groups. Patients with onychomycosis were aware of their abnormal appearing nails (chi2(1)=69.7, P<0.001), embarrassed by the appearance of their nails (chi2(1)=29.7, P<0.001), and took measures to hide their nails from other individuals. A higher proportion of individuals with onychomycosis experienced discomfort compared with those without the disease (chi2(1)=9.0, P=0.003). Also, individuals who experienced pain in the nail unit were more likely to have onychomycosis (risk odds ratio (ROR), 2.2; 95% CI: 1.0-4.7, P=0.05). CONCLUSIONS: The prevalence of onychomycosis in HIV-positive individuals in the sample of 500 patients was 23.2%. In the Canadian (n=400) and Brazilian (n=100) samples, the corresponding figures were 24% and 20%, respectively, with the predominant causative organisms being dermatophytes. The projected prevalence of onychomycosis in HIV-positive Canadians is 19.9%. Predisposing factors include a CD4 count of approximately 370, a positive family history of onychomycosis, a history of tinea pedis, and walking barefoot around pools. Onychomycosis can be symptomatic, a source of embarrassment, and a potential cause of morbidity.

Adolescent↗
PubMed2000

The epidemiology of onychomycosis: possible role of smoking and peripheral arterial disease.

BACKGROUND: Onychomycosis is a relatively common condition the aetiology of which appears to be multifactorial, with both genetic and acquired factors being responsible. In our clinical practice we have observed that smokers and individuals with peripheral arterial disease may have an increased prevalence of onychomycosis compared to normal individuals. PATIENTS AND METHODS: Patients attending a vascular clinic in a hospital were asked about a history of smoking and peripheral arterial disease. The lower extremity was assessed for peripheral arterial disease. Material was obtained from toenails for mycological evaluation. RESULTS: Two hundred and fifty-four patients (male 146, female 108; age, mean +/- standard error, 66.6 +/- 0.8 years) were enrolled. Abnormal-appearing nails and onychomycosis were present in 49.2% and 22.4% of patients, respectively. Factors associated with onychomycosis included, increasing age (risk odds ratio [ROR] 1.05, P = 0.002), male gender (ROR 1.7, P = 0.09), smoking (packs per day) (ROR 1.9, P = 0.02) and peripheral arterial disease (ROR 4.8, P = 0.02). CONCLUSIONS: The factors predisposing to the development of onychomycosis are multifactorial. Both smoking (number of packs of cigarettes consumed per day) and peripheral arterial disease are independent predictors of onychomycosis. Awareness of these factors may help in the prevention of onychomycosis and the optimal management of this disease.

Age Distribution↗
PubMed2000

Detection of xanthomegnin in epidermal materials infected with Trichophyton rubrum.

Xanthomegnin, a mutagenic mycotoxin best known as an agent of nephropathy and death in farm animals exposed to food-borne Penicillium and Aspergillus fungi, was first isolated about 35 y ago as a diffusing pigment from cultures of the dermatophyte, Trichophyton megninii. This study investigates the production of xanthomegnin by the most common dermatophytic species, Trichophyton rubrum, both in dermatologic nail specimens and in culture. In view of the labile nature of xanthomegnin, a chromatographic procedure was developed to allow high-performance liquid chromatography analysis within 1 h of sample extraction. In cultures, Tricho- phyton rubrum produced xanthomegnin as a major pigment that appears to give the culture its characteristic red colony reverse. Xanthomegnin was also repeatedly extracted from human nail and skin material infected by Trichophyton rubrum. The level of xanthomegnin present, however, varied among the clinical samples studied. Xanthomegnin was not detected in uninfected nails. These results show that patients with Trichophyton rubrum infections may be exposed to xanthomegnin, although the consequences of such an exposure are not currently known.

Chromatography, High Pressure Liquid↗
PubMed2000

Prevalence and epidemiology of onychomycosis in patients visiting physicians' offices: a multicenter canadian survey of 15,000 patients.

A prospective, multicenter study to determine the epidemiology of onychomycosis was performed in the offices of 3 dermatologists and 1 family physician in Ontario, Canada. In the sample of 15,000 patients, abnormal-appearing nails were observed in 2505 persons (16. 7%). There were 1199 patients (8%) with toenail or fingernail onychomycosis confirmed on mycologic examination, with 1137 patients (7.6%) who had only pedal onychomycosis, 40 patients with toenail and fingernail onychomycosis (0.27%), and 22 patients (0.15%) with only fingernail onychomycosis. The condition was more common in male patients (P <.0001) and older persons (P <.0001). The ratio of onychomycosis in toenails/fingernails was 19:1. When onychomycosis was present in toenails, the ratio of distal/lateral subungual onychomycosis (DLSO) to white superficial onychomycosis to proximal subungual onychomycosis was 360:59:1. The extent of DLSO in toenails was mild (< or =25% nail involvement), moderate (26%-74% disease), and severe (> or =75% nail involvement) in 27.6%, 39.9%, and 32.5% of patients, respectively. After adjusting for the age and sex distribution of the general population, the projected rate of onychomycosis in Canada is 6.5% (95% confidence interval [CI], 6. 1%-6.9%). The organisms causing toenail onychomycosis were 90.5% dermatophyte, 7.8% nondermatophyte molds, and 1.7% Candida spp. The corresponding organisms causing fingernail onychomycosis were 70.8%, 0%, and 29.2%, respectively. In a large sample of 15,000 patients, abnormal-appearing nails were present in 17% of the sample with mycologic evidence of toenail or fingernail onychomycosis in 8%. The projected prevalence of onychomycosis in Canada is 6.5% (95% CI, 6. 1%-6.9%).

Adolescent↗
PubMed2000

Tinea capitis.

Tinea capitis is a common dermatophyte infection of the scalp in children. Dermatophytes are classified into three genera; tinea capitis is caused predominantly by Trichophyton or Microsporum species. On the basis of host preference and natural habitat, dermatophytes are also classified as anthropophilic, geophilic and zoophilic. The etiological agents of tinea capitis usually fall in the first and last categories. In North America, tinea capitis is now predominantly due to Trichophyton tonsurans. During the past 100 years the most common North American organism for tinea capitis was initially Microsporum canis followed later by M. audouinii. In other parts of the world the epidemiology varies. Tinea capitis is generally observed in children over the age of 6 years and before puberty, with African Americans being the most affected group. Clinical presentations are seborrheic-like scale, 'black dot' pattern, inflammatory tinea capitis with kerion and tiny pustules in the scalp. The clinical diagnosis should be confirmed by mycological examination. Wood's light examination was of value in diagnosing tinea capitis due to M. canis and M. audouinii; however, it is not helpful in T. tonsurans tinea capitis. Asymptomatic carriers may be a significant reservoir of infection and spread of spores may also involve inanimate objects. Carriers may benefit from shampooing their hair. Treatment of tinea capitis requires an oral antifungal agent. The data from the use of terbinafine, itraconazole and fluconazole are promising and suggest that these agents have an efficacy similar to griseofulvin while shortening the duration of therapy. Both griseofulvin and the newer antimycotics have a favorable adverse-effect profile and are associated with high compliance.

Antifungal Agents↗
PubMed2000

Molecular differentiation of seven Malassezia species.

A system based on PCR and restriction endonuclease analysis was developed to distinguish the seven currently recognized Malassezia species. Seventy-eight strains, including authentic culture collection strains and routine clinical isolates, were investigated for variation in the ribosomal DNA repeat units. Two genomic regions, namely, the large subunit of the ribosomal gene and the internal transcribed spacer (ITS) region, were amplified by PCR, and products were digested with restriction endonucleases. The patterns generated were useful in identification of five out of seven Malassezia species. M. sympodialis was readily distinguishable in that its ITS region yielded a 700-bp amplified fragment, whereas the other six species yielded an 800-bp fragment. M. globosa and M. restricta were very similar in the regions studied and could be distinguished only by performing a hot start-touchdown PCR on primers for the beta-tubulin gene. Primers based on the conserved areas of the Candida cylindracea lipase gene, which were used in an attempt to amplify Malassezia lipases, yielded an amplification product after annealing at 55 degrees C only with M. pachydermatis. This specific amplification may facilitate the rapid identification of this organism.

Animals↗
PubMed1999

Combined distal and lateral subungual and white superficial onychomycosis in the toenails.

BACKGROUND: The 5 main types of onychomycosis are distal and lateral subungual onychomycosis (DLSO), white superficial onychomycosis (WSO), proximal subungual onychomycosis (PSO), Candida onychomycosis, and total dystrophic onychomycosis (TDO) (primary or secondary type). In the literature there is infrequent discussion about 2 types of onychomycosis present in the toenails of the same individual. OBJECTIVE: We attempted to determine the prevalence and etiologic organisms of DLSO and WSO occurring in the same individual. METHODS: We surveyed 4411 subjects presenting to dermatology offices for causes other than the management of onychomycosis. In each patient the toenails were examined. If they appeared abnormal, nail material was obtained for mycologic evaluation; partitioned sampling was performed when more than one type of onychomycosis was present. RESULTS: In our series, 39 (0.9%) of 4411 patients had the combination DLSO and WSO, compared with 417 (9.4%) and 111 (2.5%) who had DLSO and WSO, respectively. After controlling for age and sex in the general population, the projected prevalence rates of DLSO, WSO, and combined DLSO and WSO in the province of Ontario, Canada were 7.1%, 1.5%, and 0.5%, respectively. The combination of DLSO and WSO in the toenails of an individual occurred more frequently than that predicted by chance alone (P <.0001). Nine (0. 2%) of 4411 subjects had DLSO and WSO on the same nail. In 23 (59%) of 39 subjects both the DLSO and WSO were associated with Trichophyton mentagrophytes. In the remaining 16 subjects other organisms cultured were T rubrum, Acremonium spp, Aspergillus spp, Fusarium oxysporum, and Onychocola canadensis. In 33 (84.6%) of 39 subjects with the combination of DLSO and WSO on the toenails, the same fungal organism was associated with both the DLSO and WSO. CONCLUSION: When both DLSO and WSO are concurrently present in the toenails of an individual, partitioned sampling (ie, sampling for each of the two types of onychomycosis) may provide us with a better understanding of the different organisms associated with the onychomycosis and the relationship between the two types of onychomycosis.

Aged↗
PubMed1999

Intermittent short duration therapy with fluconazole is effective for tinea capitis.

We have demonstrated in an open multicentre investigation that oral fluconazole 6 mg/kg daily for 2 weeks, followed, if clinically indicated four weeks from the start of therapy, by an extra week of treatment at the same dosage, may be effective and safe in the treatment of tinea capitis. Of a total of 48 patients, there were 42 evaluable children < 18 years old (19 boys, 23 girls; mean age 6.2 years, range 1.5-16). The causative organisms were Trichophyton tonsurans (38 subjects) and T. violaceum (four). In the 42 evaluable patients, a 2-week course of fluconazole was administered in 21, with the remainder requiring 1 additional week of therapy. At follow-up 12 weeks from the start of therapy, mycological and clinical cure was recorded in 37 of the 42 evaluable patients (88.1%, 95% confidence interval 83.1-93.1%). The treatment was well tolerated, with no clinical adverse effects. This regimen appears to be effective and safe, and is associated with high compliance. The preliminary results of the investigation need to be evaluated in a larger sample of patients, and in tinea capitis caused by zoophilic species.

Adolescent↗
PubMed1999

Multilocus genotypes and DNA fingerprints Do not predict variation in azole resistance among clinical isolates of Candida albicans.

If variation in azole resistance is due to inherent differences in strains of Candida albicans, as a predominantly clonal organism, then correlation between multilocus genotypes and drug resistance would be expected. A sample of 81 clinical isolates from patients infected with human immunodeficiency virus in Toronto, Canada, plus 3 reference isolates were genotyped at 16 loci, distributed on all linkage groups, by means of oligonucleotide hybridizations specific for each of the alleles at each locus. These multilocus genotypes were significantly correlated with DNA fingerprints obtained with the species-specific probe 27A, indicating widespread linkage disequilibrium in the genome. There were 64 multilocus diploid genotypes and 77 DNA fingerprint types delineated in this sample. Neither the multilocus genotyping nor DNA fingerprinting alone identified all of the 81 types identified by the combination of these two methods. Multilocus genotypes were not predictive of fluconazole resistance, suggesting that resistance is gained or lost too quickly to be predicted by linkage with neutral markers.

Antifungal Agents↗
PubMed1999

rRNA gene internal transcribed spacer 1 and 2 sequences of asexual, anthropophilic dermatophytes related to Trichophyton rubrum.

The ribosomal region spanning the two internal transcribed spacer (ITS) regions and the 5.8S ribosomal DNA region was sequenced for asexual, anthropophilic dermatophyte species with morphological similarity to Trichophyton rubrum, as well as for members of the three previously delineated, related major clades in the T. mentagrophytes complex. Representative isolates of T. raubitschekii, T. fischeri, and T. kanei were found to have ITS sequences identical to that of T. rubrum. The ITS sequences of T. soudanense and T. megninii differed from that of T. rubrum by only a small number of base pairs. Their continued status as species, however, appears to meet criteria outlined in the population genetics-based cohesion species concept of A. R. Templeton. The ITS sequence of T. tonsurans differed from that of the biologically distinct T. equinum by only 1 bp, while the ITS sequence of the recently described species T. krajdenii had a sequence identical to that of T. mentagrophytes isolates related to the teleomorph Arthroderma vanbreuseghemii.

Arthrodermataceae↗
PubMed1999

Onychomycosis: predisposed populations and some predictors of suboptimal response to oral antifungal agents.

The population groups predisposed to onychomycosis and factors associated with a poor response to antifungal therapy may be subdivided into (a) genetic, (b) environmental, (c) systemic conditions, (d) local nail characteristics, and (e) other miscellaneous items. By paying attention to the scenarios that may lead to a suboptimal response to the therapy and a higher probability of relapse of the onychomycosis, it may be possible to improve the overall cost-effectiveness of treatments for onychomycosis. Besides attempting to achieve a cure when treating onychomycosis it is important to take steps to prevent reinfection with fungal organisms.

Antifungal Agents↗
PubMed1998

Treatment of tinea capitis with itraconazole capsule pulse therapy.

BACKGROUND: The number of newly diagnosed cases of tinea capitis in children appears to be on the rise, particularly in urban centers. OBJECTIVE: The purpose of this study was to assess the effectiveness, safety, and compliance of itraconazole pulse therapy for tinea capitis. METHODS: Fifty subjects (48 children [less than 18 years of age] and 2 adults) with tinea capitis were treated with pulse itraconazole in a multicenter evaluation. Each pulse lasted 1 week, with 2 weeks between the first two pulses and 3 weeks between the second and third pulses. The decision to administer a second or third pulse was determined by the response of the subject at the time that the next pulse was due. During the 1-week pulse of active therapy, itraconazole (5 mg/kg/day) was dosed as follows: more than 40 kg, 200 mg per day (two capsules per day); 20 to 40 kg, 100 mg per day (one capsule per day); and 10 to 19 kg, 50 mg per day (one half of a capsule per day). The duration of the study was 12 weeks with mycologic evaluation at this time. Subjects who were classified as treatment failures at 12 weeks after the start of therapy were given the option of receiving an additional 1-week pulse of active therapy, with 3 weeks between successive pulses. RESULTS: The causative organisms were Trichophyton tonsurans (41 subjects), T violaceum (7), T. soudanense (1), and T rubrum (1). Thirteen subjects were lost to follow-up, with 37 subjects (35 children and 2 adults) available for evaluation 12 weeks after the start of therapy. At this time, cure (clinical and mycologic) was observed in 30 (81%) of 37 subjects. When the tinea capitis was mild, cure was obtained after one pulse in two subjects and after two pulses in five subjects. With tinea capitis of moderate extent, complete cure was obtained after one pulse in one subject, two pulses in eight subjects, and after three pulses in seven subjects. When tinea capitis was severe, two and three pulses produced complete cure in one and six subjects, respectively. Of the seven subjects whose conditions failed to respond (three subjects with moderate disease and four subjects with severe disease), five subjects chose to receive extra itraconazole. Clinical and mycologic cure was observed after four pulses in four subjects and after five pulses in one subject. There were no associated clinical adverse effects with itraconazole therapy. CONCLUSION: With tinea capitis, itraconazole pulse therapy is effective and safe and is associated with high compliance. The pulse regimen enables the duration of treatment to be individualized, according to the extent of disease and its rate of resolution.

Antifungal Agents↗
PubMed1998

Onychomycosis associated with Onychocola canadensis: ten case reports and a review of the literature.

BACKGROUND: Onychocola canadensis is a nondermatophyte mold associated with onychomycosis particularly in temperate climates (eg, Canada, New Zealand, and France). The slow growth rate of O canadensis and lack of resemblance to any other known nail-infecting fungus may have delayed its discovery. We are aware of 23 mycologically confirmed cases of O canadensis in the literature. OBJECTIVE: We describe 10 previously unreported Canadian patients, specimens from whom grew O canadensis. We also review the literature on infections associated with this organism. METHODS: Cases of O canadensis onychomycosis were diagnosed on the basis of (1) the finding of compatible filaments on direct microscopy of nail and (2) consistent culture from repeated specimens. All patients from whom O canadensis was isolated were followed up, but those in whom outgrowth was not consistent were not accepted as having "authentic" infections. RESULTS: In 10 patients O canadensis was found to be associated with distal lateral subungual onychomycosis (6 patients), white superficial onychomycosis (1 patient), and as an insignificant contaminant in the nails of 3 patients. Less commonly the organism may cause tinea manuum or tinea pedis interdigitalis. O canadensis appears to be more frequent in the elderly, especially females. It is not unusual for a patient with onychomycosis caused by O canadensis to be a gardener or farmer, suggesting that the infectious inoculum may originate from the soil. The optimal therapy for onychomycosis caused by this organism remains unclear. CONCLUSION: O canadensis may be the etiologic agent of distal and lateral subungual or white superficial onychomycosis; however, it may sometimes be present in an abnormal-appearing nail as an insignificant finding, not acting as a pathogen.

Aged↗