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.

Onychomycosis is a fungal nail infection caused by dermatophytes, nondermatophyte molds, and yeasts. This difficult‐to‐treat chronic infection has a tendency to relapse despite treatment. This paper aims to offer a global perspective on onychomycosis management from expert physicians from around the world. Overall, the majority of experts surveyed used systemic, topical, and combination treatments approved in their countries and monitored patients based on the product insert or government recommendations. Although the basics of treating onychomycosis were similar between countries, slight differences in onychomycosis management between countries were found. These differences were mainly due to different approaches to adjunctive therapy, rating the severity of disease and use of prophylaxis treatment. A global perspective on the treatment of onychomycosis provides a framework of success for the committed clinician with appreciation of how onychomycosis is managed worldwide.

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.

Onychomycosis is estimated at a prevalence of 10% worldwide with the infecting organism most commonly Trichophyton rubrum (T. rubrum). Traditional culture identification of causative organisms has inherent risks of overestimating dermatophytes, like T. rubrum, by inhibiting the growth of possible nondermatophyte mould (NDM) environmental contaminants which could be causative agents. Recently, molecular methods have revealed that a proportion of onychomycosis cases in North America may be caused by mixed infections of T. rubrum as an agent co-infecting with one or more NDM. Determining the global burden of mixed infections is a necessary step to evaluating the best therapies for this difficult-to-treat disease. To determine the prevalence of mixed infections in a global population, nail samples from onychomycosis patients in Brazil, Canada, and Israel (n = 216) were analyzed by molecular methods for the presence of dermatophytes and five NDMs. If an NDM was detected, repeat sampling was performed to confirm the NDM. T. rubrum was detected in 98% (211/216) of infections with 39% mixed (84/216). The infection type was more likely to be mixed in samples from Brazil, but more likely to be a dermatophyte in samples from Canada and Israel (Χ 2 = 16.92, df = 2, P<0.001). The most common cause of onychomycosis was T. rubrum. In all countries (Brazil, Canada and Israel combined) the prevalence of dermatophyte (Χ 2 = 211.15, df = 3, P<0.001) and mixed (dermatophyte and NDM; Χ 2 = 166.38, df = 3, P<0.001) infection increased with patient age. Our data suggest that mixed infection onychomycosis is more prevalent than previously reported with the aging population being at increased risk for mixed infections.

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.