Tinea capitis in south-east London--a new pattern of infection with public health implications.

Recent observations on tinea capitis cases in London suggest that there has been a change in the pattern of infection with a recent and significant rise in the incidence of infections due to anthropophilic fungi. The purpose of this study was to investigate the prevalence and identity of tinea capitis in schools in south-east London and factors which might affect the spread of infection. This was achieved by carrying out a survey of all children, with parental consent for scalp examination, in 14 nursery, infant or junior schools in Lambeth. In addition, the accuracy of clinical diagnosis was compared with mycological findings. There were 1057 children from 4 to 14 years of age in the study. The infection rate in different schools ranged from 0 to 12% with a mean of 2.5%. A further 4.9% of children were scalp carriers of dermatophytes (range in classes 0-47%). A striking feature was that all infections were caused by anthropophilic fungi, mainly Trichophyton tonsurans or Microsporum rivalieri, and there was a correlation between the presence of two or more carriers within a class and the infection in the other children. There was a poor correlation between ability of trained observers to predict infection on clinical grounds and mycological results. This investigation shows variable but significant levels of scalp ringworm in schools and that the dominant organisms are anthropophilic. It provides support for the observation that there has been a shift in the pattern of tinea capitis in London and, possibly, other U.K. centres, with a trend towards more infections transmissible among children, with T, tonsurans being the commonest organism. The implications for control, which involve screening in schools, where appropriate, and guidance to general practitioners on treatment, are discussed.

Fungal aerobiology: how, when and where?

While there is undoubted risk of infection in certain hospitalized patients following exposure to inhaled spores of fungi such as Aspergillus, the actual risk appears to vary with the underlying condition. Secondly, the degree of exposure assessed by colony forming units (cfu) per unit of ambient air is not predictable. Thirdly, severely immunocompromised patients, mainly the severely neutropenic group, are at risk from infection at very low levels of ambient Aspergillus spores. From this it can be argued that the latter group requires some form of environmental protection or prophylaxis whatever the circumstances. At present the best approach is the use of highly filtered ward areas e.g. laminar air flow rooms. Monitoring spore loads is unlikely to affect management per se provided that the ventilation systems are regularly and effectively serviced. In non-neutropenic patients the risk of infection due to colonization, for instance of the paranasal sinuses, prior to hospital admission may be as great as that occurring due to exposure within hospital and filtration of air has a lesser value. The situation may alter, though, even in these patients if the risk level is increased by a building programme in the vicinity of ward areas.

A comparison of 2 weeks of terbinafine 250 mg/day with 4 weeks of itraconazole 100 mg/day in plantar-type tinea pedis.

This double-blind, parallel group study compared a 2-week course of terbinafine 250 mg/day with a 4-week course of itraconazole 100 mg/day. A total of 190 patients were enrolled, of whom 129 were evaluable for efficacy. At week 8, 69% of patients treated with terbinafine were classified as effectively treated (mycological cure, and clinical assessment total score < or = 2) vs. 67% in the itraconazole group. At week 16, however, the rating for effective treatment increased to 71% of the terbinafine group, but decreased to 55% of the itraconazole group. This difference was of borderline statistical significance (P = 0.06). The results of this study demonstrate that both drugs can be used safely, and that 2 weeks' treatment with terbinafine 250 mg daily is as effective as 4 weeks' treatment with itraconazole 100 mg daily, but with fewer long-term relapses.

Mycotic keratitis: susceptibility to antiseptic agents.

Oculomycosis is a severe problem in most developing countries. Specific antifungal agents are often unavailable, and are expensive. The use of antiseptic agents was therefore explored. Fungal isolates from patients in India and Ghana were tested against chlorhexidine, povidone iodine, propamidine, and polyhexamethylenebiguanide, and compared with econazole by placing the drugs in wells made in Sabouraud's agar plates seeded with the test organism. Fungal sensitivity testing is a contentious area but this method is simple and cheap. Chlorhexidine showed a good dose related response, povidone iodine showed a good response at all concentrations and econazole was the most effective in vitro. A small pilot study was conducted in India to assess clinical efficacy for fungal corneal ulcers. Both chlorhexidine and econazole proved effective but povidone iodine was ineffective. We suggest that chlorhexidine may be a useful first line agent for fungal keratitis when other antifungals are not available.

Relevance of broad-spectrum and fungicidal activity of antifungals in the treatment of dermatomycoses.

The in vitro fungistatic and fungicidal activities of terbinafine, amorolfine and itraconazole against dermatophytes were compared. All three compounds showed very good activity against all dermatophyte species tested, but only terbinafine and amorolfine exhibited primary fungicidal activity. These two compounds were also active in vitro against other filamentous fungi which cause onychomycoses, such as Scytalidium and Scopulariopsis species.

Environmental sampling for aspergilli during building construction on a hospital site.

During the course of extensive building activity at Guy's Hospital, London, air sampling was carried out weekly, for one year, to monitor the frequency of spores of Aspergillus spp. in both the hospital grounds and a number of defined ward areas. Nasal swabs were taken from patients on a selected ward to assess the nasal carriage of Aspergillus. The weather conditions were monitored at the time of sampling. The predominant species was Aspergillus fumigatus which occurred at a low frequency throughout the year, with little evidence of seasonal variation bar a peak in March. Few differences were found between internal and external spore counts. Localized building activity in a ward area and a laboratory area did not result in higher internal levels. Six percent of the nasal swabs were positive for A. fumigatus, though none of these patients became infected.

Oral yeast flora of a population in an area of Tanzania bordering an AIDS endemic zone.

Mouth swabs from 1,288 individuals in the North Mara region of Tanzania were cultured for yeasts. Subjects were randomly selected from rural and urban areas, and a group of food handlers were also studied. Yeasts were cultured from 407 (31.6%) and Candida albicans from 141 (10.9%) subjects. A wide variety of other yeast species were also identified.

PIP: Between May-October 1989, health personnel took mouth swabs from 875 15-55 year old male and female adults from rural Luo Imbo division of Tarime district, 145 similar individuals from the town of Tarime, and 268 food handlers from Tarime and other neighboring towns in the North Mara region of Tanzania to determine the prevalence of oral yeast flora in areas near an AIDS endemic zone. Laboratory personnel at the Shirati Hospital in Shirati isolated yeasts in 31.6% of the cases with most cases having Candida albicans (10.9%) followed by Saccharomyces cerevisiae (7.4%) and Trichosporon capitatum (6.5%). They were able to identify at least 23 other yeasts among the study group. Food handlers had the highest carriage rate (36.4%) then rural dwellers (32.5%) and urban dwellers (24.8%). C. albicans was present more often in the food handlers (17.5%) than either the rural or urban dwellers (9.5%) and 6.9% respectively). Thus the researchers suggested that the already occurring medical surveillance activities of food handlers should also monitor Candida infection. S. cerevisiae (used in food and drink fermentation processes) was also more prevalent in food handlers (10.8%) than the other 2 groups (6.3% and 7.6% respectively). On the other hand, laboratory staff isolated T. capitatum more often from rural dwellers (8.6%) than urban dwellers (2.1%) and food handlers (2.6%). In a study in Zaire, S. cerevisiae was the predominant oral yeast in AIDS patients. 9 (0.7%) subjects had T. beigelii, 1 of whom carried HIV-1. which has been associated with invasive infections in immunocompromised patients. Ongoing seroepidemiological studies in Tanzania are looking at any associations between subclinical C. albicans and other yeast infections, HIV-1 infection, and the development of AIDS.

A comparative study of terbinafine versus griseofulvin in 'dry-type' dermatophyte infections.

We conducted a double-blind comparative study of terbinafine, 250 mg twice daily, versus griseofulvin, 500 mg twice daily, for 6 weeks in chronic dermatophyte infections of the feet or hands. All but three patients (total 31) had Trichophyton rubrum infection. At 12-week follow-up, 100% of the terbinafine-treated group were free from infection compared with 45% of those treated with griseofulvin. Therapy in 75% of the terbinafine-treated group and in 35% of those given griseofulvin was rated as effective overall at long-term follow-up, although these differences were not statistically significant. Six months after treatment all nine patients whose skin had cleared with terbinafine therapy remained in remission versus only one of seven patients treated with griseofulvin. None of the patients in either group experienced serious adverse effects.

Sphaeropsis subglobosa keratomycosis--first reported case.

Recurrent keratomycosis is reported due to the coelomycete Sphaeropsis subglobosa, which has not been recognised previously as a human pathogen. Infection followed corneal injury by a frayed bamboo cane with implantation of its splinters. Initial successful therapy with 2% clotrimazole topically, to which it was sensitive, was followed by recurrent infection after 39 months, initially a keratitis but progressing to an endophthalmitis. Penetrating keratoplasty was necessary to eradicate the infection. Further isolation of the fungus showed that it had not developed resistance to clotrimazole but had survived dormant, deep in the corneal stroma. S. subglobosa should be considered in bamboo-associated and horticultural injuries.

Itraconazole in the management of chronic dermatophytosis.

Fifty-five patients with griseofulvin-unresponsive dermatophytosis caused by Trichophyton rubrum were treated with itraconazole. They had either tinea corporis or "dry type" infections of the palms, soles, or nails. The following sites were affected: trunk (12 infections), soles (47), toe webs (52), palms (26), fingernails (29), and toenails (42). Patients were treated with oral itraconazole until clinical and mycologic remission were achieved. Response rates and mean times to recovery were as follows: trunk, 100%, 1.5 months; soles, 83%, 6.7 months; toe webs, 90%, 7.2 months; palms, 96%, 4.6 months; fingernails, 90%, 5.4 months; and toenails, 76%, 10.3 months). In a 6-month follow-up period 7 of 30 patients with toenail infections who had responded to treatment had a clinical and mycologic relapse, usually of one nail. Side effects were minimal but included abdominal discomfort (three patients), headache (one), and weight gain (two). No persistent abnormalities in blood biochemistry were seen, even in patients who received itraconazole for more than 9 months.

Oral carriage of yeasts in two villages in Papua New Guinea.

Oral swabs were taken from 194 subjects in two villages in Papua New Guinea. Yeasts were isolated from 103 (53.1%) individuals of which 41 (21.1%) were Candida albicans. A wide variety of other yeasts were also identified.

Keratomycosis caused by Dichotomophthoropsis nymphaearum.

A case of Dichotomophthoropsis nymphaearum, a dematiaceous hyphomycete, is described from Bangladesh. This species has not previously been reported as a human pathogen. Hyphae were observed in Gram stained corneal scrapings and the species was grown from cultured corneal material. Treatment with topical econazole and subconjunctival injections of miconazole was successful in the short term but long-term outcome could not be determined. The results of sensitivity tests for six antifungal drugs are reported for the isolate.

Dermatophyte fungi in the Guinea Savannah region of Nigeria and the changing phase of dermatophytosis in Nigeria.

Approximately 8,000 patients with various skin diseases were seen at the Ahmadu Bello University Teaching Hospital, Kaduna, Nigeria between January 1983 and December 1986. 174 (2.2%) presented with features in which a clinical diagnosis of superficial fungal infection was made or suspected. 69 out of 190 (36.3%) of specimens taken from skin lesions or nails from these patients were mycologically positive. The fungi isolated were Trichophyton rubrum (24.6%), Tr. soudanense (13.0%), Candida albicans (5.8%) Hendersonula toruloidea (2.9%), Microsporum audouinii (1.5%) and Epidermophyton floccosum (1.5%); 34.8% of the specimens were positive on microscopy but failed to grow. Malassezia furfur was demonstrated in 15.9% of the 69 positive specimens.

An evaluation of itraconazole in the management of onychomycosis.

At present the reported use of itraconazole, a new oral triazole antifungal, has been confined to short-term treatments. This investigation is an appraisal of itraconazole in the treatment of three different forms of onychomycosis. Six patients with nail infections due to Candida albicans not associated with paronychia affecting a total of 20 nails received itraconazole (100 mg daily) for a mean period of 5.9 months. Complete remission was achieved in all cases. Twenty six patients with dermatophyte onychomycosis affecting a total of 45 finger and 80 toe-nails were treated with itraconazole (100-200 mg daily). In 24 cases the causative organism was Trichophyton rubrum. Remission was achieved in 64% of finger and 73% of toe-nails in 5 and 9.4 months, respectively. Treatment failures were experienced in patients with finger-nail infections due to T. violaceum (I) and those concurrently receiving phenytoin and phenobarbitone (3). Three patients with infections due to Hendersonula toruloidea failed to respond to treatment. Adverse effects were experienced by four patients (abdominal discomfort 3, diarrhoea I), but none were serious enough to lead to abandonment of treatment. No persistent changes were seen in serum biochemical values. This study suggests that itraconazole is potentially effective in the long-term treatment of superficial fungal infections such as onychomycosis, and comparative studies with alternatives such as griseofulvin should now be carried out.