In vitro susceptibility of filamentous fungi to itraconazole.

The in vitro activity of itraconazole was investigated against 25 clinical isolates of filamentous fungi by agar dilution method. The isolated included Aspergillus sp., hyalohypomycetes, dematiaceous fungi and zygomycetes. Intraconazole was more active, inhibiting 50% (MIC 50) and 90% (MIC 90) of the Aspergillus sp., at a concentration of 0.5 and 2.5 ug ml-1 (MIC range 0.1 and 5 micrograms ml-1) Ketoconazole (MIC range 0.5-10 ug ml-1) required 1 and 5 ug ml-1 for inhibiting 50% and 90% of the isolates. For the hyalophypomycetes and dematiaceous fungi, the MIC 50s for itraconazole were 1 and 0.5 ug ml-1 and Ketoconazole required 2.5 ug ml-1 for both the groups. For the zygomycetes, the MIC range and MIC 50s for Ketoconazole were 1-100 and 10 ug ml-1 whereas the values for itraconazole were 5- > 100 and > 100 micrograms ml-1.

Disk diffusion susceptibility testing of dermatophytes with imidazoles.

In vitro susceptibility testing of 43 isolates of dermatophytes was carried out against imidazoles-ketoconazole, miconazole and econazole and griseofulvin by agar dilution and disk diffusion methods. Econazole was the most effective drug inhibiting all the isolates at a concentration of 0.1 microgram ml-1. The MIC 50s and MIC 90s for ketoconazole and miconazole were 1 and 2.5 mg ml-1 whereas the values for griseofulvin were 1 and 5 micrograms ml-1. Good correlation was seen between the MIC and sizes of zones of inhibition around the disks. Regression analysis was used to measure the degree of correlation between the MIC values and matched averaged zones of inhibition and the correlation coefficients for econazole, ketoconazole, miconazole and griseofulvin were -0.5554, -0.5886, -0.8558 and -0.8268 (p < 0.001) respectively.

Pale grain eumycetomas in Madras.

Biopsy specimens from 211 cases of mycetoma were examined histologically. Pale grain eumycetoma was found in seven cases. Four of these were studied mycologically, Acremonium kiliense was isolated from two and Acremonium falciforme and Pseudallescheria boydii from one case each. The geographic distribution of these organisms, and their incidence and prevalence are discussed.

Antimycotic susceptibility testing of mould-fungi with allylamines by disk diffusion.

Susceptibility testing of 17 clinical isolates of mould-fungi, which included Aspergillus spp., (8) Penicillium spp., (2) Paecilomyces spp., (1) Cladosporium spp., (1) Pyrenochaeta romeroi (1) Rhizopus spp., 2. Syncephalastrum spp., (1) and Mortierella spp., (1) were carried out against allylamines-naftifine and terbinafine-(Sandoz Forchungsinstitut) by agar dilution and disk diffusion techniques. Terbinafine was more active than naftifine inhibiting 50 and 90% of the fungi other than zygomycetes at a concentration of 0.5 and 1 microgram/ml whereas the values for naftifine were 2.5 and 10 micrograms/ml. The MIC range for zygomycetes for terbinafine and naftifine were 1-->100 and 100-->100 respectively. The MICs and the sizes of zones of inhibition around the disks correlated well and the degree of correlation was measured by regression analysis. The correlation coefficients for naftifine and terbinafine were-0.9597 and -0.9174 (P < 0.007) respectively.

Antidermatophytic activity of garlic (Allium sativum) in vitro.

BACKGROUND: Interest in herbal medicine is enjoying a renaissance at present. Garlic (Allium sativum) is an intriguing herb with a long history of medicinal use for a variety of diseases including ringworm infections. METHODS: Antidermatophytic activity of the aqueous extract of garlic (A. sativum) was investigated against 88 clinical isolates of dermatophytes by an agar dilution technique. The isolates included Microsporum canis (50), M. audouinii (5), Trichophyton rubrum (6), T. mentagrophytes (5), T. violaceum (12), T. simii (5), T. verrucosum (1), T. erinacei (1), and Epidermophyton floccosum (2). The results were compared with the minimal inhibitory concentrations of ketoconazole. RESULTS: The aqueous extract of garlic, diluted 1:150 and 1:100, had inhibited 50 and 90% of the isolates tested, whereas the respective values for ketoconazole were 1 and 2.5 micrograms/mL. CONCLUSIONS: Garlic (A. sativum) could be used as an effective antidermatophytic agent. Further purification and extraction of the active principle of garlic would give a true antidermatophytic activity comparable to standard antifungal drugs.

Disk diffusion susceptibility testing of dermatophytes with allylamines.

BACKGROUND: Allylamines are a newly developed group of drugs possessing a broad spectrum of activity against a wide range of fungi. With the advent of new antifungal drugs, susceptibility testing of fungi is receiving increased attention as important laboratory procedures for aiding in the selection of appropriate drug therapy. METHODS: In vitro susceptibility testing of 43 clinical isolates of dermatophytes which included Microsporum sp., (18) Trichophyton sp., (23) and Epidermophyton floccosum (2) were carried out against the two allylamine derivatives, naftifine and terbinafine, by agar dilution and disk diffusion methods. RESULTS: Terbinafine was found to be more active minimal inhibitory concentration (MIC range < or = 0.0001-0.1 micrograms/mL), inhibiting 50% (MIC 50) and 90% (MIC 90) of the isolates at 0.01 and 0.1 micrograms/mL, respectively. The MIC 50s and MIC 90s of naftifine were 0.1 micrograms/mL (MIC range 0.001-0.5 micrograms/mL). Both the drugs showed good correlation between the MIC and sizes of zones of inhibition around the disks. Regression analysis was used to measure the degree of correlation between the MIC values and matched averaged zones of inhibition; the correlation coefficients for both terbinafine and naftifine were -0.6841 (P < 0.001) and -0.5455 (P < 0.001), respectively. CONCLUSIONS: The allylamines, naftifine and terbinafine, could be used successfully for susceptibility testing of dermatophytes by the disk diffusion method. With proper standardization of the test conditions, in vitro susceptibility testing of filamentous fungi by disk diffusion would become a useful laboratory procedure in the near future for determining the best drug therapy.

Antidermatophytic activity of allylamine derivatives.

The allylamine derivatives are a new class of synthetic antifungal agents. The antidermatophytic activity of the two main compounds, naftifine and terbinafine were compared in vitro with those of ketoconazole and itraconazole by agar dilution. Eighty eight clinical isolates of dematophytes comprising of Microsporum canis (50), M. audouinii (5), Trichophyton rubrum (6) T. mentagrophytes (5), T. violaceum (12), T. simii (5), T. verrucosum (1), T. soudanense (1), T. erinacie (1) and Epidermophyton floccosum (2) were tested. Terbinafine was found to be most active, inhibiting 68 of the 88 isolates at a concentration of 0.01 ug ml-1 and all at 0.1 ug ml. (Minimum inhibitory concentration - MIC range < or = 0.0001-0.1 ug ml-1). Naftifine inhibited 84 isolates at a concentration of 0.1 ug ml-1 and all at 0.5 ug ml-1 (MIC range 0.001-0.5 ug ml-1). Itraconazole required 0.1 ug ml-1 for inhibiting 50 isolates and 0.5 ug ml-1 for 85 isolates (MIC range 0.01-1 ug ml-1) whereas ketoconazole inhibited 71 isolates at 1 ug ml-1 and 87 at 2.5 ug ml-1 (MIC range 0.01-5 ug ml-1).

Antifungal activity of allylamine derivatives.

The antifungal activity of the two allylamine derivatives, naftifine and terbinafine was investigated against 25 clinical isolates of filamentous fungi by agar dilution method. The isolates included Aspergillus sp. (10), Penicillium sp. (3), Cladosporium sp. (3), Rhizopus sp. (3), Paecilomyces sp. (2), Syncephalastrum sp. (1), Pyrenochaeta romeroi (1), Piedraia hortae (1) and Mortierella sp. (1). Terbinafine was found to be more active than naftifine, inhibiting 50 per cent (MIC 50) and 90 per cent (MIC 90) of the isolates of Aspergillus sp., at 0.1 and 0.5 microgram/ml respectively. The MIC 50s for the other isolates of hyalohyphomycetes, dematiaceous fungi and zygomycetes were 1, 5 and 100 micrograms/ml respectively. Naftifine inhibited 50 and 90 per cent of the Aspergillus sp., at 1 and 5 micrograms/ml, respectively. The MIC 50s for the other hyalohyphomycetes, dematiaceous fungi and zygomycetes were 5, 10 and 100 micrograms/ml respectively.

Treatment of eumycetoma with ketoconazole.

Ten patients with eumycetoma were treated with oral ketoconazole in the dosage of 400mg/day for 8 to 24 months. In eight cases the foot was affected: four were due to Madurella mycetomatis and one each due to M grisea, Pyrenochaeta romeroi, Acremonium kiliense and A falciorme. One mycetoma which affected the back and perineum was due to A kiliense, and one case presented with multiple sebaceous cysts and the scalp and M mycetomatis was isolated from the lesion. Clinical and laboratory tests showed excellent tolerance to the drug, with no adverse reactions. Complete cure was obtained in six patients and two showed good responses. The cured patients were followed up for a period ranging from three months to two years without any evidence of recurrence.

Antimycotic susceptibility testing of agents of black grain eumycetoma.

Antimycotic susceptibility testing of 17 strains of eumycetes including Madurella mycetomatis, Madurella grisea, Pyrenochaeta romeroi, Exophiala jeanselmei and Leptosphaeria tompkinsii, isolated from cases of black grain mycetoma, was carried out against ketoconazole, itraconazole, miconazole and econazole by broth microdilution and agar dilution methods. Itraconazole and ketoconazole were more active inhibiting 50% of the strains (MIC 50) at 0.5 and 1 microgram ml-1 and 90% (MIC 90) at 2.5 and 5 micrograms ml-1, respectively. The MIC 50s of econazole and miconazole were 2.5 and 5 micrograms ml-1 and MIC 90s 10 micrograms ml-1 for both drugs.

Tinea capitis in Saudi Arabia.

BACKGROUND: Tinea capitis is a dermatophyte infection of the scalp, eyebrows, and eyelashes caused by species of Microsporum and Trichophyton. The purpose of this study was to discover the incidence and causal agents of tinea capitis in Saudi Arabia. METHODS: Hair roots, skin scrapings, and pus swabs were collected from patients clinically diagnosed with tinea capitis and were processed for fungus. RESULTS: Of 372 patients with tinea capitis investigated in Saudi Arabia, 240 were found to be positive by direct microscopic examination, and the causal agent was isolated from 237 patients. Tinea capitis accounted for 47.7% of all superficial mycoses, and 97% of it occurred in children below 15 years of age. Inflammatory lesions were found in 35% of cases, and 10 of them presented with kerion celsi. Favus-type lesion was found in one. Microsporum canis was the most common etiologic agent, responsible for 82.3% of the infections. Trichophyton violaceum was the next most common agent (13.9%), followed by M. audouini (2.2%); T. mentagrophytes, T. rubrum, T. verrucosum, and T. simii were isolated from one patient each. This is the first report of T. simii infection in a Saudi man. CONCLUSIONS: Although none of the patients owned pets, the predominance of M. canis may be explained by the large number of cats in the neighborhood. The disappearance of favus due to T. schoenleinii may be due to improved socioeconomic conditions. Our results agreed with two previous reports.

Superficial mycoses in Saudi Arabia.

Between June 1988 and December 1990, 1018 cases of superficial mycoses were investigated. Diagnosis was confirmed by microscopic examination in 503 cases and the causal agent was isolated in 490 cases. Tinea capitis accounted for 47.7% (92.5% in children below 10 years of age). The frequency of other clinical types in descending order was pityriasis versicolor 25.8%, tinea corporis 9%, onychomycosis 5.8%, tinea pedis 4%, intertrigo 3.9% and tinea cruris 2.8%. Erythrasma was encountered three times and mixed piedra and trichomycosis axillaris once. Microsporum canis was the commonest aetiological agent, responsible for 46.9% of ringworm infections. Malassezia furfur was the next most common agent (26.5%) followed by Candida albicans (8.6%) and Trichophyton violaceum (8.2%). Other species were found less frequently. T.simii was isolated from four cases of tinea cruris and one each of tinea capitis and tinea corporis, and Piedraia hortae and Trichosporon beigelii from a case of mixed piedra infection.

Actinomadura madurae mycetomas.

Actinomycetomas are localised, chronic, suppurative and progressive infections of the skin, subcutaneous tissues and bones caused by aerobic actinomycetes. They are characterised by subcutaneous granulomas and abscesses with induration, formation of sinus tracts and production of granules which are the microcolonies of the causative agents.

Cerebral aspergillosis: report of two cases.

Two cases of cerebral aspergillosis in Tamilians presenting as intracranial space-occupying lesions are reported. The first patient had a left frontal lobe abscess and a specific diagnosis was made by histopathology and isolation of Aspergillus versicolor. He responded well to excision followed by anticonvulsant therapy. In the other, the diagnosis was based on histopathology alone and she died after surgery. These are the first cases reported from Tamil Nadu and probably only one similar case has been reported from India so far.

Mycetomas in Madras.

In 90 of 150 cases clinically diagnosed as mycetoma in the Department of Pathology, Madras Medical College, from January 1964 to June 1975, histopathological study revealed granules. Besides special staining procedures, cultural methods were undertaken in recent cases. The age and sex incidence, site of lesion and the species of fungi identified on the basis of histological morphology of the granules are analysed. The disease was predominatly seen in the age group 21-40. Men were more frequently affected than women and the commonest site of the lesion was foot. Actinomycotic mycetoma (68-9%) was more often found than the maduromycotic type. Madurella mycetomi (37-8%) and Actinomadura madurae (26-7%) were the commonest causal agents. Nocardia spp. were the next most common (21-1%) followed by A. pelletieri (15-5%), S. somaliensis (5-6%) and presumably Allescheria/Cephalosporium spp. from only 3 cases of white grain mycetoma.