Onychomycosis Incidence in Type 2 Diabetes Mellitus Patients

The onychomycosis incidence was determined in 250 type 2 diabetes mellitus (T2DM) patients who were registered at the Internal Medicine Service from a Mexico city General Hospital throughout a year (January-December 2006). Out of the total of studied T2DM patients, 93 (37.2%) showed ungual dystrophy and from these, in 75.3% a fungal etiology was corroborated. Out of 70 patients, 34 were men and 36 women, with an average of 63.5 years. Correlation between T2DM evolution time and onychomycosis was significant (P < 0.01). Distal-lateral subungual and total dystrophic onychomycosis were the most frequent clinical types (55.1% and 33.7%, respectively). Fifty-eight fungal isolates were obtained; 48.6% corresponded to dermatophytes, Trichophyton rubrum being the first species (37.1%). All these strains corresponded to two morphological varieties: "yellow" and typical downy. From the yeast-like isolates, 12 corresponded to Candida spp., firstly C. albicans and C. parapsilosis; three to Cryptococcus spp. (C. albidus, C. uniguttulatus and C. laurentii); two Trichosporon asahii; and only one to Pichia ohmeri. Six non-dermatophytic molds were isolated: two Chrysosporium keratinophylus, two Scopulariopsis brevicaulis, one Aspergillus fumigatus, and one Acremonium sp. The fungal mixture corresponded to T. mentagrophytes with C. guilliermondii; T. mentagrophytes with C. glabrata; T. rubrum with C. glabrata; T. rubrum with P. ohmeri.     

广州地区甲真菌病致病真菌的变迁趋势研究

目的为了解广州地区甲真菌病的致病菌种分布情况.方法笔者采用真菌培养法对临床症状典型或镜检阳性的甲真菌病病甲进行培养.结果分离出致病真菌618株,其中皮肤癣菌417株,占67.5%,酵母菌149株,占23.8%,霉菌54株,占8.7%.结论广州地区的甲真菌病的致病菌除皮肤癣菌外,酵母菌,霉菌也占一定的比例,近几年酵母菌感染有上升趋势.     

Prevalence ofCandida ciferrii in elderly patients with trophic disorders of the legs

In order to define the prevalence ofCandida ciferrii in onychomycosis, the fungal biota associated with toe nail onyxis was examined in 50 elderly patients with trophic disorders of the legs and in 220 patients without clinical evidence of trophic disorders.Candida ciferrii was more frequent in the first group of patients since it was recovered from 24% of these patients, whereas its prevalence was only 1.4% in the control group. Moreover, the positivity of the direct examination of toe nail scrapings, the absence of any other associated pathogens, and the repeated isolation of this yeast species for some of the patients confirmed its pathogenicity.Abbreviations 5-FC 5-fluorocytosine - IHEM Institut d'Hygiène et d'Epidémiologie, Section Mycologie - YPDA yeast extract-peptone-dextrose-agar     

芝加哥天蓝法在甲屑真菌检测中效果的评估

目的探讨芝加哥天蓝染色法对甲真菌病患者标本检测效果。方法收集皮肤科门诊确诊的甲真菌感染患者标本160例,同时用KOH湿片法、荧光染色法和芝加哥天蓝染色法对真菌进行镜下形态学观察,并比较真菌检出率。结果芝加哥天蓝染色法和荧光染色法对真菌的形态结构清晰易辨。芝加哥天蓝染色法、荧光染色法和KOH湿片法的检出率分别为60.6%、68.5%、47.5%;荧光染色法与芝加哥天蓝染色法的检出率结果比较差异无统计学意义(χ~2=0.176 2,P=0.674 0),芝加哥天蓝染色法和荧光染色法与KOH湿片法的结果比较差异有统计学意义(χ~2=102.012 9,P0.000 1;χ~2=57.010 3,P0.000 1)。结论如实验室没有荧光显微镜,芝加哥天蓝染色法检测甲真菌病患者标本效果较好。     

Evaluación de la utilidad diagnóstica de la biopsia ungueal en las onicomicosis

BackgroundOnychomycosis affects between 2% to 30% of the world population. Nail biopsy may help in making a diagnosis and can distinguish between invasion and colonisation.AimsTo evaluate the diagnostic usefulness of nail biopsy with Periodic acid–Schiff (PAS) staining for onychomycosis, compared to direct KOH examination, culture and its combination in a reference laboratory in Colombia.MethodsThe study included 66 patients in whom a blind and independent reading of the three tests was performed. The usefulness was defined based on the validity (sensitivity, specificity, Youden's index, likelihood ratios), performance (predictive values) efficiency (proportion of correctly diagnosed patients), and reproducibility (kappa coefficient).ResultsThe mean age of the patients was 55 ± 16 years, and included 76% women. The direct tests with KOH were positive in 66.7% (n = 44), 62.1% (n = 41) were positive with culture, and 56.1% (n = 37) with the biopsy. The main causal agents were non-dermatophytes moulds in 36.4% (n = 24). The most frequent species were Neoscytalidium dimidiatum (n = 11), Trichophyton rubrum (n = 11), and Candida parapsilosis (n = 13). The sensitivity of nail biopsy, when compared to the standard (KOH and/or culture), was 71%, specificity 83%, Youden's index 0.54, positive likelihood ratio 4.25, negative likelihood ratio 0.35, positive predictive value 92%, negative predictive value 52%, efficiency 74% and kappa coefficient 0.45. When biopsy was evaluated only in patients with onycholysis of the nail plate greater than 50%, all the parameters of diagnostic usefulness increased.ConclusionsThe overall usefulness of the biopsy was moderate for patients with more severe symptomatology, which makes its use advisable in cases of extensive onycholysis, and when discriminating colonisation from invasion is required.     

Modified PAS stain: A new diagnostic method for onychomycosis

BackgroundOnychomycosis is the most common nail disease and represents around 50% of nail disorders. Accurate diagnosis with adequate evidence is ideal before starting any treatment. Current diagnostic methods offer low specificity and sensitivity.AimsTo create a new method for the diagnosis of onychomycosis, and to compare its sensitivity and specificity with the existing methods.MethodsOne hundred and ninety-two samples with clinical suspicion of onychomycosis were included and underwent modified PAS stain (M-PAS), KOH/chlorazol black (KOH/CB) and culture testing. Sensitivity, specificity, positive and negative predictive values were calculated.ResultsIn 152 out of 192 samples (79.2%) fungi structures were found in at least one of the three tests performed, and the patients were diagnosed with onychomycosis; 40 samples out of 192 (20.8%) were negative. Using M-PAS, filaments and/or spores were seen in 143 samples from the 152 positive (94%); 39 of them were negative to KOH/CB and positive to M-PAS (25.6%). With KOH/CB, filaments and/or spores were seen in 113 cases from the 152 positive samples (73.8% of the onychomycosis cases). Thirty-five cultures were positive, of which 77% were identified as Trichophyton rubrum; 117 onychomycosis cases were diagnosed despite the negative culture (76.9%). M-PAS showed 92.5% sensitivity and 55.55% specificity, a 67.5% positive predictive value and a 81.6% negative productive value.ConclusionsThis procedure, a combination of the existing methods to diagnose onychomycosis, KOH/CB together with a nail clipping biopsy, proved to have high sensitivity, as well as being rapid, easy, inexpensive and readily available in most hospital settings. M-PAS allowed us to diagnose 39 cases (25.6% of the cases of onychomycosis) that were false negative using only KOH/CB and culture.     

荧光染色法和传统KOH湿片法在甲真菌病诊断中的应用比较

目的探讨真菌荧光染色法与传统KOH湿片法在临床甲真菌镜检中的应用效果。方法选择2017年6月至2018年4月我院600例皮肤科门诊就诊疑似真菌感染患者指(趾)甲镜检标本,分别运用荧光染色法和KOH湿片法对这些标本进行检测,记录实验数据,并对检测结果进行比较。结果荧光染色法检测阳性为418例,阳性率为70%,其中指甲阳性130例,趾甲阳性288例。KOH湿片法检测阳性为354例,阳性率为59%,其中指甲97例,趾甲257例。指甲(χ²=8.816,P=0.003)、趾甲(χ²=7.884,P=0.005)及总阳性率(χ²=14.876,P<0.001)在两种方法中差异均有统计学意义。结论在对指(趾)甲真菌感染的诊断中,荧光染色法的阳性检出率明显高于KOH湿片法,是一种快速、准确的真菌镜检方法,值得临床推广使用。     

Amino acid- or protein-dependent growth of Trichophyton mentagrophytes and Trichophyton rubrum

Culture conditions were examined for Trichophyton mentagrophytes and Trichophyton rubrum, which are major pathogens involved in dermatophytosis. They grew well in Sabouraud's dextrose broth or RPMI 1640. Growth in phosphate-buffered yeast nitrogen base supplemented with glucose was very slow, although growth improved significantly with the addition of amino acids or proteins to the medium. The fungi could also grow using human nail fragments as the only source of nutrition. Examination of proteases by substrate gel electrophoresis indicated that distinct sets of proteases are secreted from the dermatophytes in two different media, Sabouraud's dextrose broth and nail fragments. A protease inhibitor, phenylmethanesulfonyl fluoride, inhibited the growth of the fungi on nail fragments, but it did not inhibit their growth in Sabouraud's dextrose broth.     

Level of trace elements in serum and toenail samples of patients with onychocryptosis (ingrown toenail) and onychomycosis

BackgroundOnychocryptosis (ingrown toenail) and onychomycosis are common pathologies of the toenail and affecting many people. Since levels of trace elements have been shown to vary in certain diseases, in the presented work, chromium (Cr), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), selenium (Se), and zinc (Zn) levels of toenail and serum samples of healthy individuals and patients with onychocryptosis and onychomycosis were compared.MethodsSerum and toenail samples of 88 voluntary subjects (healthy n = 24; onychomycosis n = 24; onychocryptosis n = 40) aged between 19–80 years were collected. Levels of trace elements in the samples were analyzed by using an inductively coupled plasma-optical emission spectrophotometer (ICP-OES Thermo iCAP - 6000). The differences in medians between the groups for elements were evaluated with Kruskal -Wallis H test with post hoc for pairwise comparisons in SPSS 18.ResultsMg (p < 0.001) and Mn (p = 0.002) levels were significantly increased whereas Zn (p = 0.011) level was decreased in toenails of patients with onychomycosis compared to healthy subjects. Although Mg and Mn levels were higher in female subjects with onychomycosis (p = 0.001; p = 0.019), Mn was only increased in male subjects (p = 0.015). Mg was the only trace element found to be independent of sex, age, and smoking status in patients with onychomycosis. However, no significant difference has been found in serum trace element levels neither between any groups nor toenail trace element levels of patients with onychocryptosis and healthy subjects.ConclusionAs a response of the human body to pathogens like fungi in toenails, Mg, Mn and Zn levels vary. Especially the role of Mg ions in onychomycosis needs to be investigated more specifically.     

Onychomycosis in Malaysia

The common etiological agents of onychomycosis are dermatophytes, molds and yeasts. A mycological nail investigation of onychomycosis using direct microscopy and culture was conducted by the Mycology Unit, Department of Medical Microbiology, University of Malaya from March 1996 to November 1998. The study involved 878 nail clippings or subungal scrapings from subjects with onychomycosis. On direct microcopy examination, 50% of the specimens were negative for fungal elements. On culture, 373 specimens had no growth; bacteria were isolated from 15 nail specimens. Among the 490 specimens with positive fungal cultures, 177 (36.1%) were dermatophytes, 173 (35.5%) were molds and 130 (26.5%) were Candida. There were 2% (10/490) mixed infections of molds, yeasts and dermatophytes. Trichophyton rubrum (115/177) and Trichophyton mentagrophytes (59/177) were the main dermatophytes isolated. The molds isolated were predominantly Aspergillus niger (61/173), Aspergillus nidulans (30/173), Hendersonula toruloidea (26/173) and Fusarium species (16/173). 96.9% of the Candida species identified were Candida albicans.This revised version was published online in October 2005 with corrections to the Cover Date.