A global view on fungal infections in humans and animals: opportunistic infections and microsporidioses.

After cardiovascular diseases, infectious diseases are the second most common cause of death worldwide. Although these infections are caused mainly by viruses or bacteria, a systematically growing prevalence of human and animal opportunistic fungal infections is noticeable worldwide. More attention is being paid to this problem, especially due to the growing frequency of recalcitrant and recurrent mycoses. The latter are classically divided into superficial, which are the most common type, subcutaneous, and systemic. This work discusses opportunistic fungal pathogens without proven horizontal transmission between different animal species including humans and microsporidia as spore-forming unicellular parasites related to fungi; however, with a yet undetermined taxonomic position. The review also mentions aetiological agents, risk factors, epidemiology, geographical distribution, and finally symptoms characteristic for individual disease entities. This paper provides insight into fungal infections from a global perspective and simultaneously draws attention to emerging pathogens, whose prevalence is continuously increasing. Finally, this work also takes into consideration the correct nomenclature of fungal disease entities and the importance of secondary metabolites in the pathogenesis of fungal infections.

A global view on fungal infections in humans and animals: infections caused by dimorphic fungi and dermatophytoses.

Fungal infections are still underappreciated and their prevalence is underestimated, which renders them a serious public health problem. Realistic discussions about their distribution, symptoms, and control can improve management and diagnosis and contribute to refinement of preventive actions using currently available tools. This article represents an overview of dermatophytes and endemic fungi that cause infections in humans and animals. In addition, the impact of climate change on the fungal spread is discussed. The endemic fungal infections characterized in this article include coccidioidomycosis, histoplasmosis, blastomycosis, lobomycosis, emergomycosis and sporotrichosis. Moreover the geographic distribution of these fungi, which are known to be climate sensitive and/or limited to endemic tropical and subtropical areas, is highlighted. In turn, dermatophytes cause superficial fungal infections of skin, hairs and nails, which are the most prevalent mycoses worldwide with a high economic burden. Therefore, the possibility of causing zoonoses and reverse zoonoses by dermatophytes is highly important. In conclusion, the article illustrates the current issues of the epidemiology and distribution of fungal diseases, emphasizing the lack of public programmes for prevention and control of these types of infection.

Detection and identification of dermatophytes based on currently available methods - a comparative study.

AIMS: Accurate identification of dermatophytes is essential for implementing appropriate antifungal treatment and epidemiological analysis. However, the limitations of conventional diagnostics are a frequently discussed topic, and new diagnostic techniques are constantly expanding. In this study, we assess the suitability of conventional diagnostic techniques in comparison to the real-time PCR assay and MALDI-TOF MS in detection and identification of dermatophytes. METHODS AND RESULTS: Strains included in this study were obtained from human and animals with symptomatic, and asymptomatic infection. A direct examination revealed that 31·7 and 60·9% of samples from symptomatic patients, and 25·7 and 60% from asymptomatic animals were positive, as shown by light and fluorescence microscopy respectively. In turn, dermatophytes were isolated from 90·2 and 71·4% of these samples. The pan-dermatophyte primers in real-time PCR assay facilitated detection in 85·3 and 82·9% of the symptomatic and asymptomatic dermatophytoses respectively. Additionally, species-specific PCR assays were positive in 70·7 and 37·1% of these samples. The MALDI-TOF MS analysis yielded positive results consistent with conventional techniques in 97·2 and 72% of symptomatic and asymptomatic infections respectively. CONCLUSIONS: Our study revealed that there is no universal diagnostic method that would be ideal in each of the cases considered. Nonetheless, conventional techniques are still the most effective and reliable tools for mycological diagnostics. SIGNIFICANCE AND IMPACT OF THE STUDY: Dermatologists and veterinarians have difficulties in making a diagnosis of dermatophytoses based only on observed symptoms of fungal infections, as they mimic symptoms of other dermatoses. In this context, a comparative analysis of the results of diagnostics performed using conventional methods and new technologies are crucial for implementing these pioneer methods into routine laboratory practice.

Isolation of infectious microalga Prototheca wickerhamii from a carp (Cyprinus carpio) - a first confirmed case report of protothecosis in a fish.

Protothecosis is a rare infection caused by environmentally ubiquitous achlorophyllic microalgae of the genus Prototheca. Here, we describe a first case of protothecosis in a carp (Cyprinus carpio), which is at the same time the first case of protothecosis in a fish, confirmed by phenotype- and molecular-based methods, including PCR sequencing of the rDNA cluster and protein profiling using matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

Preliminary physiological characteristics of thermotolerant Saccharomyces cerevisiae clinical isolates identified by molecular biology techniques.

UNLABELLED: The aim of the study was a molecular identification and physiological characteristic of the five Saccharomyces cerevisiae strains isolated from patients. The tested isolates were compared with control strains (which are of laboratory or commercial origin). The relation of the isolates to baker's yeast S. cerevisiae was studied using species-specific primers in PCR analysis of the ITS-26S region of DNA. Five isolates were genetically identified as the yeast belonging to the genus S. cerevisiae. The effects of temperature and carbon sources on the growth of the yeast strains were analysed. A quantitative characterization of growth kinetics approve that some tested isolates are thermotolerant and are able to grow at range 37-39°C. Among them, one representative is characterized by the highest specific growth rate (0·637 h(-1) ). In conclusions, some strains are defined as potential candidates to use in the biotechnology due to a higher growth rate at elevated temperatures. Screening for further evaluation of biotechnological significance of the tested isolates will be done (e.g. ethanol and trehalose production at higher temperatures). The physiological characterization and confirmation of species identification by molecular methods for yeasts important in the context of biotechnology industry were demonstrated. SIGNIFICANCE AND IMPACT OF THE STUDY: Thermotolerant microbial strains are required in various industrial applications, for improving productivity and for decreasing the risk of undesirable contaminations when higher temperatures are used. It is important to search for such strains in extreme environments or exotic niches. In this paper, new thermotolerant strains were identified belonging to the Saccharomyces cerevisiae, but differed from typical bakers' yeast, essentially by their growth rate at higher temperature. The described yeast strains are promising for using in biotechnological industry, especially, for production of ethanol and other products at higher temperatures.

Meta-analysis: Saccharomyces boulardii for treating acute diarrhoea in children.

BACKGROUND: Saccharomyces boulardii is a non-pathogenic probiotic yeast considered useful against enteropathogens. AIM: To assess the effectiveness of S. boulardii in treating acute infectious diarrhoea in children. METHODS: The following electronic databases were searched through August 2006 for studies relevant to acute infectious diarrhoea and S. boulardii: MEDLINE, EMBASE, CINAHL and The Cochrane Library; additional references were obtained from reviewed articles. Only randomized-controlled trials were included. RESULTS: Five randomized-controlled trials (619 participants) met the inclusion criteria. Combined data from four randomized-controlled trials showed that S. boulardii significantly reduced the duration of diarrhoea compared with control. The pooled weighted mean difference was -1.1 days (95% CI: -1.3 to -0.8) with a fixed model and remained significant in a random effect model. Saccharomyces boulardii significantly reduced the risk of diarrhoea on days 3, 6 and 7. Also the risk of diarrhoea lasting >7 days was significantly reduced in the S. boulardii group vs. control group (1 RCT, n = 88, RR 0.25, 95% CI: 0.08-0.83; NNT 5, 95% CI: 3-20). CONCLUSIONS: There exists a moderate clinical benefit of S. boulardii therapy in otherwise healthy infants and children with acute gastroenteritis, mainly a shorter duration of diarrhoea. However, these results should be interpreted with caution due to methodological limitations of the included studies.

Meta-analysis: ondansetron for vomiting in acute gastroenteritis in children.

BACKGROUND: Vomiting is a common sympton in children with gastroenteritis, but its treatment remains controversial. AIM: To investigate potential beneficial effects of ondansetron, compared with placebo or no intervention, in treating vomiting during acute gastroenteritis in children. METHODS: The following electronic databases were searched through August 2006: MEDLINE, EMBASE, CINAHL and The Cochrane Library; additional references were obtained from reviewed articles. Only randomized-controlled trials (RCTs) were included. RESULTS: Four RCTs involving 490 patients with vomiting during acute gastroenteritis were included. Combined data from three RCTs (n = 466) showed that ondansetron compared with the control significantly increased the chance for vomiting cessation soon after drug administration [relative risk (RR): 1.3, 95% confidence interval (CI): 1.2-1.5, number needed to treat (NNT): 5, 95% CI: 4-8], but this effect was not observed at 24 h (three RCTs, n = 144, RR 1.2, 95% CI: 0.9-1.7). Ondansetron significantly reduced the risk of intravenous rehydration (two RCTs, n = 359, RR 0.4, 95% CI: 0.3-0.7, NNT 7, 95% CI: 5-14). Outcome measures not significantly different after ondansetron treatment were the need for hospitalization and return emergency department visits. CONCLUSIONS: Despite some clinical benefits, there is insufficient evidence to recommend the routine use of ondansetron for vomiting during acute gastroenteritis in children.