1% clotrimazole more effective than 3% boric acid in alcohol for otomycosis: randomised trial
March 27 2017
In a randomised controlled trial 1% clotrimazole solution has been found to tbe more effective at treating otomycosis than its cheaper alternative, 3 per cent boric acid in 70 per cent isoproypyl alcohol. Otomycosis is a worldwide superficial fungal infection of the external auditory canal and auricle which is more prevalent in tropical zones.
Dr Romsaithong and colleagues compared 1 per cent clotrimazole solution with 3 per cent boric acid in 70 per cent alcohol at Khon Kaen Hospital, Thailand, where otomycosis has been reported in 11 per cent of patients presenting with inflammatory conditions of the ear canal. The trial was double-blind, controlled and randomised, trial and patients patients’ ear canals were examined under the operating microscope one week after a single application of the treatment. Their condition was either classified as cured or not cured, based on the presence or absence of fungus.
The cure rate for the clotrimazole group was significantly higher with 85.2%, compared to 67.3% for the boric acid group, giving an absolute difference of 17.9% (p = 0.028). The results of this study concurred with similar previous controlled trials.
The secondary outcome of the study revealed that patients treated with clotrimazole also reported fewer adverse events. While this study lacked long-term follow up of treatments, it was evident that a single application of 1 % clotrimazole solution is both more effective at treating otomycosis and less irritating than 3% boric acid in 70 per cent alcohol.
Invasive fungal infections: High mortality and new underlying diseases in Middle East
March 20 2017
A retrospective study of 102 hospitalised patients with invasive candidiasis or aspergillosis in Saudi Arabia and Lebanon (Alothman et al 2017) identifies several non-traditional common co-morbidities including coronary artery disease (24%), congestive heart failure (15%), moderate-to-severe renal disease (16%), and diabetes (41%). In selected and diagnosed patients, some immunocompromising factors were also present, notably corticosteroids prior to admission (20%) and chemotherapy in the prior 3 months (26%). The authors caution their peers: “Earlier consideration ... of IFI in medically comorbid patients may reduce the time to antifungal treatment and improve outcomes.”
This study also highlights a high mortality of 42%, mean hospitalisation period of 32 days, the low use of Aspergillus galactomannan testing (11%), and the delay before a diagnosis of invasive fungal infection was made. They note that the median time from admission to diagnosis was 6 days (range 0 to 92 days), and it took another day for antifungal therapy to be started. A median of 2.5 days (range −3 to 80 days) elapsed between culture collection and treatment given. Fluconazole was the favoured antifungal, but over 50% of the infections were resistant to it.
Efficacy of in-house fluorescent stain for fungus
March 15 2017
Increasing numbers of immunocompromised patients means that correctly diagnosing fungal infections is becoming more and more critical. Conventional diagnostic methods may not be the most effective, especially when there are small amounts of the causal agent in a sample. In a recent study of diagnostic tests for fungal infections, Kirani and Chandrika (2017) looked at the efficacy of an in-house calcofluor white (CFW) fluorescent stain, compared to conventional CFW stain, histopathology and culture. They also determined the sensitivity, specificity, negative predictive value and positive predictive value. The authors compared the results of the in-house fluorescent stain to the conventional stain with 100 cases of suspected dermtophytosis and found that the tests agreed perfectly (35 positive, 65 negative). The samples were then compared using culture, which found 30 positive samples and 70 negative samples. They also compared the results 15 tissue section smears from clinically diagnosed fungal infections using the in-house stain and standard histopathological techniques. Using the in-house stain, 12 samples showed evidence of fungal infections (Aspergillus, Mucor, Candida, Rhinosporidium seeberi and Pneumocysttis carinii) whereas conventional histopathology identified only 10 positive samples.
Banana peel culture as an indigenous medium to induce sporulation for identification
March 13 2017
More fungi are known as human pathogens now and these include newer and rarer species. Identifying these species from growth on conventional culture media tends to be challenging due to the absence of characteristic features. An indigenous and cheap culture medium, similar to the natural substrate of these fungi is needed to aid diagnosis in a conventional laboratory setting.
Kindo and colleagues (2016) developed a media using sterilised banana peel as substrate for the growth and isolation of some rare fungi. This was done by taking unidentifiable fungi on primary isolation media and inoculating them on banana peel pieces along with few sterile coverslips, covered and kept at room temperature for 10-15 days. An un-inoculated separate plate of sterilised banana peel served as the negative control. Fungi grown were then identified microscopically based on their characteristic morphology.
The researchers were able to identify six of the rarer human pathogenic ascomycetes (Lasiodiplodia theobromae, Macrophomina phaseolina, Nigrospora sphaerica, Chaetomium murorum), coelomycetes (Nattrassia mangiferae) and basidiomycetes (Schizophyllum commune) fungi. This method was found to be easy, affordable and effective.
Other methods of inducing fungi to sporulate include plating onto potato dextrose agar, Czapek Dox agar, or directly sending for sequencing.
THE BURDEN OF FUNGAL DISEASE: NEW EVIDENCE TO SHOW THE SCALE OF THE PROBLEM ACROSS THE GLOBE
February 28 2017
Estimates never before attempted show the number of people affected by serious fungal diseases in 14 of the worst affected countries across the globe have just been published *.
Experts believe they give a stark reminder of the huge disconnect between the lack of fungal public health programs worldwide and the wealth of scientific research information on fungal disease now available.
In a themed issue of journal European Journal of Clinical Microbiology and Infectious Diseases, the number of people affected by serious fungal diseases has been estimated for 832 million people in 14 countries in Asia, the Americas, Europe and North Africa. These estimates show that between 1.8-3 per cent of the population of each country are affected by some of the most serious types of fungal disease, which can cause chronic illness and death in the most extreme cases.
The countries scrutinised are Pakistan, Bangladesh, South Korea, the Philippines, Thailand, and Uzbekistan, Ecuador, Canada, Peru, Guatemala, Chile; Portugal and Algeria and Egypt.