Shallu Kathuria

ESCMID and ECMM Joint Clinical Guidelines for the Diagnosis and Management of Mucormycosis 2013

These European Society for Clinical Microbiology and Infectious Diseases and European Confederation of Medical Mycology Joint Clinical Guidelines focus on the diagnosis and management of mucormycosis. Only a few of the numerous recommendations can be summarized here. To diagnose mucormycosis, direct microscopy preferably using optical brighteners, histopathology and culture are strongly recommended. Pathogen identification to species level by molecular methods and susceptibility testing are strongly recommended to establish epidemiological knowledge. The recommendation for guiding treatment based on MICs is supported only marginally. Imaging is strongly recommended to determine the extent of disease. To differentiate mucormycosis from aspergillosis in haematological malignancy and stem cell transplantation recipients, identification of the reverse halo sign on computed tomography is advised with moderate strength. For adults and children we strongly recommend surgical debridement in addition to immediate first-line antifungal treatment with liposomal or lipid-complex amphotericin B with a minimum dose of 5 mg/kg/day. Amphotericin B deoxycholate is better avoided because of severe adverse effects. For salvage treatment we strongly recommend posaconazole 4×200 mg/day. Reversal of predisposing conditions is strongly recommended, i.e. using granulocyte colony-stimulating factor in haematological patients with ongoing neutropenia, controlling hyperglycaemia and ketoacidosis in diabetic patients, and limiting glucocorticosteroids to the minimum dose required. We recommend against using deferasirox in haematological patients outside clinical trials, and marginally support a recommendation for deferasirox in diabetic patients. Hyperbaric oxygen is supported with marginal strength only. Finally, we strongly recommend continuing treatment until complete response demonstrated on imaging and permanent reversal of predisposing factors.

ESCMID and ECMM joint guidelines on diagnosis and management of hyalohyphomycosis: Fusarium spp., Scedosporium spp. and others

Mycoses summarized in the hyalohyphomycosis group are heterogeneous, defined by the presence of hyaline (non-dematiaceous) hyphae. The number of organisms implicated in hyalohyphomycosis is increasing and the most clinically important species belong to the genera Fusarium, Scedosporium, Acremonium, Scopulariopsis, Purpureocillium and Paecilomyces. Severely immunocompromised patients are particularly vulnerable to infection, and clinical manifestations range from colonization to chronic localized lesions to acute invasive and/or disseminated diseases. Diagnosis usually requires isolation and identification of the infecting pathogen. A poor prognosis is associated with fusariosis and early therapy of localized disease is important to prevent progression to a more aggressive or disseminated infection. Therapy should include voriconazole and surgical debridement where possible or posaconazole as salvage treatment. Voriconazole represents the first-line treatment of infections due to members of the genus Scedosporium. For Acremonium spp., Scopulariopsis spp., Purpureocillium spp. and Paecilomyces spp. the optimal antifungal treatment has not been established. Management usually consists of surgery and antifungal treatment, depending on the clinical presentation.

Emergence of Azole-Resistant Aspergillus fumigatus Strains due to Agricultural Azole Use Creates an Increasing Threat to Human Health

Aspergillus fumigatus, a ubiquitously distributed opportunistic pathogen, is the global leading cause of aspergillosis and causes one of the highest numbers of deaths among patients with fungal infections [1]. Invasive aspergillosis is the most severe manifestation with an overall annual incidence up to 10% in immunosuppressed patients, whereas chronic pulmonary aspergillosis affects about 3 million, primarily immunocompetent, individuals each year [2]. Three triazole antifungals, namely itraconazole, voriconazole, and posaconazole, are recommended first-line drugs in the treatment and prophylaxis of aspergillosis [3]. However, azole resistance in A. fumigatus isolates is increasingly reported with variable prevalence in Europe, the United States, South America, China, Japan, Iran, and India [4]–[9]. For example, about 10% of strains of A. fumigatus from the Netherlands are itraconazole resistant, and in the United Kingdom, the frequency increased from 0%–5% during 2002–2004 to 17%–20% in 2007–2009 [10]–[13]. In the ARTEMIS global surveillance program involving 62 medical centers, 5.8% of A. fumigatus strains showed elevated MICs to one or more triazoles [5]. Similarly, the prospective SCARE (Surveillance Collaboration on Aspergillus Resistance in Europe) study involving 22 medical centers in 19 countries identified an overall prevalence of 3.4% azole resistance. Azole-resistant A. fumigatus (ARAF) ranged from 0% to 26% among the 22 centres and was detected in 11 (57.9%) of the 19 participating European countries [4 and P.E. Verweij, personal communication]. Interestingly, almost half (48.9%) of the ARAF isolates from the SCARE network in European countries were resistant to multiple azoles and harbored the TR34/L98H mutation in the cyp51A gene [4 and P.E. Verweij, personal communication]. Indeed, multi-azole resistance in A. fumigatus due to the TR34/L98H mutations has become an emerging problem in both Europe and Asia and has been associated with high rates of treatment failures [12]–[14]. Azole antifungal drugs inhibit the ergosterol biosynthesis pathway, specifically the cytochrome p450 sterol 14-α-demethylase encoded by the cyp51A gene, which leads to depletion of ergosterol and accumulation of toxic sterols. The majority of ARAF isolates contain alterations in the target enzyme and the mutated target showed reduced or no binding to the drugs [15]. While most mutations in ARAF isolates were single nucleotide substitutions in the target gene (cyp51A), mutations at other genes such as the cdr1B have also been reported. For example, in the United Kingdom the frequency of ARAF isolates without cyp51A mutations has been reported to be more than 50% [16].

Isolation of multiple-triazole-resistant Aspergillus fumigatus strains carrying the TR/L98H mutations in the cyp51A gene in India

OBJECTIVES Azole resistance in Aspergillus fumigatus isolates impacts on the management of aspergillosis since azoles are primary agents used for prophylaxis and therapy. We report the emergence of resistance to triazoles in two A. fumigatus isolates from patients in Delhi, India. METHODS One hundred and three A. fumigatus isolates, collected from 85 patients suspected of bronchopulmonary aspergillosis during 2005-10, were investigated for susceptibility to itraconazole, voriconazole, posaconazole and isavuconazole. We undertook a mixed-format real-time PCR assay for the detection of mutations leading to triazole resistance in A. fumigatus. The resistant isolates were compared with 25 Dutch TR/L98H-positive isolates by microsatellite analysis. RESULTS Of the 103 A. fumigatus isolates tested, only 2 had high MIC values of itraconazole (>16 mg/L), voriconazole (2 mg/L), posaconazole (2 mg/L) and isavuconazole (8 mg/L). The resistant A. fumigatus isolates exhibited the TR/L98H genotype and showed identical patterns by microsatellite typing, but were different from 25 Dutch TR/L98H isolates. CONCLUSIONS We report for the first time from India the occurrence of TR/L98H mutations in the cyp51A gene (responsible for reduced azole susceptibility) in two A. fumigatus isolates from patients with chronic respiratory disease who had not previously been exposed to azoles. The presence of TR/L98H is consistent with a route of resistance development through exposure to azole compounds in the environment. Given the emergence of azole resistance in environmental strains, continued surveillance of resistance in clinical A. fumigatus strains is desirable for successful therapy of aspergillosis.

Multidrug-Resistant Candida auris Misidentified as Candida haemulonii: Characterization by Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry and DNA Sequencing and Its Antifungal Susceptibility Profile Variability by Vitek 2, CLSI Broth Microdilution, and Etest Method

ABSTRACT Candida auris is a multidrug-resistant yeast that causes a wide spectrum of infections, especially in intensive care settings. We investigated C. auris prevalence among 102 clinical isolates previously identified as Candida haemulonii or Candida famata by the Vitek 2 system. Internal transcribed spacer region (ITS) sequencing confirmed 88.2% of the isolates as C. auris, and matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) easily separated all related species, viz., C. auris (n = 90), C. haemulonii (n = 6), C. haemulonii var. vulnera (n = 1), and Candida duobushaemulonii (n = 5). The in vitro antifungal susceptibility was determined using CLSI broth microdilution (CLSI-BMD), the Vitek 2 antifungal susceptibility test, and the Etest method. C. auris isolates revealed uniformly elevated fluconazole MICs (MIC50, 64 μg/ml), and an alarming percentage of isolates (37%) exhibited elevated caspofungin MICs by CLSI-BMD. Notably, 34% of C. auris isolates had coexisting elevated MICs (≥2 μg/ml) for both fluconazole and voriconazole, and 10% of the isolates had elevated coexisting MICs (≥2 μg/ml) to two additional azoles, i.e., posaconazole and isavuconazole. In contrast to reduced amphotericin B MICs by CLSI-BMD (MIC50, 1 μg/ml) for C. auris, elevated MICs were noted by Vitek 2 (MIC50, 8 μg/ml), which were statistically significant. Candida auris remains an unnoticed pathogen in routine microbiology laboratories, as 90% of the isolates characterized by commercial identification systems are misidentified as C. haemulonii. MALDI-TOF MS proved to be a more robust diagnostic technique for rapid identification of C. auris. Considering that misleading elevated MICs of amphotericin B by the Vitek AST-YS07 card may lead to the selection of inappropriate therapy, a cautionary approach is recommended for laboratories relying on commercial systems for identification and antifungal susceptibility testing of rare yeasts.

Clonal Expansion and Emergence of Environmental Multiple-Triazole-Resistant Aspergillus fumigatus Strains Carrying the TR34/L98H Mutations in the cyp51A Gene in India

Azole resistance is an emerging problem in Aspergillus which impacts the management of aspergillosis. Here in we report the emergence and clonal spread of resistance to triazoles in environmental Aspergillus fumigatus isolates in India. A total of 44 (7%) A. fumigatus isolates from 24 environmental samples were found to be triazole resistant. The isolation rate of resistant A. fumigatus was highest (33%) from soil of tea gardens followed by soil from flower pots of the hospital garden (20%), soil beneath cotton trees (20%), rice paddy fields (12.3%), air samples of hospital wards (7.6%) and from soil admixed with bird droppings (3.8%). These strains showed cross-resistance to voriconazole, posaconazole, itraconazole and to six triazole fungicides used extensively in agriculture. Our analyses identified that all triazole-resistant strains from India shared the same TR34/L98H mutation in the cyp51 gene. In contrast to the genetic uniformity of azole-resistant strains the azole-susceptible isolates from patients and environments in India were genetically very diverse. All nine loci were highly polymorphic in populations of azole-susceptible isolates from both clinical and environmental samples. Furthermore, all Indian environmental and clinical azole resistant isolates shared the same multilocus microsatellite genotype not found in any other analyzed samples, either from within India or from the Netherlands, France, Germany or China. Our population genetic analyses suggest that the Indian azole-resistant A. fumigatus genotype was likely an extremely adaptive recombinant progeny derived from a cross between an azole-resistant strain migrated from outside of India and a native azole-susceptible strain from within India, followed by mutation and then rapid dispersal through many parts of India. Our results are consistent with the hypothesis that exposure of A. fumigatus to azole fungicides in the environment causes cross-resistance to medical triazoles. The study emphasises the need of continued surveillance of resistance in environmental and clinical A. fumigatus strains.

New Clonal Strain of Candida auris, Delhi, India

A new clonal strain of Candida auris is an emerging etiologic agent of fungemia in Delhi, India. In 12 patients in 2 hospitals, it was resistant to fluconazole and genotypically distinct from isolates from South Korea and Japan, as revealed by M13 and amplified fragment length polymorphism typing.

Allergic bronchopulmonary mycosis due to fungi other than Aspergillus: a global overview

Abstract Allergic bronchopulmonary mycosis (ABPM) is a hypersensitivity-mediated disease of worldwide distribution. We reviewed 143 reported global cases of ABPM due to fungi other than aspergilli. The commonest etiologic agent was Candida albicans, reported in 60% of the cases, followed by Bipolaris species (13%), Schizophyllum commune (11%), Curvularia species (8%), Pseudallescheria boydii species complex (3%) and rarely, Alternaria alternata, Fusarium vasinfectum, Penicillium species, Cladosporium cladosporioides, Stemphylium languinosum, Rhizopus oryzae, C. glabrata, Saccharomyces cerevisiae and Trichosporon beigelii. India accounted for about 47% of the globally reported cases of ABPM, attributed predominantly to C. albicans, followed by Japan (16%) where S. commune predominates, and the remaining one-third from the USA, Australia and Europe. Notably, bronchial asthma was present in only 32% of ABPM cases whereas its association with development of allergic bronchopulmonary aspergillosis (ABPA) is known to be much more frequent. The cases reviewed herein revealed a median IgE value threefold higher than that of ABPA, suggesting that the etiologic agents of ABPM incite a stronger immunological response than that by aspergilli in ABPA. ABPM is currently underdiagnosed, warranting comprehensive basic and clinical studies in order to elucidate its epidemiology and to devise a more effective therapy.

Azole-resistant Aspergillus fumigatus with the environmental TR46/Y121F/T289A mutation in India.

resistant A. fumigatus strains originated from Varanasi, five from a potato (Solanum tuberosum) field and one from a fenugreek (Trigonella foenum-graecum) field, which were located 2 km apart from each other. Four of the eight itraconazole-resistant A. fumigatus strains originated from rose (Rosa species) bed soil and red chilli (Capsicum annuum) fields, Delhi. Of the remaining four itraconazole-resistant A. fumigatus strains, one each originated from fields of aubergine (Solanum melongena), mustard (Brassica juncea), potato and fenugreek in Varanasi. Notably, 5.7% of the soil samples harboured voriconazole-resistant A. fumigatus and 7.6% harboured itraconazole-resistant A. fumigatus. The overall isolation rate of both itraconazole- and voriconazole-resistant A. fumigatus was found to be higher in Varanasi (26.3%; 10/38) than in Delhi (4.5%; 4/88). Identification of resistant A. fumigatus strains was confirmed by sequencing of the internal transcribed spacer region,

Schizophyllum commune as an emerging fungal pathogen: a review and report of two cases.

We report Schizophyllum commune as the aetiological agent of one case each of allergic broncho‐pulmonary mycosis (ABPM) and pulmonary fungal ball, and present a literature review. The fungus was characterised by clamp connections, hyphal spicules, and formation of basidiocarps with basidiospores. The phenotypic identification was confirmed by sequencing of the ITS region. To‐date, ABPM and pulmonary fungal ball to S. commune have been reported exclusively from Japan and North America respectively. Of the 71 globally reported cases due to S. commune, 45 (63%) were bronchopulmonary, 22 (31%) sinusitis and 4 extrapulmonary. Taken together, cases of bronchopulmonary disease and sinusitis numbered 67 (94%), indicating the respiratory tract as the primary target of disease. Concerning the country‐wise distribution, Japan topped the list with 33 cases (46%), followed by Iran – 7 cases (10%), U.S.A. – 6 cases (9%), and a lower prevalence of 1.4–6% for the remaining 12 countries. The preponderance of the disease in Japan may be attributed to its greater awareness vis‐à‐vis that in other countries rather than to any geographical/climatic factors. We believe that the burden of S. commune‐incited disease is currently underestimated, warranting comprehensive prospective studies to determine its prevalence.