Cutaneous infection with Metarhizium anisopliae in a patient with hypohidrotic ectodermal dysplasia and immune deficiency

Revisiting Metarhizium and the description of new species from Thailand

Over the last two decades the molecular phylogeny and classification of Metarhizium has been widely studied. Despite these efforts to understand this enigmatic genus, the basal lineages in Metarhizium are still poorly resolved. In this study, a phylogenetic framework is reconstructed for the Clavicipitaceae focusing on Metarhizium through increased taxon-sampling using five genomic loci (SSU, LSU, tef, rpb1, rpb2) and the barcode marker ITS rDNA. Multi-gene phylogenetic analyses and morphological characterisation of green-spored entomopathogenic Metarhizium isolates from Thailand and soil isolates of M. carneum and M. marquandii reveal their ecological, genetic and species diversity. Nineteen new species are recognised in the Metarhizium clade with narrow host ranges: two new species are found in the M. anisopliae complex - M. clavatum on Coleoptera larvae and M. sulphureum on Lepidoptera larvae; four new species are found in the M. flavoviride complex - M. biotecense and M. fusoideum on brown plant hoppers (Hemiptera), M. culicidarum on mosquitoes, M. nornnoi on Lepidoptera larvae; three new species M. megapomponiae, M. cicadae, M. niveum occur on cicadas; five new species M. candelabrum, M. cercopidarum, M. ellipsoideum, M. huainamdangense M. ovoidosporum occur on planthoppers, leafhoppers and froghoppers (Hemiptera); one new species M. eburneum on Lepidoptera pupae; and four new species M. phuwiangense, M. purpureum, M. purpureonigrum, M. flavum on Coleoptera . Of these 19 new species, seven produce a sexual morph (M. clavatum, M. eburneum, M. flavum, M. phuwiangense, M. purpureonigrum, M. purpureum, and M. sulphureum) and asexual morphs are found in the remaining new species and also in M. sulphureum, M. purpureonigrum and M. purpureum. Metarhizium blattodeae, M. koreanum and M. viridulum are new records for Thailand. An alternative neotype for Metarhizium anisopliae is proposed based on multi-gene and 5'tef analyses showing that CBS 130.71 from Ukraine is more suitable, being from a much closer geographical location to Metchnikoff's Metarhizium anisopliae. This isolate is distinct from the neotype of Metarhizium anisopliae var. anisopliae proposed by M. Tulloch from Ethiopia (ARSEF 7487). Six new genera are established for monophyletic clades subtending the core Metarhizium clade, including Keithomyces, Marquandomyces, Papiliomyces, Purpureomyces, Sungia, and Yosiokobayasia. Metarhizium carneum, M. aciculare, and M. neogunnii are combined in Keithomyces and one new combination for M. marquandii in Marquandomyces is proposed. Purpureomyces is introduced for species producing purple stromata including a new combination for M. khaoyaiense and two new species P. maesotensis and P. pyriformis. Papiliomyces contains two new combinations for M. liangshanense and Metacordyceps shibinensis. The genus Sungia is proposed for the Korean species M. yongmunense on Lepidoptera pupa and Yosiokobayasia for the Japanese species M. kusanagiense also on Lepidoptera pupa. A synoptic and dichotomous key to the accepted taxa is provided together with tables listing distinguishing morphological characters between species, host preferences, and geography.

Multi-locus sequence typing provides epidemiological insights for diseased sharks infected with fungi belonging to the Fusarium solani species complex

Fusarium spp. are saprobic moulds that are responsible for severe opportunistic infections in humans and animals. However, we need epidemiological tools to reliably trace the circulation of such fungal strains within medical or veterinary facilities, to recognize environmental contaminations that might lead to infection and to improve our understanding of factors responsible for the onset of outbreaks. In this study, we used molecular genotyping to investigate clustered cases of Fusarium solani species complex (FSSC) infection that occurred in eight Sphyrnidae sharks under managed care at a public aquarium. Genetic relationships between fungal strains were determined by multi-locus sequence typing (MLST) analysis based on DNA sequencing at five loci, followed by comparison with sequences of 50 epidemiologically unrelated FSSC strains. Our genotyping approach revealed that F. keratoplasticum and F. solani haplotype 9x were most commonly isolated. In one case, the infection proved to be with another Hypocrealian rare opportunistic pathogen Metarhizium robertsii. Twice, sharks proved to be infected with FSSC strains with the same MLST sequence type, supporting the hypothesis the hypothesis that common environmental populations of fungi existed for these sharks and would suggest the longtime persistence of the two clonal strains within the environment, perhaps in holding pools and life support systems of the aquarium. This study highlights how molecular tools like MLST can be used to investigate outbreaks of microbiological disease. This work reinforces the need for regular controls of water quality to reduce microbiological contamination due to waterborne microorganisms.

Two cases of fungal keratitis caused by Metarhizium anisopliae

We present two cases of keratitis due to Metarhizium anisopliae in geographically separated areas of the United States. The isolates were microscopically similar but morphologically different and were identified by ribosomal DNA sequencing. Both isolates had low minimum inhibitory concentration (MIC) values to caspofungin and micafungin, but high MIC values to amphotericin B. The morphologic and antifungal susceptibility differences between the two isolates indicate possible polyphylogeny of the group.

Species of the Metarhizium anisopliae complex with diverse ecological niches display different susceptibilities to antifungal agents

Species of the Metarhizium anisopliae complex are globally ubiquitous soil-inhabiting and predominantly insect-pathogenic fungi. The Metarhizium genus contains species ranging from specialists, such as Metarhizium acridum that only infects acridids, to generalists, such as M. anisopliae, Metarhizium brunneum, and Metarhizium robertsii that infect a broad range of insects and can also colonize plant roots. There is little information available about the susceptibility of Metarhizium species to clinical and non-clinical antifungal agents. We determined the susceptibility of 16 isolates comprising four Metarhizium species with different ecological niches to seven clinical (amphotericin B, ciclopirox olamine, fluconazole, griseofulvin, itraconazole, tebinafine, and voriconazole) and one non-clinical (benomyl) antifungal agents. All isolates of the specialist M. acridum were clearly more susceptible to most antifungals than the isolates of the generalists M. anisopliae sensu lato, M. brunneum, and M. robertsii. All isolates of M. anisopliae, M. brunneum, and M. robertsii were resistant to fluconazole and some were also resistant to amphotericin B. The marked differences in susceptibility between the specialist M. acridum and the generalist Metarhizium species suggest that this characteristic is associated with their different ecological niches, and may assist in devising rational antifungal treatments for the rare cases of mycoses caused by Metarhizium species.

Hematopoietic stem cell transplantation in 29 patients hemizygous for hypomorphic IKBKG/NEMO mutations

X-linked recessive ectodermal dysplasia with immunodeficiency is a rare primary immunodeficiency caused by hypomorphic mutations of the IKBKG gene encoding the nuclear factor κB essential modulator (NEMO) protein. This condition displays enormous allelic, immunological, and clinical heterogeneity, and therapeutic decisions are difficult because NEMO operates in both hematopoietic and nonhematopoietic cells. Hematopoietic stem cell transplantation (HSCT) is potentially life-saving, but the small number of case reports available suggests it has been reserved for only the most severe cases. Here, we report the health status before HSCT, transplantation outcome, and clinical follow-up for a series of 29 patients from unrelated kindreds from 11 countries. Between them, these patients carry 23 different hypomorphic IKBKG mutations. HSCT was performed from HLA-identical related donors (n = 7), HLA-matched unrelated donors (n = 12), HLA-mismatched unrelated donors (n = 8), and HLA-haploidentical related donors (n = 2). Engraftment was documented in 24 patients, and graft-versus-host disease in 13 patients. Up to 7 patients died 0.2 to 12 months after HSCT. The global survival rate after HSCT among NEMO-deficient children was 74% at a median follow-up after HSCT of 57 months (range, 4-108 months). Preexisting mycobacterial infection and colitis were associated with poor HSCT outcome. The underlying mutation does not appear to have any influence, as patients with the same mutation had different outcomes. Transplantation did not appear to cure colitis, possibly as a result of cell-intrinsic disorders of the epithelial barrier. Overall, HSCT can cure most clinical features of patients with a variety of IKBKG mutations.

Species of Metarhizium anisopliae complex implicated in human infections: retrospective sequencing study

OBJECTIVES

Fungi belonging to the Metarhizium anisopliae complex comprise ubiquitous arthropod pathogenic moulds used as mycopesticides. Rare cases of human infections due to M. anisopliae have been reported. We hypothesize misidentifications of fungal strains implicated in these cases or used in mycopesticides.

METHODS

A review of the literature was conducted to identify previously published cases. We collected some of these previous described strains and reported new cases, and a French mycopesticide containing M. anisopliae. All identifications were performed based on elongation factor-1α gene sequencing.

RESULTS

We report eight new cases of Metarhizium infection in humans (three from France and five from Australia). The strains isolated from these cases, and three others from already published cases and reported as M. anisopliae, were molecularly identified based on elongation factor-1α (Ef1-α) gene sequencing as follows: Metarhizium robertsii (six), Metarhizium guizhouense (three), Metarhizium brunneum (one) and Metarhizium pingshaense (one).

CONCLUSIONS

In this study, we report new human cases of Metarhizium infections, and, based on Ef-1α gene sequencing, we demonstrate the misidentification of species in case reports. We also correct the species identification of a strain reported as M. anisopliae used in a commercially available mycopesticide. According to our results, none of the strains from the human infection reports reviewed belongs to the species M. anisopliae.

First unusual case of keratitis in Europe due to the rare fungus Metarhizium anisopliae

Metarhizium anisopliae is a fungus utilized worldwide for insect-pest biocontrol. Few M. anisopliae infections have been reported previously. Here, M. anisopliae was isolated from a corneal ulcer in a healthy man. It is the first ocular case in France and Europe of this extremely rare fungus in humans.

Computed tomography of granulomatous pneumonia with oxalosis in an American alligator (Alligator mississippiensis) associated with Metarhizium anisopliae var anisopliae

An 18-yr-old, male, albino, American alligator (Alligator mississippiensis) was evaluated for decreased appetite and abnormal buoyancy. Computed tomography (CT) of the coelomic cavity showed multifocal mineral and soft tissue attenuating pulmonary masses consistent with pulmonary fungal granulomas. Additionally, multifocal areas of generalized, severe emphysema and pulmonary and pleural thickening were identified. The alligator was euthanized and necropsy revealed severe fungal pneumonia associated with oxalosis. Metarhizium anisopliae var. anisopliae was cultured from lung tissue and exhibited oxalate crystal formation in vitro. Crystals were identified as calcium oxalate monohydrate by X-ray powder defractometry. Fungal identification was based on morphology, including tissue sporulation, and DNA sequence analysis. This organism is typically thought of as an entomopathogen. Clinical signs of fungal pneumonia in nonavian reptiles are often inapparent until the disease is at an advanced stage, making antemortem diagnosis challenging. This case demonstrates the value of CT for pulmonary assessment and diagnosis of fungal pneumonia in the American alligator. Fungal infection with associated oxalosis should not be presumed to be aspergillosis.

Pediatric Metarrhizium anisopliae keratitis

Metarrhizium anisopliae (M. anisopliae) is an entomopathogenic fungus used as an agricultural pesticide in many countries, including the United States. M. anisopliae grows optimally at 25°C and is therefore considered safe to humans. We report a case of a 12-year-old girl who is a soft contact lens wearer with M. anisopliae corneal ulcer who was treated effectively with topical natamycin after identification of the organism by corneal culture. Topical amphotericin B was not effective.