Non-dermatophyte moulds as skin and nail foot mycosis agents: Phoma herbarum, Chaetomium globosum and Microascus cinereus

First report of chronic invasive fungal rhinosinusitis in a patient with ovarian cancer caused by Didymella pedeiae and successful treatment with voriconazole: A case report

Background and Purpose:

Didymella pedeiae is a dematiaceous fungus that belongs to the Coelomycetes class. While species within this class are known to cause human infection,  D. pedeiae had previously only been known as phytopathogens and had never been isolated from a human sample.

Case report:

A 51-year-old Iranian female patient with ovarian cancer was admitted with unilateral lesions in paranasal sinuses and a five-month history of nasal obstruction, headache, postnasal drainage, swelling on the left side of the face, and orbital pain. Paranasal sinus computerized tomography scan revealed a soft tissue mass that filled the left nasal cavity, ethmoid, sphenoid, and frontal sinuses with more involvement in the maxillary and ethmoid sinuses. Antifungal treatment was simultaneously initiated with itraconazole+prednisolone 15 mg/day, and levofloxacin. Due to poor clinical response, IV voriconazole and amphotericin B were added to the treatment as well. The patient recovered completely after 10 weeks of therapy.

Conclusion:

Here, we report the first case of human D. pedeiae infection in a patient with ovarian cancer.

Superficial mycoses, a matter of concern: Global and Indian scenario-an updated analysis

Superficial mycoses of skin, nails and hair are among the common fungal infections. They are caused by dermatophytes, non-dermatophyte moulds, yeasts and yeast-like fungi. Such fungal infections are widespread all over the world and are predominant in tropical as well as subtropical regions. Environmental factors, such as warm, humid and pitiable hygienic conditions, are conducive for their growth and proliferation. Although it does not cause mortality, it is known to be associated with excessive morbidity which may be psychological or physical. This affects the quality of life of the infected individuals which leads to a negative impact on their occupational, emotional and social status. Such infections are increasing on a global scale and, therefore, are of serious concern worldwide. This review article covers the global and Indian scenario of superficial mycoses taking into account the historical background, aetiological agents, prevalence, cultural and environmental factors, risk factors, pathogenesis and hygienic practices for the prevention of superficial mycoses.

Swim bladder mycosis in farmed rainbow trout Oncorhynchus mykiss caused by Phoma herbarum and experimental verification of pathogenicity

In this study, spontaneous swim bladder mycosis was documented in a farmed fingerling rainbow trout from a raceway culture system. At necropsy, the gross lesions included a thickened swim bladder wall, and the posterior portion of the swim bladder was enlarged due to massive hyperplasia of muscle. A microscopic wet mount examination of the swim bladder contents revealed abundant septate hyphae, and histopathological examination showed periodic acid-Schiff-positive mycelia in the lumen and wall of the swim bladder. Histopathological examination of the thickened posterior swim bladder revealed muscle hyperplasia with expansion by inflammatory cells. The causative agent was identified as Phoma herbarum through morphological analysis and DNA sequencing. The disease was reproduced in rainbow trout fingerlings using intraperitoneal injection of a spore suspension. Necropsy in dead and moribund fish revealed extensive congestion and haemorrhages in the serosa of visceral organs and in liver and abdominal serosanguinous fluid. Histopathological examination showed severe hepatic congestion, sinusoidal dilatation, Kupffer cell reactivity, leukostasis and degenerative changes. Fungi were disseminated to the liver, pyloric caeca, kidney, spleen and heart. Although infections caused by Phoma spp. have been repeatedly reported in fish, species identification has been hampered by extensive taxonomic changes. The results of this study confirmed the pathogenicity of P. herbarum in salmonids by using a reliably identified strain during experimental fish infection and provides new knowledge regarding the course of infection.

Citizen science project reveals high diversity in Didymellaceae (Pleosporales, Dothideomycetes)

Fungal communities play a crucial role in maintaining the health of managed and natural soil environments, which directly or indirectly affect the properties of plants and other soil inhabitants. As part of a Citizen Science Project initiated by the Westerdijk Fungal Biodiversity Institute and the Utrecht University Museum, which aimed to describe novel fungal species from Dutch garden soil, the diversity of Didymellaceae, which is one of the largest families in the Dothideomycetes was investigated. A preliminary analysis of the ITS and LSU sequences from the obtained isolates allowed the identification of 148 strains belonging to the family. Based on a multi-locus phylogeny of a combined ITS, LSU, rpb2 and tub2 alignment, and morphological characteristics, 20 different species were identified in nine genera, namely Ascochyta, Calophoma, Didymella, Juxtiphoma, Nothophoma, Paraboeremia, Phomatodes, Stagonosporopsis, and Xenodidymella. Several isolates confirmed to be ubiquitous plant pathogens or endophytes were for the first time identified from soil, such as Ascochyta syringae, Calophoma clematidis-rectae, and Paraboeremia litseae. Furthermore, one new genus and 12 novel species were described from soil: Ascochyta benningiorum sp. nov., Didymella degraaffiae sp. nov., D. kooimaniorum sp. nov., Juxtiphoma kolkmaniorum sp. nov., Nothophoma brennandiae sp. nov., Paraboeremia rekkeri sp. nov., P. truiniorum sp. nov., Stagonosporopsis stuijvenbergii sp. nov., S. weymaniae sp. nov., Vandijckomycella joseae gen. nov. et sp. nov., V. snoekiae sp. nov., and Xenodidymella weymaniae sp. nov. From the results of this study, soil was revealed to be a rich substrate for members of Didymellaceae, several of which were previously known only from diseased or apparently healthy plant hosts.

An unusual case of Microascus brain abscess in an immunocompetent child and a review of the literature

We present a case of brain abscess in an immunocompetent child due to the dematiaceous fungus Microascus cinereus, an organism commonly found in soil and stored grains. The etiologic agent was demonstrated by direct microscopy and culture. The patient responded well to surgical excision of abscess along with a course of amphotericin B and voriconazole. Microascus species have emerged as significant invasive pathogens especially in the immunocompromised patients. To the best of our knowledge, this is the first reported case of brain abscess caused by M. cinereus in an immunocompetent individual with no underlying risk factors.

Biological properties of Phoma macrostoma related to non-dermatophyte onychomycosis

We report a rare case of non-dermatophytic onychomycosis of the toenail caused by Phoma macrostoma. Was studied the biological properties of the strain isolated in Kazakhstan. P. macrostoma forms pink colonies, the reverzum is pink-orange. The mycelium is colorless, septate. The appearance of growth tubes from pycnidospores occurs within 12 hours, mycelial growth and branching after 18 hours, the appearance of pycnids is 48 hours. The saccharolytic and urease activity of the strain is low.

PM2.5 from a broiler breeding production system: The characteristics and microbial community analysis

Particulate matter (PM) released from the processes of livestock production has a negative impact on the health of animals and workers. Herein, the concentration, major chemical components, morphology and microbiological compositions of particulate matter 2.5 (PM_2.5, particles with aerodynamic diameter less than 2.5 μm) in a broiler breeding house were investigated. The results showed that the PM_2.5 distribution in the chicken house was affected by the illumination, draught fans, chicken frame structure and activity of the chickens in the broiler breeding house. Component analysis showed that organic carbon (OC) accounted for the largest proportion, and followed by element carbon (EC), SO₄^2-, NO₃^-, NH₄⁺, Na⁺, K⁺ and Ca²⁺. Ultrastructural observations revealed that the shape of PM_2.5 had a round, rectangular, chain-like and irregular shape. The concentration of endotoxin was approximately 0.3 EU/m³. Microbiological analysis showed that at the genus level, the pathogenic bacteria included Staphylococcus, Corynebacterium, Enterococcus, Parabacteroides, Escherichia and Megamonas. The abundant harmful fungi were Aspergillus, Scopulariopsis, Wallemia, and Fusarium. Through redundancy analysis (RDA) analysis, we determined that OC, EC, Na⁺, K⁺, and NH₄⁺ had strong correlations with Brachybacterium, Brevibacterium, Corynebacterium, Escherichia, Scopulariopsis and Microascus. SO₄^2- was closely related to Scopulariopsis and Salinicoccus. Salinicoccus was also strongly correlated with NO₃^-. Our results indicated that feed, faeces, and outside soot are contributed to the increase in PM_2.5 concentration in the chicken house, while the sources of the dominant bacterial and fungi might be feed, faeces, suspended outside soil and cereal crops.

Diversity of phenotypically non-dermatophyte, non-Aspergillus filamentous fungi causing nail infections: importance of accurate identification and antifungal susceptibility testing

Onychomycosis is most commonly caused by dermatophytes. In this study, we examined the spectrum of phenotypically non-dermatophyte and non-Aspergillus fungal isolates recovered over a 10-year period from nails of patients with onychomycosis in Hong Kong. A total of 24 non-duplicated isolates recovered from 24 patients were included. The median age of the patients was 51 years, and two-thirds of them were males. One-third and two-thirds had finger and toe nail infections respectively. Among these 24 nail isolates, 17 were confidently identified as 13 different known fungal species, using a polyphasic approach. These 13 species belonged to 11 genera and ≥9 families. For the remaining seven isolates, multilocus sequencing did not reveal their definite species identities. These seven potentially novel species belonged to four different known and three potentially novel genera of seven families. 33.3%, 41.7% and 95.8% of the 24 fungal isolates possessed minimum inhibitory concentrations of >1 µg/mL to terbinafine, itraconazole and fluconazole, respectively, the first line treatment of onychomycosis. A high diversity of moulds was associated with onychomycosis. A significant proportion of the isolates were potentially novel fungal species. To guide proper treatment, molecular identification and antifungal susceptibility testing should be performed for these uncommonly isolated fungal species.

A human subcutaneous infection by Microascus ennothomasiorum sp. nov

A 60-year-old woman presented with a nodular granulomatous skin lesion on her right thumb. It had developed after inoculation of a splinter of wood. Because it was resistant to various therapies, the nodule was finally excised. Complete healing followed this surgery and a melanised filamentous fungus with scopulariopsis-like morphology was recovered from the dermal tissue. Fitting with no known species, the fungus was subjected to extensive morphological, physiological and genetic investigations. It was characterised by resistance to cycloheximide, growth at 37°C, branched conidiophores with cylindrical annellides in brush-like groups producing dark conidia in basipetal chains, and cleistothecia with ellipsoidal to slightly reniform ascospores. Genetically it clustered in a well-supported clade together with Microascus (M.) brunneosporus, Microascus chinensis, Microascus intricatus, Microascus longicollis, Microascus micronesiensis and Microascus onychoides, but formed an independent branch distant from the other Microascus species. Based on its unique genetic characteristics and morphological findings, the isolate is proposed as a new species, Microascus ennothomasiorum. Morphologically it differs from its phylogenetically closest species by its branched conidiophores and ascomata with a peridium of textura intricata. Our observation once again emphasises that dermal granulomas can be caused by uncommon fungi; diagnostics should therefore include appropriate mycological investigations.

Phoma Infections: Classification, Potential Food Sources, and Its Clinical Impact

Phoma species are phytopathogens that are widely distributed in the environment, most commonly found in aquatic systems and soil. Phoma spp. have the potential to be pathogenic in plants, animals and humans; the latter is a rare occurrence. However, as our immunocompromised population increases, so do the reports of these infections. Medical advances have allowed for the increase in solid organ transplantation; chemotherapies to treat malignancies; and the use of other immunosuppressive agents, which have resulted in a greater population at risk when exposed to diverse fungi including Phoma spp. These fungi have been isolated from water sources, food, and crops; thus acting as opportunistic pathogens when the right host is exposed. Phoma spp. contaminates common food sources such as potatoes and maize, a common species isolated being Phoma sorghina. Though there is potential for causing infection via consumption of contaminated foods, there is insufficient data detailing what levels of organism can lead to an infection, and a regulated process for detecting the organism. The spectrum of disease is wide, depending on the host, ranging from cutaneous infections to invasive diseases. Mortality, however, remains low.

Diversity and taxonomy of Chaetomium and chaetomium-like fungi from indoor environments

During a study of indoor fungi, 145 isolates belonging to Chaetomiaceae were cultured from air, swab and dust samples from 19 countries. Based on the phylogenetic analyses of DNA-directed RNA polymerase II second largest subunit (rpb2), β-tubulin (tub2), ITS and 28S large subunit (LSU) nrDNA sequences, together with morphological comparisons with related genera and species, 30 indoor taxa are recognised, of which 22 represent known species, seven are described as new, and one remains to be identified to species level. In our collection, 69 % of the indoor isolates with six species cluster with members of the Chaetomium globosum species complex, representing Chaetomium sensu stricto. The other indoor species fall into nine lineages that are separated from each other with several known chaetomiaceous genera occurring among them. No generic names are available for five of those lineages, and the following new genera are introduced here: Amesia with three indoor species, Arcopilus with one indoor species, Collariella with four indoor species, Dichotomopilus with seven indoor species and Ovatospora with two indoor species. The generic concept of Botryotrichum is expanded to include Emilmuelleria and the chaetomium-like species B. muromum (= Ch. murorum) in which two indoor species are included. The generic concept of Subramaniula is expanded to include several chaetomium-like taxa as well as one indoor species. Humicola is recognised as a distinct genus including two indoor taxa. According to this study, Ch. globosum is the most abundant Chaetomiaceae indoor species (74/145), followed by Ch. cochliodes (17/145), Ch. elatum (6/145) and B. piluliferum (5/145). The morphological diversity of indoor Chaetomiaceae as well as the morphological characteristics of the new genera are described and illustrated. This taxonomic study redefines the generic concept of Chaetomium and provides new insight into the phylogenetic relationships among different genera within Chaetomiaceae.

Coelomycetous Fungi in the Clinical Setting: Morphological Convergence and Cryptic Diversity

Human infections by coelomycetous fungi are becoming more frequent and range from superficial to systemic dissemination. Traumatic implantation of contaminated plant material is the most common cause. The typical morphological feature of these fungi is the production of asexual spores (conidia) within fruiting bodies called conidiomata. This study aimed to determine the distribution of the coelomycetes in clinical samples by a phenotypic and molecular study of a large set of isolates received from a U.S. reference mycological institution and by obtaining the in vitro antifungal susceptibility pattern of nine antifungals against a selected group of isolates. A total of 230 isolates were identified by sequencing the D1 and D2 domains of the large subunit (LSU) nuclear ribosomal RNA (nrRNA) gene and by morphological characterization. Eleven orders of the phylum Ascomycota were identified: Pleosporales (the largest group; 66.1%), Botryosphaeriales (19.57%), Glomerellales (4.35%), Diaporthales (3.48%), Xylariales (2.17%), Hysteriales and Valsariales (0.87%), and Capnodiales, Helotiales, Hypocreales and Magnaporthales (0.43% each). The most prevalent species were Neoscytalidium dimidiatum, Paraconiothyrium spp., Phoma herbarum, Didymella heteroderae, and Epicoccum sorghinum The most common anatomical site of isolation was superficial tissue (66.5%), followed by the respiratory tract (17.4%). Most of the isolates tested were susceptible to the majority of antifungals, and only flucytosine showed poor antifungal activity.

Isolation and Characterization of an Atypical Metschnikowia sp. Strain from the Skin Scraping of a Dermatitis Patient

A yeast-like organism was isolated from the skin scraping sample of a stasis dermatitis patient in the Mycology Unit Department of Medical Microbiology, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia. The isolate produced no pigment and was not identifiable using chromogenic agar and API 20C AUX. The fungus was identified as Metschnikowia sp. strain UM 1034, which is close to that of Metschnikowia drosophilae based on ITS- and D1/D2 domain-based phylogenetic analysis. However, the physiology of the strain was not associated to M. drosophilae. This pathogen exhibited low sensitivity to all tested azoles, echinocandins, 5-flucytosine and amphotericin B. This study provided insight into Metschnikowia sp. strain UM 1034 phenotype profiles using a Biolog phenotypic microarray (PM). The isolate utilized 373 nutrients of 760 nutrient sources and could adapt to a broad range of osmotic and pH environments. To our knowledge, this is the first report of the isolation of Metschnikowia non-pulcherrima sp. from skin scraping, revealing this rare yeast species as a potential human pathogen that may be misidentified as Candida sp. using conventional methods. Metschnikowia sp. strain UM 1034 can survive in flexible and diverse environments with a generalist lifestyle.

Determining the Pathogenic Potential of Non-sporulating Molds Isolated from Cutaneous Specimens

Although non-sporulating molds (NSM) are frequently isolated from patients and have been recognized as agents of pulmonary disease, their clinical significance in cutaneous specimens is relatively unknown. Therefore, this study aimed to identify NSM and to determine the keratinolytic activity of isolates from cutaneous sites. NSM isolates from clinical specimens such as skin, nail, and body fluids were identified based on their ribosomal DNA sequences. Of 17 NSM isolates (7 Ascomycota, 10 Basidiomycota), eleven were identified to species level while five were identified to the genus level. These include Schizophyllum commune, a known human pathogen, Phoma multirostrata, a plant pathogen, and Perenniporia tephropora, a saprophyte. To determine fungal pathogenicity, keratinolytic activity, a major virulence factor, was evaluated ex vivo using human nail samples by measuring dye release from keratin azure, for NSM along with pathogens (Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis and Fusarium spp.) and nonpathogenic (endophyte) fungi for comparison. This study showed that pathogenic fungi had the highest keratinolytic activity (7.13 ± 0.552 keratinase units) while the nonpathogenic endophytes had the lowest activity (2.37 ± 0.262 keratinase units). Keratinolytic activity of two Ascomycota NSM (Guignardia mangiferae and Hypoxylon sp.) and one Basidiomycota NSM (Fomitopsis cf. meliae) was equivalent to that of pathogenic fungi, while Xylaria feejeensis showed significantly higher activity (p < 0.05) than nonpathogenic endophytes. These results indicate that the pathogenic ability of NSM is species dependent; clinical isolates, especially more frequently isolated species, may be involved in disease etiology.

Phylogenetic reassessment of the Chaetomium globosum species complex

Chaetomium globosum, the type species of the genus, is ubiquitous, occurring on a wide variety of substrates, in air and in marine environments. This species is recognised as a cellulolytic and/or endophytic fungus. It is also known as a source of secondary metabolites with various biological activities, having great potential in the agricultural, medicinal and industrial fields. On the negative side, C. globosum has been reported as an air contaminant causing adverse health effects and as causal agent of human fungal infections. However, the taxonomic status of C. globosum is still poorly understood. The contemporary species concept for this fungus includes a broadly defined morphological diversity as well as a large number of synonymies with limited phylogenetic evidence. The aim of this study is, therefore, to resolve the phylogenetic limits of C. globosum s.str. and related species. Screening of isolates in the collections of the CBS-KNAW Fungal Biodiversity Centre (The Netherlands) and the China General Microbiological Culture Collection Centre (China) resulted in recognising 80 representative isolates of the C. globosum species complex. Thirty-six species are identified based on phylogenetic inference of six loci, supported by typical morphological characters, mainly ascospore shape. Of these, 12 species are newly described here. Additionally, C. cruentum, C. mollipilium, C. rectum, C. subterraneum and two varieties of C. globosum are synonymised under C. globosum s.str., and six species are resurrected, i.e. C. angustispirale, C. coarctatum, C. cochliodes, C. olivaceum, C. spiculipilium and C. subglobosum. Chaetomium ascotrichoides is segregated from C. madrasense and the genus name Chaetomidium is rejected. Five species, including C. globosum s.str., are typified here to stabilise their taxonomic status. A further evaluation of the six loci used in this study as potential barcodes indicated that the 28S large subunit (LSU) nrDNA and the internal transcribed spacer regions and intervening 5.8S nrRNA (ITS) gene regions were unreliable to resolve species, whereas β-tubulin (tub2) and RNA polymerase II second largest subunit (rpb2) showed the greatest promise as DNA barcodes for differentiating Chaetomium species. This study provides a starting point to establish a more robust classification system for Chaetomium and for the Chaetomiaceae.

Black Molds and Melanized Yeasts Pathogenic to Humans

A review is given of melanized fungi involved in human infection, including species forming budding cells and strictly filamentous representatives. Classically, they are known as "phaeoid" or "dematiaceous" fungi, and, today, agents are recognized to belong to seven orders of fungi, of which the Chaetothyriales and Pleosporales are the most important. Infections range from cutaneous or pulmonary colonization to systemic or disseminated invasion. Subcutaneous involvement, either primary or after dissemination, may lead to host tissue proliferation of dermis or epidermis. Particularly in the Chaetothyriales, subcutaneous and systemic infections may occur in otherwise apparently healthy individuals. Infections are mostly chronic and require extended antifungal therapy and/or surgery.

Advances in taxonomy of genus phoma: polyphyletic nature and role of phenotypic traits and molecular systematics

Phoma is a highly polyphyletic genus with its unclear species boundaries. The conventional system of identification is functional but it has its limitations. Besides morphological studies, chemotaxonomy, secondary metabolite and protein profiling have been assessed for the classification and identification of these fungi. Molecular datasets have provided a better outlook towards the phylogenetic and evolutionary trends of Phoma. Molecular markers such as ITS-rDNA, tubulin, actin, translation elongation factor have been widely used by the taxonomists to demarcate species. However, outcomes gained up till now represent preliminary step towards the study of Phoma systematics and a combined approach would be beneficial in the understanding of this polyphyletic group members. Lately, on the base of molecular phylogeny of the type species of the seven Phoma sections a new teleomorph family, Didymellaceae has been established, besides the Phaeosphaeriaceae related to sect. Paraphoma anamorphs, and the Leptosphaeriaceae to sect. Heterospora anamorphs. The estimated ratio is about 70 % of the recognized Phoma-like species can be associated with the Didymellaceae ascomycetous family.

Onychomycosis Caused by Chaetomium globosum

Onychomycosis is usually caused by dermatophytes, but some nondermatophytic molds and yeasts are also associated with invasion of nails. The genus Chaetomium is a dematiaceous nondermatophytic mold found in soil and plant debris as a saprophytic fungus. We report the first Korean case of onychomycosis caused by Chaetomium globosum in a 35-year-old male. The patient showed brownish-yellow discoloration and subungual hyperkeratosis on the right toenails (1st and 5th) and left toenails (1st and 4th). Direct microscopic examination of scraping on the potassium hydroxide preparation revealed septate hyphae and repeated cultures on Sabouraud's dextrose agar (SDA) without cycloheximide slants showed the same fast-growing colonies, which were initially velvety white then turned to dark gray to brown. However, there was no growth of colony on SDA with cycloheximide slants. Brown-colored septated hyphae, perithecia and ascospores were shown in the slide culture. The DNA sequence of internal transcribed spacer region of the clinical sample was a 100% match to that of C. globosum strain ATCC 6205 (GenBank accession number EF524036.1). We confirmed C. globosum by KOH mount, colony, and light microscopic morphology and DNA sequence analysis. The patient was treated with 250 mg oral terbinafine daily and topical amorolfine 5% nail lacquer for 3 months.

Phoma and Acremonium invasive fungal rhinosinusitis in congenital acute lymphocytic leukemia and literature review

OBJECTIVE

Invasive rhinocerebral fungal infections are a difficult and often fatal problem in children with hematologic malignancies, with increasing reports of rare pathogens. We describe a case of congenital acute lymphoblastic leukemia (ALL) and invasive fungal rhinosinusitis involving Acremonium and Phoma species, not previously reported in invasive pediatric fungal rhinosinusitis, and review all published cases of human Phoma infections.

METHODS

A literature and institutional review for Phoma spp. was completed including patient demographics, infection site, immune status, treatment and outcome.

RESULTS

A female neonate with acute lymphoblastic leukemia presented with hyperleukocytosis and advanced invasive Phoma and Acremonium spp. rhinosinusitis. Despite aggressive medical and surgical therapy, the disease progressed to a rhinocerebral infection with a fatal outcome. Twenty cases of Phoma spp. were found in a complete literature search, including 6 females and 14 males from 18 months to 77 years old. Infections were superficial in fifteen patients and involved deeper tissue in five patients, with sites including cutaneous, subcutaneous and deep tissue sites (eye, lung, extremity deep tissue compartments).

CONCLUSIONS

This case highlights the risks and grave prognosis of fulminant invasive fungal rhinosinusitis in the context of congenital leukemia, and the potential for rare fungal species in neonates with immunosuppression.

Phaeohyphomycosis and onychomycosis due to Chaetomium spp., including the first report of Chaetomium brasiliense infection

Chaetomium species have been rarely described as aetiological agents of invasive and dermatomycotic infections in humans. The majority of cases have been reported within the last two decades. Treatment failed in most of these cases. In this paper we present two cases in which Chaetomium spp. can be clearly identified as an aetiological agent in pathological conditions. In the first report, we describe a new aetiological agent, Chaetomium brasiliense, which was implicated in a case of otitis externa in a patient with spinocellular carcinoma basis cranii. The patient had been repeatedly treated for relapsing otitis externa and had previously undergone surgery several times for otitis media. The fungal aetiology was confirmed by repeated positive culture and histologic studies. The second case involved onychomycosis with strikingly brown nail discoloration due to Chaetomium globosum in an otherwise healthy patient. The nail lesion was successfully cured by oral terbinafine. The determination of both species was supported by sequencing of rDNA regions. The morphological aspect of Chaetomium spp. identification is also discussed. In vitro antifungal susceptibility tests demonstrated that both isolates were susceptible to terbinafine and azole derivates except fluconazole. Amphotericin B was effective only against the C. brasiliense strain. We review the literature to summarize clinical presentations, histologic findings, and treatment strategies.