Cutaneous hyalohyphomycosis caused by Paecilomyces lilacinus in an immunocompetent host successfully treated with itraconazole: case report and review

Recurrent cutaneous hyalohyphomycosis secondary to Purpureocillium lilacinum in an immunocompetent individual

Purpureocillium lilacinum, previously classified as Paecilomyces lilacinus, is a ubiquitous hyaline hyphomycete considered to be an emerging opportunistic human pathogen that is resistant to traditional antifungal agents. This case report describes what is to our knowledge the only published case of P. lilacinum recrudescence in an immunocompetent host despite initial best-practice treatment with 10 weeks of voriconazole and surgical excision.

Skin Immune Response of Immunocompetent and Immunosuppressed C57BL/6 Mice After Experimental Subcutaneous Infection Caused by Purpureocillium lilacinum

Hyalohyphomycosis is a fungal infection characterized by the presence of a hyaline mycelium in the host. It is caused by several agents, such as Purpureocillium lilacinum. Our study aimed to evaluate some cell subsets and inflammatory markers involved in the in situ immune response to subcutaneous hyalohyphomycosis by P. lilacinum in C57BL/6 murine models. The fungal isolate was inoculated in mice randomly distributed in immunocompetent/infected (CI) and immunosuppressed/infected (SI) groups. Mice were evaluated on days 1, 3, 5, and 7 after inoculation. Histopathological studies showed several lesions in the site of infection as well as the formation of multifocal and mixed inflammatory infiltrates, which differed between the CI and SI groups. This analysis also revealed conidia and hypha-like structures in subcutaneous tissues of mice of both groups. The immunohistochemical analysis showed lower percentages of macrophages and neutrophils in the SI group compared to those in the CI group. Moreover, the intensity of interleukin (IL)-1β and nitric oxide synthase 2 production by cells of immunosuppressed mice was discreet, compared to immunocompetent mice that ranged from moderate to intense over time. The quantitative interference of dexamethasone in the response to the fungus was also demonstrated. We concluded that our results can be useful not only to broaden the knowledge on P. lilacinum but also, based on this host-parasite relationship, to contribute to the understanding of the mechanisms of infection.

Recent developments in less known and multi-resistant fungal opportunists

Fungal infections have increased in recent years due to host factors, such as oncohaematological and transplant-related disorders, immunosuppressive therapy, and AIDS. Additionally, molecular and proteomic facilities have become available to identify previously unrecognizable opportunists. For these reasons, reports on less-known and recalcitrant mycoses, such as those caused by black fungi, hyaline filamentous fungi, coelomycetes, Mucorales, and non-Candida yeasts have emerged. In this review, novel taxonomy in these groups, which often are multi-resistant to one or several classes of antifungals, is discussed. Clinical presentations, diagnosis and current treatment of some major groups are summarised.

Keratomycosis due to Purpureocillium lilacinum: A case report from Sub-Himalayan region of Uttarakhand

The fungus Purpureocillium lilacinum previously known as Paceliomyces lilacinus is an emerging pathogen that can cause severe human infections including devastating oculomycosis. Treatment with traditional antifungals often fails, and the organism shows variable susceptibility to novel triazoles. We hereby report a case of keratomycosis caused by Pur. lilacinum in an immunocompetent male patient following trauma. The patient was successfully treated with voriconazole. The drug shows good activity against Pur. lilacinum and could be a promising therapeutic alternative to treat infections caused by this fungus, which generally shows resistance to conventional antifungal agents including novel triazoles.

Complexities associated with the molecular and proteomic identification of Paecilomyces species in the clinical mycology laboratory

Paecilomyces species are emerging fungal pathogens. Morphological identifications are complicated by similarities among the members of the P. variotii complex as well as to some Rasamsonia and Hamigera species. The purpose of this study was to compare matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) with molecular diagnostic standards (i.e., multilocus DNA sequencing of the internal transcribed spacer regions 1 and 2, D1/D2 regions, and part of the β-tubulin gene) for the identification of Paecilomyces spp. encountered in two clinical mycology laboratories. A total of 77 clinical isolates identified morphologically as P. variotii (n = 21), P. lilacinus (n = 52), and Paecilomyces spp. not otherwise specified (n = 4) were included. In accord with the most recent taxonomy, all P. lilacinus isolates were confirmed as Purpureocillium lilacinum by both sequencing and MALDI-TOF MS. Fungi phenotypically resembling P. variotii or Paecilomyces spp. were identified by molecular techniques as P. variotii sensu stricto (n = 12), P. formosus (n = 3), P. dactylethromorphus (n = 3), Rasamsonia argillacea (n = 4), or R. piperina (n = 1) and at the genus level as an isolate of a Hamigera sp. and a Paecilomyces sp. There was 92.2% (71/77) agreement between the molecular and proteomic methods only after supplementation of the MALDI-TOF MS database with type strains. Paecilomyces variotii-like organisms required multilocus DNA interrogations for differentiation and account for all of the fungi whose identification was missed by MALDI-TOF MS. Overall, MALDI-TOF MS was a rapid and reliable alternative to multilocus sequencing. However, significant augmentation of the commercially available database was required to reproducibly identify this group of important human pathogens.

Paecilomyces lilacinus causing debilitating sinusitis in an immunocompetent patient: a case report

Introduction

Since the discovery of the first documented case of Paecilomyces in 1963, only five cases of Paecilomyces sinusitis have been described to date and all of them have predisposing factors such as immunocompromised status or prior nasal surgery. We present the first case of Paecilomyces lilacinus sinusitis in a fit young woman with no identified predisposing factors. To the best of our knowledge, this is the first known case in the UK and in Europe.

Case presentation

A 20-year-old Iraqi woman who has lived in the UK for the past five years presented with rhinorrhea, hyposmia, and nasal obstruction. She was previously fit and well and had no significant medical history. Imaging revealed a fungal infection that was eventually revealed on cytological examination to be P. lilacinus.

Conclusions

P. lilacinus is both a difficult and important organism to identify because it has intrinsic anti-fungal resistance. In our case, the infection was severe and recurrent, and the organism demonstrated resistance to common oral anti-fungal agents. There was a delay in its diagnosis, owing to its similarity in appearance to Penicillium and a difficulty in distinguishing between the two without specialized knowledge of fungal taxonomy. In the field of otolaryngology, Paecilomyces is relatively unknown. Our intention is to raise awareness of this organism as well as to describe the challenges in its management.

A Rare Case of Fungal Maxillary Sinusitis due to Paecilomyces lilacinus in an Immunocompetent Host, Presenting as a Subcutaneous Swelling

Paecilomyces is a colonizing fungal species which usually causes keratitis, endocarditis, sinusitis, nephritis, fungemia, cutaneous, and subcutaneous infections in immunocompromised host. Very rarely, it causes similar infection in immunocompetent host without any risk factors. We report a case of maxillary sinusitis due to Paecilomyces lilacinus in a 65–year-old immunocompetent male, who presented with a subcutaneous swelling below the left eye. The lesion was excised by surgery and treated with itraconazole for 6 months based on culture and sensitivity. After 1 year of follow up, he is free of symptoms with no evidence of recurrence.

NB-002, a novel nanoemulsion with broad antifungal activity against dermatophytes, other filamentous fungi, and Candida albicans

NB-002 is an oil-in-water emulsion designed for use for the treatment of skin, hair, and nail infections. The activity of NB-002 was compared to the activities of the available antifungal drugs against the major dermatophytes responsible for cutaneous infections, Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum, and Microsporum spp., as well as 12 other genera of filamentous fungi. NB-002 consistently displayed fungicidal activity against all dermatophytes. The comparator compounds were either fungistatic or fungicidal, and for some strain-drug combinations, tolerance was observed. Assessment of the development of spontaneous resistance to NB-002 in different dermatophyte species yielded few stably resistant mutants. For filamentous nondermatophyte fungi, the MIC range varied from 0.06 to 0.5 microg/ml for Alternaria spp. to 2 to 8 microg/ml for Paecilomyes spp. NB-002 had activity against both azole-susceptible and -resistant Candida albicans yeast isolates, with MIC(90)s of 2 microg/ml, respectively, and minimum fungicidal concentrations at which 90% of isolates are inhibited of 4 and 8 microg/ml, respectively. The kinetics of the fungicidal activity of NB-002 against T. rubrum isolates were compared to those of the other antifungal drugs. NB-002 killed both mycelia and microconidia even when the fungal forms were dormant or not actively growing. Electron micrographs of mycelia and spores treated with NB-002 showed the significant disruption of the fungal structure. The in vitro broad coverage of NB-002 against filamentous fungi, dermatophytes, and C. albicans, as well as its rapid fungicidal activity, warrants further investigations to ascertain if NB-002 would be useful for the treatment of cutaneous mycoses.

Clinical manifestations, treatment and outcome of Paecilomyces lilacinus infections

The fungus Paecilomyces lilacinus is an emerging pathogen that causes severe human infections, including devastating oculomycosis. Usually, it shows low susceptibility to conventional antifungal drugs in vitro, and variable susceptibility to novel triazoles. A review of the published literature identified 119 reported cases of human infection by P. lilacinus between 1964 and 2004. Most were cases of oculomycosis (51.3%), followed by cutaneous and sub-cutaneous infections (35.3%), and a smaller group of miscellaneous infections (13.4%). Lens implantation is the most frequent predisposing factor for oculomycosis. Cutaneous and sub-cutaneous infections occur mainly in solid organ and bone marrow transplant recipients, although surgery and primary or acquired immunodeficiency are also relevant predisposing factors. Infections in apparently immunocompetent patients have also been reported. Surgical debridement combined with antifungal drug therapy, or the correction of predisposing factors, such as neutropenia, are usually required to obtain improvement. Treatment with traditional antifungal drugs often fails. Voriconazole has demonstrated good activity in both cutaneous and ocular infections in the few cases in which this drug has been used. The new triazoles ravuconazole and posaconazole show good in-vitro activity against P. lilacinus and could be promising therapeutic alternatives.

Emerging Fungi

The hyalohyphomycetes (especially Fusarium spp) have emerged as significant pathogens in severely immunocompromised patients. Human infections by Fusarium spp can be superficial or limited to single organs in otherwise healthy patients. Such infections are rare and tend to respond well to therapy. By contrast, disseminated fusarial hyalohyphomycosis affects the immunocompromised host and frequently is fatal. Successful outcome is determined by the degree of immunosuppression and the extent of the infection. These infections may be suspected clinically on the basis of a constellation of clinical and laboratory findings, which should lead to prompt therapy.

Acute oral intragastric pathogenicity and toxicity in mice of Paecilomyces fumosoroseus isolated from whiteflies

Paecilomyces fumosoroseus, monospore culture EH-506/3, isolated in Mexico from Bemisia tabaci whitefly was tested for acute oral intragastric pathogenicity and toxicity in CD-1 mice. Animals were inoculated by gavage with only one dose (10(8) conidia/animal) of viable (72 mice), heat-killed (24 mice) fungus and compared to 18 control mice. Clinical observations were done daily; mycological and histological tests were performed during necropsies at days 3, 10, 17, and 21 after the inoculation. No mice were clinically ill or died. At the end of the study, their mean weight corresponded to healthy adults. Positive fungal cultures of feces were obtained only 24 h after inoculation. Positive cultures were found in 15 out of 360 organs (liver, spleen, kidney, brain, lung) in 12 of 72 mice inoculated with viable conidia. Gross pathology exhibited splenomegaly and liver paleness in mice inoculated with viable and heat-killed fungus. Non-germinated conidia were observed in studied organs, without any pathological tissue reaction, suggesting no mycological or histopathological evidence of fungal multiplication. The fungus was able to persist, but did not cause permanent damage to the host. This study supports the non-pathogenic/toxic status of P. fumosoroseus EH-506/3 when administered intragastrically in mice.

Pulmonary mycetoma caused by an atypical isolate of Paecilomyces species in an immunocompetent individual: case report and literature review of Paecilomyces lung infections

The first case of pulmonary fungus ball caused by Paecilomyces species is reported. The diagnosis was established by isolation of the fungus in culture from specimens obtained by percutaneous transthoracic needle aspiration in an immunocompetent individual. The isolate was atypical, as it failed to produce fruiting structures on routine mycological media. Identification was achieved by sequencing polymorphisms of the internal transcriber spacer regions of the ribosomal DNA. The antifungal susceptibility profile was also determined. This report underscores the increasing importance of Paecilomyces species in human infections. Paecilomyces should be included among the etiological agents of pulmonary mycetoma.

Combination treatment of invasive fungal infections

The persistence of high morbidity and mortality from systemic fungal infections despite the availability of novel antifungals points to the need for effective treatment strategies. Treatment of invasive fungal infections is often hampered by drug toxicity, tolerability, and specificity issues, and added complications often arise due to the lack of diagnostic tests and to treatment complexities. Combination therapy has been suggested as a possible approach to improve treatment outcome. In this article, we undertake a historical review of studies of combination therapy and also focus on recent studies involving newly approved antifungal agents. The limitations surrounding antifungal combinations include nonuniform interpretation criteria, inability to predict the likelihood of clinical success, strain variability, and variations in pharmacodynamic/pharmacokinetic properties of antifungals used in combination. The issue of antagonism between polyenes and azoles is beginning to be addressed, but data regarding other drug combinations are not adequate for us to draw definite conclusions. However, recent data have identified potentially useful combinations. Standardization of assay methods and adoption of common interpretive criteria are essential to avoid discrepancies between different in vitro studies. Larger clinical trials are needed to assess whether combination therapy improves survival and treatment outcome in the most seriously debilitated patients afflicted with life-threatening fungal infections.

Cutaneous hyalohyphomycosis caused by Paecilomyces lilacinus: report of three cases and review of the literature

Cutaneous infection with Paecilomyces lilacinus is encountered worldwide, with most infections occurring either iatrogenically or in immunocompromised hosts. We report three cases of cutaneous hyalohyphomycosis caused by P. lilacinus, one of which occurred in an immunocompetent individual. In addition, we review the 17 cases previously reported in the literature. Although this infection can be difficult to treat, most cases are not fatal. Most cases responded well to systemic azole antifungal agents, either alone or in association with surgical excision of the lesion. Paecilomyces species are saprophytic fungi found in soil and decaying organic matter. Infection in humans is rare, but when it occurs treatment is often difficult. We report three cases of cutaneous hyalohyphomycosis caused by P. lilacinus and review the 17 previously reported cases in which the clinical history and response to therapy were described.

Paecilomyces lilacinus vaginitis in an immuno-competent patient

Paecilomyces lilacinus, an environmental mold found in soil and vegetation, rarely causes human infection. We report the first case of P. lilacinus isolated from a vaginal culture in a patient with vaginitis.

Cutaneous Paecilomycosis in a Cat

A cat was presented for a 2-year history of a recurrent, soft-tissue swelling of the left metacarpal region. The mass was excised and submitted for aerobic and anaerobic bacterial culture, fungal culture, and histopathological examination. Cultures revealed the organism Paecilomyces lilacinus, and histopathological examination showed a nodular mycotic granuloma. Itraconazole (10 mg/kg body weight, per os [PO], q 24 hours) was administered and continued for a total of 60 days, with a swelling of the upper lip occurring 3 months after the initial presentation. Subsequent surgical excisions and debridements along with treatment with itraconazole (20 mg/kg body weight, PO, q 24 hours) for a total of 4 months were curative.

Voriconazole treatment of disseminated paecilomyces infection in a patient with acquired immunodeficiency syndrome

We describe a patient with poorly controlled, multidrug-resistant human immunodeficiency virus disease who developed >20 skin lesions caused by Paecilomyces lilacinus. The lesions failed to improve during treatment with oral itraconazole, amphotericin B, and amphotericin B lipid complex but improved during treatment with voriconazole.

Cutaneous hyalohyphomycosis and onychomycosis caused by Onychocola canadensis: report of the first case from Turkey

We present the first Turkish case of skin and nail infection due to Onychocola canadensis in an otherwise healthy farmer who frequently worked barefoot on soil. Cutaneous involvement consisted of scaly and hyperkeratotic lesions resembling tinea pedis, erythematous plaques, and dermal papulonodules of various sizes simulating Majocchi's granuloma. Repeated cultures from nail plates, skin scrapings and needle aspiration materials from papules or nodules all yielded the same mold on Sabouroud dextrose media with and without cycloheximide, trichophyton agar, and potato dextrose agar at 26 degrees C. The causal isolate was identified as Onychocola canadensis Sigler gen. et sp. nov., a slow-growing arthroconidial hyphomycete, on the basis of its colonial and microscopic morphology. While skin lesions were responsive to daily itraconazole in a dose of 200 mg for three months, the onychomycosis was resistant to therapy. To our knowledge, this is the first presentation of O. canadensis as the cause of cutaneous hyalohyphomycosis to date.

Progressive cutaneous hyalohyphomycosis due to Paecilomyces lilacinus: rapid response to treatment with caspofungin and itraconazole

A case of rapidly progressive cutaneous infection due to Paecilomyces lilacinus developed in a woman with advanced pancreatic cancer who did not have granulocytopenia. The infection responded favorably to caspofungin and itraconazole combination therapy.

Case report. Successful treatment of cutaneous Paecilomyces lilacinus infection with oral itraconazole in an immune competent host

A 59-year-old woman presented to us with an eight-month history of Paecilomyces lilacinus soft tissue infection. She was treated with a six-month course of oral itraconazole. The lesion resolved fully without the need for adjunctive surgery. Susceptibility testing confirmed susceptibility to itraconazole. This is the second case of confirmed P. lilacinus soft tissue infection in an immunocompetent host treated with oral itraconazole alone.