Phaeohyphomycosis caused by Dactylaria (human dactylariosis): report of a case with review of the literature

Dematiaceous fungal infections in solid organ transplantation: systematic review and bayesian meta-analysis

BACKGROUND

Dematiaceous fungi cause a number of infectious syndromes referred to as phaeohyphomycosis among both immunocompetent and immunocompromised hosts. We performed a systematic review to characterize these infections in solid organ transplant recipients (SOTR).

METHODS

We searched PubMed database (last searched 1/6/2022) for English-language reports on dematiaceous fungal infections in SOTR. Included reports needed individualized demographic, treatment, and outcome data; pediatric reports were excluded. A universally applicable bias assessment was performed on reports. Models for infection type and outcome were created using the Bayesian paradigm.

RESULTS

We included 149 reports on 201 cases of dematiaceous fungal infections in SOTR. The mean age was 54 years, 72% were men, and kidney recipients accounted for 61% of cases. Skin and soft tissue infection (SSTI) was the most common infectious syndrome (73%). Death from infection occurred in 7% of cases (14/201), with disseminated (32%) cases having the highest mortality. Our model for infection type predicted the relative probability of central nervous system infection to be highest in liver recipients. Across all transplant types, higher relative probabilities of disseminated and pulmonary infections occur in the early post-transplant period, and the predicted probabilities for these infection types decreased after 100 months post-transplantation.

DISCUSSION

We identified SSTI as the most common dematiaceous fungal infections in SOTR. Disseminated infections carried the worst prognosis. The evidence in this review is limited by the heterogeneity of included cases. No funding source was used, and this review's protocol was not registered. This article is protected by copyright. All rights reserved.

Disseminated Verruconis gallopava infection in a patient with systemic lupus erythematosus in Japan: A case report, literature review, and autopsy case

Disseminated Verruconis gallopava infection is often reported in patients with severe immunodeficiency, such as those who have received an organ transplant or have hematological malignancies. The present report describes the first case of disseminated V. gallopava in a patient with systemic lupus erythematosus who used FK506 (Tacrolimus). In this case, β-D glucan was useful for diagnosis.

Scolecobasidium granulomatous pneumonia and abscess - an emerging opportunistic fungal pathogen: a case report

Scolecobasidium sp. are commensal soil and water thermophilic dematiaceous fungi. They are commonly isolated as contaminants from respiratory secretions due to their abundant presence in water supplies, but they are also rare yet emerging culprits producing severe opportunistic infections in immunocompromised individuals. The most consistent presentations reported in literature are life-threatening pulmonary and cerebral granulomatous lesions.

Occurrence of Ochroconis and Verruconis species in clinical specimens from the United States

Ochroconis is a dematiaceous fungus able to infect immunocompetent people. Recently, the taxonomy of the genus has been reevaluated, and the most relevant species, Ochroconis gallopava, was transferred to the new genus Verruconis. Due to the important clinical implications of these fungi and based on the recent classification, it was of interest to know the spectra of Ochroconis and Verruconis species in clinical samples received in a reference laboratory in the United States. A set of 51 isolates was identified morphologically and molecularly based on sequence analyses of the nuclear ribosomal RNA (nrRNA), actin, and β-tubulin genes. Verruconis gallopava was the most common species (68.6%), followed by Ochroconis mirabilis (21.5%). One isolate of Ochroconis cordanae was found, being reported for the first time in a clinical setting. The most common anatomical site of isolation was the lower respiratory tract (58.8%), followed by superficial and deep tissues at similar frequencies (21.6 and 19.6%, respectively). Interestingly, three new species were found, which are Ochroconis olivacea and Ochroconis ramosa from clinical specimens and Ochroconis icarus of an environmental origin. The in vitro antifungal susceptibilities of eight antifungal drugs against the Ochroconis isolates revealed that terbinafine and micafungin were the most active drugs.

Draft Genome Sequence of Ochroconis constricta UM 578, Isolated from Human Skin Scraping

Ochroconis constricta is a soilborne dematiaceous fungus that has never been reported to be associated with human infection. Here we report the first draft genome sequence of strain UM 578, isolated from human skin scraping. The genomic information revealed will contribute to a better understanding of this species.

Antifungal susceptibility patterns of opportunistic fungi in the genera Verruconis and Ochroconis

Species of Verruconis and species of Ochroconis are dematiaceous fungi generally found in the environment but having the ability to infect humans, dogs, cats, poultry, and fish. This study presents the antifungal susceptibility patterns of these fungi at the species level. Forty strains originating from clinical and environmental sources were phylogenetically identified at the species level by using sequences of the ribosomal DNA internal transcribed spacer (rDNA ITS). In vitro antifungal susceptibility testing was performed against eight antifungals, using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method. The geometric mean MICs for amphotericin B (AMB), flucytosine (5FC), fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), and posaconazole (POS) and minimum effective concentrations (MECs) for caspofungin (CAS) and anidulafungin (AFG) across the Ochroconis and Verruconis species were as follows, in increasing order. For Verruconis species, the values (μg/ml) were as follows: AFG, 0.04; POS, 0.25; ITC, 0.37; AMB, 0.50; CAS, 0.65; VRC, 0.96; 5FC, 10.45; and FLC, 47.25. For Ochroconis species, the values (μg/ml) were as follows: AFG, 0.06; POS, 0.11; CAS, 0.67; VRC, 2.76; ITC, 3.94; AMB, 5.68; 5FC, 34.48; and FLC, 61.33. Antifungal susceptibility of Ochroconis and Verruconis was linked with phylogenetic distance and thermotolerance. Echinocandins and POS showed the greatest in vitro activity, providing possible treatment options for Ochroconis and Verruconis infections.

Phaeohyphomycoses, emerging opportunistic diseases in animals

Emerging fungal diseases due to black yeasts and relatives in domestic or wild animals and in invertebrates or cold- and warm-blooded vertebrates are continually being reported, either as novel pathogens or as familiar pathogens affecting new species of hosts. Different epidemiological situations can be distinguished, i.e., occurrence as single infections or as zoonoses, and infection may occur sporadically in otherwise healthy hosts. Such infections are found mostly in mammals but also in cold-blooded animals, are frequently subcutaneous or cerebral, and bear much similarity to human primary disorders. Infections of the nervous system are mostly fatal, and the source and route of infection are currently unknown. A third epidemiological situation corresponds to pseudoepidemics, i.e., infection of a large host population due to a common source. It is often observed and generally hypothesized that the susceptible animals are under stress, e.g., due to poor housing conditions of mammals or to a change of basins in the case of fishes. The descriptions in this article represent an overview of the more commonly reported and recurring black fungi and the corresponding diseases in different types of animals.

Melanized fungi in human disease

Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes, including chromoblastomycosis, mycetoma, and phaeohyphomycosis. [corrected]. Many are soil organisms and are generally distributed worldwide, though certain species appear to have restricted geographic ranges. Though they are uncommon causes of disease, melanized fungi have been increasingly recognized as important pathogens, with most reports occurring in the past 20 years. The spectrum of diseases with which they are associated has also broadened and includes allergic disease, superficial and deep local infections, pneumonia, brain abscess, and disseminated infection. For some infections in immunocompetent individuals, such as allergic fungal sinusitis and brain abscess, they are among the most common etiologic fungi. Melanin is a likely virulence factor for these fungi. Diagnosis relies on careful microscopic and pathological examination, as well as clinical assessment of the patient, as these fungi are often considered contaminants. Therapy varies depending upon the clinical syndrome. Local infection may be cured with excision alone, while systemic disease is often refractory to therapy. Triazoles such as voriconazole, posaconazole, and itraconazole have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and optimal treatment of these uncommon infections.

Indoor wet cells harbour melanized agents of cutaneous infection

The biota of black fungi in humid indoor environments was established using a protocol that consisted of non-selective and selective isolation procedures. In total, 113 samples were taken from bathrooms of residences in The Netherlands, Germany and Austria. Samples were processed either (i) directly by culturing on agar media, or (ii) by pre-incubating samples for enrichment in mineral solutions with perlite granules under constant toluene atmosphere for three months. Dilutions from the latter were then cultured and incubated as were those directly plated to agar media. Black colonies were selected and identified by sequencing the rDNA Internal Transcribed Spacer (ITS) region. Twenty-eight strains of black fungi were found in 26 positive samples without enrichment, and 42 strains were isolated from 38 positive samples after enrichment in toluene. The great majority of black fungal species were members of the order Chaetothyriales, which is the main order of melanized human opportunistic pathogens. Cladosporium species (Capnodiales) were the most frequent isolates when no enrichment was applied, as opposed to Exophiala species (Chaetothyriales) with enrichment. The enrichment method provides insight into a fungal biota commonly occurring in homes which has previously been overlooked. Several species have been previously known only from cutaneous infections and could suggest that bathrooms are a likely reservoir of these fungi.

Successful treatment of Ochroconis gallopavum infection in an immunocompetent host

Ochroconis gallopavum, a dematiaceous fungus, is a rare cause disease in immunocompromised patients and epidemic encephalitis in poultry. We report the first case of active O. gallopavum pulmonary infection in an immunocompetent host with rapid and complete response to oral antifungal therapy.

Pathogenicity of Ochroconis gallopava isolated from hot springs in Japan and a review of published reports

Four strains of Ochroconis gallopava from 3 out of 15 Japanese hot springs were isolated. Colonies of the hot spring isolates were uniformly floccose and dark olive green on the surface and dark brown on their reverse side on potato dextrose agar (PDA) plates, however, they became felty, flat, and brownish-black, and produced a reddish-brown pigment after several times of subculture at room temperature. Shapes and sizes of conidia of the four strains were individual, while the D1/D2 domain of the large subunit ribosomal RNA gene sequences showed 99.7% identity in the GenBank database. The DNA pattern of the hot spring isolates amplified by species specific loop mediated isothermal amplification method were as the same pattern as that of a clinical isolate. The minimum inhibitory concentrations of antifungal agents to O. gallopava isolated from the hot springs were ranged from 0.5 to 1 microg/ml in amphotericin B, 1 to 16 microg/ml in flucytosine, 0.125 to 0.25 microg/ml in itraconazole, 1 to 4 microg/ml in miconazole, 16 to 64 microg/ml in flconazole and 0.03 to 0.5 microg/ml in micafungin. The isolates had fatal outcome in experimentally infected mice intravenously with severe invasiveness to brains and kidneys. These findings suggested that O. gallopava habitats in hot springs could be one of sources for infection.

Fatal systemic phaeohyphomycosis caused by Ochroconis gallopavum in a dog (Canis familaris)

A 5-year-old Shetland Sheepdog was presented with a history of weakness, ataxia, anemia, thrombocytopenia, and occasional seizures. The dog had been treated for 6 months with prednisone for inflammatory bowel disease. A positive titer for Ehrlichia canis was detected 6 months before referral. The initial physical examination revealed a weak, laterally recumbent dog with pale mucous membranes. Neurologic examination revealed multiple neurologic deficits. A complete blood cell count (CBC) revealed normochromic, normocytic, nonregenerative anemia; lymphopenia; thrombocytopenia; and neutrophilic and monocytic leukocytosis. Urinalysis revealed proteinuria, with a specific gravity of 1.045. The dog was unresponsive to treatment and died. At necropsy, there was severe serofibrinous peritonitis and pleuritis, with randomly scattered dark brown necrotic foci present in multiple organs, including liver, spleen, kidney, and pancreatic lymph node. Histologically, there were extensive regions of parenchymal necrosis surrounded by neutrophils admixed with epithelioid macrophages, lymphocytes, and pigmented fungal organisms. Numerous brown, 2 to 6 microm in diameter, septate, branching hyphae, subsequently identified as Ochroconis gallopavum (formerly Dactylaria constricta var. gallopava), were observed.

Rapid identification of Ochroconis gallopava by a loop-mediated isothermal amplification (LAMP) method

Ochroconis gallopava is a species of dematiaceous fungi recognized as a causative agent of zoonotic and emerging fungal infections. It affects the central nervous system and respiratory tracts of humans, birds and cats. We designed O. gallopava species-specific primer sets to aid in its identification by a loop-mediated isothermal amplification (LAMP) method based on the D1/D2 domain of the LSU rDNA sequence. The LAMP method successfully detected the gene from both fungal DNA and experimentally infected brains and spleens of mice and will be helpful in the diagnosis of O. gallopava infection.

Disseminated phaeohyphomycosis due toOchroconis gallopavumin the setting of advanced HIV infection

Disseminated phaeohyphomycosis is a rare and typically fatal infection caused by members of the dematiaceous fungi, and occurs almost universally in the setting of immunocompromise. We herein report a case of systemic phaeohyphomycosis caused by Ochroconis gallopavum in a patient with advanced HIV disease. A possible risk factor for this infection in our patient was heavy marijuana use. This case highlights both the diagnostic and management challenges posed by these infections. To our knowledge, this is the first reported case of disseminated phaeohyphomycosis due to Ochroconis gallopavum in a patient with HIV.

Disseminated Ochroconis gallopavum infection in a chronic lymphocytic leukemia: a case report and review of the literature on hematological malignancies

Disseminated fungal infection is an important cause of morbidity and mortality among patients with hematological malignancies. Ochroconis gallopavum is a dematiaceous and thermotolerant fungus that causes opportunistic infections in immunocompromised hosts. About only 30 cases of this organism infection have been reported worldwide. We report a disseminated Ochroconis gallopavum infection in a B-cell chronic lymphocytic leukemia patient. In spite of intensive anti-fungal treatment, no improvement in the clinical condition was observed and the patient died 4 months after diagnosis of the infection. Ochroconis gallopavum infection is a potentially fatal disease in hematological malignancies.

Primary Central Nervous System Phaeohyphomycosis: A Review of 101 Cases

Phaeohyphomycosis refers to infections caused by darkly pigmented fungi. These fungi rarely cause life-threatening disease. We reviewed 101 cases of culture-proven primary central nervous system phaeohyphomycosis reported in the English-language literature from 1966 to 2002. The most frequently isolated species was Cladophialophora bantiana. The next most frequent isolate was Ramichloridium mackenziei, seen exclusively in patients from the Middle East. More than one-half of the cases occurred in patients with no known underlying immunodeficiency. Mortality rates were high regardless of immune status. Therapy is not standardized, although the combination of amphotericin B, flucytosine, and itraconazole may improve survival rates. Newer azoles, such as voriconazole, also have a broad spectrum of activity against these fungi, although clinical experience is limited. Complete excision of brain lesions may provide better results than simple aspiration. An aggressive medical and surgical approach is warranted in treating these infections to optimize outcomes.

Antifungal therapy--state of the art at the beginning of the 21st century

The most relevant information on the present state of the art of antifungal chemotherapy is reviewed in this chapter. For dermatomycoses a variety of topical antifungals are available, and safe and efficacious systemic treatment, especially with the fungicidal drug terbinafine, is possible. The duration of treatment can be drastically reduced. Substantial progress in the armamentarium of drugs for invasive fungal infections has been made, and a new class of antifungals, echinocandins, is now in clinical use. The following drugs in oral and/or intravenous formulations are available: the broad spectrum polyene amphotericin B with its new "clothes"; the sterol biosynthesis inhibitors fluconazole, itraconazole, and voriconazole; the glucan synthase inhibitor caspofungin; and the combination partner flucytosine. New therapy schedules have been studied; combination therapy has found a significant place in the treatment of severely compromised patients, and the field of prevention and empiric therapy is fast moving. Guidelines exist nowadays for the treatment of various fungal diseases and maintenance therapy. New approaches interfering with host defenses or pathogenicity of fungal cells are being investigated, and molecular biologists are looking for new targets studying the genomics of pathogenic fungi.

Uncommon opportunistic fungi: new nosocomial threats

During the past two decades opportunistic fungal infections have emerged as important causes of morbidity and mortality in patients with severe underlying illnesses and compromised host defenses. While Aspergillus and Candida spp. collectively account for the majority of these infections, recent epidemiological trends indicate a shift towards infections by Aspergillus spp., nonalbicans Candida spp., as well as previously uncommon opportunistic fungi. Apart from an expanding number of different Zygomycetes, previously uncommon hyaline filamentous fungi (such as Fusarium species, Acremonium species, Paecilomyces species, Pseudallescheria boydii, and Scedosporium prolificans), dematiaceous filamentous fungi (such as Bipolaris species, Cladophialophora bantiana, Dactylaria gallopava, Exophiala species, and Alternaria species) and yeast-like pathogens (such as Trichosporon species, Blastoschizomyces capitatus, Malassezia species, Rhodotorula rubra and others) are increasingly encountered as causing life threatening invasive infections that are often refractory to conventional therapies. On the basis of past and current trends, the spectrum of fungal pathogens will continue to evolve in the settings of an expanding population of immunocompromised hosts, selective antifungal pressures, and shifting conditions in hospitals and the environment. An expanded and refined drug arsenal, further elucidation of pathogenesis and resistance mechanisms, establishment of in vitro/in vivo correlations, incorporation of pharmacodynamics, combination- and immunotherapies offer hope for substantial progress in prevention and treatment.

Disseminated Dactylaria constricta infection in a renal transplant recipient

We report the case of a 32-year-old renal transplant recipient who developed disseminated Dactylaria constricta infection. The patient died despite treatment with amphotericin B, itraconazole, and fluconazole.

A case report of a dactylaria fungal infection in a lung transplant patient

Dematiaceous fungi such as Dactylaria gallopava are becoming more prevalent in transplant patients, with 50% of outcomes being fatal. In this report, we describe a 32-year-old woman who presented with swelling in the right shoulder area and right lateral neck. On further investigation with a CT scan, a fluid collection in the shoulder was identified, drained, and subsequently grew D gallopava. We report the successful treatment of an invasive Dactylaria infection in a lung transplant patient predominantly by medical chemotherapy, although surgical incision and drainage was performed on one of the fungal lesions.

Multiple lung abscesses due to Ochroconis gallopavum, a dematiaceous fungus, in a nonimmunocompromised wood pulp worker

An occurrence of multiple chronic lung abscesses managed by lobectomy is described. These abscesses were present for 13 years in the patient, a nonimmunocompromised wood pulp worker. The patient had hemoptysis at presentation. The organism isolated was Ochroconis gallopavum, a dematiaceous fungus known to cause disease in immunocompromised patients and epidemic encephalitis in poultry. The fungus is typically found in warm environments and in decaying compost; for this reason, we postulate that his illness was occupationally acquired.

Fluconazole in transplant recipients: options and limitations

Fluconazole is currently a first-line agent used for therapy of non-critically ill patients with candidal infection. Its efficacy, the availability of an oral formula, and its relatively low toxicity make it a very attractive drug for use in many clinical situations. The advisability of prophylaxis and empirical treatment in transplant patients is a difficult issue for the following reasons: the potential emergence of resistance to the azoles, the lack of solid data establishing its advantage over placebo and/or oral nonabsorbable antifungal agents in some of the clinical conditions encountered, its ineffectiveness against molds, and its cost. Judicious use of fluconazole where its efficacy has been well established would provide the best therapy for patients and would limit the emergence of potential pathogens. As new antifungal agents are approved for clinical use, appropriate clinical trials will need to be designed and conducted in order for clinicians to make rational decisions in selecting the most appropriate drug for the specific indication. Prophylaxis and treatment with fluconazole in various transplant situations is reviewed.

Emerging fungal pathogens: evolving challenges to immunocompromised patients for the twenty-first century

Opportunistic fungi have emerged during the past decade as important causes of morbidity and mortality in immunocompromised patients. Candida species constitute the third to fourth most common causes of nosocomial blood stream infections, and Aspergillus species have emerged as the most common infectious cause of pneumonic mortality in bone marrow/stem cell transplant recipients. Among HIV-infected patients, meningoencephalitis due to Cryptococcus neoformans ranks among the most common AIDS-defining infections. Hyaline septated filamentous fungi, such as Fusarium species, Acremonium species, Paecilomyces species, and Trichoderma species, are increasingly reported as causing invasive mycoses refractory to conventional therapy. Dematiaceous septated filamentous fungi, such as Pseudallescheria boydii, Bipolaris species, and Cladophialophora bantiana cause pneumonia, sinusitis, and CNS infection unresponsive to current therapy. An increasing number of different members of the class of Zygomycetes are reported as causing lethal infections, despite aggressive medical and surgical interventions. Yet the treatment for zygomycosis has not changed in approximately 40 years. The prevalence of the endemic mycoses, such as those due to Penicillium marneffei, Coccidioides immitis, and Histoplasma capsulatum, has been reported to expand rapidly in response to environmental exposures and increased numbers of vulnerable hosts in endemic regions of the world. Dermatophytoses are occurring with increasing prevalence and morbidity in elderly and immunocompromised patients. As we enter the next millennium, we may anticipate that emergent fungal infections will continue to develop in the settings of permissive environmental conditions, selective antifungal pressure, and an expanding population of immunocompromised hosts.

Cerebral phaeohyphomycosis: report of a case from Nigeria

A fatal case of cerebral phaeohyphomycosis in a 45-year-old Nigerian woman is described. The main clinical features were loss of vision, constant severe headache and the presence of a tumorous mass in the brain as detected on operation. Histology revealed granulomatous tissue reaction with fungal elements suggestive of Xylohypha bantiana.