Treatment of subcutaneous phaeohyphomycosis and prospective follow-up of 17 kidney transplant recipients

Phaeoacremonium iranianum - a new corneal pathogen

BACKGROUND

Phaeoacremonium is typically found in the environment and can cause diseases in woody plants. It is rarely responsible for infections in humans.

CASE PRESENTATION

In this report, we present a case of corneal infection caused by Phaeoacremonium iranianum. Caused a fan-shaped grayish-white ulcer measuring approximately 4 mm×3 mm inferior nasal cornea. The ulcer appeared relatively dry, with noticeable swelling and cloudiness in the surrounding cornea. The visual acuity after infection was 0.25. We started an aggressive antifungal therapy. Our antifungal susceptibility testing revealed the Minimum Inhibitory Concentration of anifengin was 4 µg/ml, Micafengin and carpofungin exceeding 8 µg/ml, fluorocytosine was 32 µg/ml, posaconazole was 1 µg/ml, voriconazole was 0.5 µg/ml, itraconazole was 2 µg/ml, fluconazole was 64 µg/ml, and amphotericin was 0.05 µg/ml. The patient underwent keratectomy combined with antifungal therapy. A month later, the conjunctiva of the right eye was congested, and a 4*4 mm corneal opacity was visible inferior nasal cornea, with local obvious thinning and a little keratic precipitates on the inner skin, and the infection has been controlled.

CONCLUSIONS

We detail the progression and treatment of this infection to contribute to the clinical understanding and management of such cases.

Phaeohyphomycosis of the Eyelid: A Case Report

Phaeohyphomycosis is a fungal infection caused by dematiaceous fungi that presents as a superficial, cutaneous, subcutaneous, or systemic infection. Subcutaneous phaeohyphomycosis is the most common manifestation and presents as a subcutaneous nodule or cystic lesions and abscesses. It usually results from traumatic implantation of the saprophytic fungus from soil and vegetative matter; therefore, the commonest sites of infection are the extremities. Rarely, involvement of the eyelid is seen with extensive facial infection or as a part of multiple nodular lesions in the face, scalp, or other regions in cases of cutaneous/subcutaneous phaeohyphomycosis. Here, we report a case of subcutaneous phaeohyphomycosis presenting as a solitary nodular lesion of the eyelid with extension into the anterior orbit in a 35-year-old immunocompetent male. The patient was successfully treated with combined surgical and medical therapy.

Deep cutaneous mycoses in kidney transplant recipients: Diagnostic and therapeutic challenges

Deep cutaneous mycoses (DCMs) are rare infections that extend throughout the dermis and subcutis, often occurring after inoculation with pathogenic fungi. Trends toward a growing incidence have been observed that may be partially related to an increasing population of solid organ transplant patients. The aim of this study is to describe the diagnostics and the outcomes of DCM among kidney transplant recipients so as to optimize their management. We performed a retrospective review of cases of DCM occurring among kidney transplant recipients in our institution over 12 years. Twenty cases were included. Lesions were only located on the limbs and presented mainly as single (10/20, 50%) nodular lesions (15/20, 75%), with a mean size of 3 cm. Direct mycological examination was positive for 17 patients (17/20, 85%) and the cultures were consistently positive. Thirteen different fungal species were observed, including phaehyphomycetes (n = 8), hyalohyphomycetes (n = 3), dermatophytes (n = 1), and mucorale (n = 1). The (1-3) beta-D-glucan antigen (BDG) was also consistently detected in the serum (20/20, 100%). Systematic imaging did not reveal any distant infectious lesions, but locoregional extension was present in 11 patients (11/14, 79%). Nineteen patients received antifungal treatment (19/20, 95%) for a median duration of 3 months, with surgery for 10 (10/20, 50%). There is a great diversity of fungal species responsible for DCMs in kidney transplant recipients. The mycological documentation is necessary to adapt the antifungal treatment according to the sensitivity of the species. Serum BDG positivity is a potentially reliable and useful tool for diagnosis and follow-up.

Invasive Rhinosinusitis Caused by Alternaria infectoria in a Patient with Autosomal Recessive CARD9 Deficiency and a Review of the Literature

Phaeohyphomycoses comprise a heterogeneous group of fungal infections caused by dematiaceous fungi and have primarily been reported in patients with underlying acquired immunodeficiencies, such as hematological malignancies or solid-organ transplants. Over the past decade, a growing number of patients with phaeohyphomycosis but otherwise healthy were reported with autosomal recessive (AR) CARD9 deficiency. We report a 28-year-old woman who presented with invasive rhinosinusitis caused by Alternaria infectoria. Following a candidate gene sequencing approach, we identified a biallelic loss-of-function mutation of CARD9, thereby further broadening the spectrum of invasive fungal diseases found in patients with inherited CARD9 deficiency. In addition, we reviewed 17 other cases of phaeohyphomycosis associated with AR CARD9 deficiency. Physicians should maintain a high degree of suspicion for inborn errors of immunity, namely CARD9 deficiency, when caring for previously healthy patients with phaeohyphomycosis, regardless of age at first presentation.

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.

Therapeutic management of subcutaneous phaeohyphomycosis and chromoblastomycosis in kidney transplant recipients: a retrospective study of 82 cases in a single center

BACKGROUND

Melanized fungi are a distinct group of pathogens that cause infections like chromoblastomycosis and phaeohyphomycosis, especially in a state of immunosuppression including solid organ transplant recipients. Guidelines for the treatment of these infections are lacking, and there is no available standard recommendation.

OBJECTIVE

To evaluate the therapeutic aspects of subcutaneous melanized fungal infections in kidney transplant recipients.

METHODS

A retrospective medical record was performed for kidney transplant recipients with melanized fungal infection evaluated in a single institution from January 1996 to December 2018.

RESULTS

Eighty-two episodes were noticed in our series. The treatment of subcutaneous phaeohyphomycosis was managed by surgical excision without antifungal therapy in 34 cases (34/68; 50%), and the association of both methods occurred in 18 cases (18/68; 26.5%). A complete surgical excision without antifungal therapy was observed in six (6/14; 42.9%) episodes of chromoblastomycosis, and combined treatment was possible in three (3/14; 21.4%) cases. Five episodes of chromoblastomycosis and 16 episodes of phaeohyphomycosis were managed only with antifungal therapy.

CONCLUSION

Management depends on the dermatologic lesion, immunosuppression condition, and anatomical cleavage plane. The sample size is still small in order to dictate a guideline, but it can be hard to execute a larger study given the rarity of this group of infections.

Phaeoacremonium species detected in fine needle aspiration: a rare case report

Background

Fine needle aspiration cytology (FNAC) with rapid on-site evaluation has a great potential for the diagnosis of fungal lesions and other opportunistic infections. Fungal infections have been in increasing trend in the past two decades due to immunosuppression, travel, and environmental exposure. Human disease caused by Phaeoacremonium species is rare and was first reported in 1974 as subcutaneous tissue infection in a renal transplant recipient.

Case presentation

We report a case of subcutaneous tissue swelling in a 67-year-old male, wherein FNAC was done with incidental detection of the fungus (Phaeoacremonium spp).

Conclusion

There are very few reported cases of subcutaneous infection in humans by Phaeoacremonium spp. Clinical suspicion and FNAC can play an important role in early detection of the fungus, prevent spread, and facilitating early treatment.

Study of tissue inflammatory response in different mice strains infected by dematiaceous fungi Fonsecaea pedrosoi

BACKGROUND

Diseases caused by melanized fungi include mycetoma, chromoblastomycosis and phaeohyphomycosis. This broad clinical spectrum depends on the dynamic interactions between etiologic agent and host. The immune status of the host influences on the development of the disease, as, an exemple. phaeohyphomicosis is more frequently observed in immunocompromised patients.

OBJECTIVES

Examine the histological inflammatory response induced by Fonsecaea pedrosoi in several different strains of mice (BALB/c, C57BL/6, Nude and SCID, and reconstituted Nude).

METHODS

Fonsecaea pedrosoi was cultivated on agar gel and a fragment of this gel was implanted subcutaneously in the abdominal region of female adult mice. After infection has been obtained, tissue fragment was studied histopathologically.

RESULTS

There were significant changes across the strains, with the nodular lesion more persistent in Nude and SCID mice, whereas in immunocompetent mice the lesion progressed to ulceration and healing. The histopathological analysis showed a significant acute inflammatory reaction which consisted mainly of neutrophils in the initial phase that was subsequently followed by a tuberculoid type granuloma in immunocompetent mice.

STUDY LIMITATIONS

There is no a suitable animal model for chromoblastomycosis.

CONCLUSIONS

The neutrophilic infiltration had an important role in the containment of infection to prevent fungal spreading, including in immunodeficient mice. The fungal elimination was dependent on T lymphocytes. The re-exposure of C57BL/6 mice to Fonsecaea pedrosoi caused a delay in resolving the infection, and appearance of muriform cells, which may indicate that re-exposure to fungi, might lead to chronicity of infection.

Emerging infectious diseases with cutaneous manifestations: Fungal, helminthic, protozoan and ectoparasitic infections

Given increased international travel, immigration, changing climate conditions, and the increased incidence of iatrogenic immunosuppression, fungal, protozoan, helminthic, and ectoparasitic infections that were once uncommon are being seeing more frequently in the Western hemisphere. However, the diagnosis and management of these infections is fraught with a lack of consistency because there is a dearth of dermatology literature on the cutaneous manifestations of these infections. In addition, delays in the diagnosis and treatment of these diseases can lead to significant patient morbidity and mortality. We review the epidemiology, cutaneous manifestations, diagnostic modalities, and treatment options for emerging fungal, protozoan, helminthic, and ectoparasitic infections. It should be noted, however, that throughout this review we cite statistics documenting their increased incidence to back-up these infections as emerging, and although some of the diagnoses are clinical, others rely on newer laboratory tests, and the possibility exists that the increased incidence could be caused by better detection methods.

Species diversity, antifungal susceptibility and phenotypic and genotypic characterisation of Exophiala spp. infecting patients in different medical centres in Brazil

The Exophiala genus is responsible for many superficial and invasive infections resulting from black fungi. Identification of Exophiala at the species level is based on morphological observations complemented by molecular tests. The aim of this study was to identify 23 clinical isolates of Exophiala spp. and evaluate the antifungal susceptibility to seven different agents. Molecular identification was based on an analysis of ITS region of rDNA using genomic databases. The micromorphology was evaluated by microculture and scanning electron microscopy. The susceptibility tests were performed using the antifungal agents 5-fluorocytosine (5-FC), amphotericin B (AMB), itraconazole (ITC), voriconazole (VRC), posaconazole (PSC), caspofungin (CFG) and terbinafine (TRB). The ITS analysis identified 100% of the following isolates as: E. dermatitidis (8), E. xenobiotica (6), E. bergeri (4), E. oligosperma (3), E. spinifera (1) and E. mesophila (1). The antifungal susceptibility tests showed that the triazoles compounds were in vitro the most active agents against Exophiala. ITS sequencing enabled the accurate identification of the 23 tested isolates. The triazoles, particularly itraconazole and posaconazole, exhibited MIC values lower than AMB, CAS and 5-FC. Although the guidelines do not indicate AMB for treatment against Exophiala spp., this study showed activity for all of the tested species, except E. mesophila.

Melanized fungal infections in kidney transplant recipients: contributions to optimize clinical management

OBJECTIVES

This is a retrospective and observational study addressing clinical and therapeutic aspects of melanized fungal infections in kidney transplant recipients.

METHODS

We retrospectively reviewed medical records of all patients admitted between January 1996 and December 2013 in a single institution who developed infections by melanized fungi.

RESULTS

We reported on 56 patients aged between 30 and 74 years with phaeohyphomycosis or chromoblastomycosis (0.54 cases per 100 kidney transplants). The median time to diagnosis post-transplant was 31.2 months. Thirty-four (60.8%) infections were reported in deceased donor recipients. Fifty-one cases of phaeohyphomycosis were restricted to subcutaneous tissues, followed by two cases with pneumonia and one with brain involvement. Most dermatological lesions were represented by cysts (23/51; 45.1%) or nodules (9/51; 17.9%). Exophiala spp. (34.2%) followed by Alternaria spp. (7.9%) were the most frequent pathogens. Graft loss and death occurred in two patients and one patient, respectively. Regarding episodes of subcutaneous phaeohyphomycosis, a complete surgical excision without antifungal therapy was possible in 21 of 51 (41.2%) patients. Long periods of itraconazole were required to treat the other 30 (58.8%) episodes of subcutaneous disease. All four cases of chromoblastomycosis were treated only with antifungal therapy.

CONCLUSIONS

Melanized fungal infections should be considered in the differential diagnosis of all chronic skin lesions in transplant recipients. It is suggested that the impact of these infections on graft function and mortality is low. The reduction in immunosuppression should be limited to severely ill patients.

Spectral Manifestation of Melanized Fungal Infections in Kidney Transplant Recipients: Report of Six Cases

Chromoblastomycosis and phaeohyphomycosis are melanized fungal infections, which affect skin and subcutaneous tissues in immunocompetent and immunosuppressed patients, as solid-organ transplant recipients, respectively. In this present study, we report six cases of melanized fungal infection in kidney transplant recipients. In five cases, culture of tissue specimens identified two cases of Exophiala spp. and three cases of Fonsecaea spp. Molecular identification was performed in three cases based on sequencing of rDNA (ITS region) that revealed the following agents: Exophiala xenobiotica, Exophiala bergeri and Fonsecaea monophora. Clinically, they presented verrucous lesion, erythematous-squamous plaque, nodules and lymphangitic distribution. Histopathological aspect was tuberculous granuloma, with concomitant presence of muriform bodies and hyphae. Some patients presented fungal transepithelial elimination. One patient received only terbinafine. Three patients underwent surgery, and two of them received itraconazole. In these four cases, the infection did not relapse. The other two patients were treated only with itraconazole, one of them is still under treatment and the other one was lost to follow-up. These patients presented clinical and histopathological characteristics ranging from resistant to nonresistant forms.

Subcutaneous Phaeohyphomycosis Caused By Pyrenochaeta Romeroi in a Kidney Transplant Recipient: A Case Report

Infections are Achilles heel of kidney transplant recipients. Opportunistic fungal infections are increasingly recognized in these patients. We report a case of kidney transplant recipient with skin and soft tissue infection caused by Pyrenochaeta romeroi, a dematiaceous fungi. Infection by this organism is rare.

Phaeohyphomycosis in Transplant Patients

Phaeohyphomycosis is caused by a large, heterogenous group of darkly pigmented fungi. The presence of melanin in their cell walls is characteristic, and is likely an important virulence factor. These infections are being increasingly seen in a variety of clinical syndromes in both immunocompromised and normal individuals. Transplant patients are especially at risk due their prolonged immunosuppression. There are no specific diagnostic tests for these fungi, though the Fontana-Masson stain is relatively specific in tissue. They are generally seen in a worldwide distribution, though a few species are only found in specific geographic regions. Management of these infections is not standardized due to lack of clinical trials, though recommendations are available based on clinical experience from case reports and series and animal models. Superficial infections may be treated without systemic therapy. Central nervous system infections are unique in that they often affect otherwise normal individuals, and are difficult to treat. Disseminated infections carry a high mortality despite aggressive therapy, usually with multiple antifungal drugs. Considerable work is needed to determine optimal diagnostic and treatment strategies for these infections.

Dual Invasive Infection with Phaeoacremonium parasiticum and Paraconiothyrium cyclothyrioides in a Renal Transplant Recipient: Case Report and Comprehensive Review of the Literature of Phaeoacremonium Phaeohyphomycosis

Despite increasing reports of human infection, data about the optimal care of Phaeoacremonium infections are missing. We report a case of an infection due to Phaeoacremonium parasiticum and Paraconiothyrium cyclothyrioides, initially localized to skin and soft tissue, in a kidney transplant patient. Despite surgical drainage and excision of the lesion and combination antifungal therapy with voriconazole and liposomal amphotericin B, a disseminated infection involving the lungs and brain developed and led to death. We performed a systematic literature review to assess the general features and outcome of human infections due to Phaeoacremonium species. Thirty-six articles were selected, and 42 patients, including ours, were reviewed. Thirty-one patients (74%) were immunocompromised because of organ or bone marrow transplantation (n = 17), diabetes or glucose intolerance (n = 10), rheumatoid arthritis or Still's disease (n = 4), chronic hematological diseases (n = 3), or chronic granulomatous disease (n = 3). Ten patients (24%) reported initial cutaneous trauma. Skin and soft tissue infections represented 57% of infections (n = 24), and disseminated infections, all occurring in immunocompromised patients, represented 14% of infections (n = 6). The main antifungal drugs used were azoles (n = 41) and amphotericin B (n = 16). Surgical excision or drainage was performed in 64% of cases (n = 27). The cure rate was 67% (n = 28). There were 10% cases of treatment failure or partial response (n = 4), 19% relapses (n = 8), and 7% losses to follow-up (n = 3). The death rate was 19% (n = 8). Management of Phaeoacremonium infections is complex because of slow laboratory identification and limited clinical data, and treatment relies on a combination of surgery and systemic antifungal therapy.

A rare case of subcutaneous phaeohyphomycosis caused by a Rhytidhysteron species: a clinico-therapeutic experience

BACKGROUND

Subcutaneous phaeohyphomycosis usually results from traumatic inoculation with the fungus and generally occurs in immunosuppressed men. Cladosporium, Exophiala, and Alternaria spp. are commonly implicated pathogens.

OBJECTIVES

We present a case of subcutaneous phaeohyphomycosis caused by Rhytidhysteron sp. that was refractory to conventional antifungal therapy.

CASE REPORT

A 72-year-old man with hypertension and diabetes presented with a multiloculated, large cystic swelling over the right dorsal foot. Laboratory findings and x-rays of the chest and left foot were normal.

RESULTS

Adequate control of the patient's diabetes was achieved, and the swelling was excised under itraconazole/terbinafine coverage. Histology showed multiple areas of neutrophilic abscess, epithelioid cells, foreign body giant cells, and multiple septate hyphae and yeast-like cells. Dematiaceous fungus was cultured but failed to produce spores. Sequencing of the isolate showed a match of > 99% with Rhytidhysteron rufulum. The patient demonstrated no response after one year of therapy with itraconazole/terbinafine. Weekly infiltration of the lesion with liposomal amphotericin B resulted in its complete resolution within 15 weeks.

CONCLUSIONS

Lesions of phaeohyphomycosis appear morphologically similar regardless of the organism implicated. Hence, their diagnosis rests entirely on the clinicopathological and microbiological presentation. Molecular studies may be required to identify a fungus if attempts to grow it in artificial culture media fail. Rhytidhysteron spp. are not known as pathogens in humans, and no treatment protocol exists. Intralesional amphotericin was highly effective in our patient and caused no systemic adverse effects. Voriconazole and posaconazole are effective against disseminated/visceral phaeohyphomycotic infections, but their efficacy against Rhytidhysteron spp. remains unstudied.

Subcutaneous phaeohyphomycosis due to Phialemoniopsis ocularis successfully treated by voriconazole

We report a case of subcutaneous infection in a 67 year-old Cambodian man who presented with a 5-month history of swelling of the right foot. Histopathology was compatible with phaeohyphomycosis and the hyphomycete Phialemoniopsis ocularis was identified by the means of morphological and molecular techniques. The patient responded well to a 6-month oral treatment with voriconazole alone.

Curvularia lunata: a rare cause of black-grain eumycetoma

Curvularia lunata is a dematiaceous fungus that rarely causes cutaneous infections in immunocompetent humans. We describe a case of mycetoma pedis caused by Curvularia lunata in a 50-year-old woman from a rural farming community who had prolonged morbidity due to diagnostic delay. She improved with antifungal therapy, showing a satisfactory clinical response after 12 months of treatment.

A case of Exophiala oligosperma successfully treated with voriconazole

Exophiala oligosperma is an uncommon pathogen associated with human infections, predominantly in immunocompromised hosts. Case reports of clinical infections related to E. oligosperma have been limited to 6 prior publications, all of which have shown limited susceptibility to conventional antifungal therapies, including amphotericin B, itraconazole, and fluconazole. We describe the first case of an E. oligosperma induced soft-tissue infection successfully treated with a 3-month course of voriconazole without persisting lesions.

Subcutaneous phaeohyphomycosis of the face presenting as rhinoentomophthoramycosis

OBJECTIVES

Subcutaneous phaeohyphomycosis is the most common variety of phaeohyphomycosis and presents as asymptomatic or mildly painful, localized cysts, abscesses, or sometimes chromoblastomycosis-like lesions over the feet, legs, or hands in about 60-85% of cases. It usually afflicts adults with some degree of immunosuppression.

METHODS

We report a 30-year-old man, who presented with features of recurrent sinusitis (episodes of fever, nasal stuffiness, paranasal sinus pain, and tenderness), mucosal hypertrophy of the maxillary sinuses, and mid-face swelling that was freely mobile and suggestive of rhinoentomophthoramycosis. He had no other associated illness.

RESULTS

Histology suggested tumid lupus erythematosus. The diagnosis was based on Fonsecaea pedrosoi cultured from a biopsy specimen.

CONCLUSIONS

Combination therapy with itraconazole and saturated solution of potassium iodide (SSKI) was more effective than itraconazole used alone.

Molecular identification of melanised non-sporulating moulds: a useful tool for studying the epidemiology of phaeohyphomycosis

Subcutaneous infections caused by melanised fungi have been increasingly reported among transplant patients, and these infections have the potential for blood and visceral dissemination. Some moulds, such as Mycelia sterilia, cannot grow and sporulate on different media, making their identification impossible by conventional methods. The fast and accurate identification of melanised fungi at the species level is important because species may have tropism to different organs and different susceptibilities to antifungal agents. Molecular tools have been reported to be helpful for the species identification of non-sporulating moulds. Our goal was to identify the species of M. sterilia isolates obtained from clinical samples of transplant patients using sequences of ITS and the D1/D2 regions of rDNA. Clinical samples were obtained from eight kidney transplant recipients who developed subcutaneous fungal infections. The diagnosis was confirmed by histopathology and conventional culture. Histopathology showed septated, melanised hyphae, and the cultures identified non-sporulating fungi. Therefore, the DNA from the M. sterilia isolates was subjected to PCR amplification and sequencing of the ITS and D1/D2 regions. Genus/species identification was obtained by comparison with gene banks. We obtained the following identifications: Alternaria sp. (2), Cochliobolus lunatus/Curvularia lunata (2), Cochliobolus hawaiiensis/Bipolaris hawaiiensis (1), Ochroconis sp. (1), Medicocopsis romeroi/Pyrenochaeta romeroi (1) and Nigrograna mackinnonii/Pyrenochaeta mackinnonii (1).

Phaeohyphomycosis Caused by Phaeoacremonium rubrigenum in an Immunosuppressive Patient: A Case Report and Review of the Literature

Phaeohyphomycosis (PHM) is a rare, deep fungal infection of the skin and subcutaneous tissues caused by dematiaceous fungi. In this report, we describe a case of PHM caused by Phaeoacremonium rubrigenum, which is generally known to infect woody plants. We detected the gray-blackish villi by biopsy culture material, and slide culture revealed the conidia arising from slightly tapering phialides. Furthermore, we differentiated these fungi as P. rubrigenum by Basic Local Alignment Search Tool (BLAST) algorithm. We performed surgical debridement of disseminated nodules and administered oral itraconazole for a duration of 4 weeks. One year after stopping itraconazole, there was no sign of relapsing subcutaneous nodules. To our knowledge, this is the third case report of PHM developing from skin infection by P. rubrigenum in human.

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.