Cladosporiosis (cerebral phaeohyphomycosis) of brain--a case report

From Skin and Gut to the Brain: The Infectious Journey of the Human Commensal Fungus Malassezia and Its Neurological Consequences

The human mycobiome encompasses diverse communities of fungal organisms residing within the body and has emerged as a critical player in shaping health and disease. While extensive research has focused on the skin and gut mycobiome, recent investigations have pointed toward the potential role of fungal organisms in neurological disorders. Among those fungal organisms, the presence of the commensal fungus Malassezia in the brain has created curiosity because of its commensal nature and primary association with the human skin and gut. This budding yeast is responsible for several diseases, such as Seborrheic dermatitis, Atopic dermatitis, Pityriasis versicolor, Malassezia folliculitis, dandruff, and others. However recent findings surprisingly show the presence of Malassezia DNA in the brain and have been linked to diseases like Alzheimer's disease, Parkinson's disease, Multiple sclerosis, and Amyotrophic lateral sclerosis. The exact role of Malassezia in these disorders is unknown, but its ability to infect human cells, travel through the bloodstream, cross the blood-brain barrier, and reside along with the lipid-rich neuronal cells are potential mechanisms responsible for pathogenesis. This also includes the induction of pro-inflammatory cytokines, disruption of the blood-brain barrier, gut-microbe interaction, and accumulation of metabolic changes in the brain environment. In this review, we discuss these key findings from studies linking Malassezia to neurological disorders, emphasizing the complex and multifaceted nature of these cases. Furthermore, we discuss potential mechanisms through which Malassezia might contribute to the development of neurological conditions. Future investigations will open up new avenues for our understanding of the fungal gut-brain axis and how it influences human behavior. Collaborative research efforts among microbiologists, neuroscientists, immunologists, and clinicians hold promise for unraveling the enigmatic connections between human commensal Malassezia and neurological disorders.

An updated comprehensive systematic review of Cladophialophora bantiana and analysis of epidemiology, clinical characteristics, and outcome of cerebral cases

Cladophialophora bantiana is a phaeoid fungus that only rarely has been isolated from sources other than the human brain. It has a particular tropism for the central nervous system (CNS). We have integrated and updated large-scale data related to several aspects of C. Bantiana and reviewed all the available reports on its cerebral infections, focusing on their geographical distribution, infection routes, immune status of infected individuals, type and location of infections, clinical manifestations and treatment and outcome, briefly looking over the spectrum of other disease entities associated with C. bantiana, that is, extra-cerebral and animal infections and on the environmental sources of this fungus. Among the agents of phaeohyphomycosis, a term used to describe an infection caused by a dark pigmented fungus, C. bantiana has some significant specific features. A total of 120 case reports were identified with a significantly higher percentage of healthy subjects than immune-debilitated patients (58.3% vs. 41.7%). Infections due to C. bantiana occur worldwide. The main clinical manifestations are brain abscess (97.5%), coinfection of brain tissue and meninges (14.2%) and meningitis alone (2.5%). Among immunocompetent patients, cerebral infection occurred in the absence of pulmonary lesions. The mortality rate is 65.0% regardless of the patient's immune status. The therapeutic options used include surgery or antifungals alone, and the combination of both, in most cases the fatal outcome being rapid after admission. Since the fungus is a true pathogen, laboratory workers should be made aware that BioSafety Level-3 precautions might be necessary.

Fungal brain abscess caused by "Black Mold" (Cladophialophora bantiana) - A case report of successful treatment with an emphasis on how fungal brain abscess may be different from bacterial brain abscess

Background:

Central nervous system infection with Cladophialophora bantiana (Black Mold) is rare. It carries a high mortality rate, that is more than 70%, despite multimodal therapy.

Case Description:

We present a rare case of “black mold” fungal brain abscess that was successfully treated with good patient outcome. The case is unusual because there were two fungal brain abscesses located bilaterally symmetrically in the mesial frontal lobes, and the response to different treatment strategies was well documented by over 25 magnetic resonance imaging (MRI) scans. Initial attempts to treat these lesions by repeated surgical excision and systemic amphotericin B was followed by continued growth rather than resolution. We realized that the application of treatment principles learned from bacterial brain abscess may not transpose intuitively to the treatment of fungal brain abscess. Therefore, a new treatment strategy was adopted that avoided further attempts at resection in favor of long-term oral voriconazole and repeated intracavitary aspiration and instillation of amphotericin B on an outpatient basis. Without further resection, the lesions stabilized and the aspirates eventually sterilized, however, the enhancing capsule never resolved on MRI scans. All treatment was stopped after 1 year. The apparently sterilized lesions have been followed for an additional 3 years without further growth, and the patient remains functionally, intellectually, and behaviorally normal.

Conclusion:

We conclude that, in the case of fungal abscess, it may be preferable to sterilize the lesion in situ rather than attempting to achieve resolution on imaging studies by repeated surgical resection of the capsule which can be counterproductive. This strategy accepts that the capsule may be important to the patient's immune defense against the fungus. Helping that defense barrier with intracapsular and systemic antifungal agents, rather than capsular removal, may be the better strategy for patients in whom early aggressive resection has failed. The basis for the apparent differences in the response of fungal versus bacterial brain abscess to surgical resection is discussed in the light of pathological findings from this and other cases.

Cerebral Phaeohyphomycosis due to Cladophialophora bantiana - A Case Report and Review of Literature from India

Cerebral phaeohyphomycosis is a rare disease caused by dematiaceous fungi. It has poor prognosis irrespective of the immune status of the patient. Cladophialophora bantiana is the most commonly isolated species. We report a case of multiple brain abscesses caused by C. bantiana in an immune competent patient. The diagnosis was based on CT scan of head, direct examination and culture of the aspirate from the abscess. Despite complete surgical resection of the abscesses and antifungal therapy with amphotericin B and voriconazole the patient could not be saved. All the cases of cerebral phaeohyphomycosis due to this rare neurotropic fungus reported from India between 1962 and 2009 have also been reviewed.

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.

Cerebral phaeohyphomycosis--a cure at what lengths?

Cerebral phaeohyphomycosis is a fungal infection of the brain typically caused by Cladophialophora bantiana, Exophiala dermatitidis, and Rhinocladiella mackenziei, all of which belong to the order Chaetothyriales. The disease results in black, necrotic brain tissue, black pus, and black cerebrospinal fluid. Pathogens usually reach the brain through the bloodstream or lymphatic fluid and occasionally through direct spreading or accidental inoculation. Patients can present with hemiparesis, tonic spasm, headache, fever, sensory variation, cerebral irritation, and even psychotic behavioural changes. Radiological images are characterised by ring-enhanced signs and hyperdense and hypodense lesions. Pathological features frequently include black-to-brown necrotic tissue or dark-coloured pus, granulomatous inflammation, giant cell vasculitis, and pigmented fungal elements, which are easily seen on a direct potassium hydroxide smear, a rapid method for diagnosis. Black fungi can be cultured from a biopsy specimen. Combined antifungal chemotherapy, surgical debridement, and careful immunological interventions are strongly recommended to eradicate these intractable infections.

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.

Phaeohyphomycosis of the central nervous system in immunocompetent hosts: report of a case and review of the literature

BACKGROUND

Phaeohyphomycosis refers to infections caused by phaeoid fungi that can have an aggressive course in normal hosts. Involvement of the central nervous system may occur with a generally poor outcome. Clinical report and literature review: We report a case of Bipolaris sp. brain abscess in an immunologically competent host. We also review all previous cases of cerebral phaeohyphomycosis in normal hosts reported in the literature to date.

CONCLUSIONS

Central nervous system phaeohyphomycosis remains an unusual disease; however, its incidence has been increasing in recent years. The prognosis of this condition is still poor, despite medical and surgical interventions. Aggressive diagnostic approaches and careful interpretation of cultures might modify the natural history of this disease.

Cerebral phaeohyphomycosis in an immunodeficient child treated medically with combination antifungal therapy

Cerebral phaeohyphomycosis is a rare fungal infection with a poor prognosis when using conventional antifungal therapy in the absence of neurosurgical intervention. We present a case of a pediatric patient with inoperable Cladophialophora bantiana cerebral abscesses. To our knowledge, this child's case is the first reported to be treated with the combination of the newer triazole voriconazole and the new echinocandin caspofungin. Although our patient subsequently died, the natural rapid progression of the disease seemed to be altered by the antifungal combination alone, in the absence of surgery. Despite the fatal outcome for our patient, we encourage other clinicians to try unique medical approaches for this historically life-threatening infection when adjunctive surgery is impossible.

Imaging in phaeohyphomycosis of the brain: case report

A case of multiple, conglomerated brain abscesses due to Xylohypha bantiana, with unique imaging features, is presented. This is the first culture-proven case of brain infection due to this fungus in the neuroimaging literature.

Cutaneous phaeohyphomycosis due to Cladosporium cladosporioides

A 54-year-old man, affected by pemphigus vulgaris and severe steroid-induced diabetes, developed seven red-brown, firm, slightly raised 0.1-1 cm papular lesions on the anterior aspect of both knees and thighs. A cutaneous biopsy showed a granulomatous infiltrate with numerous fungal elements scattered in the dermis and also within giant cells. Cultures of cutaneous biopsy fragments on Sabouraud glucose agar in presence of chloramphenicol resulted in the growth of dark-green colonies at 25 degrees C. They were identified as typical Cladosporium cladosporioides. As far as we know, this species was previously isolated only in an HIV-seropositive patient as opportunistic pathogen in the site of skin testing.

Cerebral phaeohyphomycosis caused by Xylohypha bantiana

Cerebral phaeohyphomycosis is a rare fungal infection of man. There are approximately 53 published cases to date. Xylohypha bantiana has been shown by histology or culture to be the aetiological agent in 28 of these cases. Two cases of cerebral abscess caused by Xylohypha bantiana are presented. One patient was alive eight months after surgery and antifungal drug therapy. His was the first recorded case of cerebral phaeohyphomycosis treated with itraconazole. His course was complicated by adhesive arachnoiditis. The second patient died post-operatively without appropriate treatment.