Scedosporium apiospermum brain abscesses in an immunocompetent man with silicosis

Emerging Fungal Infections of the Central Nervous System in the Past Decade: A Literature Review

INTRODUCTION

Invasive fungal infections affecting the central nervous system (CNS) are a major health concern worldwide associated with high mortality rates. Their increased incidence is largely due to an increase in the vulnerable immunocompromised population, changing environmental factors, and development of more accurate diagnostic methods. The aim of this article is to identify fungal causes of CNS infections that are recently emerging or have the potential to become emerging pathogens in the near future, as well as their clinical characteristics, including: Candida auris, Trichosporon spp., Blastomyces spp., Sporothrix spp., Talaromyces marneffei, Lomentospora prolificans, and Scedosporium spp.

METHODS

A review of the literature in PubMed in the last ten years was conducted to identify central nervous system infections caused by each of these fungi.

RESULTS

The review identified 10 cases caused by C. auris, 5 cases by Trichosporon spp., 82 cases by Blastomyces spp., 36 cases by Sporothrix spp., 21 cases by T. marneffei, 22 cases by Lomentospora prolificans, and 42 cases by Scedosporium spp.

DISCUSSION

The exact burden of these diseases remains difficult to ascertain, but their apparent rise underscores the urgent need for improved diagnostic, treatment, and management strategies against CNS fungal pathogens to improve outcomes against these life-threatening infections.

Scedosporiosis and lomentosporiosis: modern perspectives on these difficult-to-treat rare mold infections

SUMMARYAlthough Scedosporium species and Lomentospora prolificans are uncommon causes of invasive fungal diseases (IFDs), these infections are associated with high mortality and are costly to treat with a limited armamentarium of antifungal drugs. In light of recent advances, including in the area of new antifungals, the present review provides a timely and updated overview of these IFDs, with a focus on the taxonomy, clinical epidemiology, pathogenesis and host immune response, disease manifestations, diagnosis, antifungal susceptibility, and treatment. An expansion of hosts at risk for these difficult-to-treat infections has emerged over the last two decades given the increased use of, and broader population treated with, immunomodulatory and targeted molecular agents as well as wider adoption of antifungal prophylaxis. Clinical presentations differ not only between genera but also across the different Scedosporium species. L. prolificans is intrinsically resistant to most currently available antifungal agents, and the prognosis of immunocompromised patients with lomentosporiosis is poor. Development of, and improved access to, diagnostic modalities for early detection of these rare mold infections is paramount for timely targeted antifungal therapy and surgery if indicated. New antifungal agents (e.g., olorofim, fosmanogepix) with novel mechanisms of action and less cross-resistance to existing classes, availability of formulations for oral administration, and fewer drug-drug interactions are now in late-stage clinical trials, and soon, could extend options to treat scedosporiosis/lomentosporiosis. Much work remains to increase our understanding of these infections, especially in the pediatric setting. Knowledge gaps for future research are highlighted in the review.

Myocarditis and brain abscess caused by disseminated Scedosporium boydii infection

Scedosporium spp. is a fungal species documented as the cause of infections involving the lungs, brain, and other organ systems in both immunocompetent and immunocompromised individuals. Many cases of this type of fungal infection occurring in immunocompetent patients are subsequent to traumatic injury or drowning events in or near waters containing the fungi. Infection commonly involves the lungs. Rarely, it has been shown to cause disease in the endocardium, but there is even less documentation of the fungi invading the myocardium and causing myocarditis. In this report, we present a case of disseminated Scedosporium boydii infection in a 52-year-old male patient without any known risk factors. He presented with acute onset chest pain and dyspnea accompanied by bilateral lower extremity edema. He was found to have new onset heart failure with reduced ejection fraction, and his hospital course was complicated by pneumonia, disseminated intravascular coagulation (DIC), and brain abscess formation. Multiple blood cultures failed to reveal the source of the infection. At autopsy, septated branching hyphae were identified invading both the myocardium and the cortical brain tissue. DNA sequencing revealed the fungal organisms to be Scedosporium boydii. This case reinforces the importance of autopsies in the clinical setting. It not only established the definitive diagnosis of an unexpected fungal infection, but it also helped to recognize new clinical and pathologic features of this particular fungal organism.

A systemic infection involved in lung, brain and spine caused by Scedosporium apiospermum species complex after near-drowning: a case report and literature review

Scedosporium apiospermum species complex are widely distributed fungi that can be found in a variety of polluted environments, including soil, sewage, and decaying vegetation. Those opportunistic pathogens with strong potential of invasion commonly affect immunosuppressed populations However, few cases of scedosporiosis are reported in immunocompetent individuals, who might be misdiagnosed, leading to a high mortality rate. Here, we reported an immunocompetent case of systemtic infection involved in lung, brain and spine, caused by S. apiospermum species complex (S. apiospermum and S. boydii). The patient was an elderly male with persistent fever and systemtic infection after near-drowning. In the two tertiary hospitals he visited, definite diagnosis was extremely difficult. After being admitted to our hospital, he was misdiagnosed as tuberculosis infection, before diagnosis of S. apiospermum species complex infection by the metagenomic next-generation sequencing. His symptoms were alleviated after voriconazole treatment. In the present case, the details associated with its course were reported and published studies on Scedosporium spp. infection were also reviewed, for a better understanding of this disease and reducing the misdiagnosis rate.

A Case of Invasive Fungal Infection Due to Scedosporium apiospermum in a Patient with Psoriasis

Scedosporium apiospermum (S. apiospermum) is typically reported to be involved in superficial and subcutaneous fungal infections but overlooked in invasive infections, which is associated with a high mortality rate. It poses a diagnostic challenge due to its confusable characteristics to other hyaline hyphomycetes. Here, we reported a psoriasis patient with an invasive S. apiospermum infection. The patient presents an abscess at the intermuscular space of the left hip and an increased C-reactive protein level. Pus culture showed white-greyish, cottonlike colonies with aerial mycelium and terminal oval conidia, suggesting S. apiospermum. This rare fungus was rapidly confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and RNA sequencing. The patient was successfully treated with voriconazole with no recurrence of the abscesses despite delayed treatment. This is the first such case infection report from China that described an unusual case of intermuscular space abscesses due to S. apiospermum. This report highlights the possibility of fungal infections in deeper tissue, as well as the necessity of thorough evaluation and microbiological diagnosis for invasive infections, particularly in immunocompromised patients.

An Eight Year Clinico-Microbiological Retrospective Study on Brain Abscesses in India

Background:

Intracranial abscesses have been a diagnostic and therapeutic challenge since time immemorial for both the microbiologists and the neurosurgeons. There is paucity of detailed studies documenting the infecting organism causing brain abscesses in South India.

Aims:

The study aimed at identifying and assessing the prevalence of aerobic, anaerobic bacteria and fungi associated with brain abscesses at a tertiary care hospital in South India.

Methods and Material:

Eight years data was collected from the records of culture reports from 2007 to 2010 and 2013 to 2018. The corresponding clinical case records were retrieved for the assessment of risk factors. Risk factors of brain abscess development were assessed based on clinical cases records.

Results:

Data from 140 brain abscess cases obtained over a period of 8 years were analyzed. Out of the 140 samples, 66 (47.14%) were culture positive in which 33 (50%) had single aerobic/facultative anaerobic bacteria, 20 (30.3%) had mixture of more than one aerobic/facultative anaerobic bacteria, 12 (18.18%) had single obligate anaerobic bacteria and 1(1.5%) sample had Mycobacterium tuberculosis isolated. Among the total 92 isolates, Pseudomonas aeruginosa (21/92, 23%) and Staphylococcus aureus (20/92, 22%) predominated. Bacteroides fragilis group was the most common obligate anaerobe isolated. There were no fungal isolates. As there were various isolates isolated, hence there is heterogeneity of isolates detected Neuroanatomically, parietal lobe (45/140, 32%) was the most common location. Otogenic infection was the major risk factor for parietal and temporal lobe abscess (P value < .05).

Conclusions:

It has become essential for the microbiologists to be aware of unusual isolates from brain abscess and its complex nature. Obscurity and difficulty in their microbiological diagnosis calls for more such detailed studies.

Endoscopic treatment of brain abscess

Background:

Treatment of brain abscess is still a subject of controversy. The main treatment is surgical, although medical therapy alone can be used for selected cases. The treatment of choice is aspiration, which may be performed with the aid of an endoscope or by freehand technique, with or without stereotactic or intraoperative ultrasound guidance. Excision is valuable in some cases. We are reporting our results of endoscopic approach in 12 patients.

Methods:

This study included 12 patients of brain abscesses treated between January 2015 and January 2018. All the cases except those with small abscesses (<3.0 cm in diameter) were included in the study. Rigid endoscope was used. Follow-up CT scan was done in all cases within 7 and 30 days after surgery. Follow-up periods ranged between 3 and 6 months.

Results:

There were 11 patients with a history of chronic otitis media and one patient who suffered from congenital cyanotic heart disease. Glasgow Coma Score (GCS) was 5 in one patient, 13 in two cases, and 14–15 in 9 cases. There were one cerebellar, six temporal, and five frontal abscesses. All the patients recovered completely except one who died (GCS 5). There was no procedure-related complication. Hospital stay ranged from 14 to 45 days with an average of 28 days. The endoscopy aided visualization of multiloculations and septation in eight patients which allowed the opening of the septations and complete evacuation.

Conclusion:

Endoscopic aspiration is safe, easy, and represents an effective way of treatment of brain abscess through proper visualization. It can be used for ensuring the complete aspiration of contents, control of any bleeding point, and also for multiloculated abscess to identify and open the septations which may not be possible in stereotactic or any other guided aspirations.

Severe Scedosporium apiospermum Infection in a Recent Renal Transplant Recipient: Case Report

Infections in transplanted patients are still an important cause of morbidity and mortality. Among them, fungal infections with pathogens have become increasingly more prevalent in the last decade. We report the clinical course and management of disseminated Scedosporium apiospermum infection in a kidney transplant recipient, with microbiological isolation of the fungus in cerebrospinal fluid culture. S apiospermum is a fungus that is distributed worldwide and can be grown from soil samples or stagnant water. Disseminated infection is the most frequent form of infection, with cerebral involvement in most cases, which leads to a very high mortality (around 75%). Post-transplant renal infections require a thorough evaluation. Specifically, a high suspicion index is necessary, considering Scedosporium infection among the differential diagnosis of invasive fungal diseases in renal transplantation patients. It is essential to confirm the microbiological diagnosis for an adequate diagnosis and treatment.

Outcome of burr-hole aspiration of brain abscess

Objective

To determine the clinical outcome of burr-hole aspiration of brain abscess.

Methods

We analyzed 100 cases of intracranial abscess, treated surgically from January 2015 and October 2016 at Jinnah Postgraduate Medical Centre (JPMC). All patients were treated with burr hole aspiration. Medical records were analyzed for demographics, clinical presentation, predisposing factors, abscess location on imaging and clinical outcomes were charted.

Results

The study included 100 patients with 73 (73%) males and 27 (27%) females with a mean age of 36.69±10.96 years. Mean duration of signs and symptoms was 8.50±4.2 days. The most common presenting complaint was altered sensorium in 70 (70%) patients and commonest source of infection was otitis media seen in 27 patients (27%). The GCS on presentation was 13 in 57 (57%) cases. The parietal region was the most common site in 43 patients (43%), followed by frontal region in 33 patients (33%). Complete resolution of abscess with recovery of preoperative neuro-deficit was seen in 77 (77%) patients and recovery with major neuro-deficit was observed in 10 (10%) cases while 13 (13%) patients expired.

Conclusion

Early diagnosis, optimum follow-up and timely burr-hole aspiration are the keys in the proper management of brain abscess.

Biofilm Formation by Pseudallescheria/Scedosporium Species: A Comparative Study

Pseudallescheria/Scedosporium species are medically important fungi that are present in soil and human impacted areas and capable of causing a wide spectrum of diseases in humans. Although little is known about their pathogenesis, their growth process and infection routes are very similar to those of Aspergillus species, which grow as biofilms in invasive infections. All nine strains tested here displayed the ability to grow as biofilms in vitro and to produce a dense network of interconnected hyphae on both polystyrene and the surfaces of central venous catheters, but with different characteristics. Scedosporium boydii and S. aurantiacum clinical isolates were able to form biofilms faster than the corresponding environmental strains, as evidenced in kinetic assays for S. boydii and CLSM for S. aurantiacum. Biofilms formed by Pseudallescheria/Scedosporium species had significantly higher resistance to the class of antifungal azole than was observed in planktonic cells, indicating a protective role for this structure. In addition, the clinical S. aurantiacum isolate that formed the most robust biofilms was also more virulent in a larvae Galleria mellonella infection model, suggesting that the ability to form biofilms enhances virulence in Pseudallescheria/Scedosporium species.

Scedosporiosis in a Combined Kidney and Liver Transplant Recipient: A Case Report of Possible Transmission from a Near-Drowning Donor

Scedosporium spp. are saprobic fungi that cause serious infections in immunocompromised hosts and in near-drowning victims. Solid organ transplant recipients are at increased risk of scedosporiosis as they require aggressive immunosuppression to prevent allograft rejection. We present a case of disseminated Scedosporium apiospermum infection occurring in the recipient of a combined kidney and liver transplantation whose organs were donated by a near-drowning victim and review the literature of scedosporiosis in solid organ transplantation.

A retrospective study on the aetiology, management, and outcome of brain abscess in an 11-year, single-centre study from China

BACKGROUND

Brain abscesses continue to pose diagnostic and therapeutic challenges in developed and developing countries. Their aetiology and management remain complex and unclear, making improvement of treatments and outcome difficult.

METHODS

To determine the demographics, management, and the variables that affect the outcome in subjects with brain abscesses treated at a single centre over an 11-year period, we retrospectively analysed data in 60 patients with brain abscesses surgically treated with stereotactically guided aspiration or open craniotomy excision in Shanghai Changzheng Hospital between January 2001 and December 2011. Such variables as age, gender, Glasgow Coma Scale (GCS) score at admission, clinical presentation, location, number of lesions, predisposing factors, mechanism of infection, aetiological agent, and therapy were analysed independently.

RESULTS

Our analysis demonstrated that patient age and gender were factors that influence the occurrence of brain abscess; female patients and patients greater than 40 years of age were most likely to suffer a brain abscess. We also found that a patient's GCS score upon admission did not influence outcome. While frequency of successful culturing of the infectious agent was low, positive cultures were obtained in only 8 of the cases (13.33%), in which the most common isolate was Streptococcus milleri. Outcome was favourable in 78.33% of the subjects, while the mortality rate was 20%. The outcome of one patient was poor due to the abscess in the basal ganglia region.

CONCLUSIONS

Stereotactically guided aspiration is an effective treatment for brain abscess with an overall favourable outcome. Mortality due to brain abscess was not directly related to surgery nor surgical technique. Additional studies will continue to reveal patients trends that may improve treatment for brain abscess.