Fatal Pseudallescheria boydii panencephalitis in a child after near-drowning

Invasive Scedosporium spp. and Lomentospora prolificans infections in pediatric patients: Analysis of 55 cases from FungiScope® and the literature

OBJECTIVES

Current knowledge on infections caused by Scedosporium spp. and Lomentospora prolificans in children is scarce. We therefore aim to provide an overview of risk groups, clinical manifestation and treatment strategies of these infections.

METHODS

Pediatric patients (age ≤18 years) with proven/probable Scedosporium spp. or L. prolificans infection were identified in PubMed and the FungiScope® registry. Data on diagnosis, treatment and outcome were collected.

RESULTS

Fifty-five children (median age 9 years [IQR: 5-14]) with invasive Scedosporium spp. (n = 33) or L. prolificans (n = 22) infection were identified between 1990 and 2019. Malignancy, trauma and near drowning were the most common risk factors. Infections were frequently disseminated. Most patients received systemic antifungal therapy, mainly voriconazole and amphotericin B, plus surgical treatment. Overall, day 42 mortality was 31%, higher for L. prolificans (50%) compared to Scedosporium spp. (18%). L. prolificans infection was associated with a shorter median survival time compared to Scedosporium spp. (6 days [IQR: 3-28] versus 61 days [IQR: 16-148]). Treatment for malignancy and severe disseminated infection were associated with particularly poor outcome (HR 8.33 [95% CI 1.35-51.40] and HR 6.12 [95% CI 1.52-24.66], respectively). Voriconazole use at any time and surgery for antifungal treatment were associated with improved clinical outcome (HR 0.33 [95% CI 0.11-0.99] and HR 0.09 [95% CI 0.02-0.40], respectively).

CONCLUSIONS

Scedosporium spp. and L. prolificans infections in children are associated with high mortality despite comprehensive antifungal therapy. Voriconazole usage and surgical intervention are associated with successful outcome.

An elusive diagnosis: Scedosporium apiospermum infection after near-drowning

A 51-year-old male was admitted in our institute following an episode of near-drowning. He later developed ventriculitis and cerebral ring-enhancing lesions. He died following a subarachnoid hemorrhage due to rupture of a mycotic aneurysm involving the right fetal posterior cerebral artery. Scedosporium apiospermum was isolated from the cerebrospinal fluid. Central nervous system invasion by S apiospermum may present insidiously in near-drowning patients and, therefore, requires a high index of suspicion. In cases with the characteristic cerebral ring-enhancing lesions and concomitant ventriculitis, treatment should be instituted while awaiting fungal culture. With this article we intend to alert neurologists, intensivists, and physicians to this near fatal infection, as early identification and prompt treatment with voriconazole may be life saving.

Invasive mycoses following trauma

Invasive fungal infection may afflict people with trauma in two ways: either by entry into tissue via penetrating trauma or by haematogenous spread in critically ill people with polytrauma. Penetrating injury allows the advance of ubiquitously present fungi into the human body. Miniscule foreign material fosters the establishment and growth of fungi within the traumatically changed tissue. The seriousness of the infection depends upon the type of injury, the body area and the person's general condition. Usually, the infection is confined to the cutis and subcutis; the fascia, muscles and bones are rarely affected. In the presence of immunocompromise, however, the fungus may spread rapidly and cause systemic disease. The following overview will focus on fungal infection associated with open wounds and fractures, particularly eye injury and with near-drowning, tropical mycetoma and nosocomial conditions. Post-traumatic invasive fungal infections are rare, but the surgeon should be alert to this possibility in cases with chronic inflammation and deferred healing of injuries, with or without systemic inflammatory response.

Infections caused by Scedosporium spp

Scedosporium spp. are increasingly recognized as causes of resistant life-threatening infections in immunocompromised patients. Scedosporium spp. also cause a wide spectrum of conditions, including mycetoma, saprobic involvement and colonization of the airways, sinopulmonary infections, extrapulmonary localized infections, and disseminated infections. Invasive scedosporium infections are also associated with central nervous infection following near-drowning accidents. The most common sites of infection are the lungs, sinuses, bones, joints, eyes, and brain. Scedosporium apiospermum and Scedosporium prolificans are the two principal medically important species of this genus. Pseudallescheria boydii, the teleomorph of S. apiospermum, is recognized by the presence of cleistothecia. Recent advances in molecular taxonomy have advanced the understanding of the genus Scedosporium and have demonstrated a wider range of species than heretofore recognized. Studies of the pathogenesis of and immune response to Scedosporium spp. underscore the importance of innate host defenses in protection against these organisms. Microbiological diagnosis of Scedosporium spp. currently depends upon culture and morphological characterization. Molecular tools for clinical microbiological detection of Scedosporium spp. are currently investigational. Infections caused by S. apiospermum and P. boydii in patients and animals may respond to antifungal triazoles. By comparison, infections caused by S. prolificans seldom respond to medical therapy alone. Surgery and reversal of immunosuppression may be the only effective therapeutic options for infections caused by S. prolificans.

Scedosporium apiospermum infection after near-drowning

Scedosporium apiospermum and its teleomorph (sexual form) Pseudallescheria boydii are ubiquitous saprophytic fungi, which under specific conditions, such as near-drowning, may cause therapy-refractory and life-threatening infections. We reviewed 22 cases (eight children and 14 adults) of S. apiospermum infection after near-drowning reported in the literature including an additional paediatric case from our institution. Scedosporiosis after near-drowning was associated with high mortality (16/23, 70%) even in immunocompetent hosts. It affected mainly young (mean age 24 years) and immunocompetent (83% with no apparent immune defect) males (male to female ratio 2.5 : 1). Scedosporiosis after near-drowning was a slow progressive disease (mean survival time 87 days) involving virtually all body organs. However, central nervous system (CNS) dissemination predominated (21/23, 91%) presenting mainly as multiple brain abscesses (15/23, 65%). All 23 patients showed preceding clinical and/or radiological evidence of lung disease indicating the mode of invasion. Diagnosis was delayed (median time to diagnosis 28 days) and was made by culture (16/23, 69.5%) or culture and tissue examination (7/23, 30.5%). The majority of the patients (20/23, 87%) received antifungal treatment and underwent neurosurgery. While the optimal treatment remains undefined, the most recent reports indicated voriconazole as a potentially effective option. Better knowledge of scedosporiosis after near-drowning could lead to improved intervention and ultimately to more favourable outcome.

Central nervous system pseudallescheriasis after near-drowning

BACKGROUND

Clinical characteristics of central nervous system (CNS) pseudallescheriasis after near-drowning have not been systematically analyzed.

METHODS

Review of cases reported in the English-language literature.

RESULTS

Sixteen patients were identified. The average period between the near-drowning episode and onset of clinical manifestations was 37 days. Common manifestations included fever, altered mental status, headache, seizures, and hemiparesis. All patients developed brain abscesses; however, imaging studies were normal at presentation in 6 patients. Cerebrospinal fluid neutrophilic pleocytosis, elevated protein, and decreased glucose were commonly observed. Most patients were treated with surgical resection and systemic amphotericin B or miconazole. Voriconazole was used in 2 patients. Twelve patients (75%) died. The average time between the near-drowning episode and death was 12 weeks. Four survivors received prompt treatment.

CONCLUSIONS

CNS pseudallescheriasis after near-drowning is highly lethal. Early diagnosis and aggressive medical and surgical interventions may improve survival.

Scedosporium apiospermum: changing clinical spectrum of a therapy-refractory opportunist*

Current knowledge on the opportunist Scedosporium apiospermum (teleomorph: Pseudallescheria boydii), generated over a period of more than 120 years, is reviewed. The natural environmental habitat of the fungus is unknown; nutrient-rich, brackish waters like river estuaria have been suggested. The fungus is strongly promoted by agricultural and particularly by industrial pollution.

Lethal brain abscess due to the fungusScedosporium apiospermum(teleomorphPseudallescheria boydii) after a near-drowning incident: case report and review of the literature

A 39-year-old healthy man developed a brain abscess weeks after a near-drowning incident. Scedosporium apiospermum, the anamorph of Pseudallescheria boydii, was isolated from the abscess. The patient died 153 days after the accident despite antifungal therapy. We discuss the role of antifungals and review the literature for comparable cases.

Infection of the CNS by Scedosporium apiospermum after near drowning. Report of a fatal case and analysis of its confounding factors

This report describes a fatal case of central nervous system pseudallescheriasis. A 32 year old white man presented with headache and meningismus 15 days after nearly drowning in a swine sewage reservoir. Computerised tomography and magnetic resonance imaging of the head revealed multiple brain granulomata, which vanished when steroid and broad spectrum antimicrobial and antifungal agents, in addition to dexamethasone, were started. Cerebrospinal fluid analysis disclosed a neutrophilic meningitis. Treatment with antibiotics and amphotericin B, together with fluconazole and later itraconazole, was ineffective. Miconazole was added through an Ommaya reservoir, but was insufficient to halt the infection. Pseudallescheria boydii was finally isolated and identified in cerebrospinal fluid cultures, a few days before death, three and a half months after the symptoms began. Diagnosis was delayed because of a reduction in the lesions after partial treatment, which prevented a stereotactic biopsy. Physicians should be aware of this condition, and provide prompt stereotactic biopsy. Confirmed cases should perhaps be treated with voriconazole, probably the most effective, currently available treatment for this agent.

Pathogenic molds (including Aspergillus species) in hospital water distribution systems: a 3-year prospective study and clinical implications for patients with hematologic malignancies

The incidence of mold infections in patients with hematologic malignancies continues to increase despite the widespread use of air filtration systems, suggesting the presence of other hospital sources for these molds. Water sources are known to harbor pathogenic molds. We examined samples from water, water surfaces, air, and other environment sources from a bone marrow transplantation unit with optimal air precautions. Molds (Aspergillus species, others) were recovered in 70% of 398 water samples, in 22% of 1311 swabs from plumbing structures and environmental surfaces, and in 83% of 274 indoor air samples. Microscopic examination of the water plumbing lines revealed hyphal forms compatible with molds. Four findings suggest that indoor airborne molds were aerosolized from the water: (1) higher mean airborne concentrations of molds in bathrooms (16.1 colony-forming units [CFU]/m(3)) than in patient rooms (7 CFU/m(3)) and hallways (8.6 CFU/m(3); P =.00005); (2) a strong type and rank correlation between molds isolated from hospital water and those recovered from indoor hospital; (3) lack of seasonal correlation between the airborne mold concentration in outdoor and indoor air; and (4) molecular relatedness between a clinical strain and a water-related strain (previously reported). Hospital water distribution systems may serve as a potential indoor reservoir of Aspergillus and other molds leading to aerosolization of fungal spores and potential exposure for patients.

Case Reports. Infection due to Scedosporium apiospermum in renal transplant recipients: a report of two cases and literature review of central nervous system and cutaneous infections by Pseudallescheria boydii/Sc. apiospermum

Two cases of infections due to Scedosporium apiospermum in renal transplant recipients, one localized in the central nervous system, the other in the skin, are presented, and a literature review of 21 cases of central nervous system and cutaneous infections due to Pseudallescheria boydii/Sc. apiospermum is given.

Pseudallescheria: an underdiagnosed fungus?

Pseudallescheria has been identified as one of the "clinically significant emerging mycoses" but has received little attention in the cytology literature. Recognition of this fungus is of particular importance clinically, because unlike most other fungi (including Aspergillus, with which it is most frequently confused), Pseudallescheria is not effectively treated with amphotericin B, the most frequently and often the only antifungal agent administered. Features helpful in the diagnosis of Pseudallescheria in cytologic material are presented.

Pseudallescheria boydii brain abscess successfully treated with voriconazole and surgical drainage: case report and literature review of central nervous system pseudallescheriasis

Pseudallescheria boydii and its asexual form, Scedosporium apiospermum, are ubiquitous, saprophytic fungi that commonly cause cutaneous infection. However, in certain circumstances, P. boydii can also cause invasive disease, which can involve the central nervous system (CNS). When the CNS becomes involved, treatment is difficult, therapeutic options are limited, and the prognosis is poor. We report a case of Pseudallescheria brain abscess successfully treated with surgical drainage and systemic voriconazole, the first such case to be described in the literature. We also review previously reported cases of CNS pseudallescheriasis and evaluate therapeutic options.

True fungal mycotic aneurysm of the basilar artery: a clinical and surgical dilemma

Mycotic aneurysms of the intracranial circulation of true fungal etiology are extremely rare and are associated with a very high mortality. We report a case of a fatal aneurysm of the basilar artery secondary to Scedosporium apiospermum infection. The medical and surgical treatments are presented to demonstrate the difficulties associated with these lesions.