Cerebral aspergillosis caused by Aspergillus granulosus

Aspergillus granulosus femoral osteomyelitis in a cardiac transplant patient: first reported case and literature review

Aspergillus osteomyelitis is a rare complication of extrapulmonary invasive aspergillosis, which usually presents as spondylodiscitis. The clinical picture is usually paucisymptomatic and of long evolution, which leads to diagnostic difficulties, especially in immunosuppressed patients presenting a delayed systemic host response. We report a case of femoral osteomyelitis caused by Aspergillus granulosus in a heart transplant recipient successfully treated with a combined surgical and antifungal approach. A 65-year-old heart transplant male presented with left knee pain lasting 3 months. X-ray and magnetic resonance imaging identified a lesion with aggressive characteristics at the distal third of the left femur, due to which the patient underwent excisional surgery. Aspergillus granulosus was cultured from the removed material and antifungal treatment with oral isavuconazole was started. Chest imaging excluded pulmonary aspergillosis, while the positron emission tomography/computed tomography (PET/CT) identified a remnant of a prosthetic vascular graft sewn to the proximal third of the right axillary artery, through which a catheter-based micro-axial left ventricular assist device was implanted previously as bridge to transplant therapy. The patient presented a rapid clinical improvement with complete functional recovery following the surgical treatment and the antifungal therapy and finally underwent surgical removal of the residual vascular graft. This is the first reported episode of long bone osteomyelitis due to A. granulosus that occurred in a heart transplant recipient without pulmonary infection and was successfully treated with isavuconazole. The PET/CT was useful in supporting the diagnostic process and follow-up. Cryptic fungal species can cause invasive infections, particularly in immunocompromised patients. Molecular methods are crucial in fungal identification.

Rhino-Orbital-Cerebral Mycosis and Extranodal Natural Killer or/and T-Cell Lymphoma, Nasal Type

Background

Extranodal natural killer/T-cell lymphoma, nasal type is a syndrome of middle face destruction with an association to Epstein-Barr virus. Fungi have been recovered from the diseased tissue now and then but were often seen as a lymphoma-associated secondary infection. However, there are ENKTL-NT cases with the recoveries of fungi and complete recovery with antifungal therapy, which are quite similar to rhino-orbital-cerebral mycosis (ROCM) that often confuses the physicians.

Methods

We searched Medline for English-language manuscripts limited to “human” and “case reports,” “letters,” “reviews,” and “clinical conferences” from 1966 to 2022. We used MeSH terms “lymphoma, extranodal nk-t-cell” [MeSH Terms] or “lethal midline granuloma” [MeSH Terms], in combination with MeSH terms “microbiology” [subheading] or “microbiology” [all fields] or “fungi” [all fields] or “fungi” [MeSH Terms] for ENKTL-NT with infections. We used MeSH terms “Mycoses” in combination with “Nose” [Mesh] OR “Orbital Diseases” [Mesh] for rhino-orbital-cerebral fungal infections.

Results

We appraised 149 included articles and extracted references related to ENKTL-NT and/or ROCM. Themes and subcategories were subsequently derived. Our findings revealed that ROCM and ENKTL-NT are characterized by progressive and destructive ulcers in the midline face or rhino-orbital structures. ROCM is mainly caused by fungi in the order of Mucorales, and ENKTL-NT is usually associated with Epstein-Barr virus and sometimes fungi. Radiologically, both are characterized by non-specific features of sinusitis, soft tissue infection, and necrosis. Pathologically, ROCM and ENKTL-NT share the same characteristics of inflammation, necrosis, and granuloma. ROCM is characterized by the detection of fungi in tissue, while ENKTL-NT is typically positive for NK/T-cell markers and cytotoxic granule-associated proteins, proliferation, and vascular damage of angioinvasion, which could be incited by Mucor irregularis and Rhizopus arrhizus in patients and mice.

Conclusion

ENKTL-NT and ROCM share many similarities in clinical presentations, radiology, and histopathology, and might have the same etiology. This may explain why the two diseases are tangled together in the reported cases, and suggests the role that the fungi may play in the development of these ENKTL-NT/ROCM diseases. The reason why ENKTL-NT and ROCM are sometimes confused is that the main pathogens of ROCM, Mucor irregularis and Rhizopus arrhizus, are the fungal causative agents of ENKTL-NT.

Invasive Aspergillosis Due to Aspergillus Section Usti: A Multicenter Retrospective Study

BACKGROUND

Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergillosis (IA). This multicenter study describes the epidemiology and outcome of A. ustus infections.

METHODS

Patients with A. ustus isolated from any clinical specimen were retrospectively identified in 22 hospitals from 8 countries. When available, isolates were sent for species identification (BenA/CaM sequencing) and antifungal susceptibility testing. Additional cases were identified by review of the literature. Cases were classified as proven/probable IA or no infection, according to standard international criteria.

RESULTS

Clinical report forms were obtained for 90 patients, of whom 27 had proven/probable IA. An additional 45 cases were identified from literature review for a total of 72 cases of proven/probable IA. Hematopoietic cell and solid-organ transplant recipients accounted for 47% and 33% cases, respectively. Only 8% patients were neutropenic at time of diagnosis. Ongoing antimold prophylaxis was present in 47% of cases. Pulmonary IA represented 67% of cases. Primary or secondary extrapulmonary sites of infection were observed in 46% of cases, with skin being affected in 28% of cases. Multiple antifungal drugs were used (consecutively or in combination) in 67% of cases. The 24-week mortality rate was 58%. A. calidoustus was the most frequent causal agent. Minimal inhibitory concentrations encompassing 90% isolates (MIC90) were 1, 8, >16, and 4 µg/mL for amphotericin B, voriconazole, posaconazole, and isavuconazole, respectively.

CONCLUSIONS

Aspergillus ustus IA mainly occurred in nonneutropenic transplant patients and was frequently associated with extrapulmonary sites of infection. Mortality rate was high and optimal antifungal therapy remains to be defined.

Taxonomy Driven Discovery of Polyketides from Aspergillus californicus

Five new polyketides were isolated from the rare filamentous fungus Aspergillus californicus IBT 16748 including calidiol A (1); three phthalide derivatives califuranones A₁, A₂, and B (2-4); and a pair of enantiomers (-)-calitetralintriol A (-5) and (+)-calitetralintriol A (+5) together with four known metabolites (6-9). The structures of the new products were established by extensive spectroscopic analyses including HRMS and 1D and 2D NMR. The absolute configurations of two diastereomers 2 and 3 and the enantiomers (-5) and (+5) were assigned by comparing their experimental and calculated ECD data, whereas the absolute configuration of 4 was proposed by analogy. Compound 1 showed moderate activity against methicillin-resistant Staphylococcus aureus.

Impact of Surgical and Medical Treatment on Survival of Patients with Cerebral Aspergillosis: Systematic Review of the Literature

OBJECTIVE

Cerebral aspergillosis carries a high mortality. Rapid diagnosis and treatment can increase survival, but symptoms and imaging findings are nonspecific. The literature on cerebral aspergillosis consists mostly of case reports and case series and lacks large-scale review of data.

METHODS

We performed a review of the literature using PubMed in March 2019. We recorded the year of publication, age and sex of patients, neurosurgical involvement, the antifungals administered, use of intrathecal antifungals, and the outcome of patients. The relationships among variables were tested using bivariant statics and linear regression.

RESULTS

A total of 324 studies met the eligibility criteria, and 198 studies including 248 patients were included. Surgical resection (odds ratio [OR], 0.45; 95% confidence interval [CI], 0.25-0.80; P < 0.01) and administration of voriconazole (OR, 0.32; 95% CI, 0.18-0.55; P < 0.001) or itraconazole (OR, 0.36; 95% CI, 0.16-0.72; P < 0.001) were shown to be significantly associated with survival.

CONCLUSIONS

Given the significant survival benefits for patients who received voriconazole and surgical intervention, we suggest early antifungal medical treatment and resection.

New species in Aspergillus section Usti and an overview of Aspergillus section Cavernicolarum

Aspergillus sections Usti and Cavernicolarum are accommodated in the subgenus Nidulantes. In the present study, a polyphasic approach using morphology and multi-gene phylogeny was applied to investigate the taxonomy of these two sections. Based on the phylogenetic analysis, Aspergillus section Usti includes 25 species, which can be assigned to four series: Calidousti, Deflecti, Monodiorum and Usti. Aspergillus sigarelli is newly described in this section and this species was isolated from a cigarette from PR China and belongs to series Calidousti. It is clearly distinct from other members in this series based on ITS, BenA, CaM and RPB2 sequences. Aspergillus section Usti members like A. calidoustus and A. granulosus are important opportunistic pathogens, it is speculative that more pathogenetic species will be found by using polyphasic taxonomy approaches. Aspergillus section Cavernicolarum includes five species, the growth rates on agar media and size and ornamentation of conidia are important characters for differentiating species in section Cavernicolarum.

Clinical Relevance and Characteristics of Aspergillus calidoustus and Other Aspergillus Species of Section Usti

The Aspergilli of section Usti (group ustus) are represented by over 20 species, of which Aspergillus calidoustus is the most relevant human pathogen. Invasive aspergillosis (IA) caused by these fungi is rare but could represent an emerging issue among the expanding population of patients with long-term immunosuppression receiving antifungal prophylaxis. Clinicians should be aware of this unusual type of IA, which often exhibits distinct clinical features, such as an insidious and prolonged course and a high occurrence of extra-pulmonary manifestations, such as skin/soft tissue or brain lesions. Moreover, these Aspergillus spp. pose a therapeutic challenge because of their decreased susceptibility to azole drugs. In this review, we outline the microbiological and clinical characteristics of IA due to Aspergillus spp. of section Usti and discuss the therapeutic options.

Aspergillus pseudodeflectus: a new human pathogen in liver transplant patients

BACKGROUND

Liver transplant recipients are at high risk of developing invasive aspergillosis and in particular by Aspergillus fumigatus which is the most commonly encountered species in this population. Other non-fumigatus Aspergillus species with reduced susceptibility to antifungal drugs can also be involved. Accurate identification associated to antifungal susceptibility testing is essential for therapy adjustment. We report a case of invasive pulmonary aspergillosis due to Aspergillus pseudodeflectus in a liver transplant recipient. To our knowledge, this is the first reported case of invasive aspergillosis due to this species with a reduced susceptibility to azoles.

CASE PRESENTATION

A 64 year-old woman with drug-induced fulminant hepatitis underwent liver transplantation. Prophylactic treatment with caspofungin was introduced due to aspergillosis risk factors consisting in hemodialysis and fulminant hepatitis. Six weeks after transplantation, CT scan showed a right pulmonary opacity associated with an increase of galactomannan (index 5.4). Culture of BAL grew with several colonies of Aspergillus sp. The diagnosis of invasive aspergillosis was probable according to the EORTC criteria. The antifungal susceptibility tests (Etest®) revealed low MICs to echinocandins and amphotericin B) but high MICs to azoles. After these results, voriconazole was switched to liposomal amphotericin B. The patient died one month after diagnosis from a refractory septic shock with multiple organ failure. A molecular identification of isolate, based on partial β-tubulin and calmodulin genes, was performed and identified A. pseudodeflectus.

CONCLUSIONS

Our case raises the question of pathogenicity of this species, which belongs to Aspergillus section Usti and is genetically and morphologically very close to Aspergillus calidoustus that was previously reported in human transplant recipients.

Successful treatment of Aspergillus ventriculitis through voriconazole adaptive pharmacotherapy, immunomodulation, and therapeutic monitoring of cerebrospinal fluid (1→3)-β-D-glucan

Aspergillus ventriculitis is an uncommon but often fatal form of invasive aspergillosis of the central nervous system (CNS). As little is known about the diagnosis, treatment, and outcome of this potentially lethal infection, we report the strategies used to successfully treat Aspergillus ventriculitis complicating a pineal and pituitary germinoma with emphasis on the critical role of adaptive pharmacotherapy of voriconazole and serial monitoring of (1→3)-β-D-glucan in cerebrospinal fluid. We describe several rationally based therapeutic modalities, including adaptive pharmacotherapy, combination therapy, sargramostim-based immunomodulation, and biomarker-based therapeutic monitoring of the CNS compartment. Through these strategies, our patient remains in remission from both his germinoma and Aspergillus ventriculitis making him one of the few survivors of Aspergillus ventriculitis.

Previously unknown species of Aspergillus

The use of multi-locus DNA sequence analysis has led to the description of previously unknown 'cryptic' Aspergillus species, whereas classical morphology-based identification of Aspergillus remains limited to the section or species-complex level. The current literature highlights two main features concerning these 'cryptic' Aspergillus species. First, the prevalence of such species in clinical samples is relatively high compared with emergent filamentous fungal taxa such as Mucorales, Scedosporium or Fusarium. Second, it is clearly important to identify these species in the clinical laboratory because of the high frequency of antifungal drug-resistant isolates of such Aspergillus species. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently been shown to enable the identification of filamentous fungi with an accuracy similar to that of DNA sequence-based methods. As MALDI-TOF MS is well suited to the routine clinical laboratory workflow, it facilitates the identification of these 'cryptic' Aspergillus species at the routine mycology bench. The rapid establishment of enhanced filamentous fungi identification facilities will lead to a better understanding of the epidemiology and clinical importance of these emerging Aspergillus species. Based on routine MALDI-TOF MS-based identification results, we provide original insights into the key interpretation issues of a positive Aspergillus culture from a clinical sample. Which ubiquitous species that are frequently isolated from air samples are rarely involved in human invasive disease? Can both the species and the type of biological sample indicate Aspergillus carriage, colonization or infection in a patient? Highly accurate routine filamentous fungi identification is central to enhance the understanding of these previously unknown Aspergillus species, with a vital impact on further improved patient care.

A universal DNA extraction and PCR amplification method for fungal rDNA sequence-based identification

Accurate identification of fungal pathogens using a sequence-based approach requires an extraction method that yields template DNA pure enough for polymerase chain reaction (PCR) or other types of amplification. Therefore, the objective of this study was to develop and standardise a rapid, inexpensive DNA extraction protocol applicable to the major fungal phyla, which would yield sufficient template DNA pure enough for PCR and sequencing. A total of 519 clinical and culture collection strains, comprised of both yeast and filamentous fungi, were prepared using our extraction method to determine its applicability for PCR, which targeted the ITS and D1/D2 regions in a single PCR amplicon. All templates were successfully amplified and found to yield the correct strain identification when sequenced. This protocol could be completed in approximately 30 min and utilised a combination of physical and chemical extraction methods but did not require organic solvents nor ethanol precipitation. The method reduces the number of tube manipulations and yielded suitable template DNA for PCR amplification from all phyla that were tested.

Aspergillus meningitis: a rare clinical manifestation of central nervous system aspergillosis. Case report and review of 92 cases

OBJECTIVES

To describe the pathogenesis, clinical presentation, cerebrospinal fluid findings and outcome of Aspergillus meningitis, meningoencephalitis and arachnoiditis.

METHODS

A case of Aspergillus meningitis is described. A comprehensive review of the English-language literature was conducted to identify all reported cases of Aspergillus meningitis described between January 1973 and December 2011.

RESULTS

Ninety-three cases (including the one described herein) of Aspergillus meningitis were identified. Fifty-two (55.9%) were in individuals without any predisposing factor or known causes of immunosuppression. Acute and chronic meningitis was diagnosed in 65.6% of patients and meningoencephalitis in 24.7% of them with the remaining presenting with spinal arachnoiditis and ventriculitis. Cerebrospinal fluid cultures for Aspergillus spp. were positive in about 31% of cases and the galactomannan antigen test in 87%. Diagnosis during life was achieved in 52 patients (55.9%) with a case fatality rate of 50%. The overall case fatality rate was 72.1%.

CONCLUSIONS

Aspergillus meningitis may occur in both immunocompetent and immunocompromised patients and run an acute or chronic course. The findings of this systematic review extend the information on this life-threatening infection and could assist physicians in achieving an improved outcome.

Central nervous system aspergillosis: a series of 14 cases from a general hospital and review of 123 cases from the literature

Central nervous system (CNS) aspergillosis is a highly fatal infection. We review the clinical presentation, diagnosis, and outcome of this infection and present a case series of 14 consecutive patients with CNS aspergillosis admitted to Massachusetts General Hospital (MGH) from 2000 to 2011. We also review 123 cases reported in the literature during that time. We included only proven CNS aspergillosis cases conforming to the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) definitions of invasive fungal infections. In the MGH case series, neutropenia, hematologic malignancies, autoimmune diseases requiring steroid treatment, and solid organ transplantation were the predominant comorbid conditions. Notably, all MGH patients were immunosuppressed, and more than half (n = 8) had a history of previous brain injury, unrelated to their index hospitalization. For most MGH patients (11 of 14), the lung was the primary focus of aspergillosis, while 2 had paranasal sinus involvement, and 1 had primary Aspergillus discitis. Among reported cases, paranasal sinuses (27.6%) and the lung (26.8%) were the primary foci of infection, whereas 22% of those cases had no obvious primary organ involvement. Although a selection bias should be considered, especially among published cases, our findings suggest that patients who underwent neurosurgery had improved survival, with MGH and literature patients having 25% and 28.6% mortality, respectively, compared to 100% and 60.4%, respectively, among patients who received only medical treatment. Although this was not the case among MGH patients, CNS aspergillosis can affect patients without significant immune suppression, as indicated by the high number of reported immunocompetent cases. In conclusion, mortality among CNS aspergillosis patients remains high, and the infection may be more common among patients with previous brain pathology. When indicated, neurosurgical procedures may improve prognosis.