A single aspergillus fumigatus intracranial abscess in an immunocompetent patient with parietal lobe tumorectomy

Rare case of aspergillus brain abscess in an immunocompromised patient

We present a case of aspergillus brain abscess in a 48‐year‐old woman with a history of kidney transplantation and no underlying central nervous system (CNS) disease. Follow‐up of the patient for 4 years shows normal findings. Early diagnosis and aggressive treatment could improve the prognosis of this fatal complication.

Metagenomic Next-Generation Sequencing of Cerebrospinal Fluid for the Diagnosis of Cerebral Aspergillosis

Purpose: Cerebral aspergillosis (CA) is a rare but often fatal, difficult-to-diagnose, opportunistic infection. The utility of metagenomic next-generation sequencing (mNGS) for diagnosis of CA is unclear. We evaluated the usefulness of mNGS of the cerebrospinal fluid (CSF) for the diagnosis of CA. Methods: This prospective study involved seven consecutive patients with confirmed CA in whom CSF mNGS was performed. Serum (1→3)-β-D-glucan and galactomannan levels were determined, and histopathological examination and mNGS of the CSF were conducted. CSF specimens from three non-infected patients were used as positive controls. Results: mNGS of the CSF was positive in six of the seven confirmed CA cases (85.71% sensitivity). In the cryptococcal meningitis group (control), mNGS of the CSF was positive for Aspergillus in two patients (84.62% specificity). The positive likelihood ratio, negative likelihood ratio, and Youden's index of mNGS for CA in the CSF were 5.565, 0.169, and 0.7, respectively. Among the six mNGS-positive cases, more than two Aspergillus species were found in four (4/6, 66.67%). In the positive controls, the addition of one A. fumigatus spore yielded a standardised species-specific read number (SDSSRN) of 25.45 by mNGS; the detection rate would be 0.98 if SDSSRN was 2. Conclusion: mNGS facilitates the diagnosis of CA and may reduce the need for cerebral biopsy in patients with suspected CA. Trial Registration Number: Chinese Clinical Trial Registry, ChiCTR1800020442.

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.

Metagenomic Next-Generation Sequencing for Diagnosis of Infectious Encephalitis and Meningitis: A Large, Prospective Case Series of 213 Patients

Purpose: We assessed the performance of metagenomic next-generation sequencing (mNGS) in the diagnosis of infectious encephalitis and meningitis.

Methods: This was a prospective multicenter study. Cerebrospinal fluid samples from patients with viral encephalitis and/or meningitis, tuberculous meningitis, bacterial meningitis, fungal meningitis, and non-central nervous system (CNS) infections were subjected to mNGS.

Results: In total, 213 patients with infectious and non-infectious CNS diseases were finally enrolled from November 2016 to May 2019; the mNGS-positive detection rate of definite CNS infections was 57.0%. At a species-specific read number (SSRN) ≥2, mNGS performance in the diagnosis of definite viral encephalitis and/or meningitis was optimal (area under the curve [AUC] = 0.659, 95% confidence interval [CI] = 0.566–0.751); the positivity rate was 42.6%. At a genus-specific read number ≥1, mNGS performance in the diagnosis of tuberculous meningitis (definite or probable) was optimal (AUC=0.619, 95% CI=0.516–0.721); the positivity rate was 27.3%. At SSRNs ≥5 or 10, the diagnostic performance was optimal for definite bacterial meningitis (AUC=0.846, 95% CI = 0.711–0.981); the sensitivity was 73.3%. The sensitivities of mNGS (at SSRN ≥2) in the diagnosis of cryptococcal meningitis and cerebral aspergillosis were 76.92 and 80%, respectively.

Conclusion: mNGS of cerebrospinal fluid effectively identifies pathogens causing infectious CNS diseases. mNGS should be used in conjunction with conventional microbiological testing.

Trial Registration: Chinese Clinical Trial Registry, ChiCTR1800020442.

Comparative Pathomorphological, Mycological and Molecular Examination of Turkey Poults with Different Immunological Status Experimentally Infected with Aspergillus fumigatus

The aim of this study was to determine the pathological, mycological and molecular findings in turkey poults with different immunological status experimentally infected with Aspergillus fumigatus. The investigation was carried out 1, 3, 7, 14 and 21 days after intratracheal inoculation of 5.056×107 spores of A. fumigatus to 14-day-old turkey poults in group G-1, as well as to turkey poults in group G-2 which were treated prior to infection with dexamethasone. A. fumigatus was isolated on day 1 p.i. in both groups, but the number of positive samples was bigger in group G-1. A. fumigatus was isolated from the respiratory organs of group G-1as early as on day 1 and 3 p.i. in 4 out of 12 examined specimens (33%). On day 7 p.i. A. fumigatus was possible to isolate from the respiratory organs of 50% of infected birds, on day 14 in 83.33% and on day 21 p.i. A. fumigatus was isolated in 6 out of 6 sacrificed turkey poults (100%). In dexamethasone-treated group A. fumigatus isolates from the respiratory organs on day 1 and 3 p.i. were same as in group G-1, whereas on days 7 and 14 p.i. the number of turkey poults positive to A. fumigatus increased in comparison with the untreated G-1 group. The histopathological lesions in turkey poults treated with dexamethasone developed earlier, were more intensive and extensive. The mycological and nested PCR results revealed a higher number of samples positive for the presence of A. fumigatus DNA in the group G-2, pretreated with dexamethasone.

In vitro activity of chlorogenic acid against Aspergillus fumigatus biofilm and gliotoxin production

Aspergillus (A.) fumigatus, one of the most common causes of life-threatening fungal infections in immunocompromised patients, shows resistance to antifungal agents as has a high propensity to forming a biofilm. The present study aimed to investigate the effects of chlorogenic acid (CRA) on A. fumigatus biofilm formation and integrity. Confocal laser scanning microscopy was performed to determine the inhibitory effects of CRA against A. fumigatus biofilm formation. Transmission electron microscopy was performed to investigate the ultrastructural changes of A. fumigatus biofilm after CRA exposure. High-performance liquid chromatography and reverse-transcription quantitative PCR were performed to determine the expression of gliotoxin production in biofilm culture. The results showed that CRA at sub-minimum inhibitory concentrations inhibited A. fumigatus biofilm formation. In addition, CRA could decreased the gliotoxin production in the biofilm culture supernatant through inhibiting the expression of master genes involved in gliotoxin biosynthesis. The present study provided useful information for the development of novel strategies to reduce the incidence of A. fumigatus biofilm-associated diseases.