Frequency of fungal agents identified in sinus samples from patients with clinically suspected rhinosinusitis

Post-transplant Schizophyllum commune abscess in a pediatric patient with chronic granulomatous disease

Schizophyllum commune is a widely distributed basidiomycete fungus that occasionally causes sinusitis or allergic bronchopulmonary mycosis. The invasive infection mostly occurs in immunocompromised adults. The number of reports on S. commune infection have increased in this decade due to the expansion of diagnostic techniques and awareness in clinical practice. However, S.commune infection in patients with primary immunodeficiencies has not been reported yet. Here, we described S. commune-abscesses developed in the brain and lung of a boy with chronic granulomatous disease (CGD) after allogenic hematopoietic cell transplantation (HCT). A 12-year-old CGD patient developed febrile neutropenia from day 4 after HCT, followed by chest pain on day 23. He had no obvious infection before HCT. Diagnostic imaging revealed disseminated lung and brain abscesses. He received administration of voriconazole, and his symptoms improved after engraftment. Chronic administration of voriconazole had also a favorable therapeutic response to brain lesion. A part of the fungus ball exhaled by the patient was cultured to develop a filamentous fungus. S. commune was identified by the analysis of the 28S rRNA gene. The catalase test was positive for S. commune, indicating that S. commune had virulence in this patient with CGD. The assessment of specific-IgG to S. commune suggested peri-transplant infection, although colonization was not excluded. This rare pediatric case of S. commune infection highlights that CGD patients are vulnerable to invasive infection, especially when undergoing HCT.

The nonlinear association between albumin levels and risk of noninvasive fungal rhinosinusitis

PURPOSE

The preoperative diagnosis of noninvasive fungal rhinosinusitis (NIFRS) is inaccurate, and biomarkers to assist the diagnosis are urgently needed. We aimed to evaluate the relationship between albumin levels and NIFRS to assist in early diagnosis.

METHODS

Patients with NIFRS and chronic sinusitis were enrolled in this study. Appropriate statistical methods were used to determine whether there was a statistical difference between the groups. Subgroup analysis was performed to investigate the relationship between albumin levels and NIFRS, and a generalised additive model (GAM) was used to perform nonlinear relationships.

RESULTS

A total of 620 patients were included, including 240 patients with NIFRS. A close relationship was found between albumin levels and NIFRS (P < 0.0001), and the low albumin group was associated with a higher incidence of NIFRS, which was reduced by 60 and 70% in the middle and high albumin groups, respectively. The subgroup analysis also demonstrated an association between albumin levels and NIFRS, except in patients with an alcohol history (P = 0.0665). Interestingly, a nonlinear relationship is observed according to the adjusted GAM. The inflection point was set at 37.0 g/L. A negative correlation was observed among patients with albumin > 37.0 g/L. When the albumin count was <37.0 g/L, the Y value obviously increased and was saturated at 70%, with no further significant increase.

CONCLUSION

Albumin levels were significantly negatively correlated with the incidence of NIFRS, and the incidence increased markedly among patients with albumin < 37.0 g/L.

Nested PCR for the detection of Aspergillus species in maxillary sinus samples of patients with chronic sinusitis

BACKGROUND

Fungal rhinosinusitis has become an increasingly recognized disease, being Aspergillus species responsible for most of the cases. Its diagnosis is quite difficult because of the non-specific symptoms and low sensitivity of the current diagnostic methods.

AIMS

An Aspergillus-specific nested polymerase chain reaction (PCR) assay using biopsy specimens taken from the maxillary sinuses was performed in order to assess its usefulness. Conventional diagnostic methods (histology and culture) were also carried out.

METHODS

A case-control study was performed in the Institute of Stomatology, Jagiellonian University in Kraków, between 2011 and 2014. The case group consisted of 21 patients with suspected rhinosinusal mycetoma while the control group included 46 patients with no suspicion of fungal rhinosinusitis. The two-step PCR assay amplified an Aspergillus specific portion of the 18S rRNA gene. Interval estimation of sensitivity, specificity, positive (PPV) and negative (NPV) predictive values were calculated to assess the diagnostic test performance. The agreement between the PCR and the other tests was evaluated using the Kappa coefficient (k).

RESULTS

Ninety percent of the samples obtained from patients diagnosed with mycetoma yielded positive PCR results. The PCR showed almost perfect concordance with histology (k=0.88). Sensitivity, specificity, PPV and NPV estimates were 90%; 95% CI: (55.5-99.7%), 98.3%; 95% CI: (90.9-100%), 90%; 95% CI: (55.5-99.7%) and 98.3%; 95% CI: (90.9-100%), respectively. One clinical sample showed growth of Aspergillus fumigatus and positive PCR despite the negative histological examination.

CONCLUSIONS

Nested PCR assay is a promising diagnostic tool to evaluate the presence of Aspergillus in the tissue of maxillary sinus from patients with suspicion of sinus aspergillosis.

[Allergic fungal rhinosinusitis: A diagnosis to evoke]

Among fungal infections of the nasal sinuses, allergic fungal rhinosinusitis is a recently described, relatively rare and little known pathology. Its diagnosis is based on: clinical criteria (it occurs in young immunocompetent patients, often associated with bilateral nasosinusal polyposis); pathological criteria (allergic mucin: eosinophilic mucus without invasion of the sinusal mucosa and observation of fungal hyphae on surgical samples); biological criteria (hypereosinophilia, total and specific antifungal IgE); and radiological criteria. The combination of tomodensitometry (heterogeneous hyperdense and diffuse filling of nasosinusal cavities with expanded borders and a distended appearance of the bony wall), and MRI scan (extensive character and lesional signal [hypo and asignal T1 and T2], and cerebriform aspect of the fungal process) strongly suggests the diagnosis. It is important to distinguish the most typical forms, as well as unusual forms of allergic fungal rhinosinusitis. Main differential diagnoses are represented by other forms of fungal nasosinusal infections with different treatment and prognosis.

Direct identification of molds by sequence analysis in fungal chronic rhinosinusitis

Fungi are widely implicated in chronic rhinosinusitis. Direct microscopic examination (DME) is used to confirm the biological diagnosis of fungal rhinosinusitis (FRS). Diagnostic sensitivity of DME is better than culture, however DME does not allow fungal species identification. In this study, we included 54 sinus samples demonstrating hyphae on DME. Direct sequencing was compared to culture for the identification of the fungal species. Sequence analysis identified fungi in 81.5% of cases while culture was positive in only 31.5%. The most common genus was Aspergillus and the identified species belonged to section Fumigati or to section Flavi. Among other fungi identified by sequence analysis, Schizophyllum commune was present in three samples attesting to the importance of this Basidiomycetes in FRS. Our results clearly demonstrate the superiority of sequencing compared to culture when performed on specimens with hyphal elements at DME, and contributes to the epidemiological knowledge of fungi involved in FRS.

Schizophyllum radiatum, an Emerging Fungus from Human Respiratory Tract

Schizophyllum is an important genus of basidiomycetes that, apart from being of genetic and biotechnological interest, is also reported to be a plant and animal pathogen. Schizophyllum commune is the best-known species and the only one reported from clinical specimens thus far, being recovered mainly from the respiratory tract. The aim of this study was to determine the species diversity of 23 clinical isolates of Schizophyllum from the United States using multilocus phylogenetic analysis and their in vitro susceptibilities to six drugs. The markers used for sequencing were the internal transcribed spacer (ITS), a portion of the nuclear large subunit (LSU) of ribosomal DNA, the RNA polymerase II second-largest subunit (RPB2), and the translation elongation factor 1α (EF-1α) gene. The analyses revealed that 22 of the clinical isolates were in the Schizophyllum radiatum clade with high support values and 1 isolate was in the S. commune clade. This is the first report of this species in clinical samples. The two species mentioned above showed very similar morphological features in culture (i.e., white, cottony, unsporulated colonies composed of hyphae with clamp connections), making morphological discrimination between the two impossible. An epitype is designed for S. radiatum, and its sequences have been deposited in GenBank. The antifungal that showed the greatest in vitro activity against the strains tested was shown to be amphotericin B. In general, the strains of S. radiatum showed higher MICs than S. commune.