Rapid identification of fungi in culture-negative clinical blood and respiratory samples by DNA sequence analyses

Challenges in Management of Uncommon Otologic Fungal Disease - a Case Series and Review of Literature

The purpose of this study is to describe challenges in diagnosis and treatment of otologic fungal infections.; 2) Methods: Case series and literature review 3) Results: Three patients treated at Louisiana State University Health Sciences Center - Shreveport between November 2020 - November 2023 were identified with complicated fungal otitis externa requiring detailed radiologic and histopathologic workup to aid in diagnosis and management. 4) Conclusion: Diagnosis of otologic fungal infection is often complex due to similar presentation of more common pathogens, overlapping features among common fungal specimens, and limitations of available diagnostic methods. Patient factors, including diabetes with poor glycemic control, may further complicate this challenging disease. High index of clinical suspicion, collaboration between multidisciplinary teams is essential to differentiate between common and uncommon fungal ear infections. A combination of mechanical debridement, topical and/or systemic therapy, and longitudinal follow-up with otolaryngology and infectious disease teams is required for successful treatment.

Accurate diagnosis of bronchopulmonary Talaromyces marneffei infection in an anti-IFN-γ autoantibodies positive patient assisted by endobronchial ultrasound-guided TBNA and mNGS: a case report

RATIONALE

T. marneffei is opportunistic and dimorphic fungus, which can cause systemic mycosis in human beings. It's being difficult to obtain histopathological or microbiological evidence in T. marneffei infection. We reported a rare non-HIV case of T. marneffei infection of bronchopulmonary and mediastinal lymph nodes which was diagnosed by EBUS-TBNA combined with mNGS. The high titer of anti-IFN-γ autoantibodies in serum was probably the cause of T. marneffei infection,which has yet to be fully known.

PATIENT CONCERNS

A 56-year-old Chinese man presented with a 5-month history of intermittent low or high fever and dry cough, followed by fatigue, night sweating, and chest pain when coughing. A large hilar lesion in the left lung and multiple mediastinal lymph node enlargements were found on his chest CT scan.

DIAGNOSES

The patient received EBUS-TBNA of hilar tissue and lymph node biopsy for mNGS at the second Ultrasonic bronchoscopy. No fungal hyphae or spores were found in the histopathology. There were high sequencing reads of T. marneffei in samples of lymph node fluid and bronchogenesis tissue detected by mNGS. His plasma anti-IFN-γ autoantibodies level was positive with a high titer at 1:2500↑.

INTERVENTION

The patient went through atrial fibrillation at the first dose of amphotericin B liposomes and treated with voriconazole later.

OUTCOMES

His fever, cough and dyspnea quickly disappeared since the fourth day of treatment. After six months, there was not any focus in his chest CT scans. But his plasma anti-IFN-γ autoantibodies remained unchanged.

LESSONS

Complementing the traditional laboratory and bronchoscopy, mNGS combined with EBUS-TBNA facilitate rapid and precise diagnosis of bronchopulmonary mediastinal lymph nodes T. marneffei infection. Clinicians should be aware of anti-INF-γ autoantibodies in opportunistic infections of non-HIV patients.

Updated Perspectives on the Diagnosis and Management of Onychomycosis

Onychomycosis is the most common nail disease encountered in clinical practice and can cause pain, difficulty with ambulation, and psycho-social problems. A thorough history and physical examination, including dermoscopy, should be performed for each patient presenting with nail findings suggestive of onychomycosis. Several approaches are available for definitive diagnostic testing, including potassium hydroxide and microscopy, fungal culture, histopathology, polymerase chain reaction, or a combination of techniques. Confirmatory testing should be performed for each patient prior to initiating any antifungal therapies. There are several different therapeutic options available, including oral and topical medications as well as device-based treatments. Oral antifungals are generally recommended for moderate to severe onychomycosis and have higher cure rates, while topical antifungals are recommended for mild to moderate disease and have more favorable safety profiles. Oral terbinafine, itraconazole, and griseofulvin and topical ciclopirox 8% nail lacquer, efinaconazole 10% solution, and tavaborole 5% solution are approved by the Food and Drug Administration for treatment of onychomycosis in the United States and amorolfine 5% nail lacquer is approved in Europe. Laser treatment is approved in the United States for temporary increases in clear nail, but clinical results are suboptimal. Oral fluconazole is not approved in the United States for onychomycosis treatment, but is frequently used off-label with good efficacy. Several novel oral, topical, and over-the-counter therapies are currently under investigation. Physicians should consider the disease severity, infecting pathogen, medication safety, efficacy and cost, and patient age, comorbidities, medication history, and likelihood of compliance when determining management plans. Onychomycosis is a chronic disease with high recurrence rates and patients should be counseled on an appropriate plan to minimize recurrence risk following effective antifungal therapy.

Characterization and phylogeny of fungi isolated from industrial wastewater using multiple genes

The aim of this study was the isolation and molecular characterization of fungi from untreated refinery effluent by using multiple conserved genes. The Fungi isolated were characterized based on PCR amplification and genomic sequencing of the internal transcribed spacer region (ITS), partial β-tubulin (BenA), calmodulin (CaM), and RNA polymerase second large subunit (RPB2) genes, along with morphological characterization. The obtained sequences were subjected to BLAST analysis and the corresponding fungal isolates were assigned species names after comparison with representative sequences available in GenBank. Fifteen (15) Fungi species belonging to four genera of Aspergillus, Penicillium, Fusarium, and Trichoderma with Aspergillus as the predominant genus were identified. Therefore these genes should be used as molecular markers for species level identification of fungi (especially Aspergillus and Penicillium as proven in this study.

False negative diagnostic errors with polymerase chain reaction for the detection of cryptococcal meningoencephalitis

The accuracy of the BioFire FilmArray Meningitis/Encephalitis (ME) panel for the identification of Cryptococcus has recently been called into question. The primary objective of this study was to assess the agreement between the BioFire ME polymerase chain reaction (PCR) and other markers of cryptococcal infection. This retrospective review identified five patients with cryptococcal meningoencephalitis, 4 of whom had a negative ME panel for Cryptococcus. All five cases had positive serum cryptococcal antigens, and three of five had a positive cerebrospinal fluid (CSF) culture for Cryptococcus. The BioFire ME panel does not appear to be reliable for ruling out Cryptococcus meningoencephalitis; multiple testing methods are recommended.

Successful allogeneic stem cell transplantation in a case with acute myeloid leukemia and invasive Schizophyllum commune rhinosinusitis

Schizophyllum commune, a basidiomycete fungus, is a quite rare cause of invasive sinusitis for which no standard treatment has yet been established. We report herein a 59-year-old woman who developed S. commune rhinosinusitis after remission induction chemotherapy for her acute myeloid leukemia. No causative microorganisms were identified in the sinus lavage fluid culture, whereas nucleotide sequencing of the internal transcribed spacer region using endoscopic sinus biopsy specimen could confirm the pathogen as S. commune. Liposomal amphotericin B and voriconazole (VRCZ) treatment ameliorated both her clinical symptoms and laboratory findings. The patient was successfully treated with allogeneic stem cell transplantation, under continuous VRCZ administration, without aggravation of S. commune sinusitis. Molecular diagnosis and prompt intervention with suitable antifungal drugs may be crucial to manage this rare infectious complication.

Oral Probiotics Alter Healthy Feline Respiratory Microbiota

Probiotics have been advocated as a novel therapeutic approach to respiratory disease, but knowledge of how oral administration of probiotics influences the respiratory microbiota is needed. Using 16S rRNA amplicon sequencing of bacterial DNA our objective was to determine whether oral probiotics changed the composition of the upper and lower airway, rectal, and blood microbiota. We hypothesized that oral probiotics would modulate the respiratory microbiota in healthy cats, demonstrated by the detection and/or increased relative abundance of the probiotic bacterial species and altered composition of the microbial population in the respiratory tract. Six healthy young research cats had oropharyngeal (OP), bronchoalveolar lavage fluid (BALF), rectal, and blood samples collected at baseline and 4 weeks after receiving oral probiotics. 16S rRNA gene amplicon libraries were sequenced, and coverage, richness, and relative abundance of representative operational taxonomic units (OTUs) were determined. Hierarchical and principal component analyses (PCA) demonstrated relatedness of samples. Mean microbial richness significantly increased only in the upper and lower airways. The number of probiotic OTUs (out of 5 total) that significantly increased in relative abundance vs. baseline was 5 in OP, 3 in BAL and 2 in feces. Using hierarchical clustering, BALF and blood samples grouped together after probiotic administration, and PERMANOVA supported that these two sites underwent significant changes in microbial composition. PERMANOVA revealed that OP and rectal samples had microbial population compositions that did not significantly change. These findings were visualized via PCA, which revealed distinct microbiomes in each site; samples clustered more tightly at baseline and had more variation after probiotic administration. This is the first study describing the effect of oral probiotics on the respiratory microbiota via detection of probiotic species in the airways. Finding bacterial species present in the oral probiotics in the upper and lower airways provides pilot data suggesting that oral probiotics could serve as a tool to target dysbiosis occurring in inflammatory airway diseases such as feline asthma, a disease in which cats serve as an important comparative and translational model for humans.