Nocardiosis in the Illawarra-Shoalhaven region from 2010 to 2019.

The UK SMI B1 protocol including a single Sabouraud dextrose agar with chloramphenicol (SABC) incubated at 37°C for 48 hours was compared to a standard fungal-specific culture method using two SABC agar plates incubated at 28°C and 37°C for 2 weeks with an extra Candida chromogenic agar incubated at 37°C for 5 days.

 Altogether, 304 individual patient ear swabs were prospectively examined.

The standard protocol identified seven compared to 17 species using the fungal-specific protocol. A total of 93 fungal isolates were recovered; nine different yeasts and eight filamentous fungal species.

Candida parapsilosis (38/304; 13%), C. albicans (10/304; 3%) and C. orthopsilosis (6/304; 2%) were common yeast species. Aspergillus niger complex (16/304; 5%) was the most common mold, followed by A. fumigatus complex (3/304; 1%).

 Our results suggest that the UK SMI B1 media and procedures are inadequate to detect all fungal agents causing otomycosis.

Fungal-specific culture protocols increase the recovery rate and diversity of fungal pathogens isolated from ear samples.

1. Active surveillance for methicillin-resistant Staphylococcus aureus (MRSA) is a component of our neonatal intensive care unit (NICU) infection prevention efforts.
2. Recent atypical trends prompted review of 42 suspected MRSA isolates. Species identification was confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and methicillin resistance was reevaluated by PBP2a lateral flow assay, cefoxitin/oxacillin susceptibility testing, mecA and mecC PCR, and six commercially available MRSA detection agars.
3. All isolates were confirmed S. aureus, but only eight were MRSA (cefoxitin resistant, PBP2a positive, mecA positive, growth on all MRSA screening agars). One MRSA isolate was cefoxitin susceptible but PBP2a and mecA positive, and the remaining 33 were cefoxitin susceptible, PBP2a negative, and mecA negative; interestingly, these isolates grew inconsistently across MRSA screening agars and had susceptibility profiles consistent with that of borderline oxacillin-resistant S. aureus (BORSA).
4. Comparative genomic analyses found these BORSA isolates to be phylogenetically diverse and not representative of clonal expansion or shared gene content, though clones of two NICU strains were infrequently observed over 8 months.
5. We identified 6 features-substitutions and truncations in PBP2, PBP4, and GdpP and beta-lactamase hyperproduction-that were used to generate a random forest classifier to distinguish BORSA from methicillin-susceptible S. aureus (MSSA) in our cohort.
6. Our model demonstrated a robust ability to predict the BORSA phenotype among isolates collected across two continents (validation area under the curve [AUC], 0.902). Taking these findings together, we observed an unexpected prevalence of BORSA in our NICU, BORSA misclassification by existing MRSA screening methods, and markers that are together discriminatory for BORSA and MSSA within our cohort. This work has implications for epidemiological reporting of MRSA rates for centers using different screening methods.
7. In this study, we found a high prevalence of Staphylococcus aureus isolates exhibiting a borderline oxacillin resistance phenotype (BORSA) in our neonatal intensive care unit (NICU) serendipitously due to the type of MRSA screening agar used by our laboratory for active surveillance cultures.
8. Subsequent phenotypic and molecular characterization highlighted an unexpected prevalence and variability of BORSA isolates. Through whole-genome sequencing, we interrogated core and accessory genome content and generated a random forest classification model to identify mutations and truncations in the PBP2, PBP4, and GdpP proteins and beta-lactamase hyperproduction, which correlated with BORSA and MSSA phenotypes among S. aureus clinical isolates collected across two continents.
9. In consideration of these findings, this work will help clinical microbiology laboratories and clinicians identify MRSA screening shortfalls and draw attention to the non-mecA-mediated BORSA phenotype.

nvestigation of Candidal Species among People Who Suffer from Oral Potentially Malignant Disorders and Oral Squamous Cell Carcinoma.