A patient develops a severe gastrointestinal illness after consuming undercooked poultry. Stool culture yields a Gram-negative, microaerophilic, curved bacillus that is oxidase-positive. The MOST likely organism is:

Staphylococcus epidermidis, a common cause of healthcare-associated infections, forms biofilms on medical devices. The production of polysaccharide intercellular adhesin (PIA) is a key factor in biofilm maturation.
The expression of PIA is primarily regulated by:

A patient with a history of recurrent Clostridioides difficile infection (CDI) is being considered for fecal microbiota transplantation (FMT). Pre-FMT screening of the donor stool sample should include comprehensive testing to exclude potential transmission of enteric pathogens. Which of the following would be the MOST critical to rule out in the donor stool?

A microbiology laboratory is asked to identify the causative agent of a fungal keratitis. Microscopic examination of corneal scrapings reveals broad, aseptate hyphae with right-angle branching. The MOST likely genus is:

A clinical microbiology laboratory is implementing a new real-time PCR assay for the direct detection of Chlamydia trachomatis in urine samples. To ensure the accuracy of negative results, it is essential to include: