MIC and Agglutination Testing Feb 8th 2024 Purpose Continuing with diagnoses and developing an understanding of our pathogen we took samples from pure cultures of each environment and conducted MIC and Agglutination testing Methods Sample s tested Environment 1 Unit 1 Doorknob Protocols MIC Testing o I first started with the MIC testing by grabbing the materials needed like a sterile solution swabs and a Mueller Hinton plate To test anti microbial resistance it was necessary to plate a pure culture of our sample Using the sterile swab grab an isolated colony and swirl to the desired turbidity McFarland turbidity standard is what we used for concentration Swabbed the Mueller Hinton plate completely rotated 30 degrees and swabbed it again This way the plate is completely covered o Using the Bunson burner sterilize forceps repeated each time grab the antibiotic strip and place from the center to the outer edge of the plate Grown for about 24 48 hours o On 2 8 2024 the MIC levels were analyzed Agglutination Assay o Placed a single drop of the antibodies for S aureus on the circle for Test Latex Reagent Then we used the same samples Unit 1 Doorknob and grabbed an isolated colony with the toothpick We swirled the colony in the solution and waited for agglutination It worked because the antigens and antibodies clumped up together showing a positive result of S aureus on Unit 1 Doorknob Results Observations from Latex Agglutination Test Notes of observations The presence of clumping shows my sample Unit 1 Doorknob was positive for S aureus I ll also note that lack of clumping doesn t mean the other samples are safe they re just not positive for S aureus Observations from Antibiotic Susceptibility Assay Notes of MIC determination The strongest susceptibility was Oxacillin Then vancomycin and lastly Azithromycin Conclusion Discussion Do you have a definitive diagnosis of your organism from the latex agglutination test If so what organism do you have If not what possible organism could you have based on previous thoughts I do I m feeling confident I m working with S aureus on the doorknob I tested Based on MIC data is your organism susceptible or resistant to the different antibiotics tested Which would be best for treatment of this organism if it is causing infection Although susceptible to all the antibiotics It s clear that oxacillin would be the best route of treatment if this sample was for a patient Next Steps What do you think the next steps in your outbreak investigation should be I want to compare my sample of the doorknob to patient samples Especially the MIC levels because a treatment plan should be the next step and making sure one antibiotic can work between samples might be good I d also like to sterilize the NICU again As well as implement more training on hand washing as my sample is from a doorknob