Date of Award
Master of Science (MS)
Dr. Peter Chung
Dr. Mandy Peak
Dr. Anu Ghosh
Dr. Barbara McClaskey
The looming threat of increased antibiotic resistance leading to a post-antibiotic world is progressively becoming a reality. A significant portion of the fight against antibiotic resistance development is slowing down the prescribing of antibiotics for unnecessary conditions while simultaneously encouraging stricter adherence to antibiotic course completion. One of the often-unnecessary conditions is acne vulgaris. Though the disease may be unsightly and discouraging, it does little to affect overall health of the individual with the exception of psychosocial affects. Utilizing facial swabs from 144 participants, samples were tested for the colonization of Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis as well as the presence of resistance genes Cerm(X) and Tet(M) using polymerase chain reaction and gel electrophoresis. Amplification of the samples portrayed that Propionibacterium acnes was the most prevalent microbe present, even from samples obtained from students with minimal blemishes. The second most common was Staphyloccocus epidermidis and few samples tested positive for Staphylococcus aureus. Amplification of resistance genes demonstrated fair amounts of resistance present, even in participants who had not taken antibiotics in the last two years. Out of the 144 initial samples, 60 isolated samples were utilized for susceptibility testing and the first set determined a slight decrease in diameter of the resulting zone of inhibition when exposed to clindamycin, doxycycline and tetracycline, but not rifampin.
A subsequent 42 samples were collected for susceptibility testing using direct colony suspension. Results from testing demonstrated a significant decrease in the zones of inhibition between those who had not taken antibiotics and those who had taken two types of antibiotics for general illnesses and acne. The differences between tetracycline, clindamycin, rifampin and doxycycline were 4.64, 6.34, 11.86 and 7.66-millimeters, respectively with significant p-values between rifampin and doxycycline suggesting that the development of resistance is more prevalent in rifampin than previously determined.
Stricklan, Kayla R., "FACIAL MICROBIOTA AND ANTIBIOTIC RESISTANCE: A COMPARATIVE STUDY OBSERVING THE PRESENCE OF RESISTANCE GENES AND DIMINISHED SUSCEPTIBILITY" (2016). Electronic Thesis Collection. 221.