Lab Matters Fall 2024 | Page 60

APHL 2024 POSTER ABSTRACTS

contact signaling . Our findings open new areas of inquiry into the importance of calcium homeostasis to cell physiology and cell-cell interactions in bacterial communities .

Presenter : Tayler Farrington , taylerlfarrington1206 @ gmail . com these data will guide decisions to be made regarding whether or not M . genitalium should be included in routine testing for all NYC DOHMH sexual health clinics and PHL Quickie Labs .

Presenter : Elizabeth Watts , tqf6 @ cdc . gov

Mycoplasma genitalium Diagnosis Prevalence Among Persons Seeking Treatment in New York City Sexual Health Clinics During June 2022 – March 2023

E . Watts 1 , T . Jean-Geffrard 2 , K . Sanchez 2 , J . Tang 2 , P . Pathela 2 , A . Khan 2 , J . Aracena 2 , C . Borges 2 , U . Siemetzki-Kapoor 2 , Centers for Disease Control and Prevention 1 , New York City Department of Health and Mental Hygiene 2

Mycoplasma genitalium , a sexually transmitted bacterium , has an estimated 1 %– 3 % prevalence in the United States and is currently on CDC ’ s watch list for antimicrobial resistance threats . Although mostly asymptomatic , M . genitalium infections have been associated with pelvic inflammatory disease , infertility and preterm birth . It has been commonly found in coinfections with Chlamydia trachomatis or Neisseria gonorrhea . M . genitalium is not as commonly known as chlamydia and gonorrhea , causing it to be frequently overlooked and patients are treated only for the latter . Because of the location of M . genitalium in the cell , treatments used for chlamydia and gonorrhea do not effectively clear M . genitalium and can lead to increased antibiotic resistance of the bacterium . This is concerning , considering asymptomatic nature and prevalence observed among certain populations . The New York City Department of Health and Mental Hygiene ( NYC DOHMH ) is considering use of a routine M . genitalium test but limited local prevalence data is available that would guide medical providers for optimal screening practices . We sought to more fully understand M . genitalium prevalence among specimens collected at NYC DOHMH sexual health clinics to better guide use of routine M . genitalium testing at these clinics and at public health laboratory ( PHL ) Quickie Labs .

Remnant rectal swabs , endocervical swabs , urethral swabs and urine specimens ( from both symptomatic and asymptomatic patients ) that were routinely submitted at NYC DOHMH sexual health clinics for detection of C . trachomatis and N . gonorrhea were tested for M . genitalium using the Hologic ® Aptima ® Mycoplasma genitalium assay on the Hologic ® Panther ® System .

A total of 4,121 specimens during June 2022 – March 2023 were tested using the Hologic ® Aptima ® Mycoplasma genitalium assay . We observed a 12.1 % M . genitalium prevalence ; urethral swabs had the highest percent positivity ( 22 %), 13.0 % with rectal swabs , 10.3 % with endocervical swabs and urine specimens had the lowest percent positivity at 9.8 %.

Although estimated prevalence of M . genitalium in the US is relatively low , prevalence among the population that visits NYC DOHMH sexual health clinics is higher . This higher prevalence amongst those who visit the clinics is most likely due to presence of symptoms and their need to seek care . To better understand these data , future plans include characterizing symptom status at the clinic visit , age , sexual orientation and race and ethnicity and correlation of M . genitalium with other sexually transmitted infections , such as chlamydia and gonorrhea . We anticipate that

Pseudomonas aeruginosa RhlI Variants Exposure to Antibiotics

M . Schumacher 1 , J . Paczkowski 2 , SUNY Albany 1 , New York State Public Health Lab , Wadsworth Center 2

Pseudomonas aeruginosa ( PA ) is a common environmental bacterium that can transition to being an opportunistic pathogen when brought into a healthcare setting . PA is of particular concern to those patients who are on ventilators , have catheters , have burn wounds , or have cystic fibrosis ( CF ). PA is a common pathogen in the CF community , often being acquired in early childhood and persisting throughout adulthood . Due to the high rate of antibiotic resistance in PA , CDC has designated it has a pathogen of serious concern . PA expresses a suite of genes that are responsible for its increased antibiotic resistance such as efflux pumps and biofilm components , most of which are quorum sensing ( QS ) regulated . QS is the mechanism by which bacterial cell-cell communication occurs . Canonically , PA QS is initiated in a hierarchical manner starting with the Las system , then the Rhl system and finally the Pqs system . These QS systems are activated at high cell density via the accumulation of autoinducers ( AI ) specific for each system . For example , the Rhl system is composed of an autoinducer synthase , RhlI , which produces the AI C4 homoserine lactone ( HSL ). When C4HSL reaches an optimal density , it binds to its cognate receptor / transcription factor RhlR which goes on to activate QS regulated genes . However , in both acute and chronic clinical strains of PA , there are commonly observed perturbations to the QS systems , specifically there are frequent lasR inactivating mutations and rhlI SNPs . We have recently described the importance of these rhlI SNPs in a LasR- background : the Las and Rhl systems both use the same pool of precursors to produce AI and in a LasR- background , there is an accumulation of C4HSL which becomes inhibitory . The rhlI SNPs allow for a recalibration of C4HSL concentrations in a LasR- background to a normal level allowing for the progression of QS . Often , these types of mutations come with a benefit-cost trade off and here we explore the possibility of increased antibiotic susceptibility with the introduction of these rhlI SNPs in a LasRbackground . To assess the antibiotic susceptibility profile of these strains , we conducted Kirby-Bauer disk diffusion assays and observed that the RhlI variants conferred increased resistance to some antibiotics while increased susceptibility to others . Interestingly , in the presence of certain antibiotics — kanamycin , ampicillin , vancomycin and aztreonam , the RhlI variant strains developed ‘ ridges ’ around the zone of inhibition which are raised on the plate with increased pyocyanin production . To further investigate this , we conducted RT-qPCR to assess the regulation of common QS genes in these ridges . We found that in the presence of vancomycin , all three variants have roughly a 20-fold increase in mexG expression , part of the MexGHI-OmpD efflux system , when compared to their untreated counterparts . Additionally , in the presence of aztreonam , ampicillin and kanamycin , the RhlI P159S variant showed a 20- , 40- and 55-fold increase in phzB1 ,