Mycoplasma genitalium kao podcijenjen ili precijenjen uzročnik spolno prenosivih infekcija

master's thesis

• Title (english): Mycoplasma genitalium as underestimated or overestimated cause of sexually transmitted infections
• Author: Tian Košar
• Mentor: Sunčanica Ljubin Sternak (mentor)
• Committee member: Jasmina Vraneš (predsjednik povjerenstva)
• Committee member: Goran Tešović (član povjerenstva)
• Committee member: Sunčanica Ljubin Sternak (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; (Department of Medical Microbiology and Parasitology); Zagreb
• Defense date and country: 2023-07-13, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Medical Microbiology

Abstract

Rod Mycoplasma čini veliki broj vrsta koje kao komenzali ili patogeni žive na sluznicama ljudi i životinja. Ova se skupina bakterija razlikuje od ostalih prokariota po odsutnosti stanične stijenke zbog čega su svi pripadnici intrinzično rezistentni na antibiotike koji blokiraju sintezu peptidoglikana. Klinički najvažniji predstavnici jesu Mycoplasma pneumoniae, Mycoplasma genitalium te Mycoplasma hominis.

M. genitalium emergentni je patogen i danas poznati uzročnik spolno prenosivih infekcija. Zbog reduciranoga genoma i značajnih restrikcija u metabolizmu, ova se bakterija izrazito teško kultivira te izravno ovisi o domaćinu kako bi preživjela. Ona posjeduje nekoliko čimbenika virulencije koji joj omogućuju prilagodbu na parazitski način života, od kojih je najvažnija terminalna struktura s adhezinima.

Kao uzročnik spolno prenosivih infekcija, M. genitalium prenosi se izravnim kontaktom među zaraženim sluznicama. Povećanu učestalost zaraze nalazimo u određenim rizičnim skupinama, dok je prevalencija u općoj populaciji niska. Najčešći sindromi koje ova mikoplazma uzrokuje jesu negonokokni uretritis, cervicitis te upalna zdjelična bolest, a perzistentna infekcija može dovesti i do neplodnosti u oba spola. Sve do razvoja molekularnih metoda, dijagnostika ove bakterije bila je gotovo nemoguća.

Sindromsko liječenje navedenih infekcija jednokratnom dozom azitromicina potaknulo je selekciju sojeva rezistentnih na makrolid s njihovim ubrzanim širenjem, posebice među visoko rizičnim populacijama. Stoga dolazi do povećane upotrebe moksifloksacina. Međutim, ubrzo je prepoznat i gen za rezistenciju na fluorokinolone, a sve se češće bilježi i kombinirana rezistencija na oba antibiotika. Zbog toga se javlja potreba za revizijom postojećih terapijskih opcija, kao i redovit nadzor nad rezistentnim sojevima u populaciji. U konačnici, ova bakterija trebala bi se uvrstiti u dijagnostički protokol za obradu najčešćih infekcija, uz uvođenje obaveznog kontrolnog testa za procjenu uspješnosti po završetku liječenja, kako bi suzbili daljnje širenje rezistencije.

Abstract (english)

The genus Mycoplasma comprises various species that live as commensals or pathogens on the mucous membranes of humans and animals. Unlike other prokaryotes, these bacteria lack the cell wall, making them intrinsically resistant to antibiotics that inhibit peptidoglycan synthesis. Clinically significant representatives include Mycoplasma pneumoniae, Mycoplasma genitalium, and Mycoplasma hominis.

M. genitalium is an emerging pathogen and a known cause of sexually transmitted infections. Due to its reduced genome and significant metabolic restrictions, it directly depends on the host for its survival, but cultivating this bacterium is extremely challenging. Several virulence factors enable it to adapt to a parasitic way of life, with the terminal organelle being the most important among them.

As a sexually transmitted infection, M. genitalium spreads through direct contact between the infected mucous membranes. Increased infection rates are found in certain high-risk groups, while the prevalence in the general population is low. The most common syndromes caused by this mycoplasma are non-gonococcal urethritis, cervicitis, and pelvic inflammatory disease, whereas persistent infection can lead to infertility in both sexes. Molecular diagnostic methods revolutionized the detection of this bacterium, which was previously exceedingly challenging.

A single dose of azithromycin used as a syndromic treatment has led to the selection and rapid spread of macrolide-resistant strains, particularly among the high-risk populations, consequently increasing the use of moxifloxacin. However, the emergence of fluoroquinolone resistance genes has been recognised, and combined resistance to both antibiotics is being reported as well. Therefore, existing therapeutic options should be reevaluated and regular surveillance of resistant strains in the population should be implemented. Ultimately, this bacterium should be included in the diagnostic protocol for the management of common infections, along with the introduction of mandatory test of cure to assess treatment success to curb further spread of resistance.

• Keywords: antimikrobna rezistencija; Mycoplasma genitalium; spolno prenosive infekcije
• Keywords (english): antimicrobial resistance; Mycoplasma genitalium; sexually transmitted infections
• Language: croatian
• URN:NBN: urn:nbn:hr:105:650965
• Study programme: Title: Medicine; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: doktor/doktorica medicine (doktor/doktorica medicine)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-10-25 11:46:08