Uloga citomegalovirusne infekcije u patogenezi parodontne bolesti

The main characteristic of periodontal disease is chronic inflammation that leads to progressive destruction of the connective tissues and bone with subsequent tooth mobility and finally tooth loss. Traditionally, the pathogenesis of periodontitis was based on the infection caused by bacteria that colonize tooth surface and gingival sulcus. Accumulated evidence show that host response factors such as inflammatory reaction and activation of the innate immune system are critical to the pathogenesis of periodontal disease. Periodontal disease has been widely recognized as a chronic disease but the nature of chronicity remains unclear. The question is whether periodontal disease is a continuous process or consists of episodes of exacerbations and remissions. Maybe cytomegalovirus infection of the periodontium, depending on the latent or active phase of infection, can partly explain the episodic progressive nature of periodontal disease. Cytomegalovirus infection impairs periodontal defense and permits overgrowth of periodontopathogenic bacteria. Owing to advances in new technologies, experimental evidence show the influence and interrelatedness of genomic, epigenetic, proteomic and metabolic factors in the pathogenesis of periodontal disease. Data on the pathogenesis of periodontal disease are reviewed.Glavna značajka parodontne bolesti je kronična upala koja vodi progresivnom razaranju vezivnog tkiva i kosti s posljedičnim klimanjem i na kraju ispadanjem zuba. Tradicionalno, patogeneza parodontitisa se temelji na infekciji uzrokovanoj bakterijama koje koloniziraju površinu zuba i gingivnog sulkusa. Dostupna literatura pokazuje da su činitelji obrane domaćina kao što je upalna reakcija i aktiviranje prirođenog imunog sustava presudno važni u patogenezi parodontne bolesti. Općenito se smatra da je parodontna bolest kronična, iako narav kroniciteta nije u potpunosti jasna. Pitanje je je li parodontna bolest trajan proces ili se sastoji od niza epizoda egzacerbacija i remisija. Moguće je da citomegalovirusna infekcija parodontnog tkiva, ovisno o latentnoj ili aktivnoj fazi infekcije, može djelomice objasniti progresivnu narav parodontne bolesti koja se javlja u epizodama. Citomegalovirusna infekcija smanjuje obranu parodontnog tkiva i tako omogućuje prekomjeran rast parodontopatogenih bakterija. Zahvaljujući napretku u razvoju novih tehnologija eksperimentalni podatci pokazuju utjecaj i međusobnu povezanost genomskih, epigenetskih, proteomskih i metaboličnih čimbenika u patogenezi parodontne bolesti. U ovom se radu daje pregled spoznaja vezanih za parodontnu bolest

DIAGNOSTIC APPROACH AND THERAPY FOR CYTOMEGALOVIRUS (CMV) INFECTION FOLLOWING ALLOGENEIC STEM CELL TRANSPLANTATION

Unatoč napretku u dijagnostici i sprječavanju CMV-bolesti u posljednjih nekoliko desetljeća, CMV-infekcija i dalje je velik dijagnostički i terapijski problem u primatelja alogenih krvotvornih matičnih stanica (aloKMS). Pored znatnog pobola koji se očituje u izravnim učincima CMV-infekcije (hepatitis, gastrointestinalna bolest, pneumonija, retinits), CMV neizravnim djelovanjem povećava osjetljivost prema oportunističkim infekcijama te povećava rizik od odbacivanja presatka i smrtnosti pridružene presadbi. Također, zbog mijelosupresije, nefrotoksičnosti ili pojave CMV-rezistentnih sojeva javljaju se ograničenja u upotrebi antivirusnih tvari koje se rabe za kontrolu CMV-infekcije. Cilj je ovoga rada prikazati probleme vezane uz CMV-infekciju koji se javljaju u primatelja aloKMS s posebnim naglaskom na dijagnostiku i liječenje odnosno sprječavanje nastanka CMV-bolesti.In spite of improvements in diagnostics and prevention of CMV disease in recent decades, CMV infection still remains major concern in terms of diagnosis and therapy in recipients of allogeneic stem cells. Besides considerable morbidity with direct effects of CMV infection (hepatitis, gastrointestinal disease, pneumonia, retinitis), there are also indirect effects such as increased susceptibility to opportunistic infections and an increased risk of graft rejection and transplant-related mortality. Also, myelosuppression, nephrotoxicity and emergence of drug-resistant CMV strains may limit the use of antiviral agents for the control of CMV infection. The aim of this paper is to show the problems associated with CMV infection in recipients of allogeneic stem cells with special emphasis on diagnostic procedures and treatment or prophylaxis of CMV disease

Diagnostic Methods for Evaluation of Microbial Flora in Periodontitis

Iako oralnu floru čini više od 300 bakterijskih vrsta, smatra se da samo nekoliko vrsta, pojedinačnih ili u kombinaciji, inicira progresiju parodontitisa. Parodontnim patogenima smatraju se: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus, Treponema denticola i drugi. Već su više od 20 godina tehnike kulture primarne metode za identifikaciju i proučavanje patogena. Tehnike kulture omogućuju da se otkrije najširi spektar bakterija iz subgingivne flore, odrede bakterijske vrste i antibakterijska osjetljivost. Selektivne kulture uključuju upotrebu medija ograničenih za određene mikroorganizme, a neselektivni mediji osiguravaju maksimalni rast najizraženijih mikroorganizama flore. S obzirom na tehničke poteškoće, kultiviranje mikroorganizmima može biti nepovoljno i vremenski i financijski. Zato su imunotestovi, enzimski i DNA testovi razvijeni kao brze i financijski povoljne alternative tehnikama kulture. Molekularne dijagnostičke tehnike, DNA sonde i lančana reakcija polimeraze, PCR, osobito su korisne za otkrivanje bakterija i virusa koji se ne mogu uzgojiti in vitro ili su neosjetljivi na današnje tehnike kultiviranja. Senzitivnost i specifičnost tih testova pokazala se je optimalnom s obzirom na postojanje brojnih bakterija u uzorcima plaka.Although over 300 bacterial species make up the oral flora, it is thought that only a few, either alone or in combination, initiate the progression of periodontitis. For over 20 years, culture techniques have been the primary method of identifying and studying putative pathogens. Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus and Treponema denticola are considered bacterial pathogens. Culture techniques enable versatility in characterizing the subgingival flora, allow for speciation and antibiotic susceptibility testing. Selective culturing involves the use of media restrictive to certain microorganisms, while nonselective media provides maximal growth and captures a predominant cultivable flora. In addition to technical problems, cultivating microorganisms can be both time consuming and costly. Molecular diagnostic techniques, DNA probes and polymerase chain reaction are especially useful in detecting those bacteria and viruses that cannot be cultivated in vitro or are not sensitive to current cultivating techniques. Sensitivity and specificity is optimal according to the great number of bacteria present in plaque samples

THE ROLE OF IgG AVIDITY IN DIAGNOSTICS OF CYTOMEGALOVIRUS INFECTION DURING PREGNANCY

Cilj istraživanja. Cytomegalovirus (CMV) je jedan od vodećih uzroka mentalne retardacije i drugih neuroloških poremećaja u djece. Do danas ne postoji općenito prihvaćen algoritam za detekciju intrauterinih CMV infekcija tijekom trudnoće i neonatalnog razdoblja. Primarne CMV infekcije tijekom trudnoće predstavljaju 40% rizika od prijenosa virusa s majke na dijete. Želja nam je u ovom kratkom prikazu izdvojiti trudnice u kojih smo pomoću metode određivanja indeksa avidnosti (IA) specifičnih CMV IgG protutijela detektirali primarnu CMV infekciju. Materijal i metode. Ovaj prikaz obuhvaća 33 trudnice u čijim smo uzorcima seruma detektirali specifična CMV IgM i IgG protutijela, te IA IgG protutijela. Sve uzorke krvi testirali smo i testom antigenemije CMV pp65. Rezultati. U ispitivanoj skupini 3 (9%) trud¬nica bilo je seronegativno, a 30 (91%) seropozitivno. Niski IA detektirali smo u 1(3%), srednji u 3 (9%), a visoki u 26 (79%) trudnica. Specifična CMV IgM protutijela i IgG protutijela srednjeg IA detektirali smo u 5 (15%) trudnica. Svi uzorci krvi testirani testom antigenemije CMV pp65 bili su negativni. Zaključak. Pomoću testa određivanja avidnosti IgG protutijela moguće je u trudnica utvrditi i razlikovati primarnu od ponovljene CMV infekcije.. Objective. Cytomegalovirus (CMV) is one of the leading causes of mental retardation and other neurological defects in infants. To date, there is no commonly accepted algorithm for detection of intrauterine HCMV infections during pregnancy and neonatal period. Primary CMV infections during gestation present a 40% risk of intrauterine transmission in contrast to nonprimary infections. In this small study, we decided to identify pregnant women with primary CMV infection with IgG avidity test. Material and methods. The study included 33 pregnant women whose sera were tested to CMV IgM, IgG antibodies and IgG avidity. All the blood samples were tested with antigenemia CMV pp65 test. Results. 3 (9%) pregnant women were CMV seronegative and 30 (91%) were CMV seropositive. Low IgG avidity index (AI) was detected in 1 (3%), intermediate in 3 (9%) and high AI in 26 (79%) pregnant women. CMV IgM antibodies with intermediate IgG AI were detected in 5 (15%) pregnant women. All the blood samples tested with antigenemia CMV pp65 test were negative. Conclusion. IgG avidity test differentiates primary from nonprimary CMV infection in pregnant women

Seroprevalencija na viruse iz herpes grupe u bolesnika na hemodijalizi

Herpes group viruses (herpes simplex virus, HSV; varicella-zoster virus, VZV; cytomegalovirus, CMV; and Epstein-Barr virus, EBV) remain an important cause of morbidity in immunocompromised persons. The aim of the study was to analyze the prevalence of HSV-1, HSV-2, VZV, CMV and EBV in patients undergoing hemodialysis. During a three-year period (2013-2015), 152 consecutive serum samples from hemodialysis patients and 150 healthy subjects (control group) were tested for the presence of IgM/IgG antibodies to herpes group viruses. Serologic tests were performed using a commercial enzyme-linked immunosorbent assay (ELISA) or enzyme-linked immunofluorescent assay (ELFA). Hemodialysis patients showed significantly higher CMV IgG seropositivity compared to controls (88.2% vs. 78.7%, p=0.011). In addition, seroprevalence rates of HSV-1 and VZV were higher in hemodialysis patients; however, these differences did not reach statistical significance (85.5% vs. 80.0%, p=0.054 and 99.3% vs. 96.0%, p=0.051, respectively). The prevalence of HSV-2 and EBV was similar in both groups (12.5% vs. 12.7%, p=0.137 and 98.0% vs. 95.3%, p=0.113, respectively). There was no difference in IgG seropositivity according to gender and place of residence. Logistic regression showed that older age was a significant predictor for CMV and EBV IgG seropositivity (increase in age by one year: CMV OR=1.055; 95%CI=1.030-1.080 and EBV OR=1.075, 95%CI=1.023-1.130).Virusi iz herpes grupe (herpes simpleks virus, HSV; varičela-zoster virus, VZV; citomegalovirus, CMV; Epstein-Barrov virus, EBV) su značajan uzrok smrtnosti u imunokompromitiranih osoba. Cilj rada bio je analizirati učestalost HSV-1, HSV-2, VZV, CMV i EBV u bolesnika koji se liječe hemodijalizom. Tijekom trogodišnjeg razdoblja (2013.-2015.) ispitano je ukupno 152 uzastopno pristiglih uzoraka seruma bolesnika na hemodijalizi te 150 uzoraka seruma zdravih osoba (kontrolna skupina) na prisutnost herpes virusnih IgM/IgG protutijela. Serološko testiranje učinjeno je pomoću komercijalnog dijagnostičkog imunoenzimnog testa (ELISA) ili imunoenzimnog testa s fluorescentnom detekcijom (ELFA). Bolesnici na hemodijalizi bili su značajno češće CMV IgG seropozitivni u odnosu na kontrolnu skupinu (88,2% prema 78,7%, p=0,011). Nadalje, seroprevalencija HSV-1 i VZV također je bila viša u bolesnika na hemodijalizi, no statistička značajnost nije dostignuta (85,5% prema 80,0%, p=0,054; 99,3% prema 96,0%, p=0,051). Učestalost HSV-2 i EBV protutijela nije se razlikovala između skupina (12,5% prema 12,7%, p=0,137, odnosno 98,0% prema 95,3%, p=0,113). IgG seroprevalencija nije se razlikovala u odnosu na spol i mjesto prebivališta. Rezultati logističke regresije pokazali su da je starija životna dob značajan čimbenik rizika za CMV i EBV seropozitivnost (porastom dobi za jednu godinu CMV OR=1,055; 95%CI=1,030-1,080; EBV OR=1,075, 95%CI=1,023-1,130)

In vitro synergy and postantibiotic effect of colistin combinations with meropenem and vancomycin against Enterobacteriaceae with multiple carbapenem resistance mechanisms

Aim: The aim of the study was to determine in vitro synergy and postantibiotic effect of colistin alone and combined with meropenem or vancomycin against Enterobacteriaceae producing multiple carbapenemases; combinations of two metallo-β-lactamases (MBL) or MBL with OXA-48. Colistin-resistant strain positive for OXA-48 was also included in the study. ----- Methods: The antibiotic susceptibility was tested by broth microdilution method. Synergy was tested by chequerboard, time-kill and 2-well method. PAE was determined by viable counting. ----- Results: The chequerboard analysis revealed synergy for colistin combination with meropenem in all isolates with FICI values ranging from 0.12 to 0.24. FICI values for combinations with vancomycin were below 0.5 indicating synergy in two out of four isolates. K. pneumoniae 609815 positive for OXA-48 and colistin resistant showed the most pronounced and consistent synergy effect with meropenem in both chequerboard and time-kill method. Synergy effect in time-kill curves, was observed for K pneumoniae 145846 with two MBLs and colistin resistant K. pneumoniae 609815 positive for OXA-48, with both combinations including meropenem and vancomycin. Colistin alone exhibited short postantibiotic effect (PAE) against all tested isolates. Meropenem markedly prolonged the PAE in two isolates in contrast to vancomycin which did not demonstrate significant effect on the duration of PAE. ----- Conclusions: The synergy effect and the duration of PAE was strain and antibiotic dependent but not related to the resistance gene content

FIRST REPORT OF CARBAPENEMASES IN OSIJEK-BARANJA COUNTY IN IMPORTED ENTEROBACTER CLOACAE ISOLATE IN VITRO SUSCEPTIBLE TO CARBAPENEMS

Karbapenemi su često posljednja terapijska opcija za liječenje infekcija uzrokovanih multirezistentnim gram-negativnim bakterijama. Pojava karbapenemaza u izolatima enterobakterija ograničava terapijske mogućnosti. Izolati enterobakterija rezistentni na karbapenem pojavili su se od 2008. diljem Hrvatske. U Osječko-baranjskoj županiji do 2013. godine nije zapažena pojava izolata rezistentnih na karbapenem iz porodice Enterobacteriaceae. Prvi takav izolat (Enterobacter cloacae) identificiran je u kolovozu 2013. godine u bolesnice koja je prethodno boravila u KBC-u Zagreb radi liječenja akutne limfocitne leukemije. Molekularnim metodama dokazana je produkcija VIM-1 metalo-b-laktamaze (MBL). Unatoč produkciji metalo-b-laktamaze izolat nije pokazivao rezistenciju na imipenem i meropenem u disk-difuzijskom i dilucijskom testu. Iz ovog prikaza proizlazi da rutinsko testiranje osjetljivosti koje se provodi u većini mikrobioloških laboratorija ne mora uvijek detektirati karbapenemazu u enterobakterija. Budući da su metalo-b-laktamaze kodirane prenosivim genskim elementima, postoji opasnost od horizontalnog širenja na druge bakterijske izolate enterobakterija i mogućnost pojave bolničkih epidemija.Carbapenems are often the only therapeutic option to treat infections caused by multidrug-resistant Gram-negative bacteria. Emergence of carbapenemases in the isolates of Enterobacteriaceae limits therapeutic options. Carbapenem-resistant Enterobacteriaceae have emerged since 2008 throughout Croatia. In Osijek-Baranja County carbapenem-resistant strains of Enterobacteriaceae were not reported until 2013. The first carbapenem-resistant strain (Enterobacter cloacae) was identified in August 2013 in a patient previously hospitalized at University Hospital Center Zagreb for the treatment of acute lymphoblastic leukemia. Molecular analysis revealed the production of VIM-1 metallo-b-lactamase (MBL). In spite of the metallo-b-lactamase production the strain was not resistant to imipenem and meropenem in disk-diffusion and microdilution test. This report shows that routine susceptibility testing carried out in most laboratories does not necessarily detect carbapenemase production in Enterobacteriaceae. Since these enzymes are encoded on mobile genetic elements there is a risk of horizontal spread to other enterobacterial isolates and the development of hospital outbreaks