Microbiological diagnostics of invasive meningococcal disease in Croatia – are standard methods optimal methods even today

Potvrda dijagnoze invazivne meningokokne bolesti (IMB) često je onemogućena zbog rane primjene antibotika. Nekultivacijske molekularne metode postaju zato novi "zlatni standard" u mikrobiološkoj dijagnostici IMB u razvijenim zemljama i preporučeno pomagalo u ostalim zemljama. Uvođenje molekularnih testova 2005. godine u rutinsku dijagnostku IMB u Klinici za infektivne bolesti "Dr. Fran Mihaljević" značajno su ubrzali i unaprijedili postavljanje etiološke dijagnoze. U razdoblju od siječnja 2005. do travnja 2013 godine više od 50% slučajeva IMB potvrđeno je samo real time PCR testom. Pojava invazivnih penicilin-rezistentnih izolata N. meningitidis nameće potrebu praćenja gena penA, odgovornog za rezistenciju na penicilin. Dobra osjetljivost izolata na ciprofloksacin, rifampicin i ceftriakson omogućava nam primjenu ovih antibiotika u profilaksi prema sadašnjim preporukama struke. Serotipizacija i serosubtipizacija nisu više preporučene rutinske metode u karakterizaciji izolata meningokoka. Cjepiva protiv meningokoka grupe B pripremljena od proteina vanjske membrane (OMV cjepiva) mogla su biti primijenjena uspješno uglavnom samo u nacionalnim okvirima. Međutim s razvojem reverzne vakcinologije i pojavom multikomponentnih MenB cjepiva (fHBP, NHBA, NadA, OMP Novi Zeland – P1.7-2,4) postaje značajno genotipizirati lokalne izolate i pratiti obuhvat zaštićenosti populacije ponuđenim novim cjepivima u nacionalnim okvirima. To će zasigurno biti dio našeg budućeg rada samostalno i/ili u suradnji s europskim referentnim centrima za meningokoke i Europskim centrom za prevenciju i kontrolu bolesti (ECDC).Culture-confirmed diagnosis of invasive meningococcal disease (IMD) is often hindered by early antibiotic treatment. Nonculture molecular standardized methods are now essential tools and almost "new gold standard" in microbiological diagnostics of IMD in developed world and recommended tool in other parts of the world. The introduction of the real time PCR in routine diagnostics of IMD at the University Hospital for Infectious Diseases (UHID) in 2005 significantly improved etiological diagnosis of disease. More than 50% of IMD cases of hospitalized patients in UHID from January 2005 to April 2013 were confirmed only by real time PCR. The emergence of penicillin resistant N. meningitidis invasive isolates leads us to the introduction of the detection of penA gene responsible for penicillin resistance. Nevertheless, IMD prophylaxis in Croatia may continue to be based on the current recommendations of epidemiological service due to proved susceptibility to all antibiotics commonly used for this purpose, rifampicin, ciprofloxacin and ceftriaxone. Serotyping and serosubtyping are not any more recommended in routine characterization of meningococcal isolates. OMV vaccines against N. meningitidis serogroup B, prepared from outer membrane proteins, have not proved to be successful supranational. However, after the development of reverse vaccinology and multicomponent MenB (fHBP, NHBA, NadA, OMP New Zealand – P1.7-2,4) vaccine genotyping was placed as an important tool for following up characteristics of invasive meningococcal isolates as well as following up of vaccine coverage with the available new and future MenB vaccines or perhaps broad range vaccines. This will undoubtedly be a part of our future work on the national level and/or in cooperation with other European national reference centres and the European Centre for Disease Prevention and Control (ECDC)

Epidemiological and clinical characteristics of patients with invasive meningococcal disease hospitalized at the University Hospital for Infectious Diseases "Dr. Fran Mihaljevic", Zagreb

Restrospektivno su analizirane epidemiološke i kliničke značajke invazivne meningokokne bolesti (IMB) kod 108 hospitaliziranih bolesnika, u petogodišnjem razdoblju, od 2003. – 2007. godine, što je prosječno iznosilo 22 bolesnika godišnje. IMB je najčešća kod dojenčadi i male djece, te u djece školske dobi. Sveukupno 73% bolesnika bila su djeca u dobi do 15 godina, prosječne starosti 2,8 godina, a 27% su bili stariji bolesnici. Ukupna smrtnost među našim bolesnicima bila je 4,6% (3,7% među djecom do 15 godina, a u starijih bolesnika 6,8%). Bolest se klinički prezentirala kao meningitis kod 14 (13%), sepsa kod 28 (26%) ili sepsa s meningitisom kod 66 (61%) bolesnika. Etiološka dijagnoza bila je potvrđena kod svih bolesnika dokazom uzročnika iz primarno sterilnih materijala (krv i/ili cerebrospinalni likvor). Kultivacijom je uzročnik dokazan u 32%, a molekularnim metodama (PCR) u 74% bolesnika. Prevladavala je N. meningitidis serogrupe B (83%), zatim serogrupe C (12%) te serogrupa W 135 (1,8%), dok je kod 2,7% dokazan negrupabilan soj. Svi hospitalizirani bolesnici bili su sporadični slučajevi, nije zabilježena niti jedna epidemija. U razdoblju od 2003. do 2007. godine kod naših je bolesnika dokazano 7 izolata N. meningitidis smanjene osjetljivosti na penicilin. U svim se slučajevima radilo o izolatima serogrupe B. Uz već postojeća cjepiva protiv meningokoka (A, C, Y, W135), u tijeku su opsežna istraživanja u razvoju i primjeni djelotvornog cjepiva protiv N. meningitidis serogrupe B, koje će, nadamo se, doprinijeti smanjenju incidencije ove teške i potencijalno smrtonosne bolesti.We retrospectively analyzed epidemiological and clinical characteristics of invasive meningococcal disease (IMD) in 108 hospitalized patients in the period of five years, from 2003 to 2007. On average, 22 patients with meningococcal disease were treated per year. IMD was the commonest in infants and small children, and in school age children. Altogether 73 % of all patients were children up to 15 years of age (mean age 2,8 years) while the remaining 27% were older patients. The total mortality rate among our patients was 4,6% (3,7% among children up to 15 years of age, and 6,8% in older patients). The disease clinically presented as meningitis in 14 (13%), as sepsis in 28 (26%) or sepsis with meningitis in 66 (61%) patients. Etiological diagnosis from primarily negative samples (blood and/or cerebrospinal fluid) proved positive in all patients. N.meningitidis was confirmed by cultivation in 32%, and by PCR method in 74% of cases. In etiologically confirmed cases, the most common serogroup of N.meningitidis was serogroup B (83%), followed by serogroup C (12%) and serogroup W135 (1,8%), while in 2,7% of patients a non-groupable strain was isolated. All patients were sporadic cases. In the period from 2003 to 2007, N.meningitidis with reduced susceptibility to penicillin was detected in 7 isolates, all of them belonging to serogroup B. Along with currently available vaccine against meningococcus (A, C, Y, W 135), continuous efforts are undertaken worldwide to develop an efficient vaccine against N. meningitidis serogroup B, that would, we hope, contribute in reducing the incidence of this severe and potentially fatal disease

Microbiological diagnostics of invasive meningococcal disease in Croatia – are standard methods optimal methods even today

Potvrda dijagnoze invazivne meningokokne bolesti (IMB) često je onemogućena zbog rane primjene antibotika. Nekultivacijske molekularne metode postaju zato novi "zlatni standard" u mikrobiološkoj dijagnostici IMB u razvijenim zemljama i preporučeno pomagalo u ostalim zemljama. Uvođenje molekularnih testova 2005. godine u rutinsku dijagnostku IMB u Klinici za infektivne bolesti "Dr. Fran Mihaljević" značajno su ubrzali i unaprijedili postavljanje etiološke dijagnoze. U razdoblju od siječnja 2005. do travnja 2013 godine više od 50% slučajeva IMB potvrđeno je samo real time PCR testom. Pojava invazivnih penicilin-rezistentnih izolata N. meningitidis nameće potrebu praćenja gena penA, odgovornog za rezistenciju na penicilin. Dobra osjetljivost izolata na ciprofloksacin, rifampicin i ceftriakson omogućava nam primjenu ovih antibiotika u profilaksi prema sadašnjim preporukama struke. Serotipizacija i serosubtipizacija nisu više preporučene rutinske metode u karakterizaciji izolata meningokoka. Cjepiva protiv meningokoka grupe B pripremljena od proteina vanjske membrane (OMV cjepiva) mogla su biti primijenjena uspješno uglavnom samo u nacionalnim okvirima. Međutim s razvojem reverzne vakcinologije i pojavom multikomponentnih MenB cjepiva (fHBP, NHBA, NadA, OMP Novi Zeland – P1.7-2,4) postaje značajno genotipizirati lokalne izolate i pratiti obuhvat zaštićenosti populacije ponuđenim novim cjepivima u nacionalnim okvirima. To će zasigurno biti dio našeg budućeg rada samostalno i/ili u suradnji s europskim referentnim centrima za meningokoke i Europskim centrom za prevenciju i kontrolu bolesti (ECDC).Culture-confirmed diagnosis of invasive meningococcal disease (IMD) is often hindered by early antibiotic treatment. Nonculture molecular standardized methods are now essential tools and almost "new gold standard" in microbiological diagnostics of IMD in developed world and recommended tool in other parts of the world. The introduction of the real time PCR in routine diagnostics of IMD at the University Hospital for Infectious Diseases (UHID) in 2005 significantly improved etiological diagnosis of disease. More than 50% of IMD cases of hospitalized patients in UHID from January 2005 to April 2013 were confirmed only by real time PCR. The emergence of penicillin resistant N. meningitidis invasive isolates leads us to the introduction of the detection of penA gene responsible for penicillin resistance. Nevertheless, IMD prophylaxis in Croatia may continue to be based on the current recommendations of epidemiological service due to proved susceptibility to all antibiotics commonly used for this purpose, rifampicin, ciprofloxacin and ceftriaxone. Serotyping and serosubtyping are not any more recommended in routine characterization of meningococcal isolates. OMV vaccines against N. meningitidis serogroup B, prepared from outer membrane proteins, have not proved to be successful supranational. However, after the development of reverse vaccinology and multicomponent MenB (fHBP, NHBA, NadA, OMP New Zealand – P1.7-2,4) vaccine genotyping was placed as an important tool for following up characteristics of invasive meningococcal isolates as well as following up of vaccine coverage with the available new and future MenB vaccines or perhaps broad range vaccines. This will undoubtedly be a part of our future work on the national level and/or in cooperation with other European national reference centres and the European Centre for Disease Prevention and Control (ECDC)

The rise and fall of resistant bacteria

Problem rezistencije bakterija na antibiotike jedan je od vodećih problema današnje medicine. Hrvatska sistematski prati stope rezistencije u najčešćih patogena od 1996. g. te je u ovom radu analizirano kretanje stopa rezistencije u Hrvatskoj u razdoblju od 2000. do 2014. g. Trideset pet hrvatskih mikrobioloških laboratorija (pokrivenost populacije >90 %) slalo je podatke o osjetljivosti kliničkih izolata (ponavljani izolati su isključivani) u Referentni centar Ministarstva zdravlja za praćenje rezistencije gdje su podaci agregirani i analizirani. Otpornost streptokoka grupe A na makrolide pokazuje lagani trend pada. Smanjena osjetljivost pneumokoka na penicilin pokazuje manje oscilacije bez izraženog trenda. Rezistencija na vankomicin je prisutna u E. faecium s trendom porasta u zadnje dvije godine. Rezistencija na cefalosporine 3. generacije i kinolone je u E. coli u blagom, ali stalnom porastu, a u K. pneumoniae je znatno viša, ali ne pokazuje porast zadnjih godina. Rezistencija na karbapeneme je u P. aeruginosa u blagom porastu, a u A. baumannii je naglo porasla od 2008. g. Hrvatska ima dobro organiziranu mrežu za praćenje rezistencije i poznavanje stopa rezistencije je važan prvi korak u kontroli širenja rezistencije. U kontroli širenja rezistencije također je bitno jačati ulogu timova za kontrolu bolničkih infekcija te prepustiti antimikrobnu terapiju timovima za rukovođenje antimikrobnom terapijom.Antimicrobial resistance (AMR) is one of the leading problems in modern medicine. Antibiotic resistance surveillance in Croatia was set up in 1996 and antibiotic resistance rates in most frequent bacterial pathogens were analysed for the period 2000 till 2014. Thirty five Croatian microbiology laboratories (population coverage >90 %) have sent antibiotic sensitivity data for clinical isolates (copy isolates were excluded) to the Ministry of Health Reference Center for Antibiotic Resistance Surveillance where these data were aggregated and analysed. Macrolide resistance in group Astreptococci shows a mild decreasing trend. Penicillin non-susceptibility in pneumococci demonstrates slight oscillations without any trend. Vancomycin resistance was recorded in Enterococcus faecium with increasing trend in the last two years. Resistance to 3rd generation cephalosporins and quinolones is slightly but constantly increasing in E. coli and in K. pneumoniae, although significantly higher, it does not demonstrate increase in the last few years. Carbapenem resistance is slightly increasing in P. aeruginosa and has abruptly increased in A. baumannii since 2008. Croatia has a well organized antibiotic resistance surveillance network and knowing local resistance rates is an important first step in controlling antibiotic resistance. For successful AMR control it is also very important to strengthen the role of infection control teams and to establish antibiotic stewardship teams

Escherichia coli – from commensal organism to multiply resistant uropathogen

Escherichia coli sastavni je dio crijevne mikrobiote, no ujedno i najčešći uzročnik infekcija mokraćnog sustava. Brojni čimbenici virulencije mogu različito biti izraženi u različitim sojevima. Opisano je nekoliko uspješnih klonova ekstraintestinalne patogene E. coli (exPEC) koji su se raširili u mnogim krajevima svijeta. Ovi klonovi su zastupljeniji među uzročnicima cistitisa i pijelonefritisa negoli među izolatima iz stolice zdravih osoba, a češće nego sporadični klonovi pokazuju rezistenciju na jedan ili više antibiotika. Trimetoprim-sulfametoksazol je dugo vremena bio prvi lijek izbora u liječenju mnogih kategorija uroinfekcija. Zbog visoke rezistencije koja je bila očita već 1990-tih godina ovaj se antibiotik u mnogim dijelovima svijeta, pa i u Hrvatskoj više ne preporuča u empirijskoj terapiji infekcija mokraćnog sustava. Rezistencija na trimetoprim-sulfametoksazol je u Hrvatskoj iznad 20% i nije se bitno mijenjala posljednjih deset godina. Nasuprot tome, rezistencija na kinolone i beta-laktamske antibiotike u desetgodišnjem razdoblju pokazuje trend porasta. Hrvatska je 2011. g. prešla s američkih na europske standarde pri čemu je došlo do manjih pomaka u stopama rezistencije zbog administrativnog mijenjanja graničnih koncentracija za neke antibiotike. E. coli može akvirirati raznolike mehanizme rezistencije na svaki od antibiotika, pri čemu su, zbog lakše izmjene gena, izuzetno važni geni za rezistenciju koji se nalaze na plazmidima.Escherichia coli is an integral part of gut microbiota but at the same time it is the most frequent causative agent of urinary tract infections (UTI). Numerous virulence factors are variably expressed in different strains. Several successful clones of extraintestinal pathogenic E. coli (exPEC) have spread worldwide. These clones are more prevalent among causative agents of cystitis and pyelonephritis than among fecal isolates in healthy humans and they express resistance to one or more antibiotics more often than sporadic clones. Trimethoprime- sulfamethoxazole was the first line antibiotic for the treatment of several UTI categories for a long time. Due to high rates of resistance that became apparent in the 1990s this antibiotic is no more recommended in empirical therapy of UTI in many parts of the world, including Croatia. Resistance to trimethoprime-sulfamethoxazole is over 20 % in Croatia and this did not change over the last ten years. In contrast, resistance to quinolones and beta-lactams shows increasing trend over the past ten year period. In 2011 Croatia switched from American to European sensitivity testing standards which slightly influenced resistance rates. E. coli can acquire various resistance mechanisms to a variety of antibiotics. Plasmid mediated resistance mechanisms are especially important because of the ease of horizontal gene exchange

Clinical Manifestations of Bartonella henselae Infection Among Children: A Single Centre Study

Cilj: Cilj istraživanja je prikazati epidemiološke, kliničke i laboratorijske karakteristike B. henselae infekcije u djece liječene u Klinici za infektivne bolesti „Dr. Fran Mihaljević“ u Zagrebu, u razdoblju od siječnja 2014. do lipnja 2019. godine. Materijali i metode: Retrospektivno smo istražili kliničke karakteristike, epidemiologiju i laboratorijske parametre u bolesnika mlađih od 18 godina kod kojih je infekcija potvrđena indirektnim imunoflorescentnim testom za IgM i IgG na B. henselae ili detekcijom B. henselae lančanom reakcijom polimerazom iz punktata limfnog čvora. Rezultati: Od ukupno 104 bolesnika, 47 (45,1%) je bilo ženskog i 57 (54,8%) muškog spola. Medijan dobi iznosio je 9,7 godina (raspon, 1,1 do 17,3 godina). Kontakt s mačkom zabilježen je u 101 bolesnika (97,1%). Infekcija je potvrđena serološki u 87 (83,6%), PCR metodom u 5 (4,8%), a kombinacijom obje metode u 12 (11,5%) bolesnika. Najčešća manifestacija infekcije bila je regionalna limfadenopatija, a slijede diseminirani oblik bolesti, encefalopatija i vrućica nepoznatog porijekla. U 12/92 (13%) bolesnika s limfadenopatijom došlo je do razvoja supurativne upale koja je potvrđena citološki. U 100 (96,1%) bolesnika došlo je do izlječenja. Zaključak: Infekcija B. henselae u djece najčešće je blaga bolest koja se manifestira regionalnom limfadenopatijom. Serologija i lančana reakcija polimerazom metode su izbora za dijagnozu bolesti. Duljina liječenja i izbor terapije ovise o kliničkoj manifestaciji infekcije uz vrlo visoku stopu izlječenja.Objectives: The aim of this study was to analyze clinical manifestations, epidemiology and laboratory parameters of B. henselae infection among children treated at the University Hospital for Infectious Diseases “Dr. Fran Mihaljević”, Zagreb from January 2014 until June 2019. Materials and methods: We retrospectively analyzed the epidemiology, clinical and laboratory characteristics among children with positive indirect immunofluorescence assay for B. henselae IgM and IgG or positive B. henselae polymerase chain reaction from lymph node aspirate. Results: A total of 104 patients, 47 (45,1%) female and 57 (54,8%) male were enrolled. The median age was 9,7 (range, 1,1 to 17,3 years). A history of cat contact was present in 101 (97,1%) children. Acute infection was serologically confirmed in 87 (83,6%), in 5 (4,8%) with PCR while both methods were positive in 12 (11,5%) patients. The presentation on B. henselae infection were regional lymphadenopathy, disseminated disease, encephalopathy and fever of unknown origin. Suppurative inflammation was the most common complication in patients with lymphadenopathy 12/92 (13%). Full recovery was the most frequent outcome (96,1%). Conclusion: B. henselae infection among children is usually a mild disease presented as regional lymphadenopathy. Serology and polymerase chain reaction are useful tests for diagnosis. Treatment duration and choice of therapy depend on clinical manifestation and developed complications

A REPORT OF RARELY OBSERVED RESISTANCE PATTERN TO CARBAPENEMS IN A CLINICAL ISOLATE OF ENTEROBACTER CLOACAE

Rad izvještava o pojavi soja Enterobacter cloacae u kojeg je dokazan rijetko viđen oblik otpornosti na karbapeneme posredovan enzimom IMI-1, skupine A beta-laktamaza. Soj je izoliran iz obriska rane u bolesnika koji je zbog infekcije kirurške rane prethodno liječen meropenemom. Ograničen izbor antibiotika kojima se mogu liječiti infekcije uzrokovane ovakvim uzročnicima upućuje na nužnost točne identifikacije višestruko otpornih gram-negativnih mikroorganizama i otkrivanje njihovih mehanizama otpornosti. Prepoznavanje višestruko otpornih mikroorganizama naglašava važnost kontinuiranoga mikrobiološkog nadzora bolesnika, osobito u jedinicama intenzivnog liječenja. U prikazanoj ustanovi nije bilo sekundarnog širenja ovog soja. Identifikacija novih mehanizama otpornosti pomaže kliničarima u izboru ciljane terapije, a istodobno je nužna za uspješno sprječavanje širenja infekcija izazvanih višestruko otpornim mikroorganizmima.The paper reports on the emergence of strain in which Enterobacter cloacae has demonstrated an unusual form of resistance to carbapenems mediated by enzyme IMI-1, class A beta-lactamase. The strain was isolated from a wound swab in the patient who had a surgical wound infection previously treated with meropenem. Limited choice of antibiotics that can treat infections caused by these pathogens indicates the necessity of accurate identification of multiple resistant gram-negative microorganisms and mechanisms of their resistance. Recognition of multiresistant gram-negative microorganisms emphasizes the importance of continuous microbiological monitoring of patients, especially in intensive care units. In the investigated institution there was no secondary spread of this strain. Identifying new mechanisms of resistance will be helpful to clinicians in selection of targeted therapy, while important for efficient prevention of spreading infections caused by multiple resistant microorganisms

Epidemic spread of OXA-48 beta-lactamase in Croatia

PURPOSE: A dramatic increase in OXA-48 β-lactamase was observed recently not only in large hospital centres, but also in smaller suburban hospital centres in geographic areas bordering Croatia. The aim of the study was to analyse the epidemiology, the mechanisms of antibiotic resistance and the routes of spread of OXA-48 carbapenemase in Croatia. ----- METHODS: Carbapenemase and other β-lactamase and fluoroquinolone resistance genes were detected by PCR and sequencing. Whole-genome sequencing (WGS) was performed on five representative isolates. The isolates were genotyped by PFGE. ----- RESULTS: Forty-eight isolates positive for OXA-48, collected from seven hospital centres in Croatia from May 2016 to May 2017, were analysed (40 Klebsiella pneumoniae, 5 Enterobacter cloacae, 2 Escherichia coli and one Citrobacter freundii). Thirty-three isolates were ESBL positive and harboured group 1 CTX-M 1 β-lactamases. In addition to the β-lactam resistance genes detected by PCR (blaSHV-1, blaOXA-48 and blaOXA-1), WGS of five representative isolates revealed the presence of genes encoding aminoglycoside resistance, aadA2 and aph3-Ia, fluoroquinolone resistance determinants aac(6)Ib-c, oqxA and oqxB, the sulfonamide resistance gene sul1, and fosA (fosfomycin resistance). IncL plasmid was found in all isolates. Two K. pneumoniae isolates belonged to ST16, two E. cloacae to ST66 and E. coli to ST354. K. pneumoniae isolates were allocated to five clusters by PFGE which occured in different hospitals, indicating epidemic spread. ----- CONCLUSIONS: The OXA-48-positive organisms found in this study showed wide variability in antibiotic susceptibility, β-lactamase content and PFGE banding patterns. This study revealed a switch from the predominance of VIM-1 in 2012-2013 to that of OXA-48 in the 2015 to 2017

Resistant enterobacteria in Croatia – the role of national antibiotic resistance surveillance

Rezistencija enterobakterija na antibiotike već dugo ugrožava uspjeh empirijske antimikrobne terapije, no posebno zabrinjava pojava izolata rezistentnih na sve raspoložive antibiotike. U Hrvatskoj se rezistencija na antibiotike sustavno prati kroz rad Odbora za praćenje rezistencije Akademije medicinskih znanosti Hrvatske i Referentnog centra Ministarstva zdravlja za praćenje rezistencije (RC) pri Klinici za infektivne bolesti "Dr. Fran Mihaljević" i dio je nacionalnog programa kojeg provodi Interdisciplinarna sekcija za kontrolu rezistencije na antibiotike (ISKRA). U sklopu nacionalnog praćenja RC prikuplja izolate enterobakterija rijetkog fenotipa iz cijele Hrvatske, što je omogućilo uočavanje prvih sojeva s novim mehanizmima rezistencije: prvi izolati s plazmidnim AmpC β-laktamazama opisani su 2003. g., s NDM enzimom 2009. g., a izolati s KPC β-laktamazama 2011. g. Niti jedan od ovih enzima se još nije značajno proširio Hrvatskom. Pravodobno otkrivanje sojeva s novim mehanizmom rezistencije, pogotovo onih koji pokazuju i veliki epidemijski potencijal, poput ST 258 Klebsiella pneumoniae, preduvijet je za uspješno kontroliranje širenja rezistencije.Antibiotic resistance in enterobacteriaceae has for a long time greatly compromised empirical antibiotic therapy but of greatest concern is the emergence of isolates resistant to all available antibiotics. The Committee for Antibiotic Resistance Surveillance of the Croatian Academy of Medical Sciences and the Ministry of Health Reference Center for Antibiotic Resistance urveillance (RC) at the University Hospital for Infectious Diseases jointly conduct national resistance surveillance as a part of the national strategy coordinated by the Interdisciplinary Section for Antimicrobial Resistance Control (ISKRA). RC collects isolates with rare phenotypes from all over Croatia which enables detection of strains with novel resistance mechanisms: the first plasmid mediated AmpC β-lactamases were described in 2003, the first NDM enzyme in 2009 and the first KPC β-lactamase in 2011. None of these enzymes spread throughout Croatia as yet. Timely recognition of emergence of the new resistant strains, particularly the ones with an epidemic potential like the ST 258 Klebsiella pneumoniae, is a paramount in antibiotic resistance control