MANAGEMENT OF KLEBSIELLA PNEUMONIAE KPC OUTBREAK IN INTERNAL MEDICINE

Acta Medica Mediterranea, 2016, 32: 823 MANAGEMENT OF KLEBSIELLA PNEUMONIAE KPC OUTBREAK IN INTERNAL MEDICINE ANDREA BELLODI 1*, LISETTE DEL CORSO 1, SERENA FAVORINI 1, ELISA MOLINARI 1, ERIKA COPPO 2, GIOVANNI ORENGO 3, VALERIO DEL BONO 4, RICCARDO GHIO 1, ELEONORA ARBOSCELLO 1 1 Clinic of Internal Medicine 3 IRCCS AOU San Martino IST, Genoa, Italy - 2 Microbiology IRCCS AOU San Martino IST, Genoa, Italy - 3 Clinic Risk and Quality Management, IRCCS AOU San Martino IST, Genoa, Italy - 4 Clinic of Infectious Diseases IRCCS AOU San Martino IST, Genoa, Italy ABSTRACT Introduction: Italy has a high incidence of Klebsiella pneumoniae producing carbapenemase (CRKP) infections. We report and discuss the experience of our Centre, an Internal Medicine Unit in North-Western Italy, focusing on the high clinical challenge dealing with this infections in year 2012 with data expanded over three years of surveillance Materials and methods: we retrospectively analyzed data of patients with isolation of CRKP during years 2011 2013. Results: In 2011 2 patients had positive cultures for CRKP; in 2012 CRKP was isolated in 21 patients. The mean age of the cohort was 77,6 (range 52-89). Cultures were positive in different specimens: urines 71,4%, blood 9.52%, upper respiratory tract 9.52%, wounds 9,52%. Most relevant infection-associated risk factors were identified in presence of devices such as urinary catheter (UC) (76% of patients) or central venous catheter (CVC) (47% of patients). In 2013 we observed 6 cases. Cultures were positive on urines, blood and abdominal drainage, blood, sputum and bronchial-alveolar lavage. In conclusion, in three years of surveillance we observed 29 patients with CRKP isolation: 17 urinary tract infections (response 6/13), 4 blood stream infections (response 1/3), 4 respiratory tract infections (response 1/3), 4 skin and soft tissue infections/colonization (not treated); crude mortality was 51% and global response to therapy was 42,1% on 19 treated patients. Conclusions: the 2012 outbreak was contained and the major awareness of the problem produced systematic new measures for infection control: screening with rectal swab for CRKP for patients admitted from other Hospitals or wards, sudden isolation of colonized/infected patients, more accurate attention to environmental and personal hygiene. CRPK is an important cause of morbidity and mortality; efficiency of single agent antibiotic therapy against CRPK seems to be not satisfying. Dedicated guidelines of new combination therapy are required. Key words: Klebsiella pneumoniae KPC, carbapenemase, antibiotic resistance, outbreak, internal medicine, infection control. DOI: 10.19193/0393-6384_2016_3_97 Received Febrary 13, 2016; Accepted April 02, 2016 Introduction Klebsiella pneumoniae producing carbapenemase (CRKP) is one of the most fearful enemy for healthcare providers. First cases were described in the United States in 2001 from a strain isolated in 1996 (1). Carbapenemase (KPC) is a type of beta lactamase resistant to all beta lactam antibiotics, including carbapenems. KPC enzymes are located on plasmids (2) ; currently 10 variants of KPC have been discovered. Other gram-negative species (such as Escherichia coli, Proteus mirabilis, Enterobacter species, Salmonella enterica, Citrobacter freundii, Serratia species, Pseudomonas species and Acinetobacter baumannii) can carry these type of enzymes (3). Giani et al described the first case in Italy in 2008, with the isolation of KPC 3 with corresponding gene located on transposon tn4401, the same reported from some Israeli isolation (4). The current epidemiological data in Europe shows a sit-

824 Andrea Bellodi, Lisette Del Corso et Al uation even worse than expected in the early 2000: the numbers of the infections are near to pandemics, especially in Italy, Greece and Israel. Fortunately not all individuals who have contact with CRKP develop infection, sometimes just the colonization occurs (5). Inappropriate antibiotics therapies, travels and poor hygienic measures seem to be determinant elements that brought to such a spread of worldwide cases. Here we report and discuss the experience of our center, an Internal Medicine Unit in Italy, focusing on the high clinical challenge dealing with this infections across year 2012 and 2013. Materials and methods Setting San Martino Hospital is the largest acute tertiary care hospital in Liguria, Italy, with a total capability of about 1400 beds. Patients involved in the study derived from a single ward, the Clinic of Internal Medicine 3. This ward has a capability of 27 beds, with an annual number of admitted patients of about 750. Data are collected from January 2011 to December 2013 and they are analyzed retrospectively. Patients came from Emergency Care Unit or other units, especially Hematology and Surgery. Infection control policy did not include routine surveillance cultures or screening of high risk patients at the beginning of the examined period. Hand hygiene measures, personal protection equipment for infection control and regular room cleaning are mandatory in the Hospital. Antibiotic drugs monitoring is required for carbapenems, polymixins, tigecyclin, linezolid, vancomycin. Patients signed informed consent for data treatment. Bacterial identification All strains were identified in our Microbiology Centre with standard microbial methods and semiautomated Vitek-2 system provided confirmation and susceptibility testing. Results of susceptibility testing were interpreted according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) clinical breakpoints (6). In particular carbapenems susceptibility was considered with Minimum Inhibitory Concentrations (MIC) 2 mg/l and resistance with MIC 8 mg/l. Determination of enzyme type was obtained in some isolation. The modified phenotypic Hodge test was performed for isolates that exhibited reduced susceptibility to imipenem or meropenem on disk diffusion (zone of inhibition diameter 23 mm), as recommended by CLSI (7). The presence of blakpc-3 was confirmed by polymerase chain reaction (PCR) amplification using the primers KPC-F (5ʹ -ATGTCACTGTATCGCCGTCT-3ʹ ) and KPC-R (5ʹ -TTTTCAGAGCCTTACTGCCC-3ʹ ) using heat-extracted DNA as a template (8). For genotyping, random amplification of polymorphic DNA (RAPD) PCR was performed using the primer 1254 (5ʹ -CCGCAGCCAA-3ʹ ), as described previously (9). Study endpoint We collected isolations of CRKPs in order to describe characteristics of infected patients and their outcome. We evaluated epidemiologic data, patient s related morbidities and response to antibiotic therapies. The endpoint was to have a better comprehension of the phenomenon and describe retrospectively how we managed an outbreak in year 2012. Results In 2011 only 2 patients had positive cultures for CRKP; they were elderly male patients (age 81 and 88) both with multiple risk factors for hospital related infections (diabetes mellitus II, bed resting syndrome, neurological impairment); cultures were positive on pre-sacral wounds: patients were considered colonized and did not receive any systemic antibiotic therapy, with no impact on mortality. In 2012 we reviewed a total of 57 isolations among 21 patients. The mean age of the cohort was 77,6 (range 52-89), 6 males, 15 females. Cultures were positive in different specimens (percentages referred to infections/patients): urines 71,4% (15/21), blood 9.52% (2/21), upper respiratory tract 9.52 % (2/21), wounds 9,52% (2/21). One patient with a urinary tract infection (UTI) treated with success with gentamycin, died ten months later with CRKP bloodstream infection (post-mortem report). All isolations were hospital related (after at least 72 hours from the admission). Comorbidities analyzed were heart failure (HF), diabetes mellitus (DM), chronic obstructive pulmonary disease (COPD), solid tumors, hematological malignancies, renal failure and liver dysfunction; five patients had no comorbidities, five had one. The number of patients who had two or more comorbidities was eleven; most prevalent comorbidities were HF (8

Management of Klebsiella pneumoniae KPC outbreak in internal medicine 825 pts), hematological malignancies (8 pts, 1 multiple myeloma, 4 non-hodgkin lymphomas, 1 myelodisplastic syndrome, 1 primary myelofibrosis, 1 acute lymphoblastic leukemia), DM and renal failure (both 7 pts). Other patients presented solid tumors (4 pts), COPD (2 pts), liver dysfunction (1 pt). Most relevant infection-associated risk factors were identified in presence of devices such as urinary catheter (UC) (76% of patients) or central venous catheter (CVC) (47% of patients). Antibiotic therapy was tailored on the single patient and the choice of the drug was defined together with Infectious Disease Specialist. Six patients considered colonized or in poor general conditions were not treated (two patient with isolation from wounds, one from sputum and three from urines). Response to therapy was considered with clinical conditions and negativity of at least two consecutive cultures. Drug used were: gentamycin (response 4 out of 11), colistin plus tigecyclin (response 0 out of 1), colistin (response 0 out of 1), piperacillin/tazobactam (response 0 out of 1), fosfomycin (response 0 out of 1), amikacin (response 1 out of 1), combination therapy with colistin plus gentamyicin plus tigecyclin (response 1 out of 1). Response to therapy was 40% in treated patients. Overall crude mortality of the 2012 cohort was 47%. In vitro colistinresistance was present in 23.7% of the isolations. One patient received more than one line of therapy without success (fosfomycin, gentamycin and colistin). In 2013 we observed a decreasing number of isolations with 6 cases. Four patients carried a hematologic malignancy; infections risk factors were represented by devices: one patient had UC, one had CVC, two patients had both UC and CVC, one patient had UC, CVC and an abdominal drainage; only one patient did not have any device. Cultures were positive on urines (two patients), blood and abdominal drainage (one patient), blood (one patient), sputum (one patient) and bronchial-alveolar lavage (one patient). Two patients did not receive any treatment (one patient with poor general conditions and one patient with blood cultures resulted positive post mortem). The other patients received antimicrobial therapy: gentamycin (response 1 out of 1), gentamicin plus meropenem (response 0 out of 1), gentamycin plus high dose meropenem plus tygeciclin (response 0 out of 1), gentamycin plus high dose meropenem plus tygeciclin plus inhaled colistin (response 1 out of 1, patient affected by CRKP severe pneumonia). The response rate was 50% and overall mortality of 2013 patients was 33.3%. In conclusion, in three years of surveillance we observed 29 patients with CRKP isolation: 17 urinary tract infections (response 6/13), 4 blood stream infections (response 1/3), 4 respiratory tract infections (response 1/3), 4 skin and soft tissue infections/colonization (not treated); crude mortality was 51% and global response to therapy was 42,1% on 19 treated patients. Patient treatments can be seen in Table 1. Discussion Urinary tract infections (n17) Type of infection (n pts responders/n pts treated) Bloodstream infections (n4) Respiratory tract infections (n4) Skin and soft tissue infections/colonizations (n4) Gentamycin 5/10 0/0 0/1 0/0 Amikacin 1/1 0/0 0/0 0/0 Piperacillin/tazobactam 0/1 0/0 0/0 0/0 Fosfomycin 0/1 0/0 0/0 0/0 Colistin 0/1 0/0 0/0 0/0 Gentamycin + meropenem 0/0 0/0 0/1 0/0 Colistin +Tigecyclin 0/0 0/1 0/0 0/0 Colistin + Gentamycin + Tigecyclin Meropenem HD + Gentamycin + Tigecyclin Meropenem HD + Gentamycin + Tigecyclin + inhaled Colistin 0/0 1/1 0/0 0/0 0/0 0/1 0/0 0/0 0/0 0/0 1/1 0/0 No therapy 4 1 1 4 Table 1: Antibiotic therapy related to source of infection. Treatment was decided and tailored on the single patient. A single patient could have been treated with more than one line. According to clinical data, not every patient was treated. (Note HD = high dose, 2 or 3 grams three times a day). In Europe until 2009, CRKP spread was limited to Greek and Cyprus. In 2010 Italy became heavily involved with prevalence in the invasive isolation of about 15%. From the first case described from Giani, other Italian isolations showed the presence of KPC type 2 and even worse, the appearance of horizontal transmission of

826 Andrea Bellodi, Lisette Del Corso et Al colistin-resistant KPC-3 positive CRKP in Palermo in 2011. Data collected from EARS net report a dramatic increase of carbapenem-resistance from 2006 to 2011 (1-2% to near 30%) (10,11). As for our ward, the situation was controlled until 2012. In 2011 only 2 patients had positive cultures for CRKP; except for the first four sporadic cases from December 2011 to May 2012, all 2012 isolations were collected after an index case, a female patient affected by tetanus, who had prolonged stay in ICU and was transferred to our unit in May 2012. She had multiple devices: UC, CVC and tracheostomy; she also had bed rest syndrome with cognitive impairment determining total dependence on health care personnel. During her hospitalization in ICU she was colonized with multiple nosocomial bacteria, such as Acinetobacter baumannii and CRKP. Cultures were positive in urine and aspiration from tracheostomy. Nursing management was quite demanding. After that, in the second half of the year, number of CRKP isolation dramatically increased taking the proportion of a real outbreak. Infection control measures were taken after two consecutive cases in June 2012. Timeline of isolations can be seen in Figure 1. Figure 1: CRKP isolations timeline. Infected patients were isolated in a single room or transferred to Infectious Disease Unit when possible; cohorts of positive patients were disposed when necessary. Physicians and all health care operators were informed about the situation and strict hygienic measures were adopted: more accurate hand hygiene with chlorine bases soap, accurate room and furniture cleaning and disinfection with chlorexidine and alcoholic agents after discharge of a positive patient, screening of other patients at risk of contamination with rectal swab. CRKP isolations in 2013 were still high in comparison of 2011, but the 2012 outbreak was contained and the major awareness of the problem produced systematic new measures for infection control: screening with rectal swab for CRKP for patients admitted from other Hospitals or wards, sudden isolation of colonized/infected patients, more accurate attention to environmental and personal hygiene (application of personal protection devices such as single use gloves and cloaks, disinfection with chlorine agents). Progressive gain in resistance of the isolated strains is another matter of concern. During autumn 2012 strains with low susceptibility to colistin became more frequent, probably due to the antibiotic selective pressure. The bacteria showed high capability to adapt to antibiotics. Tumbarello and colleagues recently demonstrated the superior efficacy of combination therapy in CRKP blood stream infections; in particular, their experience on 125 patients, showed that mortality of patients treated with monotherapy (colistin or tygeciclin) compared to patient treated with combination therapy with carbapenem was significantly higher (66,7% vs 12,5%) (12). As for our experience we can only make observation on small number of patients, but it is interesting to observe that in one particular patient, CRKP showed progressive resistance to every single antibiotic administrated to eradicate the infection (fosfomicyn, gentamicin and then colistin); therefore combination therapy seems to be the better choice, especially for most severe cases. Maybe a little space for single agent therapy could be reserved to aminoglycosides: data on 55 patients from 15 different papers demonstrates a response rate to aminoglycosides treatment of about 75%(13). Gentamycin and amikacin response rate in our cohort was 6 out of 12; more data are needed to better define the efficacy of monotherapy, which can be an option in selected patients. It is important to underline that patients treated with combination therapy in our experience had a good result even if their infections were severe (bloodstream infection and pneumonia, both patients with hematological malignancies); unfortunately we have no statistic prove to support these hypothesis, but, even according to current literature, combination therapy with colistin plus tygeciclin, high dose carbapenems and aminoglycosides, is a chance of life sparing treatment in CRKP infections, thus not yet codified in dedicated guidelines. Another matter of interest deals with patients without signs of infection that resulted positive for CRKP intestinal colonization. Should we discharge these patients home or try to eradicate the coloniza-

Management of Klebsiella pneumoniae KPC outbreak in internal medicine 827 tion? Is a strategy of eradication cost-effective? According to our opinion at least a chance to eradicate CRKP is mandatory in patient receiving immune-chemotherapy or surgery; mortality related to a potential infection in these patients is relevant. Oral gentamycin seems to be an option for these patients, with promising results at least in a short period of time (14). As for other patients, a local registry of CRKP carriers could be an interesting option in order to give further information to clinicians that could be involved in the management of these patients. This approach could spare costs of drugs, comorbidities, days of hospitalization and infection of other patients. Conclusion Klebsiella pneumoniae KPC is an important cause of morbidity and mortality; efficiency of single agent antibiotic therapy against CRPK seems to be not satisfying. Furthermore colistin resistance is another important matter of concern: combination therapy could be a valid option to eradicate CRKP and avoid development of other resistance. Dedicated guidelines of new combination therapy are required to have a more rapid and accurate management of these severe infections. Moreover, we suggest a carbapenem-sparing strategy when possible in order to reduce the incidence of new carbapenemase producing bacteria. Finally, a severe strategy of surveillance and containment of infected patients with strict hygiene procedures is required to avoid dissemination and hospital outbreaks. References 1) Yigit H, Queenan AM, Anderson JG, Domenech- Sanchez A, Biddle JW, et al. Novel carbapenemhydrolyzing beta lactamase KPC-1 from a resistant strain of Klebsiella Pneumoniae. Antimicrob agents chemother 2001; 45: 1151-61. 2) Nordmann P, Cuzon G, Naas T. The real threat of Klebsiella Pneumoniae carbapenemase producing bacteria. Lancet Infect Dis 2009 apr; 45(4): 228-36. 3) Arnold RS, Thom KA, Sharma S, Phillips M, Kristie Johnson J, Morgan DJ. Emergence of Klebsiella pneumoniae carbapenemase producing bacteria. South Med J 2011 Jan; 104(1): 40-5. 4) Giani T, D Andrea MM, Pecile P, Borgianni L, Nicoletti P, et al. Emergency in Italy of Klebsiella Pneumoniae sequence type 258 producing KPC-3 carbapenemase. J Clin Microbiol 2009; 47: 3793-4. 5) Endimiani A, Depasquale JM, Forero S, Perez F, Hujer AM, et al. Emergency of blakpc-containg Klebsiella Pneumoniae in a long-term acute care hospital: a new challenge to our healthcare system. J antimicrob chemother 2009; 64: 1102-10. 6) European Committee on Antimicrobial Susceptibility Testing (EUCAST). Clinical breakpoints. EUCAST. [Accessed 12 jan 2013]. Available at: http://www.eucast.org/clinical_breakpoints 7) Clinical and Laboratory Standards Institute Performance Standards for Antimicrobial Susceptibility Testing of Anaerobic Bacteria: Informational Supplement. Clinical and Laboratory Standards Institute CLSI, Wayne, PA (2010). Available at: http://www.clsi.org 8) Bradford PA, Bratu S, Urban C, Visalli M, Mariano N, et al. Emergence of carbapenem-resistant Klebsiella species possessing the class A carbapenem-hydrolyzing KPC-2 and inhibitor-resistant TEM-30 beta-lactamases in New York City. Clin Infect Dis 2004; 39 (1): 55 60 9) Nowrouzian F, Hesselmar B, Saalman R, Strannegard IL, Aberg N, et al. Escherichia coli in infants intestinal microflora: colonization rate, strain turnover, and virulence gene carriage. Pediatr Res 2003; 54: 8-14. 10) Annual epidemiological report: Reporting on 2010 surveillance data and 2011 epidemic intelligence data, European Centre for Disease Prevention and Control. Available at: http://www.ecdc.europa.eu/en/publica- tions/publications/annual-epidemiological-report- 2012.pdf 11) Munoz-Price L, Poirel L, Bonomo RA, Schwaber MJ, Daikos GL, et al. Clinical epidemiology of the global expansion of Klebsiella pneumoniae carbapenemases. Lancet Infect Dis 2013; 13: 785-96. 12) Tumbarello M, Viale P, Viscoli C, Trecarichi EM, Tumietto F, et al. Predictors of mortality in bloodstream infections caused by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae: importance of combination therapy. Clin Infect Dis 2012; Oct; 55(7): 943-50. 13) Hirsch EB, Tam VH. Detection and treatment options for Klebsiella pneumoniae carbapenemases (KPCs): an emerging cause of multidrug-resistant infection. J Antimicrob Chmother 2010 Jun; 65(6): 1119-25. 14) Zuckerman T, Benyamini N, Sprecher H, Fineman R, Finkelstein R, et al. SCT in patients with carbapenem resistant Klebsiella pneumoniae: a single center experience with oral gentamicin for the eradication of carrier state. Bone Marrow Transplant 2011 Sep; 46(9): 1226-30. Corresponding author ANDREA BELLODI, MD Clinic of Internal Medicine 3 IRCCS AOU San Martino IST Largo Rosanna Benzi 10 16132, Genoa (Italy)