Prospective surveillance of bacterial colonization and primary sepsis: findings of a tertiary neonatal intensive and intermediate care unit.

BACKGROUND: Preterm infants and critically ill neonates are predisposed to nosocomial infections as sepsis. Moreover, these infants acquire commensal bacteria, which might become potentially harmful. On-ward transmission of these bacteria can cause outbreaks. AIM: To report the findings of a prospective surveillance of bacterial colonization and primary sepsis in preterm infants and neonates. METHODS: The results of the surveillance of bacterial colonization of the gut and the respiratory tract, targeting meticillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and Gram-negative bacteria from November 2016 to March 2018 were analysed. Bacterial colonization was compared to surveillance of sepsis. FINDINGS: Six-hundred and seventy-one patients were admitted and 87.0 % (N=584) of the patients were screened; 48.3% (N=282) of the patients screened were colonized with at least one of the bacteria included in the screening; 26.2% of them (N=74) had multi-drug-resistant strains. A total of 534 bacterial isolates were found. The most frequently found species were Escherichia coli, Enterobacter cloacae, Klebsiella oxytoca and Klebsiella pneumoniae. Three MRSA but no VRE were detected. The surveillance detected a K. pneumoniae cluster involving nine patients. There were 23 blood-culture-confirmed sepsis episodes; 60.9% (N=14) were caused by staphylococci. Gram-negative bacteria (one Klebsiella aerogenes and two E. cloacae) caused three sepsis episodes which were preceded by colonization with the respective isolates. CONCLUSIONS: Surveillance of colonization provided a comprehensive overview of species and antibiotic resistance patterns. It allowed early detection of a colonization cluster. Knowledge of colonization and surveillance of sepsis is useful for guiding infection control measures and antibiotic treatment.

Fungal epidemiology and diversity in cystic fibrosis patients over a 5-year period in a national reference center.

The knowledge on prevalence rates of yeasts and moulds in patients with cystic fibrosis (CF) in Germany is scarce. The aim of this report is to give an overview of the diversity and epidemiology of fungal species in CF patients. Over a 5-year period, all fungal isolates cultured from microbiological specimen from CF patients were recorded. Beside standard bacteriological culture media two fungal media were used for cultivation. Species were identified by microscopy, biochemical profiling, MALDI-TOF analysis or DNA sequencing methods. In sum, 25,975 clinical samples from CF patients were analyzed. About 75% of CF patients were colonized by yeasts, mainly Candida albicans (38%) and Candida dubliniensis (12%). In 35% of the patients Aspergillus spp. (Aspergillus fumigatus: 29%) were detected, followed by Exophiala dermatitidis and Scedosporium/Lomentospora complex isolates (4% each). Data for other fungal species are shown. Over a 5-year period, the epidemiology of fungal species detected in CF patients was relatively constant. Clinical microbiology laboratories should carefully monitor samples from CF patients for newly occurring fungal pathogens.

Secular trends in nosocomial bloodstream infections: antibiotic-resistant bacteria increase the total burden of infection.

BACKGROUND: It is unknown whether rising incidence rates of nosocomial bloodstream infections (BSIs) caused by antibiotic-resistant bacteria (ARB) replace antibiotic-susceptible bacteria (ASB), leaving the total BSI rate unaffected. METHODS: We investigated temporal trends in annual incidence densities (events per 100 000 patient-days) of nosocomial BSIs caused by methicillin-resistant Staphylococcus aureus (MRSA), ARB other than MRSA, and ASB in 7 ARB-endemic and 7 ARB-nonendemic hospitals between 1998 and 2007. RESULTS: 33 130 nosocomial BSIs (14% caused by ARB) yielded 36 679 microorganisms. From 1998 to 2007, the MRSA incidence density increased from 0.2 to 0.7 (annual increase, 22%) in ARB-nonendemic hospitals, and from 3.1 to 11.7 (annual increase, 10%) in ARB-endemic hospitals (P = .2), increasing the incidence density difference between ARB-endemic and ARB-nonendemic hospitals from 2.9 to 11.0. The non-MRSA ARB incidence density increased from 2.8 to 4.1 (annual increase, 5%) in ARB-nonendemic hospitals, and from 1.5 to 17.4 (annual increase, 22%) in ARB-endemic hospitals (P < .001), changing the incidence density difference from -1.3 to 13.3. Trends in ASB incidence densities were similar in both groups (P = .7). With annual increases of 3.8% and 5.4% of all nosocomial BSIs in ARB-nonendemic and ARB-endemic hospitals, respectively (P < .001), the overall incidence density difference of 3.8 increased to 24.4. CONCLUSIONS: Increased nosocomial BSI rates due to ARB occur in addition to infections caused by ASB, increasing the total burden of disease. Hospitals with high ARB infection rates in 2005 had an excess burden of BSI of 20.6 per 100 000 patient-days in a 10-year period, mainly caused by infections with ARB.

Long-term persistence of MRSA in re-admitted patients.

BACKGROUND: A better knowledge of methicillin-resistant Staphylococcus aureus (MRSA) persistence in hospitalised patients may impact on specific prevention strategies. We have investigated the persistence of MRSA-carriage in patients admitted and re-admitted to a university hospital. PATIENTS AND METHODS: Between January 2002 and October 2005 all MRSA-positive patients admitted to the university hospital of Hannover Medical School were assessed at first admission and all subsequent re-admissions. Patients re-admitted at least once were analysed for the persistence or loss of MRSA. The association of possible factors influencing the persistence of MRSA colonisation or infection (age group, gender, decolonisation therapy during first hospital stay due to MRSA positivity and colonisation of different anatomical sites) was analysed using univariate, multivariate and time-dependent analyses. RESULTS: A total of 1,032 patients who had tested positive at least once for MRSA were admitted to our hospital during the study period, accounting for 2,038 admissions. Of these patients, 403 (39.1%) were admitted more than once (from two times to 21 times), and 238 (59.1%) of the re-admitted patients remained MRSA positive during all subsequent admissions. Fifty-five (13.6%) patients tested MRSA negative at their last admission, and 61 (15.1%) tested MRSA negative at at least two consecutive admissions. In 27 (6.7%) patients, the MRSA status differed more than once between subsequent admissions. Overall, the half-life time (HLT) of MRSA persistence was 549 days, with the duration of persistence dependent on the colonisation of different anatomical sites (HLT only wounds 117 days; HLT mouth, throat, bronchial secretions 627 days; HLT nose, wounds and other body sites 801 days; p < 0.01) and was prolonged if more than one body site was MRSA-positive (HR 2.18, 95% confidence interval 1.52-3.15). CONCLUSION: A detailed knowledge of the dynamics of the loss of MRSA infection could result in a reduction of the incidence of MRSA in the future. Multiple anatomical site carriage of MRSA appeared to predict a prolonged persistence in our cohort of patients re-admitted to a university hospital.

Increasing occurrence of multidrug-resistance in Acinetobacter baumannii isolates from four German University Hospitals, 2002-2006.

BACKGROUND: Acinetobacter baumannii can cause severe infections, mainly in critically ill inpatients. Treatment is complicated by multidrug-resistance (MDR). In Germany, to date, little is known on the extent of MDR in A. baumannii isolated from inpatients in German hospitals and potential factors influencing the emergence of MDR. MATERIALS AND METHODS: We retrospectively analysed the data of A. baumannii isolates from the inpatients of four German university hospitals, tested for antimicrobial resistance with the broth dilution method between 2002 and 2006. We defined MDR as resistance to three or more classes of recommended drugs. After calculating the proportions of MDR in A. baumannii isolates, we investigated the association between MDR in A. baumannii and year of pathogen isolation, hospital, ward type, specimen and demographics.We performed descriptive analysis and multivariable logistic regression. Additionally, proportions of in vitro drug effectiveness against multidrug-resistant and non-multidrug resistant A. baumannii isolates were determined. RESULTS: MDR was found in 66 of 1,190 (5.6%)A. baumannii isolates and increased from 2.1% in 2002 to 7.9% in 2006. The highest proportions of MDR were found in hospital A (8.9%), in intensive care units (7.3%), in isolates from blood (7.6%) and in male patients aged 60 years or older (6.6%). In multivariable analysis, the chance of MDR in A. baumannii isolates increased with the successive years of pathogen isolation (odds ratio [OR] 1.3,95% confidence interval [CI] 1.1-1.5) and there was a higher risk of MDR in A. baumannii in intensive care units(OR 1.8, 95% CI 1.1-2.9). The lowest in vitro antibiotic resistance was found in meropenem, imipenem and ampicillin/sulbactam, with 33, 37 and 39% for multidrug-resistant and 0.4, 1 and 3% in non-multidrug-resistant A. baumannii isolates, respectively. CONCLUSIONS: The increase of MDR in A. baumannii isolates from 2002 to 2006 in four hospitals suggests that clinicians in Germany may expect a rising proportion of MDR inA. baumannii isolates among inpatients. The antimicrobial susceptibility testing of A. baumannii isolates against recommended drugs, combined with in-house antimicrobial resistance surveillance, is needed to ensure appropriate treatment.

Of guinea pigs and men--an unusual case of jaundice.

A 21-year-old male presented at the emergency room with jaundice, itching, dry cough, malaise and weight loss of 10 kg during the preceding four weeks. Eighteen months earlier, the patient had suffered an automobile accident leading to polytrauma. Serological markers for viral or other causes of hepatitis were absent. For suspected secondary sclerosing cholangitis, ultrasound and ERCP were performed but failed to reveal pathological findings. A liver biopsy showed cholestatic liver disease without signs of portal field-associated hepatitis. Hepato-biliary scintigraphy demonstrated hepatocellular dysfunction. The patient finally mentioned his guinea pig farm with around 50 animals, 20 of which had recently died for unknown reasons. The patient and three of his guinea pigs were subsequently tested for serological evidence of leptospirosis. IgG and IgM antibodies reacting with Leptospira interrogans were detected in the patient's serum, and all 3 guinea pigs were serologically positive for serovar Bratislava. Bacterial culture was not successful, and also PCR tests remained negative. The clinical symptoms quickly resolved after the initiation of antibiotic therapy with amoxicillin.

Surveillance of extended-spectrum beta-lactamase-producing bacteria and routine use of contact isolation: experience from a three-year period.

The usefulness and applicability of isolation precautions were questioned for extended-spectrum beta-lactamase (ESBL)-producing strains of Enterobacteriaceae in the endemic setting. We performed a surveillance programme for ESBL-positive organisms and the infection control management of patients colonized or infected with these organisms. Between 1 January 2002 and 31 December 2004, a total of 147 cases of ESBL-producing strains of Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis from 123 patients were noted. The overall incidence of ESBL-producing-strain-positive cases was 0.12/1000 patient-days. The proportion of referred cases was 35% (N=51); 65% of cases (N=96) were acquired in our institution. Infections developed in 57 cases (38.8%), of which 36 (63.3%) were nosocomial. Contact isolation precautions were carried out for 79.6% of the cases, with a median duration of contact isolation precautions for 14 days (range: 0-144). The contact isolation precautions resulted in 2985 isolation days in total, i.e. 995 isolation days per year. Typing by pulsed-field gel electrophoresis showed clonal diversity in 94.2% of the isolates from patients. Seven patient-to-patient transmissions were noted. Only in 10 cases (6.8%) was colonization with ESBL-producing strains cleared. Considering the large number of immunocompromised patients treated in our institution (>1500 bone marrow or solid organ transplantations performed during 2002-2004), we will continue to isolate patients who are colonized or infected with ESBL-producing organisms.

[Tetanus vaccination in the accident and emergency department]. / Tetanusprophylaxe in der Notaufnahme.

While tetanus is a rare disease in industrialized countries, this infectious disease is still responsible for up to 1,000,000 deaths per year in the developing world. In Germany, the introduction of a country-wide vaccination program (STIKO) has led to a decrease in the frequency of tetanus infection from 115 cases per year in the 1960s to fewer than 15 cases per year in the years from 1990 to 2000. In spite of all the treatment now available, tetanus infection still has a lethal outcome in up to 40% of cases. The Robert-Koch Institute recommends active or passive vaccination depending on the wound classification and the patient's current vaccination status. Since when patients have multiple trauma the emphasis while they are being treated for shock is on stabilisation and diagnosis, there is a real risk of underestimating the size and the level of contamination of existing wounds. Since it is not possible to ascertain the patient's vaccination status in most cases, we recommend simultaneous immunization of polytraumatized patients with skin lesions using Tetanol-Tetagam early in the course of the diagnostic procedures while the patients are still in the emergency room.

[Control of methicillin-resistant S. aureus by active surveillance. Results of a workshop held by the Deutsche Gesellschaft für Hygiene und Mikrobiologie]. / Prävention von Methicillin-resistentem S. aureus durch Screeninguntersuchungen. Ergebnisse eines Workshops der Deutschen Gesellschaft für Hygiene und Mikrobiologie.

In Germany, methicillin-resistant S. aureus (MRSA) is increasing continuously. To control the spread of MRSA, active surveillance and admission screening are recommended. In most cases, screening cultures of patients at risk for MRSA will be sufficient. Screening of all patients admitted to an ICU is cost-effective when the incidence of MRSA and nosocomial MRSA infections is high (>2 cases/100 patients and 0.3 MRSA infections/100 patients, respectively): Under these circumstances, a decrease in the incidence of nosocomial MRSA infections of 50% leads to cost-effectiveness at costs of 16 Euro/sample (including subsequent costs). If the incidence of nosocomial MRSA infections decreases by 75%, costs of 24 Euro/sample (including subsequent costs) are cost-effective. If the incidence of MRSA is high, screening by PCR may be cost-effective for patients at high risk for MRSA, especially if they are isolated prophylactically. Recently, PCR methods have been developed which allow the specific identification of MRSA even from nasal swabs.

[Bacterial pathogens, resistance patterns and treatment options in community acquired pediatric urinary tract infection]. / Bakterielle Erreger, Resistenzentwicklung und Behandlungsoptionen beim ambulant erworbenen Harnwegsinfekt im Kindesalter.

BACKGROUND: Epidemiology and resistance patterns of bacterial pathogens in pediatric UTI show large interregional variability and rates of bacterial resistances are changing due to different antibiotic treatment. We intended to evaluate data from northern Germany. PATIENTS AND METHODS: In 100 children (53 female, 47 male, mean age 4.4 +/- 4.2 years) with community acquired UTI, who presented in the emergency department of our medical school from 2000 - 2002, urine cultures were performed. Inclusion criteria were: acute voiding symptoms, significant bacteriuria with growth of at least 10 (5) colony-forming units/ml urine, leukocyturia > 50/ micro l. Exclusion criteria were underlying renal diseases, anatomic abnormalities of the urinary tract, age < 2 months and recurrent UTI. RESULTS: Patients presented with a mean rectal temperature of 38.6 +/- 1.3 degrees C, mean CRP of 66 +/- 68 mg/dl, mean WBC 13 500 +/- 5 600/ micro l and mean urinary leukocytes of 425 +/- 363/ micro l. In urine cultures E. coli was found in 47 % of the cases, Enterococcus faecalis 23 %, Proteus mirabilis 8 %, Klebsiella oxytoca 4 %, Pseudomonas aeruginosa 5 % and others 13 %. In 76 % one and in 24 % two different bacterial species (60 % Enterococcus faecalis) were cultured. Mean resistance rates were in all bacteria (in E. coli): Ampicillin 53 % (69 %), Ampicillin and Sulbactam 51 % (61 %), Cefalosporin 1 (st) generation (Cefaclor) 48 % (24 %), Cefalosporin 2 (nd) generation (Cefuroxim) 40 % (3 %), Cefalosporin 3 (rd) generation (Cefuroxim) 33 % (0 %), Tobramycin 30 % (2 %), Ciprofloxacine 0 %, Cotrimoxazole 40 % (42 %), Nitrofurantoin 12 % (0 %). CONCLUSION: The resistance rates to Ampicillin (+/- Sulbactam) did not increase as compared to previous analyses (1990 - 1995), however, resistance rates to Cotrimoxazole and 1 (st) generation Cefalosporines increased about 20 %. We conclude that the policies for treatment of UTI in children should be re-evaluated every 5 years according to local resistance rates.

[Legionella prevention in intensive care units]. / Legionellenprävention auf Intensivstationen.

From time to time hospitals are in the focus of the local and national media because of cases of nosocomial Legionnaires' disease. In particular intensive care patients are a risk group because of their high amount of immunocompromised patients with an increased risk of developing a Legionellosis. Therefore it is an important aim to maintain an effective prevention system. Nevertheless in some hospitals legionella can be identified. Particularly in these hospitals a high level of attention is required to recognize cases of legionellosis and to take adequately steps to avoid outbreaks of legionellosis. The following article explains the recently published recommendations of the American hospital hygiene experts.

Evaluation of the Merlin, Micronaut system for automated antimicrobial susceptibility testing of Pseudomonas aeruginosa and Burkholderia species isolated from cystic fibrosis patients.

Since accurate antimicrobial susceptibility testing of bacterial cystic fibrosis isolates is known to be problematic and an optimal in vitro testing method has not yet been evaluated, the study presented here was conducted to compare the performance of the reference agar dilution method and broth microdilution with a commercially available automated susceptibility test system (Merlin; Micronaut, Germany). In this pilot study, the susceptibility of 70 clinical strains of Pseudomonas aeruginosa and Burkholderia cepacia-like organisms to nine antimicrobial agents was tested using these methods. Susceptibility results generated by broth microdilution (both automated and according to the National Committee for Clinical Laboratory Standards recommendations) were demonstrated to be of good reproducibility, and they compared favourably to the time- and material-consuming standard agar dilution reference method, especially after a prolonged incubation time (48 h).

Septic shock after liver transplantation for Caroli's disease: clinical improvement after treatment with C1-esterase inhibitor.

The extent of complement and contact activation is related to outcome in sepsis. A low functional index of their main blocker C1-esterase inhibitor (C1-INH) is considered as a relative deficiency of C1-INH and might contribute to the development of fatal complications in the intensive care unit. The first results of therapeutic intervention with C1-INH concentrate in septic shock are promising. We report on our experience of C1-INH concentrate administration in a young woman with Caroli's disease as ultimate rescue therapy for septic shock with capillary leakage syndrome after combined liver and kidney transplantation. No focus of infection was detectable and thus surgical intervention was not indicated. Antibiotic therapy at that time included vancomycin, tobramycin, meropenem and fluconazol. Hemodynamic stabilization occurred within hours after administration of C1-INH concentrate. Simultaneously a reduction in vasopressor medication was possible and negative fluid balance was achieved.

Necrotising enterocolitis: is there a relationship to specific pathogens?

UNLABELLED: Outbreaks of necrotising enterocolitis (NEC) have often been related to specific pathogens such as Enterobacteriaceae. This relationship, however, remains uncertain because of the retrospective nature of the studies addressing this issue. We performed a prospective study to investigate whether there is indeed an association between NEC and specific pathogens. Between April 1993 and March 1997, stools of neonates of < 36 weeks admitted to our neonatal unit were investigated for bacteria in weekly intervals. Clinical and bacteriological data from each infant who developed NEC were compared with those from two control infants matched for gestational age and date of admission. Eighteen infants developed 19 episodes of NEC (clinical signs + air in portal vein); 8 of these had laparotomy; two died. Occurrences of NEC were homogeneously distributed over the 4-year study period. The only significant differences in the clinical course prior to NEC were a more severe stage of respiratory distress syndrome [median 2 (0-4) vs. 0 (0-3), P < 0.05] and a higher proportion of infants who had only been formula fed (63 vs. 32%, P < 0.05) in the cases. Within the last week prior to NEC, potentially pathogenic bacteria were identified in stools of all cases and 79% of controls (P < 0.05). However, there was no significant difference in the occurrence of specific pathogens or groups of pathogens in cases compared with controls. CONCLUSION: Although gut colonisation with potential pathogens appeared to be a prerequisite for the development of NEC, there were no specific bacteria associated with this disease if data from infants with NEC were compared with those from time- and gestational age-matched controls.

Molecular cloning and functional expression of bacteriophage PK1E-encoded endoneuraminidase Endo NE.

Homopolymeric alpha-2,8-linked sialic acid (PSA) has been found as a capsular component of sepsis- and meningitis-causing bacterial pathogens, and on eukaryotic cells as a post-translational modification of the neural cell adhesion molecule (NCAM). The polysaccharide is specifically recognized and degraded by a phage-encoded enzyme, the endo-N-acetylneuraminidase E (Endo NE). Endo NE therefore has become a valuable tool in the study of bacterial pathogenesis and eukaryotic morphogenesis. In this report we describe the molecular cloning of Endo NE and the expression of a functionally active recombinant enzyme. The cloned DNA sequence (2436 bp) encodes a polypeptide of 811 amino acids, which at the 5' end contains a totally conserved neuraminidase motif. Expressed in Escherichia coli, the enzyme migrates as a single band of approximately 74 kDa in SDS-PAGE. A central domain of 669 amino acid residues is about 90% homologous to the recently cloned Endo NF. Both phage-induced lysis of bacteria and the catalysis of PSA degradation by the recombinant enzyme are efficiently inhibited by a polyclonal antiserum raised against the intact phage particle. The C-terminal region seems to be essential to enzymatic functions, as truncation of 32 amino acids outside the homology domain completely abolishes Endo NE activity. Our data also indicate that the 38 kDa protein, previously assumed to be a subunit of the Endo NE holoenzyme, is the product of a separate gene locus and is not necessary for in vitro depolymerase activity.

[Introduction of an infection registration program for surgical wound infection based on the WHOCARE software of WHO]. / Einführung eines Infektionserfassungsprogramms für chirurgische Wundinfektionen auf der Basis der WHOCARE-Software der WHO.

Surveillance of surgical wound-infection (SWI) is an important instrument in the internal and external quality control in surgery. In the past it has been shown that statistics on surgical wound infection are helpful for reduction of wound infection rates. With the engagement of nurses for clinical hygiene at our hospital we had the possibility to evaluate programs for surveillance of nosocomial infection. In a pilot study we began with the surveillance of SWI. The set of data registered was defined by WHOCARE, the software-package used in the study which is distributed by the WHO Europe. Criteria of the NNIS-Study for SWI were applied. Between March and December 1992 approximately 1.300 surgical interventions had been registered. Although the dataset in WHOCARE is limited with regard to an easy surveillance, it was possible to find out infection rates dependent on all major parameters. Additionally reports on individual infection rates and tables containing information of infected cases were sent to every surgeon. By analyzing some of the problems detected during the study, we developed an improved protocol for routine surveillance of SWI. In the future it will save time and will allow the best quality of collected data in narrow collaboration between the departments of microbiology, clinical hygiene and surgery. This protocol should be transferable to other hospitals and represents an anticipated precautious measure with regard to legal regulations on quality control in medicine.

[Botulism in infancy. A rare cause of floppy infant syndrome]. / Säuglings-Botulismus. Eine seltene Ursache des Floppy-infant-Syndroms.

In Europe only a few cases of infantile botulism have been identified. A two month old infant fell ill with feeding difficulties and profound general weakness. Clostridium botulinum and botulinal toxin, the causative agents, were isolated from the patients stool. We describe the typical clinical symptoms and the investigations confirming the diagnosis.

Cervical lymphadenitis in a child caused by a previously unknown mycobacterium.

Acid-fast bacilli were isolated from lymph nodes of an immunocompetent child presenting with unilateral cervical lymphadenitis. The slowly growing mycobacterium could not be identified by traditional methods. Direct sequencing of the enzymatically amplified 16S rRNA gene revealed a unique sequence belonging to a previously unrecognized mycobacterium. Direct 16S rDNA sequencing enables definitive identification of mycobacterial isolates. The method is useful for rapid recognition of previously unrecognized pathogens.