[Tuberculosis infection control - recommendations of the DZK]. / Infektionsprävention bei Tuberkulose - Empfehlungen des DZK.

The epidemiological situation of tuberculosis (TB) in Germany has improved considerably during the past few years. However, those in unprotected contact with infectious tuberculosis patients frequently and/or over longer periods of time and/or intensively continue to have a higher risk for TB infection. Rapid diagnosis, prompt initiation of effective treatment, and adequate infection control measures are of particular importance to prevent infection. The present recommendations depict the essentials of infection control as well as specific measures in the hospital (isolation, criteria for its duration and technical requirements, types of respiratory protection, disinfection measures, waste disposal). The specific requirements for outpatients (medical practice), at home, for ambulance services, and in congregate settings, including prisons, are also addressed. Compared with the previous recommendations the pattern of respiratory protection measures has been simplified. As a rule, hospital staff and those visiting infectious tuberculosis patients are advised to wear respiratory protection that satisfies the criteria of FFP2-masks (DIN EN 149), while patients should wear mouth-nose protectors (surgical masks) in the presence of others and outside the isolation room. A detailed depiction of criteria for isolation and its duration in smear positive and only culturally confirmed pulmonary tuberculosis has been added.

[Tuberculosis infection control--recommendations of the DZK]. / Infektionsprävention bei Tuberkulose--Empfehlungen des DZK.

The epidemiological situation of tuberculosis (TB) in Germany has improved considerably during the past few years. However, those in unprotected contact with infectious tuberculosis patients frequently and/or over longer periods of time and/or intensively continue to have a higher risk for TB infection. Rapid diagnosis, prompt initiation of effective treatment, and adequate infection control measures are of particular importance to prevent infection. The present recommendations depict the essentials of infection control as well as specific measures in the hospital (isolation, criteria for its duration and technical requirements, types of respiratory protection, disinfection measures, waste disposal). The specific requirements for outpatients (medical practice), at home, for ambulance services, and in congregate settings, including prisons, are also addressed. Compared with the previous recommendations the pattern of respiratory protection measures has been simplified. As a rule, hospital staff and those visiting infectious tuberculosis patients are advised to wear respiratory protection that satisfies the criteria of FFP2-masks (DIN EN 149), while patients should wear mouth-nose protectors (surgical masks) in the presence of others and outside the isolation room. A detailed depiction of criteria for isolation and its duration in smear positive and only culturally confirmed pulmonary tuberculosis has been added.

Infection control in german-speaking burn centres: results of an online survey.

To systematically evaluate which infection control measures are in place in burn units, we conducted an online survey among 43 German-speaking burn units. The 29 units that responded and agreed to publication represented more than 125 patient beds. All units were located in advanced care hospitals. A total of 14 units provided single rooms only, and 22 units had a nurse-to-patient ratio of at least 1:2. Infection control practices included pre-emptive barrier precautions (29 units), the use of sterile filters for tap water supply (29 units), and an antibiotic stewardship program (24 units). Microbial screening of the patients on admission (23 units), regular prevalence screening (26 units) and surveillance of nosocomial infections (21 units) were also widely used. The high reply rate to the survey indicates the special relevance of infection control for burn units. Our survey shows that great efforts and several measures are being undertaken to address infection control challenges in burn patient care, but it also underlines the need for increased interdisciplinary infection control and antibiotic stewardship activities.

Afin d'évaluer les mesures préventives des infections déployées, nous avons réalisé une enquête en ligne auprès de 43 Centres de Traitement des Brûlés germanophones. Les 29 CTB ayant répondu (et accepté la publication) représentent 125 lits. Tous les CTB étaient situés dans des hôpitaux de référence. Quatorze CTB n'avaient que des chambres seules, 22 avaient un ratio infirmière/patient de1/2. Les mesures préventives comprenaient les précautions barrière (29), des filtres aux points d'eau (29), un programme d'évaluation de l'antibiothérapie (24). La cartographie bactérienne à l'entrée (23), la surveillance de la prévalence des infections (26) et des infections nosocomiales (21) étaient aussi régulièrement déployées. Le taux de réponse élevé pour ce type d'étude montre l'intérêt porté à la prévention des infections en CTB. Cette étude montre que les CTB portent une attention particulière à la prévention et à la surveillance des infections. Elle démontre aussi l'intérêt d'une approche multidisciplinaire et de la mise en place de programmes d'évaluation de l'antibiothérapie.

[Demands on surgeons of the Infectious Disease Control Act]. / Anforderungen des Infektionsschutzgesetzes an den Chirurgen.

The German Infectious Disease Control Act of 2001 includes a modified regulation for reporting infectious diseases and infectious pathogens and new clauses for surveillance and infection control in medical institutions. For the first time, all health care facilities are obliged to conduct surveillance of nosocomial infections and multiresistant pathogens. This legal regulation including mandatory monitoring by local health departments aims at reducing the rates of nosocomial infection and frequency and dissemination of highly resistant pathogens. This article describes the effect of the Disease Control Act on surgical departments. Surveillance of postsurgical wound infection should lead to better understanding of the cause and effect of nosocomial infection and greater acceptance of high-quality hospital hygiene management.

In vitro combination-effect of temocillin with ticarcillin and aminoglycosides on gram-negative and gram-positive bacteria.

The in vitro efficacy of temocillin in combination with ticarcillin and with gentamicin, tobramycin, amikacin and netilmicin against 80 Gram-negative and 20 Gram-positive bacterial strains was compared by use of the checkerboard agar dilution technique. No synergistic or additive effect was seen on the Gram-positive strains. Great variations occurred between the different bacterial species, and the temocillin-ticarcillin combination had only little effect against the Pseudomonas strains tested. On average, only 12% of all strains tested were inhibited synergistically by temocillin-gentamicin combinations, and only 7 to 10% by combinations of temocillin with the other aminoglycosides. However, 25% of Gram-negative strains were inhibited synergistically and 40% of Gram-negative strains were inhibited additively by the combination of temocillin-gentamicin.

How to survey nosocomial infections.

Many surveillance methods for nosocomial infections (NIs) have been put forward in the literature, and all have their advantages and disadvantages. Different surveillance methods are useful, depending on whether the objective of surveillance is only to increase sensitivity to infection control problems and to identify areas with possible infection control problems; to confirm a possible infection control problem through comparison with other units or departments; or to use surveillance data for identifying the sources of infections. Furthermore, time effectiveness is a major point in selecting the most appropriate method, particularly the method for case identification. In units or departments with a high level of NI, even highly time-consuming surveillance methods may be ultimately time-effective; in units or departments with a lower level of NI, the time-effectiveness depends on the time necessary for case identification. Close liaison with staff in the units is a sine qua non for the success of all surveillance activities.

Influence of architectural design on nosocomial infections in intensive care units--a prospective 2-year analysis.

Nosocomial infection rates in an old intensive care ward constructed in 1924 were compared with those in a new one constructed in 1986. The nosocomial infection rate in the old unit was 34.2% and that in the new unit 31.9%, with an average of 33%. The most frequent infections were: pneumonia, urinary tract infection, septicaemia and wound infection. After transfer of the intensive care unit (ICU) the incidence and profile of nosocomial infections remained the same. These findings suggest that the influence of architectural design has little impact on the incidence of nosocomial infections.

An epidemiological study assessing the relative importance of airborne and direct contact transmission of microorganisms in a medical intensive care unit.

A prospective epidemiological survey was carried out over a period of seven weeks in a medical intensive care unit. Bacteria from patients, staff and air were monitored and the transmission of isolated microorganisms was followed. Handwashing samples revealed pathogenic bacteria in 30.8% of physicians (average number of colony forming units: 71,300 per hand) and 16.6% of nurses (39,800 cfu per hand). Air cultures yielded pathogens in 15% of sampling periods and nine of 53 patients were found to be colonized with Gram-negative bacteria, Staphylococcus aureus or Candida spp. The spectrum of bacteria recovered from patients and air was generally different, whereas strains recovered from patients and their attendants' hands were indistinguishable on multiple occasions. The results of this study confirm that direct contact is the principal pathway of microbial transmission, whereas little evidence for a significant role of airborne transmission is shown. The call for more extensive air-filtering and ventilation systems in medical intensive care units is not supported by the results shown in this communication.

Penetration of netilmicin into heart valves, subcutaneous and muscular tissue of patients undergoing heart surgery.

In 57 patients undergoing heart surgery concentrations of netilmicin in plasma, heart valves, muscle, and subcutaneous tissue were determined after a 5 min intravenous bolus injection of 1.5 mg/kg body weight. Within 8 h netilmicin serum concentration declined from 3 micrograms/ml to 1 microgram/ml. In heart valves the concentrations during heart surgery were high enough to inhibit most staphylococci, Klebisiella, Enterobacter and Escherichia coli strains. No different serum and tissue concentrations in patients with and without extracorporal circulation could be found.

[Acanthamoebae, Naegleria and other free-living Amoebae in cooling and rinsing water of dental treatment units]. / Acanthamoeben, Naeglerien und andere freilebende Amöben in Kühl- und Spülwasser von Zahnbehandlungseinheiten.

215 water samples were taken from 49 dental treatment units and investigated for the existence of free-living amoebae. In all water-carrying systems of the dental treatment units it was possible to verify the incidence of one or more amoeba species. In 8.2 per cent of the units Naegleria species was found and in 12.2 per cent Acanthamoeba species was present. Seven Naegleria and six Acanthamoeba strains (2 A. castellanii and 4 A. polyphaga) were isolated. From samples originating from 12 dental treatment units (DTU) another 42 amoeba strains were isolated which consisted of 14 different species within 9 classes. Among them Vannella mira (in 19 per cent of samples) and Hartmannella vermiformis (10.6 per cent) were found to be the most frequent species, followed by H. cantabrigensis (9.5 per cent), V. platypodia, Platyamoeba stenopodia and V. simplex (7.1 per cent each). In 10 per cent of samples monotrichous and bitrichous flagellates such as the Bodo species were found, whereas two samples contained ova, larvae and adult free-living nematodes. Among the isolated Naegleria strains no thermophilic strain was present. Consequently they belong to the N. gruberi complex. Among the Acanthamoebae five of the six strains were thermophilic. All strains were investigated for pathogenic properties by means of the mice inoculation test. Two strains proved pathogenic - it was possible to isolate them from the brain and lung of dead mice. Another two strains proved to have invasive properties because they were isolated from the brain of infected animals; however, they did not give rise to disease or death of the respective animals. Supplementary microbiological tests demonstrated the existence of bacteria and fungi in 84 per cent of dental treatment units. Pseudomonas spec. were detected in 75% of dental units, Serratia marcescens in 2% and fungi in nearly 3%. 58.3% of all water samples contained total germ counts of more than 100/ml.

Proven and unproven methods in hospital infection control in intensive care units.

Most common nosocomial infections in Intensive Care Units are: respiratory tract infections, urinary tract infections, bacteremias, and wound infections. Proven methods in hospital infection control are: hand washing, discipline of all personnel, appropriate nursing techniques, specially trained hygiene staff, isolation, appropriate number of nursing personnel per patient, appropriate use of antibiotics, few and brief usage of foreign bodies such as intravenous lines. Useless and unproven methods in hospital infection control are: environmental cultures, routine cultures of personnel, routine air sampling, fogging and spraying of disinfectants, UV lights, plastic shoe covers, routine floor disinfection, disinfection or sticky mats, change of humidifiers and tubings every eight hours, and systematic antibiotic prophylaxis against pneumonia.

[Importance of mycoses in intra-abdominal infections]. / Stellenwert der Mykosen bei intraabdominalen Infektionen.

Although there is a 20% yeast colonization in the gastrointestinal tract of the population, fungal infections appear only rarely in secondary peritonitis. The risk of severe mycosis increases after a major operation and when a patient is taking broad-spectrum antibiotics, is on total parenteral nutrition, is catheterized, and/or is immune-suppressed. In the past years the incidence of nosocomial fungal infections (usually Candida spp.) has risen significantly. Five percent of CAPD-related peritonitis is caused by fungi. In enteral anastomosis breakdown, invasive mycosis occurs more often, with an accompanying lethality of up to 80%. In severe pancreatitis, up to 5% of peripancreatic necrosis is infected with fungi. The clinical course of severe mycosis, like the septic syndrome, is associated with fungemia in up to 50% of cases. As most of the facultative pathogenic fungi are part of the physiological flora, it is difficult to interpret mycological cultures. In order to diagnose invasive fungal infections, histopathological techniques and serologic tests for antigens and antibodies are available. Three antifungal agents (amphotericin B, flucytosine, fluconazole) are available for intravenous administration. Amphotericin B is given at doses of up to 1 mg/kg per day, in liposomal galenism up to 3 mg/kg per day. Combining amphotericin B with flucytosine (150-200 mg/kg per day) a synergistic effect is reached. Fluconazole at a dosage of 200-800 mg per day represents an alternative with similar antifungal activity and lower side effects.

[Antibiotic prevention in gynecology. Concentrations of ceftizoxime in the serum, myometrium, endometrium and fallopian tubes]. / Antibiotikaprophylaxe in der Gynäkologie. Konzentrationen von Ceftizoxim in Serum, Myometrium, Endometrium und Tuben.

34 patients received an intravenous bolus injection of 2 g ceftizoxime over 5 min at various times before abdominal or vaginal hysterectomy. Ceftizoxime concentrations in myometrium were substantially higher than in salpinges and endometrium. Tissue concentrations of 4 micrograms/g could be maintained for at least 3 hours. The ceftizoxime tissue concentrations attained in myometrium, endometrium and salpinges justify therapeutic studies and controlled prospective clinical trials on the prevention of postoperative wound infections with this antibiotic.

[The effects of active and passive humidification on ventilation-associated nosocomial pneumonia]. / Einfluss von aktiver und passiver Befeuchtung auf die beatmungsassoziierte nosokomiale Pneumonie.

STUDY OBJECTIVE: Airway humidification of ventilated patients in an intensive care unit may be established by heated humidifying systems (active) or by the means of a (passive) heat and moisture exchange filter (HMEF). There is a controversial discussion about the influence of the type of humidification on the rate of ventilator-associated pneumonia (VAP). Among 3,585 patients both methods were tested over a period of 21 months in an open, non-randomized cohort study. The aim of the investigation was to compare the incidence of VAP caused by a change of humidification strategy. METHOD: All patients in a 16-bed surgical intensive care unit who required mechanical ventilation, were included. In the first period (period AB) 1,887 cases were handled with a heated humidifier. During the second period (period PB) 1,698 patients were treated using a HMEF. Infection control was established according to the national Infection Surveillance Program (KISS) based on the CDC criteria for VAP. RESULTS: During the period of 42 months, 99 cases of VAP were reported. The incidence for VAP was found to be 13.5 (AB) and 9.6 (PB) per 1,000 ventilator days, a rate of 32.3 and 22.4 VAP per 1,000 patients, respectively. The rate of VAP among the groups ( p=0.068) and the incidence of VAP per 1,000 ventilator days ( p=0.089) only just failed to reach a significant level, but in the group of patients requiring mechanical ventilation for more than 2 days, the difference did reach statistical significance ( p=0.012). CONCLUSION: Our results showed that the rate of VAP could be significantly reduced by changing the strategy from active to passive humidification devices, especially concerning patients requiring long-term respirator therapy. A more physiological humidification and a reduced number of airway manipulations are discussed as a possible explanation.

Netilmicin versus tobramycin in multi-centre studies.

In two prospective, randomized studies conducted in West Germany and involving 80 patients, netilmicin-ticarcillin was compared to tobramycin-ticarcillin in the treatment of serious systemic infections. Both regimens were essentially identical with respect to the clinical and bacteriological results they produced. The netilmicin group developed significantly less nephrotoxicity than the tobramycin group (0% versus 15%, P = 0.03). Ototoxicity also occurred less frequently in the netilmicin-treated patients (3% versus 10%, P = 0.4). In a large collaborative study involving 15 centres, 254 patients were enrolled. Clinical and bacteriological responses were excellent, with netilmicin and tobramycin equally effective, but the incidences of nephrotoxicity and ototoxicity were lower in patients treated with netilmicin than those receiving tobramycin.

[Antibacterial activity of clindamycin and lincomycin in broth, serum, and in combination with polymorphonuclear leukocytes against Staphylococcus aureus and Staphylococcus epidermidis]. / Antibakterielle Aktivität von Clindamycin und Linkomycin in Bouillon, Serum und in Kombination mit Polymorphkernigen Granulozyten gegen Staphylococcus aureus und Staphylococcus epidermidis.

We investigated the antibacterial activity of clindamycin and lincomycin at 1/4 X minimum inhibitory concentration (MIC), 1 X MIC and 4 X MIC against a serum-resistant Staphylococcus aureus and a serum-resistant Staphylococcus epidermidis strain in broth, in serum with and without the presence of leukocytes and in Hank's medium in combination with leukocytes alone. Against both test strains, lincomycin in broth and serum was similarly effective, whereas against S. aureus clindamycin in broth was somewhat more active. In the combined test mixture of serum with leukocytes, even a 1/4 X MIC of clindamycin or lincomycin markedly improved leukocyte killing of S. aureus, whereas both compounds could not further enhance the marked leukocyte killing of S. epidermidis, even at inhibitory concentrations. In Hank's medium with leukocytes alone, clindamycin and lincomycin had at the most only a bacteriostatic effect against both test strains.

Penetration of cefotetan into serum, myometrium, endometrium and salpinges.

24 patients received an intravenous 5-min bolus injection of 2 g cefotetan at various times prior to abdominal or vaginal hysterectomy. Cefotetan concentrations in salpinges were significantly higher than in myometrium and endometrium. Tissue concentrations of 16 micrograms/g could be attained for at least 5 h. At this concentration, 90% of most aerobic and anaerobic bacteria causing genital tract infections are inhibited.

In vitro combination effects of cefotetan with four aminoglycosides, piperacillin and mezlocillin on gram-positive and gram-negative nosocomial bacteria.

The in vitro efficacy of cefotetan in combination with gentamicin, tobramycin, amikacin, netilmicin against Staphylococcus aureus, Staphylococcus epidermidis and Enterobacter cloacae and with piperacillin and mezlocillin against Escherichia coli, Klebsiella pneumoniae, Serratia marcescens and Enterobacter cloacae was compared by use of the checkerboard agar dilution technique. On average, 60% of the gram-negative and 46% of the gram-positive strains were inhibited by additive, but only 22% of the gram-negative and 2% of the gram-positive bacteria were inhibited by synergistic cefotetan-aminoglycoside combinations. Netilmicin combinations were least active. On gram-negative bacteria, 63% of the cefotetan-penicillin combinations were additive and 11% synergistic. No antagonism occurred with any of the combinations.