Kinetics and maintenance of acquired resistance in mice to Listeria monocytogenes.

In the mouse system, acquired resistance to Listeria monocytogenes can only be demonstrated after immunization with viable microorganisms. A successful state of immunity cannot be elicited with formalin-killed organisms or bacterial cell-derived products. Viable, serologically cross-reactive organisms (not mouse pathogenic) do not induce a state of immunity as measured by acquired resistance. The duration of immunity, once established, is dose independent, and the absolute interval of its existence is not extended by secondary challenge with large numbers of viable organisms. The decline of immunity in actively immunized animals is not altered by antigenic challenge with formalin-killed cells or cell products. This indicates that the cellular requirements for the development of host resistance are similar for induction as well as maintenance. In vitro measurements of cellular immunity by migration inhibition indicate that formalin-killed organisms as well as cell products were recognized by actively sensitized lymphocytes obtained from immune animals.     

Short- and long-term results of liver transplantation in infants aged less than 6 months

BACKGROUND: Despite major surgical and medical advances, it is still a challenge to perform transplantation in small infants. This study, focusing on short- and long-term outcomes, summarizes our 10-year experience with liver transplantation (LTx) in infants aged less than 6 months. PATIENTS AND METHODS: We analyzed 43 patients aged 6 months or less (range: 12-184 days, median: 136 days) whose median weight at the time of LTx was 5.8 kg (range: 2.8-8.0 kg). The reasons for LTx were biliary atresia (n=27; 62.8%), neonatal hepatitis (n=6; 14%), neonatal cholestasis (n=4; 9.3%), and miscellaneous (n=6; 14%). The patients were followed up for a median time of 3 years and evaluated with respect to graft function, physical, and neurodevelopmental outcome. RESULTS: The patient survival was 90.7% after 1 year and 87.2% after 2 years. The graft survival was 86% after 1 year and 82.1% after 2 years. Twelve patients (27.9%) experienced 15 surgical complications requiring intervention, two of whom demonstrated vascular thrombosis (4.7%). Acute early rejection occurred in 15 patients (34.9%), and chronic rejection occurred in 3 patients (7%); 83.3% of the patients had normal liver function test results at the time of evaluation. Complications such as posttransplant lymphoproliferative disease (4.7%) and persistent arterial hypertension (4.7%) were rarely seen. The physical and neurodevelopmental outcomes were good. CONCLUSIONS: LTx in infants aged less than 6 months provides excellent short- and long-term results. Low weight or young age of infants awaiting LTx should not be exclusion criteria for LTx.     

DRG based development of revenues in orthopaedic surgery. A comparison on the development of cost weights and average lengths of hospital stay in Germany (G-DRG V1.0) and in Australian teaching hospitals (AR-DRG 4.1)

STUDY GOAL: In September 2002 the Federal Ministry of Health (BMG) has passed a decree in respect to the diagnosis related group system (G-DRG) for German hospitals (KFPV). From 2003 on the basis of this decree German hospitals were offered for the first time to use the G-DRG system optionally according to the " Section 17b Abs.4 of the Hospital Financing Law (Krankenhausfinanzierungsgesetz-KHG)". In addition the preliminary calculation data for the German DRG-System were published. The goal of this study was to compare the development of the cost weights and the average lengths of hospital stay in Australian teaching hospitals between 1998 and 2001 with the cost weights and average lengths of hospital stay in German hospitals according to the data published in the first German calculation (G-DRG V1.0). METHODS: An analysis was performed using the publically accessible reports on the national hospital cost data collections from 1998 until 2001 as they were published by the Commonwealth Department of Health and Aged Care in Australia. These data were compared with the cost weight calculation and average lengths of hospital stay calculation of the Institute for the Assessment of Cost Weights (InEK GmbH) published in the G-DRG V1.0 version. RESULTS: From 1998 until 2001 the cost weights of medical procedures such as spine fusion operations and joint arthroplasty revision operations on the hip and on the knee with severe complications and co-morbidities increased continuously. This development was not seen in DRG's without complications and co-morbidities, in food and ankle procedures and in shoulder procedures. The average length of hospital stay decreased continuously with very few exceptions. The average length of stay for so called C-DRG's (I09, I12, I13, I68, I69, I71, I75, I76) and in particular so called Z-DRG's (I16-I27) are in general longer by a factor of at least 2 in German hospitals when compared to Australian hospitals. CONCLUSION: A high quality of right-coding of ICD and ICPM Codes is a prerequisite to reach the correct revenue-relevant DRG. In Germany the average length of hospital stay is significantly longer than in Australia. In general the MDC-8-DRG's have demonstrated a smaller range when compared with the first calculated German DRG's in respect to the complexity of the procedures. Future management of the expected reductions in hospital stay will be based on a continuous co-operative efforts to improve the structural-, process- and (clinical guidelines and clinical pathways) and outcome quality of our medical procedures. The central objective of this effort is the well-being of our patients.     

Prospective validation of computed tomographic screening of the thoracolumbar spine in trauma

OBJECTIVE: Concern for thoracolumbar spine (TLS) injuries after major trauma mandates immobilization pending radiographic evaluation. Current protocols use standard posteroanterior and lateral radiographs of the thoracolumbar spine (XR/TLS), but many patients also undergo abdominal or thoracic computed tomographic (CT) scanning. We sought to evaluate whether helical truncal CT scanning performed to evaluate visceral trauma images the spine as well as dedicated XR/TLS. METHODS: We prospectively studied 222 consecutive patients sustaining high-risk trauma requiring TLS screening because of clinical findings or altered mentation. The chest, abdomen, and pelvis were imaged with one intravenous contrast infusion. All patients had CT scan of the chest, abdomen, and pelvis (CT/CAP) and XR/TLS. Initial radiologic diagnoses were compared with the discharge diagnosis of acute fractures confirmed by thin-cut CT scan and/or clinical examination of the patient when alert. RESULTS: Of 222 patients studied, 215 were fully evaluated. Thirty-six (17%) had acute TLS fractures. The accuracy of CT/CAP for TLS fractures was 99% (95% confidence interval [CI], 96-100%). The accuracy of XR/TLS was 87% (95% CI, 82-92%). Sensitivity, specificity, and positive and negative predictive values were better for CT/CAP than for XR/TLS. CT/CAP found acute fractures XR/TLS missed, and correctly classified old fractures XR/TLS read as "possibly" acute. The total XR/TLS misclassification rate was 12.6% (95% CI, 8.4-19%); for CT/CAP it was 1.4% (95% CI, 0.3-3.3%). No fractures were missed by CT/CAP. No unstable fracture was missed by either technique. CONCLUSION: CT/CAP diagnoses TLS fractures more accurately than XR/TLS. Neither misses unstable fractures, but CT scanning finds small fractures that benefit by treatment and identifies chronic disease better. CT screening is far faster and shortens time to removal of spine precautions. CT scan-based diagnosis does not result in greater radiation exposure and improves resource use. Screening the TLS on truncal helical CT scanning performed for the evaluation of visceral injuries is more accurate than TLS imaging by standard radiography. CT/CAP should replace plain radiographs in high-risk trauma patients who require screening.     

Periodontal bacteria in adult twins

BACKGROUND: Both environmental and genetic factors are known to influence clinical measures of periodontal disease. The purpose of this study was to determine whether genetic factors similarly influence the presence of specific periodontal bacteria in subgingival plaque. METHODS: Reared-together and reared-apart monozygous (MZ) and dizygous (DZ) adult twins were examined clinically. Demographic and behavioral information was obtained from each subject by questionnaire. Subgingival plaque samples were obtained from the index teeth, and the presence of P. intermedia, P. gingivalis, A. actinomycetemcomitans, E. corrodens, and F. nucleatum was determined using an immunoassay. RESULTS: Microbiological and clinical data were available for 169 twin pairs. The subject-based prevalences of the bacteria in the twin groups ranged from 11% for Porphyromonas gingivalis to 40% for F. nucleatum. For all species examined, the concordance rates were not significantly different (P > 0.05) between MZ and DZ twin groups. These findings were apparent despite similar smoking histories, self-reported oral hygiene practices, and antibiotic use in the twin groups. Furthermore, MZ twins reared together were not more similar than MZ reared-apart twins with respect to any bacterial species examined. CONCLUSIONS: These findings suggest that in a population with access to routine dental care, any effects that host genes and the early family environment have on the presence of specific bacteria in subgingival plaque are not apparent in adulthood. Most twins with disease in this study had early periodontitis. Results from this study may not necessarily be extrapolated to more advanced disease states.