Fritz Stauffer

Snapshot of Moving and Expanding Clones of Mycobacterium tuberculosis and Their Global Distribution Assessed by Spoligotyping in an International Study

ABSTRACT The present update on the global distribution of Mycobacterium tuberculosis complex spoligotypes provides both the octal and binary descriptions of the spoligotypes for M. tuberculosis complex, including Mycobacterium bovis, from >90 countries (13,008 patterns grouped into 813 shared types containing 11,708 isolates and 1,300 orphan patterns). A number of potential indices were developed to summarize the information on the biogeographical specificity of a given shared type, as well as its geographical spreading (matching code and spreading index, respectively). To facilitate the analysis of hundreds of spoligotypes each made up of a binary succession of 43 bits of information, a number of major and minor visual rules were also defined. A total of six major rules (A to F) with the precise description of the extra missing spacers (minor rules) were used to define 36 major clades (or families) of M. tuberculosis. Some major clades identified were the East African-Indian (EAI) clade, the Beijing clade, the Haarlem clade, the Latin American and Mediterranean (LAM) clade, the Central Asian (CAS) clade, a European clade of IS6110 low banders (X; highly prevalent in the United States and United Kingdom), and a widespread yet poorly defined clade (T). When the visual rules defined above were used for an automated labeling of the 813 shared types to define nine superfamilies of strains (Mycobacterium africanum, Beijing, M. bovis, EAI, CAS, T, Haarlem, X, and LAM), 96.9% of the shared types received a label, showing the potential for automated labeling of M. tuberculosis families in well-defined phylogeographical families. Intercontinental matches of shared types among eight continents and subcontinents (Africa, North America, Central America, South America, Europe, the Middle East and Central Asia, and the Far East) are analyzed and discussed.

Global Distribution of Mycobacterium tuberculosis Spoligotypes

We present a short summary of recent observations on the global distribution of the major clades of the Mycobacterium tuberculosis complex, the causative agent of tuberculosis. This global distribution was defined by data-mining of an international spoligotyping database, SpolDB3. This database contains 11,708 patterns from as many clinical isolates originating from more than 90 countries. The 11,708 spoligotypes were clustered into 813 shared types. A total of 1,300 orphan patterns (clinical isolates showing a unique spoligotype) were also detected.

Release of TNF alpha and IL6 from human monocytes infected with Mycobacterium kansasii: a comparison to Mycobacterium avium.

SummaryTumor necrosis factor α (TNFα) and interleukin 6 (IL6) are cytokines with a varied spectrum of inflammatory and immunological activities, for example modulation of acute phase proteins, fever and stimulation of B-lymphocytes.Mycobacterium avium has been shown to stimulate the release of TNFα and IL6 from cultured human monocytes and macrophages into the cell supernatant. Cultured human monocytes were infected withMycobacterium kansasii andM. avium. The concentrations of TNFα and IL6 were measured in the supernatant. Monocytes infected withM. kansasii produced significantly lower amounts of TNFα (34.8±20.3 pg/ml) and IL6 (12.0±8.9 pg/ml) compared to monocytes infected withM. avium (198.3±171.7 pg/ml and 63.2±37.6 pg/ml respectively). The extent of cytokine production might be relevant for the clinical manifestation of mycobacterial disease.ZusammenfassungTumor-Nekrose-Faktor α (TNFα) und Interleukin 6 (IL6) sind Zytokine mit einem breiten Spektrum an inflammatorischen und immunologischen Aktivitäten wie beispielsweise Modulation der Akutphase-Proteine, Fieber und Stimulation der B-Lymphozyten. Es konnte gezeigt werden, daßMycobacterium avium den Ausstoß von TNFα und IL6 aus humanen Monozyten/Makrophagenkulturen in den Zellüberstand stimuliert. Humane Monozytenkulturen wurden mitMycobacterium kansasii undM. avium infiziert. In den Zellüberständen wurden die Konzentrationen an TNFα und IL6 gemessen. Die mitM. kansasii infizierten Monozytenkulturen produzierten signifikant weniger TNFα (34,8±20,3 pg/ml) und IL6 (12,0±8,9 pg/ml) verglichen mit jenen infiziert mitM. avium (198,3±171,7 pg/ml beziehungsweise 63,2±37,6 pg/ml). Das Ausmaß der Zytokinproduktion könnte für das klinische Bild mykobakterieller Infektionen von Bedeutung sein.

Reprocessing of dental instruments in washer-disinfectors: does a representative test soil exist in dentistry?

Background: Reprocessing of medical devices, being classified as semi-critical B is recommended to be performed in a washer-disinfector. In order to estimate, whether the expected contaminants of the various medical disciplines can be effectively removed by this washer-disinfector, different so called “test soils” have been proposed to be tested as a marker of cleaning efficacy of the disinfector. Todays described test soils are optimised for the testing of contaminations occurring in surgical procedures, but not for dental procedures. Methods: In this study the test soils being proposed in the EN 15883-5 (e.g. KMNE soil, recipe by Koller and coagulated sheep’s blood) were compared with 8 reference substances used in the conservative-prosthetic dental practice. The success of the cleaning efficacy in the washer-disinfector was checked visually and by determining the residual protein concentration on the contaminated instruments after the cleaning procedure. Results: It could be shown that in contrast to the proposed test soils of the EN 15883-5, the used reference substances of the dental practice could not be removed by the washer-disinfector. Removal of these reference substances was only possible after manual or ultrasonic cleaning. Conclusions: Since blood plays a subordinate role as a contaminant of instruments during conservative-prosthetic dental treatments, testing of the cleaning efficacy of the washer-disinfector with test soils according to the proposals of the EN 15883-5 is not representative in this discipline of dentistry. Most of the materials used in dental practice can only be removed manually or with the help of the ultrasound bath.

Infant Tuberculosis in Austria- Trend Reversal since 1990?

SummarySince 1990 a relatively high number of cases of childhood tuberculosis has been observed in Austria, mainly occurring in the age-group of 0–4 years. Within this group most cases were registered in 1995. Since the beginning of 1995 the establishment of a lab-supported nationwide data collection system enables a more detailed recording of the cases diagnosed. Out of the 85 cases with infant tuberculosis registered in 1995 and 1996, 66 were diagnosed with pulmonary manifestation. In 45 cases tuberculosis was proven by culture. In nine (20%) of these cases the most likely route of infection has appeared to be direct transmission from an adult in the same household suffering from culture proven tuberculosis in the same year. For three of the cases the DNA of the isolatedMycobacterium tuberculosis strains from the adult and the infant was typed using RFLP analysis. In each case identical strains could be demonstrated.

Testing for aerobic heterotrophic bacteria allows no prediction of contamination with potentially pathogenic bacteria in the output water of dental chair units

Background: Currently, to our knowledge, quality of output water of dental chair units is not covered by specific regulations in the European Union, and national recommendations are heterogeneous. In Germany, water used in dental chair units must follow drinking water quality. In the United States of America, testing for aerobic heterotrophic bacteria is recommended. The present study was performed to evaluate whether the counts of aerobic heterotrophic bacteria correlate with the presence of potentially pathogenic bacteria such as Legionella spp. or Pseudomonas aeruginosa. Methods: 71 samples were collected from 26 dental chair units with integrated disinfection device and 31 samples from 15 outlets of the water distribution pipework within the department were examined. Samples were tested for aerobic heterotrophic bacteria at 35°C and 22°C using different culture media and for Legionella spp. and for Pseudomonas aeruginosa. Additionally, strains of Legionella pneumophila serogroup 1 were typed with monoclonal antibodies and representative samples of Legionella pneumophila serogroup 1 were typed by sequence based typing. Results: Our results showed a correlation between different agars for aerobic heterotrophic bacteria but no correlation for the count of aerobic heterotrophic bacteria and the presence of Legionella spp. or Pseudomonas aeruginosa. Conclusion: Testing for aerobic heterotrophic bacteria in output water or water distribution pipework within the departments alone is without any value for predicting whether the water is contaminated with potentially pathogenic bacteria like Legionella spp. or Pseudomonas aeruginosa.

Induction of the Release of Prostaglandin E2 from Polymorphonuclear Neutrophil Granulocytes by Bacteroides fragilis: Its Possible Role in the Pathogenesis of Mixed Infections

The presence of anaerobic bacteria, especially of Bacteroides (B.) fragilis, in abdominal abscesses, infected decubitus ulcera, and the infected foot of diabetic patients is well documented. The importance, however, of these microorganisms in the pathogenesis of deep tissue infections has still to be evaluated. Therefore, the aim of this study was to evaluate the potency of B. fragilis as compared to aerobic bacteria widely known for causing inflammation, in inducing the release of prostaglandin E2 from polymorphonuclear granulocytes. Prostaglandin E2 is a potent vasodilator and contributes to edema and erythema, which are part of the inflammatory response. Furthermore, the cAMP-content of the neutrophils was determined after stimulation of the cells with the various bacteria. Of the bacterial species tested, B. fragilis proved to be one of the most potent triggers for prostaglandin E2 release from neutrophils indicating a possible major role of this microorganism in the pathogenesis of mixed infections.