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Microbiological diagnostic procedures have changed rapidly in recent years. This is especially true in the field of molecular diagnostics. Classical culture-based techniques are still the gold standard in many areas; however, they are already complemented by automated and also molecular techniques to guarantee faster and better quality results. The most commonly used techniques include real-time polymerase chain reaction (RT-PCR) based systems and nucleic acid hybridization. These procedures are used most powerfully from direct patient samples or in assays to detect the presence of nonculturable or fastidious organisms. Further techniques such as DNA sequencing are not yet used routinely for urological samples and can be considered experimental. However, in conjunction with dropping prices and further technical developments, these techniques promise to be used much more in the near future. Regarding bacterial identification from culture, mass spectrometry (MALDI-TOF MS) has become the technique of choice in recent years especially in Europe. It has tremendously shortened the time to result. This is now going to be extended to antibiotic susceptibility testing. This is of paramount importance in view of ever rising antimicrobial resistance rates. Techniques described in this review offer a faster and better microbiological diagnosis. Such continuous improvements are critical especially in times of cost pressure and rising antimicrobial resistance rates. It is in our interest to provide the best possible care for patients and in this regard a good and effective communication between the laboratory and the clinician is of vital importance.

In Europe, besides the threat of terrorist attacks involving conventional methods such as explosive devices and automatic weapons, there is also a potential threat of terrorist groups using non-conventional material like biological agents in the scope of future attacks. Consequently, rapid and reliable detection systems for biological agents are being developed and tested continuously to inform crisis management. For environmental detection, a broad spectrum of different laboratory-based techniques has been developed for relevant biological agents. However for environmental samples, fast and reliable on-site detection methods are desired by first responders for rapid assessment.Based on different functional principles, generic, immunological and nucleic-acid-based on-site detection methods can be distinguished. Those should be facile, fast, sensitive, and specific. However, commercially available kits usually have limited sensitivity and often have not been validated independently. Furthermore in this context, the multitude of relevant biological agents that potentially have to be considered present in complex environmental matrices poses a serious challenge for reliable detection. Therefore, detailed knowledge of the specific scope of applications and the limitations of different analytical systems is necessary to evaluate the results obtained purposefully.The aim of this article is to provide an overview of the analytical principles, benefits and limitations of prevailing on-site environmental detection systems for bioterrorism-relevant viruses, bacteria and toxins. Despite promising developments the informative value of currently available on-site tests is still limited. Thus, expert laboratories have to conduct confirmatory testing.

Diagnosis of tuberculosis (TB) is difficult, since symptoms are often very unspecific or lacking. However active, prompt and accurate diagnosis is the key element in the public health response to tuberculosis and the cornerstone of tuberculosis control. Different diagnostic methods for an assured diagnosis of TB are necessary. Chest radiography is a useful keystone to identify tuberculosis, but diagnosis of tuberculosis cannot be established by radiography alone. CT scanning is used in patients without pathological chest radiography but clinically suspected active TB and to differentiate TB from other diseases. Radiological appearance is primarily determined by the immune status of patients and caverns and disseminated disease foci are often observed. Laboratory diagnostic methods include microscopic identification of acid-fast mycobacteria from any body fluid (especially sputum), as well as isolation and characterisation of mycobacteria in culture. It is then possible to type the pathogens by the shape of their colony, their growth behavior and their biochemical characteristics. These methods are regarded as the gold standard in diagnosis of active TB. In patients who are highly suspected of having TB, but whose sputum specimens tested negative for mycobacteria, a nucleic acid amplification test is additionally performed. Moreover, sensitivity testing with first and second line antitubercular drugs is applied as standard. Laboratory diagnostic testing of cellular immunity against pathogenic mycobacteria employs the tuberculin skin test (TST, Mantoux tuberculin test) or the more specific interferon γ test to determine γ interferon released by T lymphocytes stimulated in vitro. The new ELISA and ELISPOT procedures exhibit higher test specificity and less cross reactivity to NTM (non-tuberculosis mycobacteria), are independent of BCG-vaccination status and correlate better with the degree of exposure than does the TST.

Endoprosthetic joint replacement is one of the most common and most successful operations in current medicine. With the increase in joint prosthesis implantations, the number of periprosthetic infections is also rising. Detection of the causative pathogen and its antimicrobial susceptibility is crucial for successful antibiotic therapy. For a reliable diagnosis, in addition to conventional microbiological methods (synovial fluid culture and intraoperative periprosthetic tissue samples), other methods of detecting biofilms are used. With sonication of the removed implant components, microorganisms are released from the implant surface and then detected qualitatively and quantitatively in the sonication fluid. The sonication is particularly useful for chronic, "low-grade" infections in which a small number of bacteria are present and the biofilm adheres more strongly to the prosthesis surface. The sonication fluid is suitable for aerobic and anaerobic cultures, in addition to newer, culture-independent detection methods (e.g., molecular methods, mass spectrometry, microcalorimetry). In the article the significance, advantages and disadvantages, and the practical implementation of the sonication of implants are presented and critically discussed.

Multiplex PCR technologies progressively find their way in clinical microbiology. This technique allows the simultaneous amplification of multiple DNA targets in a single test run for the identification of pathogens up to the species level. Various pathogens of infectious diseases can be detected by a symptom-oriented approach clearly and quickly with high reliability. Essentially multiplex PCR panels are available for clarification of gastrointestinal, respiratory, sexually transmitted infections and meningitis. Today's offer from industry, university hospitals and large private laboratories of Switzerland is tabulated and commented.Die Multiplex PCR Technologie hält in der mikrobiologischen Diagnostik mehr und mehr Einzug. Diese Technik erlaubt in einem einzigen Probenlauf die simultane Amplifikation von mehreren DNA/RNA-Zielsequenzen von Erregern über die Speziesebene hinaus. Verschiedene Erreger von Infektionskrankheiten können durch einen Symptom-orientierten Approach eindeutig und rasch mit hoher Zuverlässigkeit nachgewiesen werden. Im Wesentlichen verfügt man heute über Multiplex PCR-Panels zur Abklärung von gastrointestinalen, respiratorischen, urogenitalen Infekten, sowie zur Meningitis-Diagnostik. Das heutige Angebot der Industrie, der Universitätsspitäler und der größeren Privatlabors der Schweiz wird tabellarisch dargestellt und kommentiert.

Pneumococci remain the most important cause for community-acquired pneumonia. The colonization of the nasopharynx is prerequisite for their transmission and the colonization of toddlers are an important reservoir also for infections in the elderly. Since pneumococcal conjugate vaccines reduce the colonization rate of children its widespread use has also resulted in a reduction of invasive pneumococcal disease in adults. Advanced age and comorbidity are the most important risk factors for pneumococcal pneumonia and the mortality in this risk group is still very high. The strongest risk factor for invasive pneumococcal infections, however, is HIV/AIDS and solid or hematologic malignancies. A more rapid identification could aid de-escalation of empiric antibiotic therapy. The pneumococcal urinary antigen test, however lacks sensitivity for this purpose. In contrast, the direct identification of pathogens from positive blood culture bottles by MALDI-TOF is a very encouraging development in diagnostic microbiology. In several cohort studies patients treated with a combination of a betalactam plus macrolide had a lower mortality than patients treated with betalactam monotherapy. If these observations reflect a truly beneficial effect of combination therapy or rather confounding of the studies remains unclear and evidence from interventional studies is needed.

Zusammenfassung Infektiöse Lungenerkrankungen oder Pneumonien sind die Haupttodesursache innerhalb der Infektionskrankheiten in Deutschland. Hierbei ist die bakterielle Verursachung am häufigsten. Die Form der Entzündung wird meist durch das schädigende Agens bestimmt, jedoch sind häufig verschiedene Reaktionen anzutreffen. Morphologisch kann nur in wenigen Fällen der Erreger konkret bestimmt werden, sodass meist eine zusätzliche mikrobiologische Erregerdiagnostik notwendig ist. Klinisch erfolgt eine Einteilung in ambulant erworbene und nosokomiale Pneumonien, Pneumonien bei Immunsuppression und die Mykobakteriosen. Histologisch ist eine Einteilung gemäß der bevorzugten Ausbreitung in alveoläre und interstitielle bzw. in lobäre und herdförmige Pneumonien möglich.

In this chapter we will give an overview over the most frequent etiologies of fever in infants in Switzerland, propose an algorithm to evaluate this children, and we will end up with a discussion on the value of additional laboratory parameters. Fever in infants and small children is a leading cause for parents to seek medical attention. The vast majority has a self limiting viral infection, but all the same, all infants need to be thoroughly evaluated. After this process, the treating physician has to decide, which child needs to be specifically treated or cared for, either to avoid overtreatment nor overlooking a serious infection. Because of a broader immunization coverage against bacterial infections, the epidemiology of invasive bacterial disease is changing. Additional laboratory work up is sometimes necessary, but has it's limitations. The interpretation of lab values must taken into account the changing prevalence of serious bacterial infections. Newer parameters (e. g. Procalcitonin) are upcoming, of which the importance is still debatable. Fever causes in this age other than infectious diseases will be alluded.Fieber ohne Fokus ist beim febrilen Kleinkind (1 – 36 Monate alt) eine häufige klinische Situation. Aus dieser Gruppe dasjenige Kind zu identifizieren, das eine bakterielle Infektion als Ursache hat und eine entsprechende Abklärung und Therapie braucht, ist anspruchsvoll. Die Einführung der Impfung für Säuglinge gegen Pneumokokken und Meningokokken Gruppe C hat in den letzten Jahren zu relevanten Veränderungen der Epidemiologie geführt, das Risiko einer invasiven Infektion hat deutlich abgenommen. Die häufigste bakterielle Infektion ist bei einem immunisierten Kind die Harnwegsinfektion. Die Wertigkeit von zusätzlichen Laboruntersuchungen, die unter anderem beeinflusst wird durch die Vortestwahrscheinlichkeit, ist neu zu beurteilen. Unter den nun gegebenen Umständen können Anpassungen und damit eine Vereinfachung im Management dieser Kinder vorgenommen werden. Diese Punkte sollen unter anderem im folgenden Artikel ausführlicher besprochen werden.

After the International Health Regulations of 2005, 194 states agreed to minimal standards to assure health; accordingly, the obligation for safeguarding appropriate laboratory diagnostic capacities has existed under international law since 15 June 2007. Basically, developing and optimizing faster and more innovative testing methods should be the main aim of public health reference laboratories in order to guarantee optimal outbreak detection, control measures, and patient management. All these measures can only be successfully implemented if microbiological primary diagnostics remain comprehensive and do not fall victim to apparent budgetary restrictions. Effective microbiological diagnostics not only help the patient who is directly affected, but also have an effect on the efforts of public health services in controlling infectious disease. In this respect, microbiological routine diagnostics differ substantially from medical-chemical laboratory diagnostics.

Nosocomial pneumonia (HAP) is a frequent complication of hospital care. Most data are available on ventilator-associated pneumonia. However infections on general wards are also increasing. A central issue are infections with multi drug resistant (MDR) pathogens which are difficult to treat particularly in the empirical setting potentially leading to inappropriate use of antimicrobial therapy. This guideline was compiled by an interdisciplinary group on the basis of a systematic literature review. Recommendations are made according to GRADE giving guidance for the diagnosis and therapy of HAP on the basis of quality of evidence and benefit/risk ratio. The guideline has two parts. First an update on epidemiology, spectrum of pathogens and antiinfectives is provided. In the second part recommendations for the management of diagnosis and treatment are given. Proper microbiologic work up is emphasized for knowledge of the local patterns of microbiology and drug susceptibility. Moreover this is the optimal basis for deescalation in the individual patient. The intensity of antimicrobial therapy is guided by the risk of infections with MDR. Structured deescalation concepts and strict limitation of treatment duration should lead to reduced selection pressure.

Applying diagnostic techniques in palliative care (PC) requires a thorough balance between a physical, psychosocial (and financial) burden and its therapeutic relevance in far advanced diseases. The extent of diagnostic employment in PC, preferred techniques, application problems, its informative value and therapeutic significance still have to be described.The Hospice and Palliative Care Evaluation (HOPE) 2007 collected data from the application of microbiological and imaging techniques in German PC institutions. Furthermore, 70 consecutive ultrasound scans in our PC unit have been retrospectively analyzed.In 691 PC patients (from a total of 3184 in HOPE), diagnostic techniques (DIA) were applied and documented.In-patients with DIA (86,1 %) and the HOPE collective showed a comparable age and duration of hospital stay. Microbiological techniques contributed to 26,1 % of all documented in-patient investigations, imaging techniques 69,1 %. Ultrasound was the preferred imaging technique on PC units (67,1 %), whilst radiography, CT or MRI scans were rather employed on oncology wards. Nuclear imaging was rarely documented. In 80,8 %, imaging diagnostics were considered relevant for further treatment decisions (in-patients only); transportation problems and pain during imaging were relevant obstacles. In our own patient cohort, ultrasound was applied rather for general prognostic purposes, less often resulting in immediate therapeutic actions. Transportation problems could be almost entirely avoided by using a mobile ultrasound device.DIA in PC are applied independently of age or duration of hospital stay; its therapeutic significance is considered to be high; procedural problems may be resolvable. Therefore, this survey might challenge the tradition of low technology in PC.

It is well known that the early initiation of a specific antiinfective therapy is crucial to reduce the mortality in severe infection. Procedures culturing pathogens are the diagnostic gold standard in such diseases. However, these methods yield results earliest between 24 to 48 hours. Therefore, severe infections such as sepsis need to be treated with an empirical antimicrobial therapy, which is ineffective in an unknown fraction of these patients. Today's microbiological point of care tests are pathogen specific and therefore not appropriate for an infection with a variety of possible pathogens. Molecular nucleic acid diagnostics such as polymerase chain reaction (PCR) allow the identification of pathogens and resistances. These methods are used routinely to speed up the analysis of positive blood cultures. The newest PCR based system allows the identification of the 25 most frequent sepsis pathogens by PCR in parallel without previous culture in less than 6 hours. Thereby, these systems might shorten the time of possibly insufficient antiinfective therapy. However, these extensive tools are not suitable as point of care diagnostics. Miniaturization and automating of the nucleic acid based method is pending, as well as an increase of detectable pathogens and resistance genes by these methods. It is assumed that molecular PCR techniques will have an increasing impact on microbiological diagnostics in the future.

For the vocal rehabilitation of laryngectomized patients, voice prostheses are actually one of the best known methods. Caused by the surface colonisation with bacteria and fungi the life time of the prostheses is limited to 3-4 months.In a time period of 127 months we analysed the surface colonisation of 118 voice prostheses.The mean life time of the prostheses was 156 days. In reference to the prosthesis model we also recorded different times of usage (ESKA-Herrmann 141, Provox 2 184 and Provox 1 204 days (p0.05)). In the microbiological examination the dominating bacteria were S. aureus, Klebsiella sp. and Proteus sp. It was possible to cultivate all these bacteria on every type of prosthesis used in the study. In addition C. albicans, C. glabrata, C. krusei and C. tropicalis were the main fungi on the silicone surface. Thereby a more frequent colonisation with C. krusei on ESKA-Herrmann prostheses was measured, caused by the bigger contact area with saliva on this model (p=0.034).Because of the similar position and way of function, all types of voice prostheses are colonized by almost the same species of bacteria and fungi. But in dependency of the type an affinity of individual species to special prostheses exist. The knowledge of these individual affinities is necessary for the further development of voice prostheses. Furthermore the diversity of bacteria and fungi species showed a level of saturation on the surface. This is caused by the limited space on the silicone prostheses.

Vasculitis and vasculopathies of the central and peripheral nervous system can be caused by infectious diseases. Vasculitis can lead to stenosis, occlusion and aneurysm formation of blood vessels which may result in stroke or cerebral haemorrhage. In cases of peripheral nervous system involvement mononeuritis multiplex and symmetric peripheral neuropathy are possible. The diagnosis is based on clinical presentation, serology, cerebrospinal fluid analysis and neuroradiologic examinations. In cases of peripheral neuropathy neurophysiologic examinations and biopsy of the sural nerve can lead to the diagnosis. A fast and efficient antimicrobial therapy is the most important treatment option. In cases of peripheral neuropathies short-term treatment with corticosteroids and plasma exchange may be helpful.

The frequency and range of bacterial pathogens in respiratory tract infections depends on a variety of variables. The aetiology is influenced by the type of respiratory tract infection (acute bronchitis, acute exacerbation of chronic bronchitis, community-acquired pneumonia, nosocomial pneumonia), geographic and seasonal factors, and by the diagnostic methods implemented to identify the pathogens. Furthermore, there exists a considerable uncertainty concerning the clinical relevance of positive bacteriological findings in respiratory secretions because they are retrieved from non-sterile or contaminated environments. To differentiate infection from contamination, both microbiological and clinical findings have to be assessed, which might be difficult in the setting of systemic or local immunosuppression.

There are 12 dermatologically relevant Microsporum (M.) species. The most frequent species are M. canis, M. audouinii and M. gypseum. We report an infection of the right forearm with the rare dermatophyte M. fulvum. A KOH examination of scales revealed a tinea corporis. The scales were cultured on Dermasel(R) agar with the identification of the geophilic dermatophyte M. gypseum. However, ITS sequencing and mass spectrometry revealed M. fulvum as the correct pathogen.

Taxonomy is an artificial system to classify living organisms. For this purpose, different concepts of how to define a species can be used. In recent years, DNA analysis has especially helped to better understand the phylogenetic relations of dermatophytes and thus influenced the distinction of dermatophyte species. In some cases species previously considered separate were made synonymous. It may be necessary to discriminate different varieties within a particular species if this is required by their typical morphologic, physiologic or epidemiological characteristics. Trichophyton eboreum with its perfect state Arthroderma olidum was recently described as a new species. The taxonomic order of dermatophytes must continuously be updated by integrating new findings; at the same time, meaningful and proven criteria should be retained.

In a secondary care hospital in Germany with an in-house microbiology laboratory, an 84-year-old female patient with candidemia was selected for determination of the time periods required for each diagnostic step preceding the application of the first dose of antimycotic treatment. The total time from the beginning of fever to the first dose of fluconazole was 25 hours and 10 minutes. The largest delay occurred between the positive signal of the blood culture bottle during the night and the start of the work-up of the positive blood culture bottle in the morning. Improvements appear to be possible in both clinical and laboratory settings by optimizing pre-analytical, analytical, and post-analytical procedures.

Infectious endophthalmitis is a serious complication of intraocular surgery, perforating injury, or septic dissemination. Detection of the causative microorganisms is essential for effective treatment. Published positive culture rates vary from 24 to 95 %. To achieve a high positive rate of detection of microorganisms all material necessary to set up a culture has to be available in the operation theatre. Important is a variety of appropriate culture media: we use Columbia, Hematin, ENDO and yeast-cysteine blood plates as well as a nutrient solution. Samples may be brought into the culture media directly within the operation theatre. If no immediate transport to a specialised laboratory is possible, media may be cultured in the eye hospital under optimal conditions. Concurrently, undiluted samples should be used for eubacterial PCR. While standard PCR can only detect the causative microorganism, standard culture procedures provide additional information regarding resistance to anti-microbiologic therapies. In the case of presumed fungal endophthalmitis the collected vitrectomy fluid has to be centrifuged and thereafter cultured. In presumed endogenous endophthalmitis also extraocular samples should be examined (e. g., blood culture and smears from other sites of infection). With this approach a high detection rate can be achieved in patients with endophthalmitis.

Recent developments in diagnostic molecular biology allow novel approaches in the detection of infections in ocular fluids. In endophthalmitis new PCR techniques often allow faster microbiological diagnosis than conventional culture methods. Furthermore they show a higher sensitivity and can also be applied after pre-treatment with antibiotics where culture techniques often fail. Molecular techniques are of particular use in recurrent and therapy-resistant infections. In the diagnostics of uveitis molecular approaches enable the detection of fastidious microbes and of pathogens that cannot be found by culture methods. In special situations identification even to the species level is possible. In immunocompromised patients molecular techniques show more accurate results than serological ones. However, molecular diagnostic tools also bear limitations that have to be considered.

The European Directive 98/79/EC on in-vitro diagnostic medical devices (IVD) stipulates the marketing and post marketing surveillance of IVD in the European Economic Area. In cases of incidents and field corrective actions related to IVD, manufacturers have to inform the responsible Competent Authorities. In Germany, the Federal Institute for Drugs and Medical Devices (BfArM) is the responsible Competent Authority for most IVD. Only a small subset of IVD for immune hematological and infectiological testing, as well as tissue typing specified in Annex II of the Directive, is under the responsibility of the Paul-Ehrlich-Institute (PEI). Until the end of 2005 the BfArM received a total of 653 notifications regarding IVD. From these 48 related to IVD used for diagnostics in transfusion medicine and tissue typing which are subject of this study. The investigated products included reagents (tests, calibrators and controls) used for immune hematological analysis as far as they are not under the responsibility of the PEI, analyzing instruments used for immune hematological testing, liquid handling systems for sample preparation and a small subset of analysing instruments and reagents for tissue typing. Most of the reports originated from manufacturers (n=27, 56.3%) and Competent Authorities (n=20; 41.7%) whereas other sources played only minor roles. Product failures were confirmed by the investigations of the manufacturers in 36 (75%) of the reported incidents. Reagents were frequently subject of manufacturing errors and biological contaminations, whereas analysing instruments were typically affected by software errors. In consequence, corrective actions were performed in the large majority of cases (n=37; 77.1%). These included customer information, product recalls, changes in production or quality management and software upgrades (the latter predominantly in cases of failures of analysing instruments). Our data suggest that the governmental system for marketing surveillance is an established tool to ensure product safety for IVD used in transfusion medicine.

Perforating injury allows the dispersion of environmental fungi and fungal spores together with miniscule foreign bodies into traumatized tissue where they can multiply and cause invasive infection. Acute invasive fungal infection after open fractures is uncommon. The severity of the fungal infections depends on the type of injury (perforating, presence of foreign material), the body area and the general condition of the patient. Fungal infections of the immuncompetent host are generally localized within the dermis, invasion of the fascia, muscles and the bone is rare. Injury-related fungal infections of the immuncompromised host may lead to rapid invasion and generalization of the fungal infection. The following review will focus on the fungal infections after perforating injuries and open fractures including the invasive mycoses as a direct consequence of the trauma, post-traumatic fungal infections, tropical fungal infections (mycetoma), invasive fungal infections after near-drowning and nosocomial invasive fungal infections of the critically ill post-traumatic patient admitted to the intensive care unit.

Diagnosing fungal infections remains a problem, particularly in the immunocompromised patient. Symptoms are mostly non-specific and colonization is difficult to distinguish from invasive disease. Existing diagnostic tools often lack sensitivity. Thus, the combination of various diagnostic tools is mandatory to allow earlier diagnosis of systemic fungal infections. Microscopy, culture based methods, antigen detection and molecular techniques such as PCR may help to facilitate and accelerate the diagnosis. Sensitive and specific PCR assays to detect fungal DNA are an important part of the diagnostic approach. But extensive validation and standardization is strongly needed before PCR assays can be used in a routine laboratory.

The basis for the diagnostic work-up of recurrent cystitis is formed by taking a precise medical history against the background of knowledge of the pathogenesis of urinary tract infections. The anamnesis should also focus on factors that influence the natural flora (sexual intercourse, hygiene) but additionally include preceding antibiotic treatment and diseases that affect the immune status (diabetes mellitus). Urinalysis is the principal examination among the laboratory diagnostic procedures. The diagnosis is promptly confirmed by immediate analysis of a clean catch midstream urine sample using a counting chamber or a test strip. As a matter of principle, microbiological diagnosis always ensues. Extended diagnostic work-up (urological staging) is aimed at detecting functional and anatomic abnormalities. While these factors only play a subordinate role during the premenopausal phase, they gain in importance during the postmenopausal phase. A key role is also attributed to local estrogen deficiency.

The spectrum of organisms causing dermatophytoses is changing continuously.Two strains of Trichophyton mentagrophytes var. nodulare are characterized mycologically; both were isolated for the first time in our laboratory within the past 2 years from patients with tinea pedis.Distinctive features of Trichophyton mentagrophytes var. nodulare are a bright yellow-orange pigmentation of the thallus, a marked exudation of pigment, and the development of nodular bodies. Trichophyton mentagrophytes var. nodulare is an anthropophilic variety of Trichophyton mentagrophytes causing tinea and onychomycosis.Trichophyton mentagrophytes var. nodulare has been found only very rarely in Germany and is relatively unknown. An increased awareness of this dermatophyte is needed in order to track its possible spread.

In the industrialized world the threat of infectious diseases is mainly due to nosocomial infections and multi-resistant agents. In this context, microbiological evaluations have not only a benefit for the individual patient, but also allow to evaluate the local epidemiologic situation. However, quality and benefits are often compromised by incorrect specimen collection. This review attempts to summarize diagnostic procedures, collection and transport of appropriate specimens and relevant causative agents for prominent clinical manifestations of infectious diseases.

This prospective study included 63 patients with confirmed infections of soft tissue, joints, bones or implants. During 110 surgical interventions, 124 swab and deep tissue sample pairs were taken and analysed microbiologically using standard procedures.In 40 patients who had not received prior antibiotic treatment, 57 sample pairs (swabs/tissue) were taken. In 70%, growth of microorganisms could be observed in both swabs and tissue samples. Growth in tissue sample only was observed in 14% and in 14% no growth could be detected. In 67 sample pairs taken from 23 patients who had received systemic antimicrobial treatment prior to surgery, microbial growth in both specimens was detected in 40%. Growth in tissue sample only was observed in 22% and 34% of the samples remained without detectable growth. The overall sensitivity of the tissue samples (70%) was significantly higher than in swab samples (44%) for the pretreated group.The use of intraoperative tissue samples for microbiological diagnostics in septic orthopaedic surgery must be considered a "gold standard". The higher sensitivity of intraoperative tissue samples is particularly important in patients receiving systemic antibiotic therapy prior to surgical interventions.

The assessment of mold concentrations in air samples requires generally accepted evaluation criteria. It is not possible to derive guideline values based on risk assessment. Background concentrations are therefore used as the basis for the assessment of measured concentrations. The assessment criteria established by the Federal Environmental Agency in Berlin and by the State Health Agency of Baden-Wurttemberg are founded on the experience of some laboratories. The general application of these criteria is only meaningful if validated and generally applied methods of analysis are used. Until now, laboratories have been using many different methods for sampling and detection of culturable molds and total spore counts in air. In this study, different steps for sampling by impaction or filtration are validated. The results presented will contribute to standardization of sampling and detection of molds in air.

Examination of dust samples is widely used to detect sources of mold growth in indoor environments. The advantage of this investigation is that house dust can be regarded as a passive sampler collecting mold spores over a long time period. No generally accepted method exists, however, for sampling and analysis of house dust for the detection of molds. Therefore, results obtained by different laboratories are not comparable. Measurements with standardized validated methods are a prerequisite to assess concentrations of molds in indoor environments. The method presented is based on sampling with a modified filter holder (in accordance with VDI 4300 page 8). Mini-sieves of different sizes are used for sample preparation. The fraction63 microm is used for cultivation of molds after suspension. Problems of dust sampling and preparation are discussed. Criteria for the detection of sources of mold growth based on dust samples are presented elsewere.

Mold concentrations of house dust samples from dwellings reportedly free from mold infestations were analysed to obtain background values. Samples from carpet floors were taken from 80 dwellings in three parts of Germany in winter and summer. Samples were analysed with the cultivation method (using suspension). This resulted in the detection of 35 mold species or genera. Concentrations of the genera Alternaria, Cladosporium, Fusarium and yeast increased in summer. In contrast concentrations of Aspergillus and Penicillium in the summer samples were nearly equal to those in the winter samples. The majority of the various molds were only found in a number of samples too small for a reliable comparison of the winter and summer findings to be made. The results were compared with findings of other authors. The authors propose the concentrations of the 95th percentile of each species (when representing over 10,000 KBE/g of dust) as background values, while a threefold higher value is regarded as an indication of mold presence. An exception should be made for the concentrations of molds which increase sharply in the outdoor air in summer. Because of the difficulty in estimating the outdoor influence, no evaluation proposals can be given for these species for the summer season.

Fungal spores are frequent in air and their occurrence in the nasal mucus appears to be a common finding within the adult population, as we were able to show in recent studies. 91,3 % of CRS patients but also healthy controls grew positive fungal cultures out of their nasal mucus. The potential role of fungal elements in nasal mucus for the pathogenesis of CRS, with or without polyposis, is currently investigated intensely and discussed very controversially. However, it was still unknown, as of when fungi could be cultured from nasal mucus in humans. We attempted to identify this point of time, in the nasal mucus of neonates.In our study we examined nasal mucus from 30 neonates immediately after birth, on the first and fourth day post partum, and after two and four months of life. The samples obtained with sterile cotton swabs were cultured on agar plates. Fungal cultures were identified either conventionally by microscopy or with molecular techniques. To show whether fungi in nasal mucus of newborns were acquired by contamination during birth, mucus of the maternal vagina was examined as well.Just after birth we found in 6 of 30 (20 %) of our neonates positive fungal cultures out of their nasal mucus, in 3 of them Candida albicans, probably due to contamination passing the maternal vagina as cultures of vaginal mucus of their mothers were positive for Candida albicans too. Positive fungal cultures were obtained in 2 of 29 (7 %) neonates on the second and in 4 of 26 (15 %) neonates on the fifth day of life. In all our cases initial presence in nasal mucus contamination just after birth or on the second day of life was limited to one day only. None of the 12 of 30 (40 %) neonates with positive fungal cultures from nasal mucus in the first 5 days of life showed clinical symptoms of nasal fungal colonisation. Besides Candida albicans, Penicillium sp., Cladosporium cladosporioides, Acremonium polychromum, Beauveria bassiana and Epicoccum nigrum could be detected in the first 5 days of life. After the second month of life, examination of nasal mucus yielded positive fungal cultures in 8 of 11 (72 %), after four months even 17 of 18 (94 %) of babies, with a wide array of different species.Fungi can be cultured from nasal mucus as soon as contact with the environmental air exists. Furthermore, a transfer of fungi from the mother's birth canal into the nose during birth is possible. Presence of fungal spores is common but not persistent in the nose of babies in the first days of life. However, after four months the situation is similar to the one in adults: fungal cultures can be obtained from almost everyone's nose. Therefore fungal spores must be considered a normal content of nasal mucus. Fungal spores are inhaled with every breath, some stick to the mucus, are transported to the nasopharynx and swallowed. This does not cause any clinical symptoms and is therefore not a pathological finding at all.