Rapid diagnosis of experimental meningitis by bacterial heat production in cerebrospinal fluid

BACKGROUND: Calorimetry is a nonspecific technique which allows direct measurement of heat generated by biological processes in the living cell. We evaluated the potential of calorimetry for rapid detection of bacterial growth in cerebrospinal fluid (CSF) in a rat model of bacterial meningitis. METHODS: Infant rats were infected on postnatal day 11 by direct intracisternal injection with either Streptococcus pneumoniae, Neisseria meningitidis or Listeria monocytogenes. Control animals were injected with sterile saline or heat-inactivated S. pneumoniae. CSF was obtained at 18 hours after infection for quantitative cultures and heat flow measurement. For calorimetry, 10 microl and 1 microl CSF were inoculated in calorimetry ampoules containing 3 ml trypticase soy broth (TSB). RESULTS: The mean bacterial titer (+/- SD) in CSF was 1.5 +/- 0.6 x 108 for S. pneumoniae, 1.3 +/- 0.3 x 106 for N. meningitidis and 3.5 +/- 2.2 x 104 for L. monocytogenes. Calorimetric detection time was defined as the time until heat flow signal exceeded 10 microW. Heat signal was detected in 10-microl CSF samples from all infected animals with a mean (+/- SD) detection time of 1.5 +/- 0.2 hours for S. pneumoniae, 3.9 +/- 0.7 hours for N. meningitidis and 9.1 +/- 0.5 hours for L. monocytogenes. CSF samples from non-infected animals generated no increasing heat flow (<10 microW). The total heat was the highest in S. pneumoniae ranging from 6.7 to 7.5 Joules, followed by L. monocytogenes (5.6 to 6.1 Joules) and N. meningitidis (3.5 to 4.4 Joules). The lowest detectable bacterial titer by calorimetry was 2 cfu for S. pneumoniae, 4 cfu for N. meningitidis and 7 cfu for L. monocytogenes. CONCLUSION: By means of calorimetry, detection times of <4 hours for S. pneumoniae and N. meningitidis and <10 hours for Listeria monocytogenes using as little as 10 microl CSF were achieved. Calorimetry is a new diagnostic method allowing rapid and accurate diagnosis of bacterial meningitis from a small volume of CSF.

Oxygen-sensitive 3He-MRI in bronchiolitis obliterans after lung transplantation

Oxygen-sensitive 3He-MRI was studied for the detection of differences in intrapulmonary oxygen partial pressure (pO2) between patients with normal lung transplants and those with bronchiolitis obliterans syndrome (BOS). Using software developed in-house, oxygen-sensitive 3He-MRI datasets from patients with normal lung grafts (n = 8) and with BOS (n = 6) were evaluated quantitatively. Datasets were acqiured on a 1.5-T system using a spoiled gradient echo pulse sequence. Underlying diseases were pulmonary emphysema (n = 10 datasets) and fibrosis (n = 4). BOS status was verified by pulmonary function tests. Additionally, 3He-MRI was assessed blindedly for ventilation defects. Median intrapulmonary pO2 in patients with normal lung grafts was 146 mbar compared with 108 mbar in patients with BOS. Homogeneity of pO2 distribution was greater in normal grafts (standard deviation pO2 34 versus 43 mbar). Median oxygen decrease rate during breath hold was higher in unaffected patients (-1.75 mbar/s versus -0.38 mbar/s). Normal grafts showed fewer ventilation defects (5% versus 28%, medians). Oxygen-sensitive 3He-MRI appears capable of demonstrating differences of intrapulmonary pO2 between normal lung grafts and grafts affected by BOS. Oxygen-sensitive 3He-MRI may add helpful regional information to other diagnostic techniques for the assessment and follow-up of lung transplant recipients.

Lactate and glucose concentrations in brain interstitial fluid, cerebrospinal fluid, and serum during experimental pneumococcal meningitis

Metabolic abnormalities during bacterial meningitis include hypoglycorrhachia and cerebrospinal fluid (CSF) lactate accumulation. The mechanisms by which these alterations occur within the central nervous system (CNS) are still incompletely delineated. To determine the evolution of these changes and establish the locus of abnormal metabolism during meningitis, glucose and lactate concentrations in brain interstitial fluid, CSF, and serum were measured simultaneously and sequentially during experimental pneumococcal meningitis in rabbits. Interstitial fluid samples were obtained from the frontal cortex and hippocampus by using in situ brain microdialysis, and serum and CSF were directly sampled. There was an increase of CSF lactate concentration, accompanied by increased local production of lactate in the brain, and a decrease of CSF-to-serum glucose ratio that was paralleled by a decrease in cortical glucose concentration. Brain microdialysate lactate concentration was not affected by either systemic lactic acidosis or artificially elevated CSF lactate concentration. These data support the hypothesis that the brain is a locus for anaerobic glycolysis during meningitis, resulting in increased lactate production and perhaps contributing to decreased tissue glucose concentration.

Two-step postmortem angiography with a modified heart-lung machine: preliminary results

OBJECTIVE: The purpose of this study was to adapt and improve a minimally invasive two-step postmortem angiographic technique for use on human cadavers. Detailed mapping of the entire vascular system is almost impossible with conventional autopsy tools. The technique described should be valuable in the diagnosis of vascular abnormalities. MATERIALS AND METHODS: Postmortem perfusion with an oily liquid is established with a circulation machine. An oily contrast agent is introduced as a bolus injection, and radiographic imaging is performed. In this pilot study, the upper or lower extremities of four human cadavers were perfused. In two cases, the vascular system of a lower extremity was visualized with anterograde perfusion of the arteries. In the other two cases, in which the suspected cause of death was drug intoxication, the veins of an upper extremity were visualized with retrograde perfusion of the venous system. RESULTS: In each case, the vascular system was visualized up to the level of the small supplying and draining vessels. In three of the four cases, vascular abnormalities were found. In one instance, a venous injection mark engendered by the self-administration of drugs was rendered visible by exudation of the contrast agent. In the other two cases, occlusion of the arteries and veins was apparent. CONCLUSION: The method described is readily applicable to human cadavers. After establishment of postmortem perfusion with paraffin oil and injection of the oily contrast agent, the vascular system can be investigated in detail and vascular abnormalities rendered visible.

[Diagnosis and therapy of depression in the heart disease patient]

Even though depressions and depressive symptoms are frequently observed in patients with medical diseases, their psychological problems are often neither diagnosed nor treated. Diagnosis of mood state might be easy in isolated cases yet it often is not since the precise nature of normal mood cannot be expressed in quantitative terms. Furthermore, depression can only be diagnosed based on the doctor's clinical appraisal and the patient's own description of his/her complaints. There is no gold standard on which depressive symptoms can be based on--and further on, depression is not a diagnosis. Instead, it is a syndrome that calls for differential diagnoses before treatment can be offered. Diagnosing depressive comorbidity in patients with medical complaints is even more difficult because of the overlap between symptoms of depression and accompanying symptoms of the somatic illness e.g. lack of energy. Although depressive states have been known to be a risk factor for the prognosis of patients with coronary heart disease for a long time, there is a paucity of research about the therapy these patients undergo due to the fact that tricyclic anti-depressants can have cardiotoxic effects on patients with heart disease. The treatment of depression in these patients has become a much lower risk since the introduction of serotonin reuptake inhibitors. There is widespread evidence that depressive comorbidity has a negative impact on the prognosis of medical disorders. Despite the complex nature of diagnosing depression, proper diagnosis and treatment is increasingly important in internal medicine and especially cardiology.

[Effects of tobacco use on general health: relevant information for dentistry (I)--part 1: pulmonary diseases and other malignancies]

This fifth part of a series of publications from the Swiss task force named "Smoking--Intervention in the private dental office" on the topic "tobacco use and dental medicine" focuses on the effects of tobacco use on general health. A significant increase of tobacco use associated morbidity and mortality for many cardiovascular and pulmonary diseases has been well documented in the literature. In this review, the epidemiologic background as well as the pathophysiological fundamentals for tobacco-mediated pulmonary diseases is presented, focusing especially on chronic obstructive pulmonary disease (COPD) and lung cancer. In addition, a causal relationship between nicotine abuse and an increased carcinoma incidence for other malignancies but lung cancer will be discussed. Regarding the evidence in the present literature, it is undisputable that smoking is the most preventable cause for COPD and lung cancer.

Patient satisfaction of primary care for musculoskeletal diseases: A comparison between Neural Therapy and conventional medicine

Background The main objective of this study was to assess and compare patient satisfaction with Neural Therapy (NT) and conventional medicine (COM) in primary care for musculoskeletal diseases. Methods A cross-sectional study in primary care for musculoskeletal disorders covering 77 conventional primary care providers and 18 physicians certified in NT with 241 and 164 patients respectively. Patients and physicians documented consultations and patients completed questionnaires at a one-month follow-up. Physicians documented duration and severity of symptoms, diagnosis, and procedures. The main outcomes in the evaluation of patients were: fulfillment of expectations, perceived treatment effects, and patient satisfaction. Results The most frequent diagnoses belonged to the group of dorsopathies (39% in COM, 46% in NT). We found significant differences between NT and COM with regard to patient evaluations. NT patients documented better fulfilment of treatment expectations and higher overall treatment satisfaction. More patients in NT reported positive side effects and less frequent negative effects than patients in COM. Also, significant differences between NT and COM patients were seen in the quality of the patient-physician interaction (relation and communication, medical care, information and support, continuity and cooperation, facilities availability, and accessibility), where NT patients showed higher satisfaction. Differences were also found with regard to the physicians' management of disease, with fewer work incapacity attestations issued and longer consultation times in NT. Conclusion Our findings show a significantly higher treatment and care-related patient satisfaction with primary care for musculoskeletal diseases provided by physicians practising Neural Therapy.

Wild-type and splice-variant secretin receptors in lung cancer: overexpression in carcinoid tumors and peritumoral lung tissue

Gastrointestinal peptide hormone receptors, like somatostatin receptors, are often overexpressed in human cancer, allowing receptor-targeted tumor imaging and therapy. A novel candidate for these applications is the secretin receptor recently identified in pancreatic and cholangiocellular carcinomas. In the present study, secretin receptors were assessed in a non-gastrointestinal tissue, the human lung. Non-small-cell lung cancers (n=26), small-cell lung cancers (n=10), bronchopulmonary carcinoid tumors (n=29), and non-neoplastic lung (n=46) were investigated for secretin receptor protein expression with in vitro receptor autoradiography, using (125)I-[Tyr(10)] rat secretin and for secretin receptor transcripts with RT-PCR. Secretin receptor protein expression was found in 62% of bronchopulmonary carcinoids in moderate to high density, in 12% of non-small cell lung cancers in low density, but not in small cell lung cancers. In tumors found to be secretin receptor positive by autoradiography, RT-PCR revealed transcripts for the wild-type secretin receptor and for novel secretin receptor splice variants. In the non-neoplastic lung, secretin receptor protein expression was observed in low density along the alveolar septa in direct tumor vicinity in cases of acute inflammation, but not in histologically normal lung. In the autoradiographically positive peritumoral lung, RT-PCR showed transcripts for the wild-type secretin receptor and for a secretin receptor spliceoform different from those occurring in lung and gut tumors. In conclusion, secretin receptors are new markers for bronchopulmonary carcinoid tumors, and represent the molecular basis for an in vivo targeting of carcinoid tumors for diagnosis and therapy. Furthermore, secretin receptors may play a role in peritumoral lung pathophysiology. Secretin receptor mis-splicing specifically occurs in tumor and non-tumor lung pathology.

Role for ephrinB2 in postnatal lung alveolar development and elastic matrix integrity

Alveoli are formed in the lung by the insertion of secondary tissue folds, termed septa, which are subsequently remodeled to form the mature alveolar wall. Secondary septation requires interplay between three cell types: endothelial cells forming capillaries, contractile interstitial myofibroblasts, and epithelial cells. Here, we report that postnatal lung alveolization critically requires ephrinB2, a ligand for Eph receptor tyrosine kinases expressed by the microvasculature. Mice homozygous for the hypomorphic knockin allele ephrinB2DeltaV/DeltaV, encoding mutant ephrinB2 with a disrupted C-terminal PDZ interaction motif, show severe postnatal lung defects including an almost complete absence of lung alveoli and abnormal and disorganized elastic matrix. Lung alveolar formation is not sensitive to loss of ephrinB2 cytoplasmic tyrosine phosphorylation sites. Postnatal day 1 mutant lungs show extracellular matrix alterations without differences in proportions of major distal cell populations. We conclude that lung alveolar formation relies on endothelial ephrinB2 function.

General laboratory diagnostics of eosinophilic GI diseases

Eosinophils and gastrointestinal tract interact in an intimate and enigmatic relationship. Under inflammatory conditions, eosinophil infiltration in the gastrointestinal tract is a common feature of numerous eosinophilic gastrointestinal disorders (EGIDs). EGIDs are disorders, for which the diagnosis is relatively difficult. Nevertheless, some common laboratory techniques are currently used for their diagnosis and disease monitoring. Besides eosinophils, mast cells and T cells have also been suggested to play a role in the pathogenesis of these disorders. Here, we review the pathogenesis and common laboratory approaches applied for their diagnosis, in particular eosinophil and mast cell markers.

Important research questions in allergy and related diseases: nonallergic rhinitis: a GA2LEN paper

Nonallergic rhinitis (NAR) can be defined as a chronic nasal inflammation which is not caused by systemic IgE-dependent mechanisms. It is common and probably affects far more than 200 million people worldwide. Both children and adults are affected. However, its exact prevalence is unknown and its phenotypes need to be evaluated using appropriate methods to better understand its pathophysiology, diagnosis and management. It is important to differentiate between infectious rhinitis, allergic/NAR and chronic rhinosinusitis, as management differs for each of these cases. Characterization of the phenotype, mechanisms and management of NAR represents one of the major unmet needs in allergic and nonallergic diseases. Studies on children and adults are required in order to appreciate the prevalence, phenotype, severity and co-morbidities of NAR. These studies should compare allergic and NAR and consider different age group populations including elderly subjects. Mechanistic studies should be carried out to better understand the disease(s) and risk factors and to guide towards an improved diagnosis and therapy. These studies need to take the heterogeneity of NAR into account. It is likely that neuronal mechanisms, T cells, innate immunity and possibly auto-immune responses all play a role in NAR and may also contribute to the symptoms of allergic rhinitis.

[Diagnostics of autoimmune diseases]

Autoantibodies play a key role in diagnostic laboratories as markers of autoimmune diseases. In addition to their role as markers they mediate diverse effects in vivo. Autoantibodies with protective effect have been described. Natural protective IgM autoantibodies against tumour-antigens of malignant cells or their precursors may contribute to increased survival rates of carcinoma patients. In a mouse model of systemic lupus erythematosus it has been shown that anti-dsDNA IgM autoantibodies protect from glomerular damage. In contrast, a direct pathogenic role of autoantibodies has been well established e.g. in myasthenia gravis or in Goodpasture syndrome. Similarly autoantibodies against SSA Ro52 are detrimental in neonatal lupus erythematosus with congenital heart block. Moreover, putatively protective autoantibodies may become pathogenic during the course of the disease such as the onconeuronal autoantibodies whose pathogenicity depends on their compartmentalisation. In patients with paraneoplastic syndromes tumour cells express proteins that are also naturally present in the brain. Anti-tumour autoantibodies which temporarily suppress tumour growth can provoke an autoimmune attack on neurons once having crossed the blood-brain barrier and cause specific neurological symptoms. Only a restricted number of autoantibodies are useful follow-up markers for the effectiveness of treatment in autoimmune diseases. Certain autoantibodies hold prognostic value and appear years or even decades before the diagnosis of disease such as the antimitochondrial antibodies in primary biliary cirrhosis or anti-citrullinated protein (CCP)-antibodies in rheumatoid arthritis. It is crucial to know whether the autoantibodies in question recognise linear or conformational epitopes in order to choose the appropriate detection methods. Indirect immunofluorescence microscopy remains a very useful tool for confirmation of results of commercially available immunoassays and for detection of special and rare autoantibodies that otherwise often remain undetected. Standardisation of autoimmune diagnostics is still underway and requires joint efforts by laboratories, clinicians and industry.

Moxifloxacin vs ampicillin/sulbactam in aspiration pneumonia and primary lung abscess

BACKGROUND: Aspiration pneumonia (AP) and primary lung abscess (PLA), are diseases following aspiration of infectious material from the oropharynx or stomach. An antibiotic therapy, also covering anaerobic pathogens, is the treatment of choice. In this study we compared moxifloxacin (MXF) and ampicillin/sulbactam (AMP/SUL) concerning efficacy and safety in the treatment of AP and PLA. METHODS: Patients with pulmonary infections following aspiration were included in a prospective, open-label, randomized, multicenter trial. Sequential antibiotic therapy with MXF or AMP/SUL was administered until complete radiologic and clinical resolution. RESULTS: A total of 139 patients with AP and PLA were included, 96 were evaluable for efficacy (EE, 48 patients in each treatment group). The overall clinical response rates in both groups were numerically identical (66.7%). MXF and AMP/SUL were both well tolerated, even after long-term administration [median duration of treatment (range) in days MXF versus AMP/SUL: AP 11 (4-45) vs 9 (3-25), PLA 30.5 (7-158) vs 35 (6-90)]. CONCLUSION: In the treatment of aspiration-associated pulmonary infections moxifloxacin appears to be clinically as effective and as safe as ampicillin/sulbactam; but, however, having the additional benefit of a more convenient (400 mg qd) treatment.