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Biomedical subjects

M Tvede

Publications and source records attributed to M Tvede.

At least 37 records · Page 2Linked to original sources
PubMed1996

Antibiotic-associated diarrhoea, Clostridium difficile, and short-chain fatty acids.

BACKGROUND: It has been hypothesized that Clostridium difficile and decreased colonic production of short-chain fatty acids (SCFAs) cause the development of antibiotic-associated diarrhoea. We therefore wanted to investigate the effects of an intensive and uniform antibiotic therapy on faecal SCFAs concentrations. C. difficile, and extent of diarrhoea. METHODS: Fifteen liver-transplanted patients who received oral bowel flora suppression therapy (6.3 g cefuroxime, 0.6 g tobramycin, and 0.5 g nystatin three times daily) were studied for 12 days before and 12 days after discontinuation of therapy. RESULTS: Thirteen of the 15 patients (87%) developed diarrhoea. Colonic fermentation was negligible in all patients, judged by very low levels of faecal SCFAs (< 10 mmol/l). Diarrhoea lessened as suppression therapy proceeded despite continuous low levels of SCFAs. Initial stool frequency of 4.1 +/- 0.6 and viscosity of 2.5 +/- 0.2 per day (on a scale of 1-3; mean +/- SE) decreased to 2.2 +/- 0.5 (p = 0.0009) and 1.6 +/- 0.2 (p = 0.003) per day, respectively, just before cessation of suppression therapy. Both SCFAs and stool habits normalized within days after discontinuation of antibiotics. Only a few samples from 2 patients were culture-positive for C. difficile during therapy, whereas 9 of the 15 patients (60%) became culture-positive (6 cytotoxin-positive) after cessation of suppression therapy at a time when none had diarrhoea. CONCLUSIONS: Intensive treatment with antibiotics directed against the colonic flora resulted in diarrhoea in the vast majority of patients, but the diarrhoea was self-limiting despite continual antibiotic treatment and very low faecal concentrations of SCFAs. C. difficile was not associated with antibiotic-associated diarrhoea but was a common finding after treatment with antibiotics was stopped at the time when diarrhoea had ceased.

Adult↗
PubMed1995

Prevalence and antibiotic sensitivity of Danish versus other European bacterial isolates from intensive care and hematology/oncology units.

The prevalence and antibiotic sensitivity patterns of bacteria collected consecutively from medical and surgical intensive care units (ICUs) and from hematology/oncology units in nine hospitals in Denmark were determined and compared to data collected simultaneously in 12 other European countries. Bacterial isolates from 794 Danish patients were tested and compared to 8,625 isolates from European patients. The minimal inhibitory concentrations of eight different antibiotics were determined using a microdilution plate. Similar to findings in European countries, the most common source of bacterial isolates in Danish units was the respiratory tract (49%), followed by blood (18%), urinary tract (14%) and surgical wounds (10%). Staphylococcus aureus was the most prevalent respiratory organism in Danish units, whereas Enterobacteriaceae and Pseudomonas aeruginosa dominated in other countries. In blood, Escherichia coli was most prevalent in Denmark while coagulase-negative staphylococci were predominant in other countries. Urinary tract isolates were dominated by Escherichia coli in both Denmark and the other countries, but Enterococcus faecalis and Pseudomonas aeruginosa were more frequently isolated in the other countries. Staphylococcus aureus was the most frequent wound isolate in Denmark, while Enterobacteriaceae other than Escherichia coli dominated in other European countries. Thus, in Denmark Escherichia coli and Staphylococcus aureus, followed by Pseudomonas aeruginosa and Klebsiella spp. (from ICUs) or Enterococcus spp. and Klebsiella spp. (from hematology/oncology units), are the most prominent pathogens in these units today. Indicator organisms of antibiotic consumption (Pseudomonas aeruginosa and methicillin-resistant coagulase-negative staphylococci and Staphylococcus aureus) were more frequent in other European countries than Denmark. In general the Danish isolates were more sensitive to antibiotics than the European isolates.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗
PubMed1995

Recrudescence and relapse of meningococcal meningitis and septicaemia.

Three cases of recrudescence and relapse of Neisseria meningitidis group B meningitis and septicaemia are reported. The recrudescence and relapses could not be explained by infectious foci, increased bacterial penicillin resistance or immunological defects. As a supplement to antibiotic treatment, all three patients received corticosteroids for the initial 2 days of treatment, and this may have contributed to the unusual course of the disease in our patient.

Administration, Oral↗
PubMed1994

Helicobacter pylori infection in children with recurrent abdominal pain.

Helicobacter pylori was cultured and Helicobacter-like organisms (HLO) were seen in 6 (16%) of 37 children with recurrent abdominal pain. Five children had concomitant histological inflammation, but none had endoscopic changes. All 6 children demonstrated positive serology. Compared with the total group, they were more often from developing countries, larger families and lower social groups. Treatment with phenoxymethyl penicillin and colloidal bismuth subcitrate did not result in side effects or elevated serum levels of serum bismuth. Three children demonstrated metronidazole-resistant strains and the treatment of these children remained an unsolved problem. Among the 31 H. pylori/HLO negative children 8 (26%) demonstrated histological changes, 5 (16%) endoscopic changes and 11 (35%) had positive serology. In conclusion, pathological findings at upper gastrointestinal endoscopy are common in children with recurrent abdominal pain. Because of disconcordance between endoscopy, histology and culture, we recommend that biopsies should always be taken to clarify the diagnosis.

Abdominal Pain↗
PubMed1994

IgG antibody response in bacterial endocarditis using ELISA with multiple antigens.

By means of enzyme-linked immunosorbent assays (ELISAs) the antibody responses were detected in sera from normal persons (n = 275), patients with various types of bacteremia (n = 137), and patients with endocarditis (n = 28). Four ELISAs were evaluated. As antigens ultrasonic extracts of Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, and nonhemolytic streptococci were used. The antibody levels against S. aureus increased with age, while antibodies against the other bacteria showed no age variation. The different ELISA systems showed many serological cross-reactions. The ELISA in this limited material was 72% successful in identifying cases of bacterial endocarditis caused by S. aureus (diagnostic sensitivity 84%; diagnostic specificity 89%), while in other cases of bacterial endocarditis it was less successful.

Adolescent↗
PubMed1994

The humoral immune response to Helicobacter pylori infection in children with recurrent abdominal pain.

The systemic humoral immune response to Helicobacter pylori antigens was investigated in 36 children with recurrent abdominal pain (RAP). H. pylori was cultured and Helicobacter-like organisms (HLO) were seen in six children, three of whom had active and two inactive chronic gastritis. None of these children had endoscopic abnormalities. All sex children had increased IgG antibodies to heat-stable H. pylori antigens which were of the IgG1 and IgG3 subclasses. Using six other IgG tests, four of which were commercially available, two to five H. pylori-positive children were found seropositive. Five of six H. pylori-negative children with inactive chronic gastritis and no endoscopic abnormalities had increased IgM antibody levels in addition to increased or borderline increased IgG antibody levels to H. pylori, indicating activity in a chronic H. pylori infection. Five children without H. pylori and with no morphological changes, but with gastritis or duodenitis by endoscopy, had significantly lower IgG and IgA antibody levels compared to other groups. Six of nineteen children without H. pylori, and with no morphological or endoscopic changes had increased IgG and IgM antibody levels to H. pylori. All H. pylori-negative children were seronegative by the four commercial kits. Overall, 12 (33%) of 36 children with RAP were either H. pylori positive by culture and microscopy or had increased IgG antibody levels to H. pylori, which is significantly different from the 10-14% seropositive rate of asymptomatic children. H. pylori may therefore be a cause of RAP in one quarter to one third of the children with RAP in whom other etiologies of RAP are excluded. Further studies on a large number of children are needed for an extended evaluation of the humoral immune response to H. pylori and for further examination of commercial kits which seem to give a high number of false-negative results.

Abdominal Pain↗
PubMed1993

Demonstration of toxin A and B by polymerase chain reaction and McCoy cell assay in clinical isolates of Clostridium difficile from Denmark.

A polymerase chain reaction (PCR) for demonstration of gene fragments of Clostridium difficile was established. One hundred and sixty-eight clinical isolates of C. difficile from three population groups were tested for production of cytotoxins by McCoy cell line assay (MCA) and for fragments of toxin A and B genes by PCR. The fragments for PCR amplification were at the 5' end of the toxin genes, which was found to be specific for C. difficile. Full agreement between the PCR and MCA results was found with respect to toxicity. Fifty-eight of the 168 strains were cytotoxin positive. Isolates from 41 normal healthy children did not differ regarding cytotoxicity compared to isolates from hospitalized children. In adult hospitalized patients a much higher frequency of toxin-producing isolates was found. In two strains from two children, not of the same family, only the toxin A gene fragment was demonstrated, indicating that some strains of C. difficile only harbour the gene for enterotoxin. When two isolates from different periods of time were tested from 36 of the healthy children, a variation in cytotoxicity was found: in seven children strains changed from non-toxic to toxic and in four vice versa. This may be explained by a fluctuating colonization of toxic and non-toxic C. difficile strains, or it may indicate the need for examination of more than one strain from a positive faecal sample to demonstrate cytotoxicity.

Adult↗
PubMed1993

Crossed immunoelectrophoresis used for bacteriological diagnosis in patients with endocarditis.

Sera from 151 patients suspected of having endocarditis were obtained during a period of 3 1/2 years at Rigshospitalet, Copenhagen. The sera were examined by crossed immunoelectrophoresis for antibodies to bacteria causing endocarditis. The patients were divided into four groups: 1. Patients with definite endocarditis, 2. Patients with culture-negative endocarditis, 3. Patients with uncertain endocarditis, and 4. Patients without endocarditis. In sera from patients suffering from endocarditis caused by viridans streptococci, precipitating antibodies were demonstrated by crossed immunoelectrophoresis (diagnostic specificity = 86%; diagnostic sensitivity = 100%) while other bacterial etiologies of endocarditis were less reliably demonstrated by this method.

Antibodies, Bacterial↗
PubMed1993

Collagenous colitis: are bacterial cytotoxins responsible?

In a case of collagenous colitis, cholestyramine treatment resulted in symptomatic and histological normalization. After discontinuation of cholestyramine, collagenous colitis relapsed. At this time fecal cytotoxic activity was demonstrated in McCoy cell lines. Symptoms, histologic changes, and cytotoxicity disappeared when cholestyramine treatment was reinstituted. We hypothesize that a bacterial toxin is responsible for the development of collagenous colitis.

Aged↗
PubMed1992

Short-chain fatty acids in pouch contents from patients with and without pouchitis after ileal pouch-anal anastomosis.

Fecal concentrations of short-chain fatty acids were markedly reduced in 6 patients with pouchitis (mean +/- SE, 56.2 +/- 13.3 mmol/L) compared with 28 patients without pouchitis (139.0 +/- 8.5 mmol/L; P less than 10(-3)). The ratios of acetate to propionate to butyrate were not changed (pouchitis, 75:12:11%; normal pouches, 76:12:11%), i.e., all acids were equally reduced. The 24-hour production of total short-chain fatty acids in 16.6% fecal homogenates from patients with pouchitis was decreased (17.5 +/- 5.3 mmol/L) compared with patients without pouchitis (33.3 +/- 3.4 mmol/L; P less than 0.05), which could be overcome by the addition of saccharides to the homogenates. Pouch excretions of saccharides were similar in the two groups, but dilution occurred during pouchitis because of the increased outputs. Concentrations and productions of short-chain fatty acids correlated with pouch concentrations and excretions of sodium and saccharides. L-Lactate was elevated in pouchitis outputs, but differences in stool culture counts, mucosal histology, fecal concentration, assimilation or production of ammonia, nitrogen excretion, pH, and osmolality were not found. Pouchitis is characterized by decreased fecal concentrations and productions of short-chain fatty acids possibly caused by low pouch concentrations of fermentable saccharides.

Adult↗
PubMed1992

High prevalence of Clostridium difficile diarrhoea during intensive chemotherapy for disseminated germ cell cancer.

A prospective, consecutive study of the aetiology of treatment-associated diarrhoea was conducted in 25 patients with disseminated germ cell cancer treated with intensive chemotherapy. Clostridium difficile was isolated in 45% of the diarrhoea episodes, which makes this species the most important bacterial pathogen in the development of clinically significant diarrhoea in this group of immunocompromised patients.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Experimental studies of survival of anaerobic bacteria at 4 degrees C and 22 degrees C in two different transport systems.

The survival of anaerobic bacteria on swabs in two different transport systems at 4 degrees C and 22 degrees C was evaluated. The transport systems were a charcoal-impregnated cotton swab in modified Stuart transport medium (MST), and a viscose swab in modified SIFF transport medium (BTM) (Bionor). The following eight clinical strains of anaerobic bacteria were tested for quantitative recovery at 24 h, 48 h, 72 h, and 96 h; Fusobacterium necrophorum, Bacteroides melaninogenicus, Bacteroides intermedius, Peptostreptococcus anaerobius, Peptococcus magnus, Clostridium perfringens, Clostridium tetani, and Actinomyces israelii. Additionally, a mixture of Staphylococcus aureus and Escherichia coli was tested together with Bacteroides fragilis, Fusobacterium necrophorum and Clostridium perfringens. Both transport systems preserved the bacteria, but the BTM medium gave a better quantitative recovery of the bacteria than the MST in 29/64 (45%) of the experiments, whereas the opposite was the case in 15/64 (23%) of the experiments (p < 0.05). There was no significant strain-related difference between the recovery of 10 different B. fragilis strains. There was no major difference in the recovery of the anaerobes in the two systems at 4 degrees C compared to 22 degrees C, except for Fusobacterium necrophorum, which survived best at 4 degrees C in the Bionor transport system.

Bacteria, Anaerobic↗
PubMed1991

[Generalized toxic symptoms caused by Clostridium difficile infection in a patient with Wilms' tumor].

This case report describes a 15 months-old patient with Wilms' tumor, who was treated with radical operation and chemotherapy. During hospitalization the patient suffered from recurrent lung infections, which were treated with appropriate antibiotics. Subsequently, the patient developed severe abdominal affection with daily melena, liver and kidney involvement, and generalized edema and hypertension. Cl. difficile and its cytotoxin was demonstrated in feces, and the patient was successfully treated with vancomycin. Although rare, Cl. difficile may cause severe generalised illness in children under two years of age, and it is important to examine any infant with abdominal symptoms for the occurrence of Cl. difficile, even though no diarrhoea is present.

Clostridioides difficile↗
PubMed1991

Colonic fermentation to short-chain fatty acids is decreased in antibiotic-associated diarrhea.

To elucidate the pathogenesis of antibiotic-associated diarrhea, colonic carbohydrate fermentation was investigated in three groups of subjects--a group of controls, a group of patients with antibiotic-associated diarrhea, and a group of patients receiving antibiotic therapy without diarrhea. Compared with controls, the colonic fermentation was markedly impaired in patients with antibiotic-associated diarrhea reflected by both very low concentrations (22.1 vs. 59.5 mmol/L; P less than 0.01) and production rates of short-chain fatty acids. In the group of patients without diarrhea, the effect on the colonic fermentation was dependent on the antibiotic administered. Penicillin and pivampicillin PO did not reduce the concentrations (69.9 and 66.7 mmol/L, respectively) or production rates. Dicloxacillin, erythromycin, and combined IV treatment with ampicillin, netilmicin, and metronidazole reduced both concentrations (27.1, 38.2, and 18.8 mmol/L; P less than 0.01) and production rates of short-chain fatty acids to levels seen in patients with diarrhea. L-Lactate and D-lactate concentrations were normal in all patients (less than 5 mmol/L), but lactate production was reduced in the patients who had reduced production of short-chain fatty acids, including patients with diarrhea. Thus, antibiotic-associated diarrhea was always related to reduced fecal concentrations and production rates of short-chain fatty acids and production rates of lactate. These results suggest that the antibiotic-associated diarrhea might be secondary to impaired colonic fermentation in otherwise disposed subjects, resulting in accumulation of luminal carbohydrate and/or decreased short-chain fatty acid-stimulated sodium and water absorption.

Adult↗
PubMed1991

Immunoglobulins of patients recovering from Yersinia enterocolitica infections exhibit Graves' disease-like activity in human thyroid membranes.

Substantial evidence suggests a link between infections with Yersinia enterocolitica (YE) and Graves' disease. We have now examined the sera of 72 patients recovering from YE infection for immunoglobulins that interacted with the TSH receptor in human thyroid membranes. Compared with controls, in concentrations between 1 and 4 mg/mL, patient IgG produced a significant, concentration-dependent inhibition of TSH binding (p less than 0.001) and stimulation of adenylate cyclase activity (p less than 0.005-0.05). Whereas IgG from normal individuals caused no stimulation of adenylate cyclase, IgG from controls caused some concentration-dependent displacement of TSH, as previously reported. However, IgG from convalescents of YE infections was significantly more potent than normal IgG in reducing the binding of TSH to the membrane. Thus, at each examined concentration, YE patients' IgG displaced more TSH than IgG from normal controls. For each milligram per milliliter increment of IgG in the assay, patients' IgG caused a 10.2% inhibition of TSH binding (r -0.90, p less than 0.001), significantly greater than that seen with normal IgG (p less than 0.02). The present studies provide the first demonstration that IgG of patients recovering from YE infections react with the human TSH receptor. The antibodies presumably are produced against the TSH-binding protein present in YE. However, in view of lack of evidence for thyroid dysfunction in the sera of patients recovering from yersiniosis and the presence of TSH-binding proteins in other bacteria, we postulate that infection with YE is neither necessary nor sufficient to cause thyroid autoimmune disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenylyl Cyclases↗
PubMed1990

Incidence of Clostridium difficile in hospitalized children. A prospective study.

A total of 394 children, aged 0-14 years, referred to a paediatric department were investigated for the occurrence of Clostridium difficile, its cytotoxin in faeces, and its clinical significance in a prospective study over one year. Of the children in the investigation, 337 suffered from gastrointestinal diseases or had been treated with antibiotics prior to the investigation. Twenty-four percent of these children had Cl. difficile in one or more faecal samples and toxin was demonstrated in half of these patients. In 18/148 (12%) of the patients with acute gastroenteritis Cl. difficile was isolated as the only pathogen. In contrast, among 57 control children with no gastrointestinal symptoms and no prior antibiotic treatment significantly fewer harboured Cl. difficile (p less than 0.01). Cl. difficile was isolated with similar frequency in children with or without prior antibiotic treatment. Isolation of Cl. difficile was significantly higher in patients under one year of age (p less than 0.001). In 78% of the patients with Cl. difficile the bacteria were found in faeces during the initial two days of hospitalization indicating that most of the cases were community acquired. The occurrence of Cl. difficile was not influenced by seasonal variation and the distribution between sexes was equal.

Adolescent↗
PubMed1989

Bacteriotherapy for chronic relapsing Clostridium difficile diarrhoea in six patients.

Six patients with chronic relapsing diarrhoea caused by Clostridium difficile were treated with rectal instillation of homologous faeces (one patient) or a mixture of ten different facultatively aerobic and anaerobic bacteria diluted in sterile saline (five patients). The mixture led to a prompt loss of Cl difficile and its toxin from the stools and to bowel colonisation by Bacteroides sp, which had not been present in pre-treatment stool samples. Strains of Escherichia coli, Cl bifermentans, and Peptostreptococcus productus in the mixture inhibited the in-vitro growth of Cl difficile, which in turn inhibited the growth of Bacteroides ovatus, Bacteroides vulgatus, and Bacteroides thetaiotaomicron. The finding that Bacteroides sp had been absent during the patients' illness but was present after recovery suggests that the absence of Bacteroides sp may result in chronic relapsing Cl difficile diarrhoea, and that its presence may prevent colonisation by Cl difficile.

Administration, Rectal↗