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Biomedical subjects

J W van der Meer

Publications and source records attributed to J W van der Meer.

At least 19 recordsLinked to original sources

[Clinical reasoning and decision making in practice. A man with pneumonia and ill smelling watery sputum: the truth revealed after 80 years].

A 24-year-old man was admitted to hospital with pneumonia. On admission he was seen to have an asymmetrical build. During treatment of the lung infiltrate his clinical condition deteriorated. On the third day he coughed up great quantities of fluid which had a urine-like smell. The concentration of creatinine in this fluid was the same as in urine. On X-ray of the thorax, a massive accumulation of pleural fluid was seen. Shortly after aspiration of 1000 ml of pleural fluid the patient died. At autopsy, an ectopic kidney was found in the left thoracic cavity. The pneumonia had caused an abscess that had broken into the pelvis of this ectopic kidney causing the loss of urine into the pleural cavity (urothorax) and 'uroptysis'. On the basis of anatomical and embryological aspects it is debatable if this case was genuine. It is in fact a duplication of a case report published in this journal in 1923 the reliability of which was never clarified. Biographical information from Professor A. Querido (1901-1983) which has since become available indicates that the case was faked by mischievous medical students preparing for their examinations. They had never imagined that the editors might actually accept it for publication. The case report of 1923 has now been retracted.

Adult↗

[Research into new methods for diagnosing, treating and preventing tuberculosis].

Tuberculosis control requires improved diagnostics, drugs, and vaccines. Their development is facilitated by progress in immunology, molecular biology, and genomics. In addition to sputum smear and culture, amplification techniques can already be used to diagnose tuberculosis and antigen-detection tests for this purpose are being developed. Molecular typing and DNA microarrays provide new insights in the natural history and transmission of tuberculosis. In addition to established drugs such as rifampicin, isoniazid, pyrazinamide, and ethambutol, a limited number of new drugs have been discovered such as rifampicin derivates and fluorochinolones. Improved screening techniques and insights from genomics may lead to new drugs being discovered. Factors hampering the development and evaluation of new vaccines include problems with extrapolation from animal models, incomplete natural immunity, and limited knowledge about protective immunity. However, new candidate vaccines are being developed and will be tested on humans in the near future.

Animals↗

[Hemopyrrollactamuria (HPU); from spots to pseudo-disease].

In recent years, patients in the Netherlands confront their doctors with the diagnosis 'haemopyrollactamuria' (HPU), based on the presence of the haemopyrrollactam complex in their urine. The diagnosis is made by a commercial laboratory in the Netherlands (www.keac.nl). We have not been able to find peer-reviewed scientific literature on this metabolic disease. The haemopyrrollactam complex represents the so-called mauve spot, which was the subject of much controversy in schizophrenia research in the previous century. Reviewing all of the available data, we feel that HPU should be classified as a pseudo-disease.

Humans↗

Genetic analysis as a valuable key to diagnosis and treatment of periodic Fever.

We describe 2 Dutch patients with recurrent fever attacks undiagnosed for more than 40 years. The diagnosis of periodic fever was made when molecular analysis revealed novel mutations in the tumor necrosis factor (TNF) receptor gene (TNFRSF1A), establishing the diagnosis of TNF receptor-associated periodic syndrome. This syndrome is an autosomal dominant disorder characterized by recurring episodes of fever, arthralgia, and skin lesions that is caused by mutations in the 55-kd TNFRSF1A gene. This finding has facilitated treatment for TNF receptor-associated periodic syndrome because blocking of TNF signaling seems to alleviate the symptoms. Use of a short course of recombinant p75TNFR:Fc fusion protein (etanercept) induced prolonged remission in one patient.

Anti-Inflammatory Agents, Non-Steroidal↗

Cognitive behaviour therapy for chronic fatigue syndrome: a multicentre randomised controlled trial.

BACKGROUND: Cognitive behaviour therapy (CBT) seems a promising treatment for chronic fatigue syndrome (CFS), but the applicability of this treatment outside specialised settings has been questioned. We compared CBT with guided support groups and the natural course in a randomised trial at three centres. METHODS: Of 476 patients diagnosed with CFS, 278 were eligible and willing to take part. 93 were randomly assigned CBT (administered by 13 therapists recently trained in this technique for CFS), 94 were assigned the support-group approach, and 91 the control natural course. Multidimensional assessments were done at baseline, 8 months, and 14 months. The primary outcome variables were fatigue severity (on the checklist individual strength) and functional impairment (on the sickness impact profile) at 8 and 14 months. Data were analysed by intention to treat. FINDINGS: 241 patients had complete data (83 CBT, 80 support groups, 78 natural course) at 8 months. At 14 months CBT was significantly more effective than both control conditions for fatigue severity (CBT vs support groups 5.8 [2.2-9.4]; CBT vs natural course 5.6 [2.1-9.0]) and for functional impairment (CBT vs support groups 263 [38-488]; CBT vs natural course 222 [3-441]). Support groups were not more effective for CFS patients than the natural course. Among the CBT group, clinically significant improvement was seen in fatigue severity for 20 of 58 (35%), in Karnofsky performance status for 28 of 57 (49%), and self-rated improvement for 29 of 58 (50%). Prognostic factors for outcome after CBT were a higher sense of control predicting more improvement, and a passive activity pattern and focusing on bodily symptoms predicting less improvement. INTERPRETATION: CBT was more effective than guided support groups and the natural course in a multicentre trial with many therapists. Our study showed a lower proportion of patients with improvement than CBT trials with a few highly skilled therapists.

Adult↗

[From gene to disease; tumor necrosis factor receptor and a syndrome of familial periodic fever].

Familial Hibernian fever (FHF) is a rare hereditary syndrome that causes periodic attacks of fever and inflammation. It is an autosomal dominantly inherited disorder. The gene involved in FHF encodes for a receptor for tumour necrosis factor (TNFR1). These mutations are thought to result in impaired shedding of the receptor from the cell membrane, leading to deficient curtailing of the inflammatory reaction. The acronym TRAPS (TNF-receptor associated periodic syndrome) has been proposed as a more accurate name.

Alleles↗

[Diagnostic image (19). Ecthyma gangraenosum].

During chemotherapy for acute myeloid leukaemia a 30-year-old man developed skin lesions. Cultures from these lesions and of blood showed growth of Pseudomonas aeruginosa. The diagnosis was: ecthyma gangraenosum. Treatment with antibiotics and normalization of the granulocytes resulted in a complete recovery of the patient.

Acute Disease↗

Common variable immunodeficiency (CVID) in a family: an autosomal dominant mode of inheritance.

BACKGROUND: Common variable immunodeficiency (CVID) is characterised by a late onset deficiency of immunoglobulins resulting in recurrent infectious and non-infectious ailments. Most cases are sporadic but occasional familial clustering has been described. We present an extensively affected family with CVID in three consecutive generations. METHODS: We conducted a study in this family to establish clinical phenotype, to clarify the mode of inheritance and to attempt to characterise the immune disturbance by determining immunoglobulin concentrations and B- and T-cell analysis. RESULTS: We describe six patients with CVID in three consecutive generations. In addition, we encountered 10 family members with dysimmunoglobulinemia. B-cell counts were normal, but T-cell analysis showed slightly abnormal results. CONCLUSIONS: The six cases of overt late onset hypogammaglobulinemia are compatible with an autosomal dominant mode of inheritance. The family members with dysimmunoglobulinemia may be at risk to develop overt CVID in the future, in view of the gradual course of progression of the disease in the clinically affected family members. B- and T-cell analysis are inconclusive though may support a possible defect in T-cell function to be involved. To further study this remarkable family and attempt to clarify pathogenesis, we are planning DNA linkage analysis in the near future.

Adult↗

Molecular analysis of MVK mutations and enzymatic activity in hyper-IgD and periodic fever syndrome.

Hyperimmunoglobulinaemia D and periodic fever syndrome (HIDS) is an autosomal recessive inflammatory disorder characterised by recurrent episode of fever associated with lymphadenopathy, abdominal distress, joint involvement and skin lesions. We recently demonstrated that mutations in the mevalonate kinase gene (MVK) are associated with HIDS. Direct DNA sequencing was done to screen the entire coding region of MVK in 25 unrelated patients with HIDS. Mutations were detected in the coding region of the gene including 11 missense mutations, one deletion, the absence of expression of one allele, as well as three novel polymorphisms. Seven of these mutations are novel. The large majority of the patients were compound heterozygotes for two mutations. Of these, V377I (G-->A) is the most common mutation occurring in 20 unrelated patients and was found to be associated with I268T in six patients. Mutations were associated with a decrease of mevalonate kinase (MK) (ATP:mevalonate 5-phosphotransferase, EC 2.7.I.36) enzymatic activity but not as profound as in mevalonic aciduria, a syndrome also caused by a deficient activity of MK. In HIDS the mutations are located all along the protein which is different from mevalonic aciduria where MK mutations are mainly clustered to a same region of the protein. On the basis of this study, we propose that the diagnostic screen of MVK in HIDS should be first directed on V377I and I268T mutations. Three patients are also described to illustrate the genotypic and phenotypic overlap with mevalonic aciduria.

Adult↗

Quality of antimicrobial drug prescription in hospital.

There is worldwide concern about the development of antimicrobial resistance [1]. Selective pressure by antimicrobial drugs is by far the most important driving force for the development of resistance. Antimicrobial drugs are among the most commonly prescribed drugs in hospitals. In developed countries, some 30% of the hospitalized patients will be treated with these drugs. It is generally accepted that antimicrobial prescribing is often suboptimal, even in a country like the Netherlands, where both antibiotic consumption and microbial resistance rates are low [2,3]. The major problem with inappropriate prescribing is because of insufficient education in infectious diseases and antimicrobial therapy. Often, the prescription of these drugs with little toxicity is unjustified because of insecurity about the diagnosis of the clinician; 'drugs of fear' [4]. In our surveys, some 15% of the antibiotic prescriptions in surgical and internal medicine wards were considered unjustified [5,6]. Many prescribers are not yet fully aware that their justified or unjustified prescription adds to the resistance problem. In this paper, aspects of the quality of antimicrobial prescribing in the hospital setting will be discussed.

Advertising↗

Use of fluconazole in daily practice: still room for improvement.

One hundred courses of fluconazole treatment in a university hospital and 81 courses in a non-university teaching hospital have been analysed in a prospective audit to evaluate prescribing practices. The quality of treatments was assessed by an infectious disease specialist and a pharmacist according to standard guidelines. In the non-university hospital, prescribed dosages were lower than in the university hospital, and often below the recommended dose. Mean duration of treatment for oesophageal candidosis and disseminated infections was considerably shorter in the non-university hospital compared with the university hospital, and often judged too short. Microbiological samples were examined in 75% of the cases in both hospitals. The expert reviewers agreed with the indication to use fluconazole in 58-100% of cases in the university hospital and 42-80% in the non-university hospital, depending on the type of infection. There did not appear to be a major problem with inappropriate use of fluconazole. However, important issues for improvement could be identified, such as increasing the dosage and duration of treatment in cases of serious infections, and withholding treatment from patients with colonization rather than infection.

Adult↗

In vivo efficacy of trovafloxacin against Bacteroides fragilis in mixed infection with either Escherichia coli or a vancomycin-resistant strain of Enterococcus faecium in an established-abscess murine model.

The pharmacodynamic and pharmacokinetic properties of trovafloxacin were studied in a standardized murine model of established subcutaneous abscesses. Daily dosing regimens of 37.5 to 300 mg/kg every 8 h (q8h) or every 24 h (q24h) were started 3 days after inoculation with mixtures containing either Bacteroides fragilis-Escherichia coli-autoclaved cecal contents (ACC) or B. fragilis-vancomycin-resistant Enterococcus faecium (VREF)-ACC. Treatment was continued for 3 or 5 days. The efficacy of treatment was determined by the decrease in abscess bacterial counts and abscess weights, as well as by the reduction in inflammation (biodistribution of (99m)Tc-HYNIC immunoglobulin G) compared to saline-treated controls. Trovafloxacin showed a significant dose-response effect on the bacterial counts, weight, and inflammation of B. fragilis-E. coli abscesses after 3 and/or 5 days of treatment. A maximum 3.4 and 3.1 log(10) reduction in CFU/abscess in the respective B. fragilis and E. coli bacterial counts was attained after 5 days of treatment with daily doses of 300 mg/kg. The peak serum concentration was more predictive for effect than the area under the concentration-time curve. The C(max) was the pharmacodynamic index most predictive for success, and the efficacy of the q24h regimens was significantly better than the q8h regimens. The antibiotic was ineffective against the VREF in mixed infection with B. fragilis, while the killing of the anaerobe in the same combination was significantly less than in the E. coli combination (P < 0.05). We conclude that this is a useful model for studying the activity of antimicrobials for the treatment of small (<1-cm), undrainable, mixed-infection abscesses. In addition, we have shown for the first time that a decrease in bacterial numbers also leads to a reduction in both abscess weight and inflammation.

Abscess↗

Hyper-immunoglobulin A in the hyperimmunoglobulinemia D syndrome.

The hyperimmunoglobulinemia D syndrome (HIDS) is an autosomal recessive disorder characterized by recurrent febrile attacks with abdominal, articular, and skin manifestations. Apart from elevated immunoglobulin D (IgD) levels (>100 IU/ml), there are high IgA levels in the majority of cases. Mutations in the gene encoding mevalonate kinase constitute the molecular defect in HIDS. The cause of elevated IgA concentrations in HIDS patients remains to be elucidated. We studied the hyper-IgA response in serum of a group of HIDS patients. Elevated IgA concentrations result from increased IgA1 concentrations. IgA and IgA1 concentrations correlated significantly with IgD concentrations, and levels of IgA polymers were significantly higher than the levels in healthy donors. These results indicate a continuous, presumably systemic, stimulation of IgA in HIDS patients.

Adolescent↗