Treatment of active rheumatoid arthritis with leflunomide compared with placebo and methotrexate. Leflunomide Rheumatoid Arthritis Investigators Group

CONTEXT

Leflunomide is a reversible inhibitor of de novo pyrimidine synthesis shown to be effective in a phase 2 trial in 402 patients with active rheumatoid arthritis (RA).

OBJECTIVE

To compare the efficacy and safety of leflunomide treatment with placebo and methotrexate treatment in patients with active RA.

DESIGN

Randomized, double-blind, placebo, and active-controlled 12-month study.

SETTING

Forty-seven university and private rheumatology practices in the United States and Canada.

PATIENTS

Diagnosis of RA by the American College of Rheumatology (ACR) criteria for duration of 6 months or longer and no previous methotrexate treatment.

INTERVENTION

Leflunomide treatment (20 mg/d), placebo, or methotrexate treatment (7.5-15 mg/wk).

MAIN OUTCOME MEASURES

American College of Rheumatology success rate (completed 52 weeks of treatment and met the ACR > or = 20% response criteria), disease progression as assessed by x-ray films, and improvement in function and health-related quality of life using the intent-to-treat population.

RESULTS

The 482 patients studied were predominantly women (mean age, 54 years; mean disease duration, 6.7 years) for whom a mean of 0.8 disease-modifying antirheumatic drugs had failed. The ACR response and success rates for patients receiving leflunomide treatment (52% and 41%, respectively) and methotrexate treatment (46% and 35%, respectively) were significantly higher than those for patients receiving placebo (26% and 19%, respectively) (P<.001), and they were statistically equivalent, with mean time to initial response at 8.4 weeks for patients receiving leflunomide vs 9.5 weeks for patients receiving methotrexate therapy. X-ray analyses demonstrated less disease progression with leflunomide (P=.001) and methotrexate (P = .02) therapy than with placebo. Leflunomide and methotrexate treatment improved measures of physical function and health-related quality of life significantly more than placebo (P<.001 and P<.05, respectively). Common adverse events for patients receiving leflunomide treatment included gastrointestinal complaints, skin rash, and reversible alopecia. Asymptomatic transaminase elevations resulted in treatment discontinuations for 7.1% of patients receiving leflunomide therapy, 1.7% of patients receiving placebo, and 3.3% of patients receiving methotrexate therapy.

CONCLUSIONS

Clinical responses following administration of leflunomide, a new therapeutic agent for the treatment of RA, were statistically superior to those with placebo and equivalent to those with methotrexate treatment. Both active treatments improved signs and symptoms of active RA, delayed disease progression as demonstrated by x-ray films, and improved function and health-related quality of life.

Antibiotic therapy for Pseudomonas aeruginosa bacteremia: outcome correlations in a prospective study of 200 patients

PURPOSE AND PATIENTS AND METHODS

We performed a prospective clinical study of 200 consecutive patients with Pseudomonas aeruginosa bacteremias to analyze in vitro susceptibility and synergistic testing of antibiotics the patients received and clinical parameters to assess their relationship to survival.

RESULTS

No significant correlation between in vitro susceptibility testing (minimal inhibitory concentrations/minimal bactericidal concentrations) and outcome could be demonstrated. Similarly, improved outcome could not be demonstrated for patients receiving antibiotic combinations that were synergistic in vitro (either time-kill or checker-board) versus those combinations that were not. There was also no correlation between results obtained by time-kill curve and checkerboard synergistic testing, i.e., combinations found to be synergistic by one method were not necessarily synergistic by the other method. Clinical parameters associated with improved survival were a urinary portal of entry and absence of neutropenia. Conversely, survival was significantly decreased when the portal was the respiratory tract. The mortality rate between patients receiving combination therapy (27%) and monotherapy (47%) was significant (p less than 0.02); this significant relationship held true for most subgroups including malignancy, nosocomial infection, and infection site.

CONCLUSION

Increasing effort should be placed on ensuring timely administration of combination therapy to patients with P. aeruginosa bacteremia since the use of combination therapy was even more important in determining outcome than was underlying disease.

The neuronal ceroid lipofuscinoses in human EPMR and mnd mutant mice are associated with mutations in CLN8

The neuronal ceroid lipofuscinoses (NCLs) are a genetically heterogeneous group of progressive neurodegenerative disorders characterized by the accumulation of autofluorescent lipopigment in various tissues. Progressive epilepsy with mental retardation (EPMR, MIM 600143) was recently recognized as a new NCL subtype (CLN8). It is an autosomal recessive disorder characterized by onset of generalized seizures between 5 and 10 years, and subsequent progressive mental retardation. Here we report the positional cloning of a novel gene, CLN8, which is mutated in EPMR. It encodes a putative transmembrane protein. EPMR patients were homozygous for a missense mutation (70C-->G, R24G) that was not found in homozygosity in 433 controls. We also cloned the mouse Cln8 sequence. It displays 82% nucleotide identity with CLN8, conservation of the codon harbouring the human mutation and is localized to the same region as the motor neuron degeneration mouse, mnd, a naturally occurring mouse NCL (ref. 4). In mnd/mnd mice, we identified a homozygous 1-bp insertion (267-268insC, codon 90) predicting a frameshift and a truncated protein. Our data demonstrate that mutations in these orthologous genes underlie NCL phenotypes in human and mouse, and represent the first description of the molecular basis of a naturally occurring animal model for NCL.

Two-year, blinded, randomized, controlled trial of treatment of active rheumatoid arthritis with leflunomide compared with methotrexate. Utilization of Leflunomide in the Treatment of Rheumatoid Arthritis Trial Investigator Group

OBJECTIVE

Three 6-12-month, double-blind, randomized, controlled trials have shown leflunomide (LEF; 20 mg/day, loading dose 100 mg x 3 days) to be effective and safe for the treatment of rheumatoid arthritis (RA). This analysis of the North American trial assessed whether the clinical benefit evident at month 12 was sustained over 24 months of treatment with LEF as compared with the efficacy and safety of methotrexate (MTX), an equivalent disease-modifying antirheumatic drug, at 24 months.

METHODS

The year-2 cohort, comprising patients continuing into the second year of treatment with > or = 1 dose of study medication and > or = 1 followup visit after week 52, consisted of 235 patients (LEF n = 98; placebo n = 36; MTX n = 101). The mean (+/- SD) maintenance dose of LEF was 19.6 +/- 1.99 mg/day in year 2 and that of MTX was 12.6 +/- 4.69 mg/week. Statistical analyses used an intent-to-treat (ITT) approach. Statistical comparisons of the active treatments only were prospectively defined in the protocol.

RESULTS

In total, 85% and 79% of LEF and MTX patients, respectively, who entered year 2 completed 24 months of treatment. From month 12 to month 24, the American College of Rheumatology improvement response rates of > or = 20% (LEF 79% versus MTX 67%; P = 0.049), > or = 50% (LEF 56% versus MTX 43%; P = 0.053), and > or = 70% (LEF 26% versus MTX 20%; P = 0.361) were sustained in both of the active treatment groups. The mean change in total Sharp radiologic damage scores at year 2 compared with year 1 and baseline (LEF 1.6 versus MTX 1.2) showed statistically equivalent sustained retardation of radiographic progression in the active treatment groups. Maximal improvements evident at 6 months in the Health Assessment Questionnaire (HAQ) disability index (HAQ DI) and the physical component score of the Medical Outcomes Survey 36-item short form were sustained over 12 months and 24 months; improvement in the HAQ DI with LEF4(-0.60) was statistically significantly superior to that with MTX (-0.37) at 24 months (P = 0.005). Over 24 months in the ITT cohort, serious treatment-related adverse events were reported in 1.6% of the LEF-treated patients and 3.7% of the MTX-treated patients. Frequently reported adverse events included upper respiratory tract infections, diarrhea, nausea and vomiting, rash, reversible alopecia, and transient liver enzyme elevations.

CONCLUSION

The safety and efficacy of LEF and MTX were maintained over the second year of this 2-year trial. Both active treatments retarded radiographic progression over 24 months. LEF was statistically significantly superior to MTX in improving physical function as measured by the HAQ DI over 24 months of treatment. Results indicate that LEF is a safe and effective initial treatment for active RA, with clinical benefit sustained over 2 years of treatment without evidence of new or increased toxicity.

Spontaneous Atlanto-Axial Dislocation in Ankylosing Spondylitis and Rheumatoid Arthritis

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Natural history of rheumatoid cervical luxations

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Cytosolic phospholipase A2 is induced in reactive glia following different forms of neurodegeneration

Many recent studies have emphasized the deleterious role of inflammation in CNS injury. Increases in free fatty acids, eicosanoids, and products of lipid peroxidation are known to occur in various conditions of acute and chronic CNS injury, including cerebral ischemia, traumatic brain injury, and Alzheimer's disease. Although an inflammatory response can be induced by many different means, phospholipases, such as cytosolic phospholipase A(2) (cPLA(2)), may play an important role in the production of inflammatory mediators and in the production of other potential second messengers. cPLA(2) hydrolyzes membrane phospholipids and its activity liberates free fatty acids leading directly to the production of eicosanoids. We investigated the cellular localization of cytosolic phospholipase A(2) in the CNS following: (1) focal and global cerebral ischemia, (2) facial nerve axotomy, (3) human cases of Alzheimer's disease, (4) transgenic mice overexpressing mutant superoxide dismutase, a mouse model of amyotrophic lateral sclerosis, and (5) transgenic mice overexpressing mutant amyloid precursor protein, which exhibits age-related amyloid deposition characteristic of Alzheimer's disease. We show that in every condition evaluated, cytosolic phospholipase A(2) is present in reactive glial cells within the precise region of neuron loss. In conditions where neurons did not degenerate or are protected from death, cytosolic phospholipase A(2) is not observed. Both astrocytes and microglial cells are immunoreactive for cytosolic phospholipase A(2) following injury, with astrocytes being the most consistent cell type expressing cytosolic phospholipase A(2). The presence of cytosolic phospholipase A(2) does not merely overlap with reactive astroglia, as reactive astrocytes were observed that did not exhibit cytosolic phospholipase A(2) immunoreactivity. In most conditions evaluated, inflammatory processes have been postulated to play a pivotal role and may even participate in neuronal cell death. These results suggest that cytosolic phospholipase A(2) may prove an attractive therapeutic target for neurodegeneration.

One Health contributions towards more effective and equitable approaches to health in low- and middle-income countries

Emerging zoonoses with pandemic potential are a stated priority for the global health security agenda, but endemic zoonoses also have a major societal impact in low-resource settings. Although many endemic zoonoses can be treated, timely diagnosis and appropriate clinical management of human cases is often challenging. Preventive 'One Health' interventions, e.g. interventions in animal populations that generate human health benefits, may provide a useful approach to overcoming some of these challenges. Effective strategies, such as animal vaccination, already exist for the prevention, control and elimination of many endemic zoonoses, including rabies, and several livestock zoonoses (e.g. brucellosis, leptospirosis, Q fever) that are important causes of human febrile illness and livestock productivity losses in low- and middle-income countries. We make the case that, for these diseases, One Health interventions have the potential to be more effective and generate more equitable benefits for human health and livelihoods, particularly in rural areas, than approaches that rely exclusively on treatment of human cases. We hypothesize that applying One Health interventions to tackle these health challenges will help to build trust, community engagement and cross-sectoral collaboration, which will in turn strengthen the capacity of fragile health systems to respond to the threat of emerging zoonoses and other future health challenges. One Health interventions thus have the potential to align the ongoing needs of disadvantaged communities with the concerns of the broader global community, providing a pragmatic and equitable approach to meeting the global goals for sustainable development and supporting the global health security agenda.This article is part of the themed issue 'One Health for a changing world: zoonoses, ecosystems and human well-being'.

Rheumatoid arthritis joint progression in sustained remission is determined by disease activity levels preceding the period of radiographic assessment

OBJECTIVE

Joint damage is related to disease activity in rheumatoid arthritis (RA), but the degree of its progression and the temporal associations between disease activity and joint damage are unclear. The aim of this study was to evaluate whether there is a latency in the effect of disease activity on radiographic progression in patients with RA.

METHODS

Data were obtained from the PREMIER trial, a 2-year randomized, controlled clinical trial of adalimumab plus methotrexate versus methotrexate alone or adalimumab alone in early RA. Radiographic progression of joint damage was calculated using the modified total Sharp score in a subset of patients whose disease was in remission (Simplified Disease Activity Index<or=3.3) in the second year of the trial. The progression of damage in the second year was compared between groups of patients whose disease was already in remission for an additional period of 3, 6, or 9 months during the first year. Analysis of variance was used to test for a linear trend.

RESULTS

Among 794 patients with early RA, 119 (15%) achieved sustained remission during the second year, with no difference in radiographic progression across the 3 treatment groups. Radiographic progression in the second year was significantly different between patients with 3, 6, or 9 additional months of remission during year 1 (mean change in the modified Sharp score 1.19 in those with 3 additional months of remission versus 0.20 in those with 6 additional months of remission and -0.32 in those with 9 additional months of remission; P<0.05). The results were supported by similar findings in a series of sensitivity analyses.

CONCLUSION

These data indicate that the level of disease activity as well as the duration of remission affect subsequent progression of radiographic damage in RA. This latency between disease activity and its effects on radiographic progression should be considered when evaluating radiographic outcomes in trials of RA.

Association study of a dopamine transporter polymorphism and attention deficit hyperactivity disorder in UK and Turkish samples

Molecular genetic studies in attention deficit hyperactivity disorder (ADHD) have focussed on candidate genes within the dopamine system, which is thought to be the main site of action of stimulant drugs, the primary pharmacological treatment of the disorder. Of particular interest are findings with the dopamine transporter gene (DAT1), since stimulant drugs interact directly with the transporter protein. To date, there have been eight published association studies of ADHD with a 480 base-pair allele of a variable number tandem repeat (VNTR) polymorphism in the 3'-untranslated region of the gene, five that support an association and three against. We have analysed the same VNTR marker in a dataset of UK Caucasian children and an independent dataset of Turkish Caucasian children with DSM-IV ADHD, using the transmission disequilibrium test (TDT). Results from the UK (chi(2) = 8.97, P = 0.001, OR = 1.95), but not the Turkish sample (chi(2) = 0.93, P = 0.34) support association and linkage between genetic variation at the DAT1 locus and ADHD. When considered alongside evidence from other published reports, there is only modest evidence for the association, consistent with a very small main effect for the 480-bp allele (chi(2) = 3.45, P = 0.06, OR = 1.15), however we find significant evidence of heterogeneity between the combined dataset (chi(2) = 22.64, df = 8, P = 0.004).

Association between leukocyte count and the presence and extent of coronary atherosclerosis as determined by coronary arteriography

Angiographic evidence of coronary artery disease (CAD) was correlated with leukocyte count (WBC), red cell count (RBC), cigarette smoking, age, sex, and cholesterol and triglyceride concentrations in 573 patients who underwent coronary arteriography and who did not have evidence of infection or recent myocardial infarction. Smokers had a higher WBC (7,449 +/- 1,964 leukocytes/mm3 vs 6,533 +/- 1,557, p = 0.0001) and RBC (4.921 X 10(6) +/- 0.491 X 10(6) erythrocytes/mm3 vs 4.753 X 10(6) +/- 0.480 X 10(6) p = 0.0001) than nonsmokers. Patients with CAD had a higher WBC (7,280 +/- 1,926 vs 6,664 +/- 1,700, p = 0.0005) and RBC (4.903 X 10(6) +/- 0.488 vs 4.777 X 10(6) +/- 0.485 X 10(6), p = 0.0062) than those with normal coronary arteriograms. A positive correlation between WBC and the severity of CAD (sum of arterial diameter narrowing) was noted (r = 0.16, p = 0.0001). Multiple regression showed an independent contribution of WBC in predicting severity of CAD (F = 9.26, p = 0.0025), after accounting for the effects of age, sex, serum cholesterol and triglyceride levels. When smoking was entered into the equation, the contribution of WBC in predicting the severity of angiographic CAD became weaker (F = 4.46, p = 0.035). Similar relations were seen when only smokers were analyzed and when patients with history of remote myocardial infarction were excluded. In nonsmokers these associations became either insignificant or much weaker. Thus, the relation of WBC, and RBC with CAD is mainly due to the elevation of WBC and RBC and the increase of CAD risk induced by cigarette smoking.

Multiple pathways of apoptosis in PC12 cells. CrmA inhibits apoptosis induced by beta-amyloid

Stable transfectants of PC12 cells expressing bcl-2 or crmA were generated and tested for their susceptibility to various apoptotic insults. Bcl-2 expression conferred resistance to apoptosis induced by staurosporine and by oxidative insults including hydrogen peroxide and peroxynitrite, but was less effective in inhibition of activation-induced programmed cell death induced by concanavalin A. Concanavalin A-induced apoptosis was abated, however, in cells expressing very high levels of bcl-2. In contrast, cells expressing crmA were protected from concanavalin A-induced apoptosis, but were as susceptible as control cells to apoptosis induced by staurosporine and oxidative insults. Therefore, at least two apoptotic pathways in PC12 cells can be discerned by their differential sensitivity to blockade by bcl-2 and crmA. The ability of beta-amyloid (Abeta) to induce apoptosis in these cells was assessed. CrmA transfectants were protected from apoptosis induced by Abeta1-42, but only cells expressing very high levels of bcl-2 were similarly protected. These results suggest that the apoptotic pathway activated by Abeta1-42 in PC12 cells can be differentiated from the apoptotic pathway activated by oxidative insults. Gene transfer experiments also demonstrated that expression of crmA in primary cultures of hippocampal neurons is protective against cell death induced by Abeta1-42. Together these results support the hypothesis that Abeta-induced apoptosis occurs through activation-induced programmed cell death.

Psoriatic arthritis imaging: a review of scoring methods

Structural damage assessed on conventional radiographs is an important outcome measure in psoriatic arthritis. This article reviews the available scoring methods. A full description of the methods is given as well as information on various aspects of validity.

Trial of three-day and ten-day courses of amoxycillin in otitis media

A randomised double-blind controlled trial compared three-day and 10-day courses of amoxycillin (25 mg/kg daily) in children with otitis media. Seventeen doctors from five centres admitted 84 children between the ages of 2 and 10 years. Symptoms and signs were measured on admission to the trial, on day 3, and on day 15. Mother's observations were recorded daily for 10 days. Audiograms were performed at four and 12 weeks after the end of the trial. The treatment groups showed little difference in the speed of resolution of symptoms and signs, the numbers of primary treatment failures, or the frequency of recurrent ear infections. There were no complications in either group. Most children with otitis media can probably be successfully and safely treated with no more than a three-day course of amoxycillin providing their progress is reviewed about the fifth or sixth day after treatment started. This policy could save over 1 million pounds annually in antibiotic costs.

Non-cardiac benefits of human recombinant erythropoietin in end stage renal failure and anaemia

Recombinant human erythropoietin (r-HuEpo) is now available to correct the anaemia of end stage renal failure. The clinical consequences of increasing the haemoglobin concentration in children on dialysis are incompletely documented; a placebo controlled study is essential when assessing subjective changes, for example in appetite or other aspects of quality of life. A single blind, placebo controlled crossover study in 11 children with end stage renal failure was performed to assess the clinical benefits resulting from correction of anaemia. Ten of the 11 children completed 36 weeks of the study and seven completed both 24 week limbs. Subcutaneous administration of r-HuEpo twice a week resulted in an increase in haemoglobin concentration, from 73 to 112 g/l. This was associated with an objective improvement in exercise tolerance, and a subjective improvement in physical performance and health, and better school attendance. No consistent effect was seen on appetite, growth, psychosocial functioning, biochemical control, or peritoneal dialysis efficiency. A small but clinically unimportant increase in systolic and diastolic blood pressure was seen in five children. One child on antihypertensive treatment required an increase in dosage during r-HuEpo while another child required a reduction in treatment. These findings, together with the important cardiac benefits previously described during r-HuEpo treatment, support the use of r-HuEpo in all children with end stage renal failure and anaemia.

Interleukin 1-induced pathophysiology: induction of cytokines, development of histopathologic changes, and immunopharmacologic intervention

In this report, we describe a murine system in which treatment with recombinant human interleukin 1 (IL-1) induced an acute lethal state with pathologic changes similar to septic shock at high doses and development of arthritic and other tissue changes following more prolonged treatment with lower doses. We have demonstrated that both recombinant human interleukin 1 alpha and recombinant human interleukin 1 beta could be administered to an endotoxin hyporesponsive strain, C3H/HeJ, and produce these pathologic changes. Induction of tumor necrosis factor (TNF) and colony-stimulating factor activity was noted. The ability to induce these changes was dose and time dependent. Histopathologic changes included lesions in the lung, heart, liver, adrenal glands, intestines, and joints. Neutrophil infiltration was a prominent feature in many organs. Drugs, immunotherapy, or other treatments which have been effective in delaying or preventing a lethal syndrome induced following high dose interleukin 2 therapy were not effective in preventing the interleukin 1-induced lethal syndrome. Interestingly, pretreatment with low nonlethal doses of IL-1 (but not lipopolysaccharides or TNF) could prevent deaths from an LD100 challenge dose of IL-1.

High-resolution three-dimensional imaging of dislocations

Dislocations and their interactions govern the properties of many materials, ranging from work hardening in metals to device pathology in semiconductor laser diodes. However, conventional electron micrographs are simply two-dimensional projections of three-dimensional (3D) structures, and even stereo microscopy cannot reveal the true 3D complexity of defect structures. Here, we describe an electron tomographic method that yields 3D reconstructions of dislocation networks with a spatial resolution three orders of magnitude better than previous work. We illustrate the method's success with a study of dislocations in a GaN epilayer, where dislocation densities of 1010 per square centimeter are common.

Attention deficit hyperactivity disorder (ADHD) and the dopamine D4 receptor gene: evidence of association but no linkage in a UK sample

Recent studies report association and linkage between attention deficit hyperactivity disorder (ADHD) and the 7-repeat allele of a 48 base-pair repeat in the dopamine D4 receptor gene (DRD4). We examined the frequency of this allele in a sample of probands with DSM-IV ADHD using a case-control design, as well as the transmission disequilibrium test (TDT) and haplotype-based haplotype relative risk (HHRR) in the subset of probands with DNA available from both parents. One hundred and thirty-two ADHD probands were compared with 189 controls (chi(2) = 6.17, 1 df, P = 0.01, OR = 1.73, 95% CI = 1.11--2.71). A total of 85 complete trios were available for within-family tests of association and linkage. Fifty-two heterozygous parents carrying one copy of the 7-repeat were informative for the TDT (29 transmitted vs 23 non-transmitted, chi(2) = 0.69). Analysis of the entire sample of 132 probands using TRANSMIT provided no additional evidence for excess transmission of the 7-repeat allele (58 transmitted vs 54 non-transmitted). HHRR gave similar results. We conclude that the case-control findings are likely to be falsely positive, resulting from genetic stratification. However we can not rule out alternative explanations of low statistical power and gene-environment correlation.

Bone and Joint tuberculosis in Greater Manchester 1969-79

The records of 74 patients diagnosed as suffering from tuberculous (TB) bone or joint disease between 1969 and 1979 were analysed retrospectively. Most were resident in the Greater Manchester County. Thirty-eight patients were first-generation immigrants, and teenage males were particularly prominent in this group. In the indigenous patients the diagnosis was often delayed several months or years, and in a number of subjects there was a history of previous bone and joint tuberculosis. There was a wide range of affected sites, especially in the immigrant group, and evidence of nonarticular TB was found in only a minority of patients. Diagnosis is most satisfactorily based on open biopsy and submission of pathological material to culture and histology. British subjects were more likely to have to undergo remedial surgery for the disease, especially when weight bearing joints were involved. Antituberculous chemotherapy should be given for at least 1 year to prevent recurrence of the disease.

Use of quantitative 16S ribosomal DNA detection for diagnosis of central vascular catheter-associated bacterial infection

Many central vascular catheters (CVCs) are removed unnecessarily because current diagnostic methods for CVC-associated infection are unreliable. A quantitative PCR assay using primers and probe targeted to bacterial 16S ribosomal DNA was used to measure the levels of bacterial DNA in blood samples drawn through the CVC in a population of patients receiving intravenous nutrition. Bacterial DNA concentrations were raised in 16 of 16 blood samples taken during episodes of probable bacterial CVC-associated infection. Bacterial DNA concentrations were raised in 4 of 29 episodes in which bacterial CVC-associated infection was unlikely. The use of this technique has the potential to substantially reduce the unnecessary removal of CVCs.

Critical clinical appraisal of the role of ultrasound guided fine needle aspiration cytology in the management of parotid tumours

Objective: Fine needle aspiration cytology is a well established tool for investigating many head and neck conditions. Its application in parotid tumours is, however, controversial. This article is aimed at defining the role of ultrasound guided fine needle aspiration cytology (FNAC) in the diagnostic work up of parotid tumours. The accuracy and utility of FNAC of parotid tumours was also assessed.

Design: Retrospective case note review.

Setting: District general hospital.

Participants: Review of 69 patient records who had parotid surgery under one surgeon’s care (JS). Clinical opinion, FNAC results and final pathology findings were examined.

Main outcome measures: The results of the FNAC were compared to the histopathological diagnosis obtained from the surgical specimen.

Results: Histological evaluation revealed 13 malignant tumours and 56 benign lesions. The overall sensitivity of FNAC was 84.6 per cent and specificity was 96.4 per cent. We noted 11 true positive, 54 true negative, two false negative and two false positive results. Positive predictive value for diagnosing malignancy was 84.6 per cent and negative predictive value for malignancy was 96.4 per cent. The overall accuracy of FNAC of parotids in this study was 94.2 per cent.

Conclusions: FNAC results provide useful preoperative information. FNAC enables more reliable patient counselling and reduces pathological surprises. Pre-operative recognition of malignant tumours may help prepare both the surgeon and patient for an appropriate surgical procedure. Its enhancement of the pre-operative recognition of malignant parotid tumours may alert more stringent attention to the operative margin and hence better tumour clearance. Ultrasound guided FNAC was found to be highly specific for malignancy and its sensitivity for malignancy was good.

Oral health in children with renal disease

Thirty-eight children (aged 2-16 years) attending a regional kidney unit had a full clinical and radiological dental examination. Twenty had previously undergone a renal transplant, 11 had chronic renal failure and 7 had other renal diseases. Periodontal disease was uncommon The presence of gingival hyperplasia (gum overgrowth), as recorded in 22 of the children, did not show any relationship with the use of immunosuppressant therapy. However, gingival overgrowth was so excessive in 2 patients that surgical removal was required. The prevalence of dental caries was low. Enamel defects were common, and of an unusual pattern, with a much higher prevalence of diffuse opacities and enamel hypoplasia than in the normal child population, 83% and 22%, respectively. This increased prevalence is probably due to disordered calcium and phosphate metabolism. The prevalence of these defects may reflect an early onset of renal disease, since there were a number of very young children in the programme. Dental and medical care should be closely integrated for children with renal disease to avoid the undesirable dental sequelae of, in particular, gingival overgrowth, carcinoma and enamel hypoplasia.

The engineering of an interventional MRI with a movable 1.5 Tesla magnet

The engineering of a novel intra-operative MRI system is described. A movable, 1.5 Tesla MRI magnet was placed in a neurosurgical operating room without affecting established neurosurgical procedure. The system allows fast, high-quality MR intra-operative imaging of the brain and spine without the necessity of patient transportation. A neuro-navigational device capable of displaying and updating spatially referenced MR images in the operating room was integrated with the MRI system. Over 100 procedures have been carried out with this system without limiting surgical access and without compromising traditional neurosurgical, nursing or anesthetic techniques. J. Magn. Reson. Imaging 2001;13:78-86.

Haemodialysis and ultrafiltration in babies weighing under 1000 g

Until now it has not be feasible to haemodialyse babies with renal failure who weigh less than 1000 g. Three babies weighing 630, 808, and 1140 g are described. They had multiorgan failure and could not be peritoneally dialysed. They were treated with veno-venous ultrafiltration and haemodialysis using a manual syringe driven technique that required only simple equipment. This method is highly labour intensive, but can provide control of fluid volume and plasma biochemistry in these very sick infants. Their prognosis, however, is determined by the underlying cause of their renal failure, and remains poor.

Haemodialysing infants: theoretical limitations, and single versus double lumen lines

Haemodialysing small infants is difficult because of vascular access limitations. We show that Poiseuille's law (that flow through a tube varies with its radius4) makes it inevitable that the blood flow that can be achieved in smaller patients will fall disproportionately compared to their need for dialysis. Poiseuille's law also predicts that for single and multiple lumen cannulae of the same outside gauge, blood flow through the single lumen will be several times greater. Measurements confirmed this. It is argued that haemodialysis efficiency will therefore be improved by using a single lumen cannula to alternately withdraw and return blood, compared to sampling and returning continuously through a multiple lumen cannula, despite only withdrawing for half the time.