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Featured researches published by Steven Waldek.


The Lancet | 1998

Risk of morbidity from renovascular disease in elderly patients with congestive cardiac failure

P MacDowall; Philip A. Kalra; Donal J. O'Donoghue; Steven Waldek; Hari Mamtora; K Brown

BACKGROUND Renovasular disease commonly affects elderly people. Elderly patients with heart failure are routinely treated with angiotensin-converting-enzyme (ACE) inhibitors, which may increase risk of renal dysfunction. We investigated the frequency of renovascular disease among elderly people with heart failure. METHODS From the local population of Salford, UK, we recruited 86 patients with heart failure with a mean age of 77.5 (SD 5.6) years, who were admitted as acute emergencies or who attended general medical clinics. We selected patients by intention to treat with ACE inhibitors. We used captopril renography to screen for renovascular disease. All patients with abnormal renograms underwent magnetic-resonance angiography of the renal arteries as well as 40% of patients with normal renograms as negative controls. FINDINGS Magnetic-resonance angiography showed severe renovascular disease (>50% renal-artery stenosis or occlusion) in 29 (34%) patients. Captopril renography had an estimated sensitivity of 78.8% (95% CI 72.7-97.8) and specificity of 94.3% (67.6-97.3) for detection of renovascular disease. The estimated positive predictive value of captopril renography was 89.7% and the negative predictive value was 87.5%. Patients with renovascular disease had worse renal function (mean creatinine 201 [SD 56] vs 136 [40] pmol/L, p<0.001), were older (mean age 80.7 [5.6] vs 76.8 [5.3] years, p<0.01), and were more likely than patients without renovascular disease to have peripheral arterial disease. INTERPRETATION Some elderly patients with occult renovascular disease on ACE inhibitors will be at risk of developing uraemia. Renal function should be closely monitored to detect any deterioration early.


Nephrology Dialysis Transplantation | 2008

Nephropathy in males and females with Fabry disease : cross-sectional description of patients before treatment with enzyme replacement therapy

Alberto Ortiz; João Paulo Oliveira; Steven Waldek; David G. Warnock; Bruno Cianciaruso; Christoph Wanner

BACKGROUND Fabry disease, an X-linked genetic disorder with deficient alpha-galactosidase A activity, is characterized by kidney disease and kidney failure. The spectrum of kidney disease has not been well defined, especially in female patients. METHODS We did a cross-sectional retrospective analysis of natural history of glomerular filtration rate (estimated- eGFR), albuminuria and proteinuria in 1262 adult patients (585 males, 677 females) from the Fabry Registry. RESULTS Twenty-eight percent of males (age 20-79 years) and 13% of females (age 20-82 years) had chronic kidney disease (CKD) with eGFR < 60 ml/min/1.73 m(2). Overt proteinuria (>300 mg/24 h) was demonstrated in 43 and 26% of males and females with CKD stage 1, respectively, and the proportions were higher with more severe kidney involvement. However, 11% of males and 28% of females with eGFR < 60 ml/min/1.73 m(2) had proteinuria <300 mg/ 24 h. Of eGFR >/= 60 ml/min/1.73 m(2) patients without overt proteinuria (n = 93), 55% of the males and 35% of the females had albuminuria >30 mg/24 h. Systemic blood pressure was >/=130/80 mmHg in 48% and 67% of patients with eGFR >/= and <60 ml/min/1.73 m(2), respectively, with no significant differences between males and females. Proteinuria values were significantly correlated with systolic blood pressure in both sexes. CONCLUSIONS Kidney involvement in Fabry disease is more prevalent and heterogeneous than previously reported. Proteinuria is an early complication, but may not be overt in patients with advanced kidney disease. This analysis, which includes more females than males, confirms that a significant proportion of females suffer moderate to severe kidney involvement in Fabry disease.


QJM: An International Journal of Medicine | 2010

Fabry disease: a review of current management strategies

Atul Mehta; Michael Beck; F Eyskens; Claudio Feliciani; I Kantola; Uma Ramaswami; Arndt Rolfs; A Rivera; Steven Waldek; Dominique P. Germain

Fabry disease is an X-linked inherited condition due to the absence or reduction of alpha-galactosidase activity in lysosomes, that results in accumulation of globotriaosylceramide (Gb3) and related neutral glycosphingolipids. Manifestations of Fabry disease include serious and progressive impairment of renal and cardiac function. In addition, patients experience pain, gastrointestinal disturbance, transient ischaemic attacks and strokes. Additional effects on the skin, eyes, ears, lungs and bones are often seen. The first symptoms of classic Fabry disease usually appear in childhood. Despite being X-linked, females can suffer the same severity of symptoms as males, and life expectancy is reduced in both females and males. Enzyme replacement therapy (ERT) can stabilize the progression of the disease. The rarity of the classic form of Fabry disease, however, means that there is a need to improve the knowledge and understanding that the majority of physicians have concerning Fabry disease, in order to avoid misdiagnosis and/or delayed diagnosis. This review aims to raise awareness of the signs and symptoms of Fabry disease; to provide a general diagnostic algorithm and to give an overview of the effects of ERT and concomitant treatments. We highlight a need to develop comprehensive international guidelines to optimize ERT and adjunctive therapy in patients with Fabry disease, including females and children.


Health Technology Assessment | 2012

The effectiveness and cost-effectiveness of enzyme and substrate replacement therapies: a longitudinal cohort study of people with lysosomal storage disorders.

Katrina Wyatt; William Henley; Lindsey Anderson; Rob Anderson; Vasilis Nikolaou; Ken Stein; L Klinger; Derralynn Hughes; Steven Waldek; Robin H. Lachmann; Atul Mehta; Ashok Vellodi; Stuart Logan

OBJECTIVES To determine natural history and estimate effectiveness and cost of enzyme replacement therapy (ERT) and substrate replacement therapy (SRT) for patients with Gaucher disease, Fabry disease, mucopolysaccharidosis type I (MPS I), mucopolysaccharidosis type II (MPS II), Pompe disease and Niemann-Pick type C (NPC) disease. DESIGN Cohort study including prospective and retrospective clinical- and patient-reported data. Age- and gender-adjusted treatment effects were estimated using generalised linear mixed models. Treated patients contributed data before and during treatment. Untreated patients contributed natural history data. SETTING National Specialised Commissioning Group-designated lysosomal storage disorder (LSD) treatment centres in England. PARTICIPANTS Consenting adults and children with a diagnosis of Gaucher disease (n = 272), Fabry disease (n = 499), MPS I (n = 126), MPS II (n = 58), NPC (n = 58) or Pompe disease (n = 93) who had attended a treatment centre in England. INTERVENTIONS ERT and SRT. MAIN OUTCOME MEASURES Clinical outcomes chosen by clinicians to reflect disease progression for each disorder; patient-reported quality-of-life (QoL) data; cost of treatment and patient-reported service-use data; numbers of hospitalisations, outpatient and general practitioner appointments; medication use; data pertaining to associated family/carer costs and QoL impacts. RESULTS Seven hundred and eleven adults and children were recruited. In those with Gaucher disease (n = 175) ERT was associated with improved platelet count, haemoglobin, liver function and reduced risk of enlarged liver or spleen. No association was found between ERT and QoL. In patients with Fabry disease (n = 311) increased time on ERT was associated with small decreases in left ventricular mass and improved glomerular filtration rate, but not with changes in risk of stroke/transient ischaemic attacks or the need for a hearing aid. There was a statistically significant association between duration of ERT use and worsening QoL and fatigue scores. We found no statistical difference in estimates of treatment effectiveness between the two preparations, agalsidase beta (Fabrazyme(®), Genzyme) (n = 127) and agalsidase alpha (Replagal(®), Shire HGT) (n = 91), licensed for this condition. In Pompe disease (n = 77) our data provide some evidence of a beneficial effect on muscle strength and mobility as measured by a 6-minute walk test in adult-onset patients; there were insufficient data from infantile-onset Pompe patients to estimate associations between ERT and outcome. Among subjects with MPS I (n = 68), 42 of the 43 patients with MPS I subtype Hurlers disease had undergone a bone marrow transplant. No significant associations were found between ERT and any outcome measure for the MPS I subtype Scheie disease and heparan sulphate patients. An association between duration of ERT and growth in children was the only statistically significant finding among patients with MPS II (n = 39). There were insufficient data for patients with NPC disease to draw any conclusions regarding the effectiveness of SRT. The current annual cost to the NHS of the different ERTs means that between 3.6 and 17.9 discounted quality-adjusted life-years (QALYs) for adult patients and between 2.6 and 10.5 discounted QALYs for child patients would need to be generated for each year of being on treatment for ERTs to be considered cost-effective by conventional criteria. CONCLUSIONS These data provide further evidence on the effectiveness of ERT in people with LSDs. However, the results need to be interpreted in light of the fact that the data are observational and the relative lack of power due to the small numbers of patients with MPS I, MPS II, Pompe disease and NPC disease. Future work should aim to effectively address the unanswered questions and this will require agreement on a common set of outcome measures and their consistent collection across all treatment centres. FUNDING This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 16, No. 39. See the HTA programme website for further project information.


Postgraduate Medical Journal | 2006

Prevalence of hypogonadism in male patients with renal failure

F Albaaj; M Sivalingham; P Haynes; G McKinnon; Robert N. Foley; Steven Waldek; Donal J. O'Donoghue; Philip A. Kalra

Background: Hypogonadism in men may be secondary to renal failure and is well recognised in patients with end-stage renal disease. It is thought to contribute to the sexual dysfunction and osteoporosis experienced by these patients. However, the association between hypogonadism and lesser degrees of renal dysfunction is not well characterised. Methods: The gonadal status of 214 male patients (mean age 56 (SD 18) years) attending a renal centre was studied; 62 of them were receiving haemodialysis and 22 continuous ambulatory peritoneal dialysis for end-stage renal disease, whereas 34 patients had functioning renal transplants and 96 patients were in the low-clearance phase. Non-fasting plasma was analysed for testosterone, follicle-stimulating hormone, luteinising hormone, sex hormone-binding globulin, parathyroid hormone and haemoglobin. Creatinine clearance was estimated in patients not on dialysis, and Kt/V and urea reduction ratio were assessed in patients on dialysis. Testosterone concentrations were classified as normal (>14 nmol/l), low-normal (10–14 nmol/l) or low (<10 nmol/l). Results: 56 (26.2%) patients had significantly low testosterone levels and another 65 (30.3%) had low-normal levels. No significant changes were seen in sex hormone-binding globulin or gonadotrophin levels. Gonadal status was not correlated with haemoglobin level, parathyroid hormone level, creatinine clearance, or dialysis duration or adequacy. Conclusion: Over half of patients with renal failure, even in the pre-dialysis phase, have low or low-normal levels of testosterone, which may be a potentially reversible risk factor for osteoporosis and sexual dysfunction. These patients may be candidates for testosterone-replacement therapy, which has been shown to improve bone mineral-density and libido in men with low and low-normal testosterone levels.


JIMD reports | 2012

Recommendations on Reintroduction of Agalsidase Beta for Patients with Fabry Disease in Europe, Following a Period of Shortage

Gabor E. Linthorst; Alessandro P. Burlina; Franco Cecchi; Timothy M. Cox; Janice M. Fletcher; Ulla Feldt-Rasmussen; Roberto Giugliani; Carla E. M. Hollak; Gunnar Houge; Derralynn Hughes; Iikka Kantola; Robin H. Lachmann; Mónica Luján López; Alberto Ortiz; Rossella Parini; Alberto Rivera; Arndt Rolfs; Uma Ramaswami; Einar Svarstad; Camilla Tøndel; Anna Tylki-Szymańska; Bojan Vujkovac; Steven Waldek; Michael West; Frank Weidemann; Atul Mehta

The interruption of the manufacturing process of agalsidase beta has led to a worldwide shortage of this drug. In the EU, nearly all patients initially reduced their agalsidase beta dose, and many of these switched to agalsidase alfa (Replagal Shire HGT). The clinical consequences of this period of drug shortage need to be further evaluated. A gradual increase of agalsidase beta supply is now expected. This implies that patients could resume or even commence agalsidase beta treatment. Guidance for prioritization of patients is needed to support equitable distribution of agalsidase beta to EU member states. To achieve this, in absence of level I clinical evidence, a draft consensus proposal was initiated and distributed. No full consensus was achieved, as there is disagreement regarding the indications for switching patients from agalsidase alfa to agalsidase beta. Some physicians support the concept that the 1.0 mg/kg EOW dose of agalsidase beta is more effective than agalsidase alfa at 0.2 mg/kg EOW, while others believe that at recommended dose, the preparations are equivalent. In light of these difficulties and the uncertainties with respect to supply of agalsidase beta, recommendations were agreed upon by a subgroup of physicians. These current recommendations focus on prioritization of criteria indicative of disease progression.


American Journal of Kidney Diseases | 2002

A prospective study of the determinants of renal functional outcome and mortality in atherosclerotic renovascular disease

Julian Wright; Ala'a E. Shurrab; Ching Cheung; Steven Waldek; Donal J. O'Donoghue; Robert N. Foley; Hari Mamtora; Philip A. Kalra


Nephrology Dialysis Transplantation | 2001

Primary bilateral T‐cell renal lymphoma presenting with sudden loss of renal function

Edmond O'Riordan; Roy Reeve; John B. Houghton; Donal J. O'Donoghue; Steven Waldek


Nephrology Dialysis Transplantation | 1995

A febrile patient with a renal space-occupying lesion evolving into renal abscess: acute focal bacterial nephritis

Grahame Wood; Philip A. Kalra; Hari Mamtora; Steven Waldek; Donal O’Donoghue


Nephrology Dialysis Transplantation | 1992

Successful control of heavy proteinuria and return of renal function after bilateral renal artery embolization in focal segmental glomerulosclerosis

Q. Aziz; Philip A. Kalra; Hari Mamtora; Steven Waldek

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Atul Mehta

Royal Free London NHS Foundation Trust

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Philip A. Kalra

Royal University Hospital

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Alberto Ortiz

Autonomous University of Madrid

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