Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Jan Dudley is active.

Publication


Featured researches published by Jan Dudley.


Journal of The American Society of Nephrology | 2014

Initial Steroid Sensitivity in Children with Steroid-Resistant Nephrotic Syndrome Predicts Post-Transplant Recurrence

Wen Y. Ding; Ania Koziell; Hugh J. McCarthy; Agnieszka Bierzynska; Murali K. Bhagavatula; Jan Dudley; Carol Inward; Richard J M Coward; Jane Tizard; Christopher Reid; Corinne Antignac; Olivia Boyer; Moin A. Saleem

Of children with idiopathic nephrotic syndrome, 10%-20% fail to respond to steroids or develop secondary steroid resistance (termed initial steroid sensitivity) and the majority progress to transplantation. Although 30%-50% of these patients suffer disease recurrence after transplantation, with poor long-term outcome, no reliable indicator of recurrence has yet been identified. Notably, the incidence of recurrence after transplantation appears reduced in patients with steroid-resistant nephrotic syndrome (SRNS) due to monogenic disorders. We reviewed 150 transplanted patients with SRNS to identify biomarkers that consistently predict outcome of SRNS after transplantation. In all, 25 children had genetic or familial SRNS and did not experience post-transplant recurrence. We reviewed phenotypic factors, including initial steroid sensitivity, donor type, age, ethnicity, time to ESRD, and time on dialysis, in the remaining 125 children. Of these patients, 57 (45.6%) developed post-transplant recurrence; 26 of 28 (92.9%) patients with initial steroid sensitivity recurred after transplantation, whereas only 26 of 86 (30.2%) patients resistant from the outset recurred (odds ratio, 30; 95% confidence interval, 6.62 to 135.86; P<0.001). We were unable to determine recurrence in two patients (one with initial steroid sensitivity), and nine patients did not receive initial steroids. Our data show that initial steroid sensitivity is highly predictive of post-transplant disease recurrence in this pediatric patient population. Because a pathogenic circulating permeability factor in nephrotic syndrome remains to be confirmed, we propose initial steroid sensitivity as a surrogate marker for post-transplant recurrence.


Archives of Disease in Childhood | 2013

Randomised, double-blind, placebo-controlled trial to determine whether steroids reduce the incidence and severity of nephropathy in Henoch-Schönlein Purpura (HSP)

Jan Dudley; Graham Smith; Anne Llewelyn-Edwards; Kate M. Bayliss; Katie Pike; Jane Tizard

Background The long-term prognosis of Henoch-Schönlein Purpura (HSP) is predominantly determined by the extent of renal involvement. There is no consensus as to whether treatment with prednisolone at presentation can prevent or ameliorate the progression of nephropathy in HSP. Methods Children under 18 years of age with new-onset HSP were randomly assigned to receive prednisolone or placebo for 14 days. The primary outcomes were (a) the presence of proteinuria at 12 months (defined as urine protein : creatinine ratio (UP : UC) >20 mg/mmol) and (b) the need for additional treatment (defined as the presence of hypertension requiring treatment or renal biopsy anomalies or the need for treatment of renal disease) during the 12 month study period. Results 352 children were randomised. Of those patients with laboratory UP : UC results available at 12 months, 18/123 (15%) patients on prednisolone and 13/124 (10%) patients on placebo had UP : UC >20 mg/mmol. There was no significant difference in the proportion of patients with UP : UC >20 mg/mmol at 12 months between the treatment groups (OR (prednisolone/placebo)=1.46, 95% CI 0.68 to 3.14, n=247), even after adjusting for baseline proteinuria and medications known to affect proteinuria (adjusted OR=1.29, 95% CI 0.58 to 2.82, n=247). Similarly, there was no significant difference in the time needed for additional treatment between the two groups (hazard ratio (HR) (prednisolone/placebo)=0.53, 95% CI 0.18 to 1.59, n=323). Conclusions This is the largest trial of the role of steroids in children with HSP. We found no evidence to suggest that early treatment with prednisolone reduces the prevalence of proteinuria 12 months after disease onset in children with HSP. Trial registration Number ISRCTN71445600


Nephrology Dialysis Transplantation | 2013

Impact of graft loss among kidney diseases with a high risk of post-transplant recurrence in the paediatric population

Karlijn J. van Stralen; Enrico Verrina; Mirco Belingheri; Jan Dudley; Jiří Dušek; Ryszard Grenda; Marie Alice Macher; Zvonimir Puretić; Jacek Rubic; Sarunas Rudaitis; Christoph Rudin; Franz Schaefer; Kitty J. Jager

BACKGROUND Some kidney diseases tend to recur in the renal allograft after transplantation. We studied the risk of graft loss among primary renal diseases known for their high risk of recurrence and compared it with that of patients with hypoplasia and/or dysplasia. METHODS Within the European Society of Paediatric Nephrology and European Renal Association and European Dialysis and Transplant Association (ESPN/ERA-EDTA) registry, we studied children from 33 countries who received a kidney transplant before the age of 20 between 1990 and 2009. Patients were censored after 5 years of follow-up and cumulative incidence competing risk analysis was used to calculate survival curves. RESULTS Patients with focal and segmental glomerulosclerosis (FSGS), haemolytic uraemic syndrome (HUS), membranoproliferative glomerulonephritis Type I or II (MPGN), IgA nephropathy or Henoch Schönlein Purpura (HSP/IgA) or systemic lupus erythomatosus (SLE) underwent pre-emptive transplantation significantly less often than patients with hypoplasia and/or dysplasia. The rate of living donation was lower among patients with FSGS and SLE than in patients with hypoplasia and/or dysplasia. In comparison with hypoplasia and/or dysplasia patients with a risk of 14.4%, the 5-year risk of graft loss was significantly increased in patients with FSGS (25.7%) and MPGN (32.4%) while it was not significantly increased in children with HUS (18.9%), HSP/IgA (16.3%) or SLE (20.3%). One-year graft survival strongly improved among HUS patients from 17.1% in 1995-1999 to 3.6% in 2005-2009 and was not accompanied by a decrease in the number of transplantations. CONCLUSION The risk of graft loss is increased among specific causes of renal failure with a high risk of post-transplant recurrence. It seems likely that, due to anticipation of such risk, physicians perform less pre-emptive transplantation and provide fewer grafts from living related donors in patients with these conditions. Improved risk stratification by physicians, resulting in the identification of patients with HUS at higher or lower risk of recurrence, might explain the much improved graft survival rates.


Annals of Family Medicine | 2016

Improving the Diagnosis and Treatment of Urinary Tract Infection in Young Children in Primary Care: Results from the DUTY Prospective Diagnostic Cohort Study

Alastair D Hay; Jonathan A C Sterne; Kerenza Hood; Paul Little; Brendan Delaney; William Hollingworth; Mandy Wootton; Robin Howe; Alasdair P. MacGowan; Michael T. Lawton; John Busby; Timothy Pickles; Kate Birnie; Kathryn O’Brien; Cherry-Ann Waldron; Jan Dudley; Judith van der Voort; Harriet Downing; Emma Thomas-Jones; Kim Harman; Catherine Lisles; Kate Rumsby; Stevo Durbaba; Penny Whiting; Christopher C. Butler

PURPOSE Up to 50% of urinary tract infections (UTIs) in young children are missed in primary care. Urine culture is essential for diagnosis, but urine collection is often difficult. Our aim was to derive and internally validate a 2-step clinical rule using (1) symptoms and signs to select children for urine collection; and (2) symptoms, signs, and dipstick testing to guide antibiotic treatment. METHODS We recruited acutely unwell children aged under 5 years from 233 primary care sites across England and Wales. Index tests were parent-reported symptoms, clinician-reported signs, urine dipstick results, and clinician opinion of UTI likelihood (clinical diagnosis before dipstick and culture). The reference standard was microbiologically confirmed UTI cultured from a clean-catch urine sample. We calculated sensitivity, specificity, and area under the receiver operator characteristic (AUROC) curve of coefficient-based (graded severity) and points-based (dichotomized) symptom/sign logistic regression models, and we then internally validated the AUROC using bootstrapping. RESULTS Three thousand thirty-six children provided urine samples, and culture results were available for 2,740 (90%). Of these results, 60 (2.2%) were positive: the clinical diagnosis was 46.6% sensitive, with an AUROC of 0.77. Previous UTI, increasing pain/crying on passing urine, increasingly smelly urine, absence of severe cough, increasing clinician impression of severe illness, abdominal tenderness on examination, and normal findings on ear examination were associated with UTI. The validated coefficient- and points-based model AUROCs were 0.87 and 0.86, respectively, increasing to 0.90 and 0.90, respectively, by adding dipstick nitrites, leukocytes, and blood. CONCLUSIONS A clinical rule based on symptoms and signs is superior to clinician diagnosis and performs well for identifying young children for noninvasive urine sampling. Dipstick results add further diagnostic value for empiric antibiotic treatment.


British Journal of General Practice | 2015

Childhood urinary tract infection in primary care: a prospective observational study of prevalence, diagnosis, treatment, and recovery

Christopher Collett Butler; Kathryn O’Brien; Timothy Pickles; Kerenza Hood; Mandy Wootton; Robin Howe; Cherry-Ann Waldron; Emma Thomas-Jones; William Hollingworth; Paul Little; Judith van der Voort; Jan Dudley; Kate Rumsby; Harriet Downing; Kim Harman; Alastair D Hay

BACKGROUND The prevalence of targeted and serendipitous treatment for, and associated recovery from, urinary tract infection (UTI) in pre-school children is unknown. AIM To determine the frequency and suspicion of UTI in children who are acutely ill, along with details of antibiotic prescribing, its appropriateness, and whether that appropriateness impacted on symptom improvement and recovery. DESIGN AND SETTING Prospective observational cohort study in primary care sites in urban and rural areas in England and Wales. METHOD Systematic urine sampling from children aged <5 years presenting in primary care with acute illness with culture in NHS laboratories. RESULTS Of 6079 childrens urine samples, 339 (5.6%) met laboratory criteria for UTI and 162 (47.9%) were prescribed antibiotics at the initial consultation. In total, 576/7101 (8.1%) children were suspected of having a UTI prior to urine sampling, including 107 of the 338 with a UTI (clinician sensitivity 31.7%). Children with a laboratory-diagnosed UTI were more likely to be prescribed antibiotics when UTI was clinically suspected than when it was not (86.0% versus 30.3%, P<0.001). Of 231 children with unsuspected UTI, 70 (30.3%) received serendipitous antibiotics (that is, antibiotics prescribed for a different reason). Overall, 176 (52.1%) children with confirmed UTI did not receive any initial antibiotic. Organism sensitivity to the prescribed antibiotic was higher when UTI was suspected than when treated serendipitously (77.1% versus 26.0%; P<0.001). Children with UTI prescribed appropriate antibiotics at the initial consultation improved a little sooner than those with a UTI who were not prescribed appropriate antibiotics initially (3.5 days versus 4.0 days; P = 0.005). CONCLUSION Over half of children with UTI on culture were not prescribed antibiotics at first presentation. Serendipitous UTI treatment was relatively common, but often inappropriate to the organisms sensitivity. Methods for improved targeting of antibiotic treatment in children who are acutely unwell are urgently needed.


Archives of Disease in Childhood | 2016

Hypertension in autosomal dominant polycystic kidney disease: a meta-analysis

Matko Marlais; Oliver Cuthell; Dean Langan; Jan Dudley; Manish D. Sinha; Paul J.D. Winyard

Context Autosomal dominant polycystic kidney disease (ADPKD) is a common disorder that can cause hypertension during childhood, but the true prevalence of hypertension during childhood is not known. Objective We undertook a systematic review and meta-analysis to determine the prevalence of hypertension in children with ADPKD. Data sources Systematic review of articles published between 1980 and 2015 in MEDLINE and EMBASE. Study selection Studies selected by two authors independently if reporting data on prevalence of hypertension in children and young persons aged <21 years with a diagnosis of ADPKD. Observational series were included with study populations of >15 children. Articles were excluded if inadequate diagnostic criteria for hypertension were used. Studies with selection bias were included but analysed separately. Data extraction Data extracted on prevalence of hypertension, proteinuria and reduced renal function using standardised form. Meta-analysis was performed to calculate weighted mean prevalence. Results 903 articles were retrieved from our search; 14 studies met the inclusion criteria: 1 prospective randomised controlled trial; 8 prospective observational studies; and 5 retrospective cross-sectional studies. From 928 children with clinically confirmed ADPKD, 20% (95% CI 15% to 27%) were hypertensive. The estimated prevalence of proteinuria in children with ADPKD is 20% (8 studies; 95% CI 9% to 40%) while reduced renal function occurred in 8% (5 studies; 95% CI 2% to 26%). Limitations Studies showed a high degree of methodological heterogeneity (I2=73.4%, τ2=0.3408, p<0.0001). Most studies did not use ambulatory blood pressure (BP) monitoring to diagnose hypertension. Conclusions In this meta-analysis we estimate 20% of children with ADPKD have hypertension. In the population, many children with ADPKD are not under regular follow-up and remain undiagnosed. We recommend that all children at risk of ADPKD have regular BP measurement.


Acta Paediatrica | 2015

Implementation of NICE guidance on urinary tract infections in children in primary and secondary care.

Caroline Platt; James Larcombe; Jan Dudley; Cliodna McNulty; Jaydip Banerjee; Gita Gyoffry; Katie Pike; Lyda Jadresic

To audit compliance with the 2007 National Institute of Clinical Excellence guidelines on the management of urinary tract infection in children under the age of 16 years across primary and secondary care services in England.


Pediatric Nephrology | 2014

Renal consequences of parenteral nutrition

Jan Dudley; Rebekah Rogers; Laura Sealy

Parenteral nutrition (PN) can be described as the “Intravenous administration of nutrients necessary to sustain life in those who would otherwise have died or suffered serious disease”. PN is indicated in children who cannot be fully fed by the oral or intestinal route, usually as a result of intestinal failure. Intradialytic parenteral nutrition (IDPN) is rarely indicated in children on dialysis and does not confer a benefit over enteral supplements in the compliant patient with adequate intestinal function. Renal and metabolic consequences of PN are potentially life-threatening and include disorders of glucose homeostasis, acid-base and fluid and electrolyte disturbances, nephrolithiasis, impaired renal function and metabolic bone disease. Many of these complications are avoidable. Adequate clinical and biochemical assessment and monitoring of children receiving PN by a multidisciplinary nutrition support team is recommended to mitigate against the risks of these complications.


Archives of Disease in Childhood | 2015

Clinical audit: Still an important tool for improving healthcare

James Y. Paton; Rita Ranmal; Jan Dudley

The use of data to challenge and improve healthcare has a long and distinguished history but has often failed to bring about expected improvements. It has never become fully embedded in clinical practice, probably because data alone are insufficient to drive change. There is now a greater appreciation that changing and improving healthcare requires changing behaviours. Clinical audit remains one of the important tools that can be used to facilitate such change.


Health Technology Assessment | 2016

Immunosuppressive therapy for kidney transplantation in children and adolescents: systematic review and economic evaluation.

Marcela Haasova; Tristan Snowsill; Tracey Jones-Hughes; Louise Crathorne; Chris Cooper; Jo Varley-Campbell; Ruben Mujica-Mota; Helen Coelho; Nicola Huxley; Jenny Lowe; Jan Dudley; Stephen Marks; Chris Hyde; Mary Bond; Rob Anderson

BACKGROUND End-stage renal disease is a long-term irreversible decline in kidney function requiring kidney transplantation, haemodialysis or peritoneal dialysis. The preferred option is kidney transplantation followed by induction and maintenance immunosuppressive therapy to reduce the risk of kidney rejection and prolong graft survival. OBJECTIVES To systematically review and update the evidence for the clinical effectiveness and cost-effectiveness of basiliximab (BAS) (Simulect,(®) Novartis Pharmaceuticals) and rabbit antihuman thymocyte immunoglobulin (Thymoglobuline,(®) Sanofi) as induction therapy and immediate-release tacrolimus [Adoport(®) (Sandoz); Capexion(®) (Mylan); Modigraf(®) (Astellas Pharma); Perixis(®) (Accord Healthcare); Prograf(®) (Astellas Pharma); Tacni(®) (Teva); Vivadex(®) (Dexcel Pharma)], prolonged-release tacrolimus (Advagraf,(®) Astellas Pharma); belatacept (BEL) (Nulojix,(®) Bristol-Myers Squibb), mycophenolate mofetil (MMF) [Arzip(®) (Zentiva), CellCept(®) (Roche Products), Myfenax(®) (Teva), generic MMF is manufactured by Accord Healthcare, Actavis, Arrow Pharmaceuticals, Dr Reddys Laboratories, Mylan, Sandoz and Wockhardt], mycophenolate sodium, sirolimus (Rapamune,(®) Pfizer) and everolimus (Certican,(®) Novartis Pharmaceuticals) as maintenance therapy in children and adolescents undergoing renal transplantation. DATA SOURCES Clinical effectiveness searches were conducted to 7 January 2015 in MEDLINE (via Ovid), EMBASE (via Ovid), Cochrane Central Register of Controlled Trials (via Wiley Online Library) and Web of Science [via Institute for Scientific Information (ISI)], Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and Health Technology Assessment (HTA) (The Cochrane Library via Wiley Online Library) and Health Management Information Consortium (via Ovid). Cost-effectiveness searches were conducted to 15 January 2015 using a costs or economic literature search filter in MEDLINE (via Ovid), EMBASE (via Ovid), NHS Economic Evaluation Databases (via Wiley Online Library), Web of Science (via ISI), Health Economic Evaluations Database (via Wiley Online Library) and EconLit (via EBSCOhost). REVIEW METHODS Titles and abstracts were screened according to predefined inclusion criteria, as were full texts of identified studies. Included studies were extracted and quality appraised. Data were meta-analysed when appropriate. A new discrete time state transition economic model (semi-Markov) was developed; graft function, and incidences of acute rejection and new-onset diabetes mellitus were used to extrapolate graft survival. Recipients were assumed to be in one of three health states: functioning graft, graft loss or death. RESULTS Three randomised controlled trials (RCTs) and four non-RCTs were included. The RCTs only evaluated BAS and tacrolimus (TAC). No statistically significant differences in key outcomes were found between BAS and placebo/no induction. Statistically significantly higher graft function (p < 0.01) and less biopsy-proven acute rejection (odds ratio 0.29, 95% confidence interval 0.15 to 0.57) was found between TAC and ciclosporin (CSA). Only one cost-effectiveness study was identified, which informed NICE guidance TA99. BAS [with TAC and azathioprine (AZA)] was predicted to be cost-effective at £20,000-30,000 per quality-adjusted life year (QALY) versus no induction (BAS was dominant). BAS (with CSA and MMF) was not predicted to be cost-effective at £20,000-30,000 per QALY versus no induction (BAS was dominated). TAC (with AZA) was predicted to be cost-effective at £20,000-30,000 per QALY versus CSA (TAC was dominant). A model based on adult evidence suggests that at a cost-effectiveness threshold of £20,000-30,000 per QALY, BAS and TAC are cost-effective in all considered combinations; MMF was also cost-effective with CSA but not TAC. LIMITATIONS The RCT evidence is very limited; analyses comparing all interventions need to rely on adult evidence. CONCLUSIONS TAC is likely to be cost-effective (vs. CSA, in combination with AZA) at £20,000-30,000 per QALY. Analysis based on one RCT found BAS to be dominant, but analysis based on another RCT found BAS to be dominated. BAS plus TAC and AZA was predicted to be cost-effective at £20,000-30,000 per QALY when all regimens were compared using extrapolated adult evidence. High-quality primary effectiveness research is needed. The UK Renal Registry could form the basis for a prospective primary study. STUDY REGISTRATION This study is registered as PROSPERO CRD42014013544. FUNDING The National Institute for Health Research HTA programme.

Collaboration


Dive into the Jan Dudley's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar

Kate Rumsby

University of Southampton

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Paul Little

University of Southampton

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Michael T. Lawton

Barrow Neurological Institute

View shared research outputs
Researchain Logo
Decentralizing Knowledge