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Dive into the research topics where Geoff Koffman is active.

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Featured researches published by Geoff Koffman.


Pediatric Nephrology | 1990

Recurrence of focal segmental glomerulosclerosis in transplanted kidneys: Analysis of incidence and risk factors in 59 allografts

Prabha Senggutuvan; J. Stewart Cameron; R. Barrie Hartley; Sue Rigden; Cyril Chantler; G B Haycock; D. Gwyn Williams; C.S. Ogg; Geoff Koffman

Fifty-nine allografts were placed in 43 patients with renal failure from focal segmental glomerulosclerosis (FSGS): 27 allografts were put into 16 children aged less than 15 years, and 32 allografts into 27 adolescents and adults. Recurrence of FSGS was noted histologically in 13 allografts, 10 in 8 children and 3 in adults. None of the 9 children and 24 adults who never developed an allograft nephrotic syndrome showed FSGS in their allograft biopsies. The age of onset was a strong risk factor for recurrence: recurrent FSGS developed in 8 of 16 children (50%) but only in 11% of adolescents and adults (3 of 27 patients). Although the time from apparent onset to renal replacement treatment was shorter in those with recurrence than those without in the children, there was no difference in the time spent on dialysis prior to transplantation. Mesangial prominence was observed in the original biopsy in 12 of 13 patients with recurrence, and recurrence rate was similar in living and cadaver donor allografts; class I MHC matching was similar in those with and without recurrence. Three allografts treated with cyclosporin A as well as 9 with azathioprine showed recurrence. Of 9 second or subsequent allografts placed in those with recurrence in the first allograft, only 3 showed further recurence. rence. In 3 re-grafted after 13, 11 and 5 years, normal function was seen.


BJUI | 2005

Multimodal management of urolithiasis in renal transplantation.

Ben Challacombe; Prokar Dasgupta; R. C. Tiptaft; Jonathan Glass; Geoff Koffman; David Goldsmith; Mohammed Shamim Khan

To report the largest single series of renal transplant patients (adults and children) with urolithiasis, assess the risk factors associated with urolithiasis in renal transplant recipients, and report the outcome of the multimodal management by endourological and open procedures.


BJUI | 2013

Incidental renal stones in potential live kidney donors: prevalence, assessment and donation, including role of ex vivo ureteroscopy

Jonathon Olsburgh; Kay Thomas; Kathie Wong; Matthew Bultitude; Jonathan Glass; Giles Rottenberg; Lisa Silas; Rachel Hilton; Geoff Koffman

Previously, donors with asymptomatic stones found incidentally on CT were not considered ideal donor candidates because of the presumed risk of morbidity to both the donor and recipient. Increasingly, studies show that these risks are low. This study aims to evaluate the long‐term safety of using ex vivo ureteroscopy to remove the stones from the donor kidney on the bench before donation. Outcomes so far suggest that this technique can safely render a kidney stone‐free before transplantation. This has led to 20 more transplants in our institution than would otherwise be possible.


Transplantation | 2010

Challenges facing renal transplantation in pediatric patients with lower urinary tract dysfunction.

Paul Riley; Stephen D. Marks; Divyesh Desai; Imran Mushtaq; Geoff Koffman; Nizam Mamode

In pediatric patients with end-stage renal disease, renal transplantation is the established therapy of choice. The commonest cause is a congenital abnormality of the kidneys and urinary tract, often associated with lower urinary tract dysfunction (LUTD). Historically, such patients were denied transplantation, but it is now widely accepted that transplant outcomes comparable with the non-LUTD population are achievable. Nonetheless, the optimal management of pediatric end-stage renal disease patients with LUTD is unclear, with no guidelines to distinguish between the need for conservative management or surgical reconstruction of the lower urinary tract. Furthermore, the most appropriate surgical procedure and optimal timing of surgical intervention is far from clear. In this review, we outline common conditions that produce LUTD in children; discuss difficulties encountered in assessing the need for surgical treatment; provide an overview of the surgical procedures available; and consider the evidence for and against surgical intervention before, during, and after renal transplantation.


Annals of The Royal College of Surgeons of England | 2008

Living-Unrelated Donor Renal Transplantation: An Alternative to Living-Related Donor Transplantation?

Nadeem Ahmad; Kamran Ahmed; Mohammad Shamim Khan; Francis Calder; Nizam Mamode; John Taylor; Geoff Koffman

INTRODUCTION An increasing number of living-unrelated, kidney donor transplants are being performed in our unit. We present a comparison of living-unrelated (LURD) and living-related donor (LRD) renal transplant outcomes and analyse influencing factors. PATIENTS AND METHODS We retrospectively analysed the outcome of all living-donor renal transplants performed at our centre from 1993 to 2004. The parameters studied included patient and graft survival, functioning status of grafts (determined by estimated GFR) at last follow-up and any rejection episodes. Multivariate analysis was performed for recipient and donor age, ethnicity, HLA matching and re-transplants. RESULTS A total of 322 live donor kidney transplants (LRD, n = 261; LURD, n = 61) were carried out over this period. Mean recipient age was 28 +/- 16 years in the LRD group and 48 +/- 12 years in LURD, while mean age of the donors was 43 +/- 11 years and 48 +/- 10 years, respectively. Caucasians constituted 80% of all the living donors. Amongst LRD, parents were the commonest (58%) donors followed by siblings (35%). In LURD, 80% were spouses. A total of 33 grafts failed, 30 in LRD (11%) and 3 in LURD (5%). Thirteen patients died, 11 (4.2%) in LRD (7 with functioning graft) and 2 (3.3%) in LURD (1 with functioning graft). Acute rejections occurred in 41% recipients in LRD and 35% in LURD (P = 0.37). Estimated GFR was lower in LURD than in LRD (49 +/- 14 versus 59 +/- 29 ml/min/1.73 m(2); P = 0.032). One- and 3-year patient survival for LRD and LURD was 98.7% and 96.3% and 97.7% and 95%, respectively (P = 0.75). One- and 3-year graft survival was equivalent at 94.8% and 92.3% for LRD, and 98.4% and 93.7% for LURD, respectively (P = 0.18). CONCLUSIONS Outcome of LRD and LURD is comparable in terms of patient and graft survival, acute rejection rate and estimated GFR despite differences in demographics, HLA matching and re-transplants of recipients.


International Journal of Clinical Practice | 2005

Follow‐up of polytetrafluoroethylene arteriovenous fistulae for haemodialysis

B Modarai; Prokar Dasgupta; J Taylor; Geoff Koffman; M.S. Khan

The polytetrafluoroethylene (PTFE) arteriovenous fistula allows vascular access for haemodialysis where a primary fistula or brachio‐basilic vein transposition is not possible. We report patency rates and complications associated with these prosthetic grafts.


Nephrology Dialysis Transplantation | 2012

Outcome of surgical complications following simultaneous pancreas–kidney transplantation

Neal Banga; Vassilis G. Hadjianastassiou; Nizam Mamode; Francis Calder; Jonathon Olsburgh; Martin Drage; Cinzia Sammartino; Geoff Koffman; John Taylor

BACKGROUND Simultaneous pancreas-kidney (SPK) transplantation carries a higher risk of surgical complications than kidney transplantation alone. We aimed to establish the incidence of surgical complications after SPK transplantation and determine the effect on graft and patient survival. METHODS Outcomes of all SPK transplants performed at our centre were compared between patients who experienced a surgical complication (SC group) and those who did not (NSC group). RESULTS Our centre performed 193 SPK transplants in a 15-year period; 44 patients (23%) experienced a surgical complication. One-year and 5-year pancreatic graft survival was 89 and 80%, respectively; this was lower in the SC group. There was no significant difference in patient or kidney graft survival between the SC and NSC groups at 5 years (92 and 83%, respectively.) CONCLUSION Surgical complications following SPK transplantation can cause significant morbidity and adversely affect pancreas graft survival, but do not affect long-term kidney or patient survival.


Pediatric Nephrology | 2009

A fatal case of cerebral oedema with hyponatraemia and massive polyuria after renal transplantation

Janette Cansick; Lesley Rees; Geoff Koffman; William van’t Hoff; Detlef Bockenhauer

We report the case of a child who died from severe cerebral oedema in the context of hyponatraemia and extreme polyuria immediately after renal transplantation. The patient was treated according to a standard post-transplantation protocol, receiving 0.45% saline solution for urine output replacement. The case highlights the dangers of massive fluid therapy in the context of polyuria and, therefore, the need for intensive monitoring.


Transplantation | 2013

Clinically Significant Peripancreatic Fluid Collections After Simultaneous Pancreas-Kidney Transplantation

R. P. Singh; Georgios Vrakas; Samiha Hayek; Sara Hayek; Sadia Anam; Mariam Aqueel; Jonathon Olsburgh; Francis Calder; Nizam Mamode; C. J. Callaghan; Nicos Kessaris; James M. Pattison; Rachel Hilton; Geoff Koffman; J. Taylor; Martin Drage

Background Peripancreatic fluid collections (PPFC) are a serious complication after simultaneous pancreas-kidney transplantation (SPKTx). Methods Retrospective study for all 223 SPKTx performed from December 8, 1996, to October 10, 2011, to evaluate the risk factors (RF) and impact of PPFCs on outcomes was conducted. Results Clinically significant PPFCs were seen in 36 (16%) cases, all within 3 months after transplantation. Radiologic drainage resolved 2 (6%) cases, and 34 required laparotomy (mean [SD], 4 [7]). Compared with the non-PPFC group (n=186), the PPFC group had similar patient and total kidney graft survivals but significantly lower total pancreas survival (68% vs. 85%) and greater incidence of infections (75% vs. 46%, all P<0.05) at 5 years. PPFCs were associated with early graft pancreatitis in 18 (50%), pancreatic fistula in 20 (56%, 9 with obvious duodenal stump leak) and infection in the collection in 20 (56%) cases. Comparison of PPFCs with pancreas graft loss to the PPFCs with surviving grafts showed that the incidence of pancreatic fistula was greater in the former (90% pancreas graft loss vs. 42% pancreas graft survival, P<0.01). Binary logistic regression analysis of RF for developing PPFC showed a donor age >30 years to be significant (P=0.03; odds ratio, 3.4; confidence interval, 1.1–10.5) and a trend of association with donor body mass index >30 and pancreas cold ischemia time greater than 12 hr. Conclusions PPFCs are associated with significant reduction in pancreas allograft survival and impact resource use. Donor age >30 years is a significant RF for their development. PPFCs associated with pancreatic fistula carry a greater risk for pancreas graft loss.


Annals of The Royal College of Surgeons of England | 2011

Native nephrectomy in transplant patients with autosomal dominant polycystic kidney disease

Parul Patel; Catherine Horsfield; Frederick J. Compton; Judith Taylor; Geoff Koffman; Jonathon Olsburgh

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Nizam Mamode

Guy's and St Thomas' NHS Foundation Trust

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J. Taylor

Guy's and St Thomas' NHS Foundation Trust

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J. Olsburgh

Guy's and St Thomas' NHS Foundation Trust

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R. P. Singh

Guy's and St Thomas' NHS Foundation Trust

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Rachel Hilton

Guy's and St Thomas' NHS Foundation Trust

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Nicos Kessaris

Guy's and St Thomas' NHS Foundation Trust

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