Browsing by Author "Rayner, Brian L"

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    An audit of acute kidney injury : a prospective study of the epidemiology, management and outcome of patients with acute kidney injury, over a 12 month period at Groote Schuur Hospital, Cape Town, South Africa
    (2014) Dlamini, Thandiwe Angela Lerato; Rayner, Brian L
    Introduction: Acute kidney injury results from a rapid decline in kidney function. There are many potential causes, some of which are preventable. It carries the risks of mortality, progression to chronic kidney disease and worsening of pre-existing chronic kidney disease. There is a scarcity of data on the epidemiology of acute kidney injury in sub-Saharan Africa. The aims of this study were to describe the epidemiology of acute kidney injury at Groote Schuur hospital, and factors associated with mortality and renal recovery. Methods: This was a prospective observational study of patients with acute kidney injury, referred to Groote Schuur Hospital Renal Unit from the 8th of July 2012 to the 8th of July 2013. Ethics approval was granted by the University of Cape Town Human Research Ethics Committee. We excluded patients younger than 13 years, kidney transplant patients, and those not fulfilling the consensus definition of acute kidney injury according to the Kidney Disease: Improving Global Outcomes (KDIGO) group. Data on patient demographics, medical history, clinical observations, investigations, and cause of acute kidney injury was collected from a clerking sheet designed for the study. Patients were followed up at, or after 3 months (90 days) for assessment of survival and renal recovery. The main outcomes were recovery of renal function and mortality at 3 months. Data was entered into an Excel spreadsheet, and imported onto Stata 12.1 for analysis. Results: A total of 366 patients were included. The median age was 44 years (IQR 14-82). Of these 214 were male (58.5%). Referrals were from medical, surgical and obstetrics and gynaecology departments. The majority, 217 (59.3%) were medical referrals. Most, 265 (72.4%) had community acquired acute kidney injury. The majority of the 101 patients with hospital acquired acute kidney injury, 72 (71.3%) had severe, stage 3 acute kidney injury. Hypertension was the commonest co-morbidity, present in 152 (41.5%) of the patients. There were 75 (20.6%) HIV positive patients. Acute tubular necrosis was the most common cause of acute kidney injury, identified in 251 (68.6%) patients. Renal biopsies were carried out in 36 (9.8%) patients. More than half, 202 (55.2%), of the patients were in the intensive care unit, while 204 (55.7%) were dialysed. Fluid input was recorded in 140 patients (38.3%). Overall 3 month mortality was 38.8% (142 patients). Of the 224 surviving patients, 119 (53.1%) had a follow up serum creatinine. Of these, 95 (80.5%) had full renal recovery, and 4 (3.4%) went on to end stage renal disease. On multivariate analysis, mechanical ventilation was strongly associated with mortality at 3 months (OR 2.46, p-value 0.0 19, 95% CI 1.41-4.03). Sepsis had a borderline significant association with 3 month mortality (OR 1.83, P-value 0.066, 95%CI 1.02 – 3.27), as did prolonged time to dialysis (OR 1.93, p-value 0.080, 95% CI 0.93 – 4.03). HIV was not associated with mortality on univariate analysis (OR 1.07, p-value 0.801, 95%CI 0.64-1.80). Conclusions: Acute kidney injury carries a high mortality risk, most significant in mechanically ventilated patients. Sepsis and, in those dialysed, late dialysis, may be associated with a high risk of mortality. Efforts to reduce hospital acquired acute kidney injury and to improve patient fluid balance chart records should be made.
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    Characteristics and allocation outcomes of patients assessed for the renal replacement therapy at Groote Schuur Hospital (2008-2012)
    (2014) Kilonzo, Kajiru; Rayner, Brian L
    End Stage Kidney Disease (ESKD) is a global public health problem with an enormous economic burden. In resource limited settings like South Africa management of End Stage Kidney Diseases is rationed to the most transplantable candidates. Racial and socio-economic inequalities in selecting candidates have been documented in a South Africa despite the availability of guidelines. No data is available on selection outcomes using the current 2010 prioritization guidelines of Western Cape. We audited the outcome of patients assessed for the renal replacement therapy at Groote Schuur hospital. A retrospective analytic study of patients presented to the renal replacement therapy committee was conducted in the renal unit of Groote Schuur Hospital. Outcome letters, proceedings from the committee meetings and the hospital database were sources of data used. All new patients presented between 2008 and 2012 were included in the study. Data entry and statistical analysis was done using SPSS v.22. A total of 734 ESKD patients were assessed for renal replacement therapy between January, 2008 and December, 2012. During that period, there were 564 new patients, of which more than half (53.9%) were not selected for the program. Following the introduction of the new prioritization criteria a trend towards increasing number of patients presented and accepted was noted. More males were presented (M: F = 1.3) and most patients were below the age of 50yrs (n=478, 84.8%). Half of the patients came from low socioeconomic areas. There were no significant differences in socio-demographic factors before and after introduction of the new guidelines. Clinically they had advanced disease with either uremic (n=181, 44.4%) or fluid overload (n=179, 43.9%) symptoms as their major presentation. The underlying causes were Hypertension (40.6%), Diabetes (14.4%) and chronic Glomerulonephritis (15.8%). Predictors of rejection from the program included age above 50 years, unemployment and a poor psychosocial assessment. Substance abuse and Diabetes also showed a statistical significant association with the likelihood of being rejected. Race and marital status were not predictors. Efforts to allocate more resources should continue in view of the loss of young and potential productive life. Advanced presentation of patients with ESRD represents challenges in early diagnosis and referral in the current system. Community screening programs and improved access to knowledgeable clinicians at the primary level is advocated. The use of new selection guidelines have not led to an increase in selection inequalities.
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    Community acquired bacteraemia : a prospective survey of 239 cases
    (1989) Rayner, Brian L; Willcox, Paul A
    The incidence and epidemiology of bacteraemia has been widely reported in the United States and Europe but little data is available from Southern Africa. In addition, most studies have concentrated on the overall incidence of bacteraemia, on individual organisms, or clinical situations, and it is difficult to interpret the data from these studies with regard to community acquired bacteraemia. From a retrospective survey of summaries from a single medical ward at Groote Schuur Hospital it was estimated that bacteraemia accounted for about 4% of the total admissions. It was therefore thought useful to provide clinicians particularly at Groote Schuur Hospital with information about community acquired bacteraemia to improve overall patient management. With this in mind it was decided to undertake a comprehensive prospective study of community acquired bacteraemia at Groote Schuur Hospital.
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    Genetic variation at selected SNPs in the leptin gene and association of alleles with markers of kidney disease in a Xhosa population of South Africa
    (Public Library of Science, 2010) Okpechi, Ikechi G; Rayner, Brian L; van der Merwe, Lize; Mayosi, Bongani M; Adeyemo, Adebowale; Tiffin, Nicki; Ramesar, Rajkumar
    BACKGROUND: Chronic kidney disease (CKD) is a significant public health problem that leads to end-stage renal disease (ESRD) with as many as 2 million people predicted to need therapy worldwide by 2010. Obesity is a risk factor for CKD and leptin, the obesity hormone, correlates with body fat mass and markers of renal function. A number of clinical and experimental studies have suggested a link between serum leptin and kidney disease. We hypothesised that variants in the leptin gene ( LEP ) may be associated with markers of CKD in indigenous black Africans. METHODOLOGY/PRINCIPAL FINDINGS: Black South Africans of Xhosa (distinct cultural Bantu-speaking population) descent were recruited for the study and four common polymorphisms of the LEP (rs7799039, rs791620, rs2167270 and STS-U43653 [ENSSNP5824596]) were analysed for genotype and haplotype association with urine albumin-to-creatinine ratio (UACR), estimated glomerular filtration rate (eGFR), Serum creatinine (Scr) and serum leptin level. In one of the four single nucleotide polymorphisms (SNPs) we examined, an association with the renal phenotypes was observed. Hypertensive subjects with the T allele (CT genotype) of the ENSSNP5824596 SNP had a significantly higher eGFR (p = 0.0141), and significantly lower Scr (p = 0.0137). This was confirmed by haplotype analysis. Also, the haplotype GAAC had a modest effect on urine albumin-to-creatinine ratio in normotensive subjects (p = 0.0482). Conclusions/Significance These results suggest that genetic variations of the LEP may be associated with phenotypes that are markers of CKD in black Africans.
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    The impact of vascular calcification on ambulatory and central aortic blood pressure in a South African dwelling dialysis population : a clinical, radiological and pathophysiological study of vascular health in a young prevalent dialysis population in a developing country
    (2011) Freercks, Robert Jeremy; Rayner, Brian L; Swanepoel, Charles
    In Sub-Saharan Africa, the prevalence of vascular calcification (VC) in CKD-5D is unknown. We undertook to determine the effect of ethnicity on VC, the risk factors for VC, the utility of abdominal X-ray (AXR) in predicting coronary calcium score (CCS) and the effect of VC on central aortic systolic pressure (CASP) and left ventricular mass index (LVMI) in South African dialysis patients. ... Black race significantly protects from VC in South African CKD-5D patients and warrants further study. The AXR is a useful screening tool for CCS in our population. VC does not appear to influence CASP in our population.
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    Investigation of the ethnic differences and genetics of salt sensivity and salt-sensitive hypertension in South Africa
    (2013) Rayner, Brian L
    Includes abstract. Includes bibliographical references.
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    Outcome of patients with primary immune-complex type Mesangiocapillary Glomerulonephritis (MCGN) in Cape Town South Africa
    (Public Library of Science, 2014) Okpechi, Ikechi G; Dlamini, Thandiwe A L; Duffield, Maureen; Rayner, Brian L; Moturi, George; Swanepoel, Charles R
    Background and Aim Mesangiocapillary glomerulonephritis (MCGN) is a common cause of chronic kidney disease in developing countries. Data on the renal outcome of patients with idiopathic MCGN is limited. The aim of this study is to investigate the outcome of patients with idiopathic MCGN presenting to the Groote Schuur Hospital (GSH) Renal Unit in Cape Town. Materials and METHODS: A retrospective study of patients with idiopathic MCGN followed up at our clinic. Seventy-nine patients with no identifiable cause of MCGN were included for analysis. A composite renal outcome of persistent doubling of serum creatinine or end stage renal disease (ESRD) was used. Kaplan Meier survival and Cox regression analysis were used to assess survival and identify factors predicting the outcome. RESULTS: The mean age at biopsy was 33.9±13.6 years and 41.8% were black. Mean duration of follow up was 13.5±18.8 months. Twenty-three patients (34.2%) reached the composite endpoint. Overall, median renal survival was 38.7±11.7 months (95% CI 15.7-61.8) with 2-year and 5-year renal survival of 61% and 40.3% respectively. No significant difference was found for renal survival between males and females, treatment or non-treatment with immunosuppression, presence or absence of crescents or histological type of MCGN (p>0.05). On univariate Cox-regression analysis, factors found to be associated with the outcome were the estimated glomerular filtration rate at biopsy (OR 0.97 [95%CI: 0.95-0.99], p<0.0001), black race (OR 3.03 [95%CI: 1.27-7.21], p = 0.012) and presence of interstitial fibrosis in the biopsy (OR 2.64 [95%CI: 1.07-6.48], p = 0.034). Age, systolic blood pressure and attaining complete or partial remission approached significant values with the endpoint. CONCLUSIONS: The outcome of idiopathic MCGN in Cape Town is poor and requires further prospective studies to improve our understanding of this common disease.
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    Study of epidemiology, management and outcome of acute kidney injury post noncardiac surgery over 12 months at Groote Schuur Hospital, Cape Town
    (2015) Mzingeli, Luvuyo; Rayner, Brian L
    INTRODUCTION : Acute kidney injury (AKI) is a disorder that is defined by rising serum creatinine and reduced urine output. It occurs in approximately 1-7% of hospitalized patients and is a major predictor of morbidity and mortality. It increases the costs and duration of hospital stay. AKI has been extensively studied post cardiac surgery, but there has been little attention on AKI occurring after non cardiac surgery . There have been few studies on AKI from developing countries and a paucity of data of post non cardiac surgery AKI. OBJECTIVE : To identify which known risk factors for AKI are commonly encountered at Groote Schuur Hospital, to document 30 and 90 day mortality, length of hospital stay, recovery of renal function at 90 days and identify factors associated with outcome post non-cardiac surgery. DESIGN: Prospective observational study. SETTING: Surgical Wards and ICU. PARTICIPANTS: Patients with AKI post non-cardiac surgery admitted between July 2012 and July 2013, who were 18 years and above without underlying stage 5 chronic kidney disease. OUTCOME MEASURES: Mortality, identification of risk factors, length of hospital stay and recovery of renal function. RESULTS: Of 367 patients referred to renal unit with AKI, 60 patients met inclusion criteria. Patients had an average age of 52.8 years (standard deviation 16.6) and 70% (42/60) were male. 61.7% (37 /60) were Coloured, 20% (12/60) were White and 18.3% (11/60) were Black. These patients were exposed to the following risk factors: 80%(48/60) had emergency surgery, 66. 7%(40/60) had sepsis, 65%(39/60) had perioperative contrast exposure, 53.3%(32/60) had hypotension that required inotropic support in 50%(30/60). Mortality was 33.3% (20/60) at 30 days and 45% (27/60) at 90 days. Of the 33 patients who did not die, 81.8% (27 /33) recovered their renal function to normal baseline creatinine at 90 days. Of the 6 patients, whose renal function did not return to baseline, none required long term dialysis. Perioperative contrast exposure was associated with a longer median length of hospital stay compared to patients not exposed to contrast (21 vs 16 days respectively, p<0.05). Sepsis and age > 60 years was associated with poor recovery of renal function (p=0.005, p=0.01 respectively). No risk factor was identified to be associated with mortality. CONCLUSION: Risk factors for post non cardiac surgery AKI commonly encountered at Groote Schuur Hospital were emergency surgery, sepsis, hypotension, perioperative use of inotropes and perioperative contrast exposure. The latter was identified as a modifiable risk factor which significantly prolonged hospital stay. Sepsis and age > 60 years were associated with poorer recovery of renal function.
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    The effects of add-on corticosteroids on renal outcomes in patients with biopsy proven HIV associated nephropathy: a single centre study from South Africa
    (BioMed Central, 2019-02-06) Wearne, Nicola; Swanepoel, Charles R; Duffield, Maureen S; Davidson, Bianca J; Manning, Kathryn; Tiffin, Nicki; Boulle, Andrew; Rayner, Brian L; Naidu, Priyanka; Okpechi, Ikechi G
    Background The aim of this study was to assess, the efficacy and safety of add-on corticosteroids to antiretroviral therapy [ART] in patients with biopsy proven HIV associated nephropathy. Methods All included patients had histological evidence of either collapsing or non-collapsing focal segmental glomerulosclerosis (FSGS) or podocyte and/or parietal cell hypertrophy or hyperplasia. All patients had evidence of tubulointerstitial inflammation with microcysts. Patients were randomized to ART with the addition of 1 mg/kg of corticosteroids [ART+C] or remained in the group [ART Alone] and followed for 2 years. A repeat biopsy was performed at 6 months. Results Twenty-one patients were randomized to [ART+C] and 17 to [ART Alone]. The baseline estimated glomerular filtration rate (eGFR) was significantly lower in the [ART+C] vs. [ART Alone] group [35mls/min/1.73m2 vs. 47 mls/min/1.73m2, p = 0.015]. The [ART+C] cohort had a statistically significant improvement in median (eGFR) from baseline to last follow up compared with [ART Alone] i.e. [Δ = 25mls/min (IQR: 15;51) vs 9 mls/min (IQR: 0–24), p = 0.008]. There were no statistically significant differences between the groups when proteinuria and histology were analyzed. There were 8 deaths during the trial period, 7 from [ART+C] (Log rank p = 0.071). Conclusions In the [ART+C] cohort there was a significant improvement in eGFR over 2-years with increased mortality. Routine corticosteroid use cannot currently be recommended. Further investigation to define which subgroup of this cohort would safely benefit from the positive effects is required. Trial registration ISRCTN study ID ( 56112439 ] was retrospectively registered on the 5 September 2018.