Routine Monitoring Of Renal Function Research Articles

Frequency of Acute Kidney Injury in Patients Presenting with Acute ST-Elevation Myocardial Infarction and Its Relationship with In-Hospital Mortality

Objective: To determine the frequency of acute kidney injury in patients presenting with acute ST elevation myocardial infarction and to compare the frequency of in-hospital mortality between patients presenting with acute ST elevation myocardial infarction with versus without acute kidney injury at a tertiary care hospital. Design: It was a descriptive case series. Study Settings: Department of Cardiology, Shaikh Zayed Hospital Lahore-Pakistan over a period of 6 months from January 2021 to June 2021. Material and Methods: A total of 128 patients of both genders aged between 18-70 years presenting with in first 12 hours of acute STEMI at emergency ward of cardiology department were included in this descriptive case series study. An informed written consent was taken from all the participants. All these patients were managed as per standard departmental protocols. Renal function was assessed within 30 minutes of presentation and then after 72 hours of admission and acute kidney injury was labelled if there was ≥0.5 mg/dl increase in serum creatinine level from baseline. These patients were followed till discharge and death of the patient during hospital stay was noted. It was then compared between patients with versus without acute kidney injury. Results: The patients had mean age of 53.8±11.3 years. There were 86 (67.2%) males and 42 (32.8%) females with a male to female ratio of 2.1:1. 97 (75.8%) patients were obese, 65 (50.8%) patients were diabetic and 87 (68.0%) patients were hypertensive. 72 (56.3%) patients were active smokers. 25 (19.5%) patients with acute STEMI developed acute kidney injury while 10 (7.8%) patients died during hospital stay. The frequency of in-hospital mortality was significantly higher in acute STEMI patients with AKI as compared to those without AKI (24.0% vs. 3.9%; p-value=0.004). When compared similar difference was noted in in-hospital mortality between acute STEMI patients with versus without AKI across various subgroups based on age, gender, BMI, diabetes, hypertension, smoking, ASA status, thrombolysis and need for PCI. Conclusion: A substantial proportion of patients presenting with acute ST-segment elevation myocardial infarction developed acute kidney injury that was associated with increased frequency of mortality among such patients which warrants routine monitoring of renal function among patients presenting with acute ST-segment elevation myocardial infarction and consideration of cases positive of AKI at higher risk of mortality so that risk stratification and anticipated management may improve the outcome of such patients in future practice. Keywords: Acute ST Elevation Myocardial Infarction, Acute Kidney Injury, In-Hospital Mortality.

Long-Term Survival and Kidney Function in Pediatric Patients Following Liver Transplantation: A 15-Year Retrospective Cohort Study.

Long-term preservation of kidney function after liver transplantation (LT) has not been well studied. We thus evaluated the rates of kidney function preservation and long-term survival after pediatric LT. We also investigated the risk factors associated with the progression of chronic kidney disease (CKD). We conducted a retrospective study of 184 pediatric patients who had undergone LT from 2003 to 2018 at a university hospital. We collected demographics, primary indications for LT, liver disease scores, renal function test results, immunosuppressive drug prescriptions, and diagnosis of post-LT complications. The 15-year survival rate was 90.8%. Furthermore, the rate of kidney function preservation at 14 years post-LT in patients at high risk of renal disease was 79.3%, and that in those with less risk of kidney diseases was 96.0%. Arterial hypertension was an independent risk factor associated with CKD progression. However, when arterial hypertension was excluded, the use of cyclosporine and liver disease with renal involvement were risk factors for CKD progression. We found that kidney function after pediatric LT was well preserved. We encourage the early detection of underlying kidney involvement, routine monitoring of renal function for high-risk patients, active control of hypertension, and appropriate immunosuppressive regimens for pediatric patients with LT.

Smartphone-based automated estimation of plasma creatinine from finger-pricked blood on a paper strip via single-user step sample-to-result integration

Measuring creatininelevels in blood plasma is one of the most commonly used means of routine monitoring of renal function. Point-of-care devicesfor creatinine level estimation potentially allow rapid measurement, facilitating continuous monitoring of vulnerable patients. However, a majority of such devices currently available is constrained by several factors such as lack of simplicity in fabrication and operation (including plasma separation), a limited regime of efficacy, compromised reagent stability, and elevated costs. Here, we report the invention of a simple-to-fabricate and easy-to-use paper strip for rapid evaluation of plasma creatinine levels (ranging from 0.1 to 15 mg dL-1) in an integrated single-step process. For the testing, one drop of whole blood is first dripped onto the calcium salt-functionalized sample pad of the strip. Subsequently, blood plasma separation occurs due to spontaneous aggregation of red blood cells (RBCs) in the presence of calcium ions. The plasma spontaneously traverses into the reaction zone of the test-strip via capillary action where it reacts with previously dispensed alkaline picrate reagent, resulting in a colorimetric signal. Smartphone-interfaced imaging and image analytics of the reaction spot renders the dissemination of the test result in a turn-around time of about 2–3 min, without necessitating additional device interfacing. High efficacy of performance is established by validating with the results obtained from laboratory-benchmarked biochemical auto-analyzer, exhibiting an accuracy of 94%, and the coefficient of variation ranging from 0.64 to 6.4%. Suitability of use in extreme resource-limited settings is established by favorable stability of the reagents outside controlled laboratory ambience and engagement of unskilled personnel to execute the testing procedure with uncompromised accuracy.

Effects of metabolic syndrome on renal function after radical nephrectomy in patients with renal cell carcinoma

Nephrectomy, partial or radical, remains the standard treatment for renal cell carcinoma (RCC). However, increased risk of chronic kidney disease (CKD) must still be considered. This study aimed to evaluate the effects of concomitant metabolic syndrome (MetS) on renal function in patients with RCC after radical nephrectomy. Medical records of 310 patients who underwent radical nephrectomy for clear-cell RCC at 900th Hospital of the Joint Logistics Support Force, PLA from December 2012 to January 2017 were reviewed retrospectively. Estimated glomerular filtration rate (eGFR) and CKD stages were calculated at one week preoperative as baseline and then at postoperative 1week, 3months, 12months and 24months. MetS patients were identified and enrolled in the MetS group (n = 31), and a non-MetS group was selected by propensity score matching (n = 31). Non-neoplastic renal parenchyma specimens taken at least 2cm from edge of tumor were evaluated. Baseline characteristics between the two groups were comparable. At 24months postoperative, mean eGFR levels of the MetS group were significantly lower than those in the non-MetS group (62.7 vs. 73.3ml/min/1.73 m2; p = 0.004). CKD stages were still more severe in the MetS group than those in the non-MetS group (p = 0.006). The proportions of global sclerosis, tubular atrophy and interstitial fibrosis were all significantly more prevalent in MetS patients, compared to non-MetS patients (all p < 0.05). In RCC patients with MetS, the possibility of declining eGFR and CKD progression must be considered after radical nephrectomy. Routine monitoring of renal function must be emphasized.

SGLT2 inhibitors: practical considerations and recommendations for cardiologists.

To address common concerns regarding sodium-glucose cotransporter 2 (SGLT2) inhibitor use for patients with type 2 diabetes mellitus (T2DM) in cardiovascular practice. SGLT2 inhibitors provide glycemic control and improve cardiovascular and renal endpoints in T2DM. Cardiovascular outcome trials have demonstrated sustained cardiovascular, heart failure and renal benefits independent of glycemic control, which persist down to an eGFR of 30 ml/min/1.73 m. SGLT2 inhibitors can be safely administered alongside common diuretics, and routine monitoring of renal function is advised at initiation of therapy, particularly for patients on loop diuretics. Mild initial reductions in eGFR are expected, usually stabilizing over time. The most common adverse effect noted with SGLT2 inhibitors is genital mycotic infections, primarily in women. Less common, but concerning effects associated with canagliflozin include increased risk of fractures and lower limb amputations, particularly in patients with previous amputation history. Overall, SGLT2 inhibitors are well tolerated and effective adjuncts to diabetic treatment, for which the benefits seem to outweigh the risks. The care of patients with T2DM requires an interdisciplinary team approach, within which the role of cardiologists is expanding. SGLT2 inhibitors are an encouraging treatment option for achieving glycemic control, whilst also improving cardiovascular and renal outcomes.

Renal Manifestations of Inflammatory Bowel Disease.

Renal and urinary involvement has been reported to occur in 4% to 23% of inflammatory bowel disease (IBD) patients. Parenchymal renal disease is rare and most commonly affects glomerular and tubulointerstitial compartments. The most common findings on renal biopsy of IBD patients are IgA nephropathy and tubulointerstitial nephritis. Overall morbidity of IBD-related renal manifestations is significant, and there is often only a short window of injury reversibility. This, along with subtle clinical presentation, requires a high index of suspicion and routine monitoring of renal function. There are no established guidelines for the optimal screening and monitoring of renal function in IBD patients.

COHORT PROFILE: The Complications of Long-Term Antiretroviral Therapy study in Uganda (CoLTART), a prospective clinical cohort

BackgroundAntiretroviral therapy (ART) improves the survival and quality of life of HIV-positive individuals, but the effects of long-term ART use do eventually manifest. The Complications of Long-Term Antiretroviral Therapy cohort study in Uganda (CoLTART) was established to investigate the metabolic and renal complications of long-term ART use among Ugandan adults. We describe the CoLTART study set-up, aims, objectives, study methods, and also report some preliminary cross–sectional study enrolment metabolic and renal complications data analysis results.MethodsHIV-positive ART naïve and experienced adults (18 years and above) in Uganda were enrolled. Data on demographic, dietary, medical, social economic and behaviour was obtained; and biophysical measurements and a clinical examination were undertaken. We measured: fasting glucose and lipid profiles, renal and liver function tests, full blood counts, immunology, virology and HIV drug resistance testing. Plasma samples were stored for future studies.ResultsBetween July 2013 and October 2014, we enrolled 1095 individuals, of whom 964 (88.0%) were ART experienced (6 months or more), with a median of 9.4 years (IQR 7.0–9.9) on ART. Overall, 968 (88.4%) were aged 35 years and above, 711 (64.9%) were females, 608 (59.6%) were or had ever been on a Tenofovir ART regimen and 236 (23.1%) on a Protease Inhibitor (PI) regimen. There were no differences in renal dysfunction between patients on Tenofovir and Non-Tenofovir containing ART regimens. Patients on PI regimens had higher total cholesterol, lower high density lipoprotein, higher low density lipoprotein, higher triglycerides, and a high atherogenic index for plasma than the non-PI regimen, p = 0.001 or < 0.001. Patients on Non-PI regimens had higher mean diastolic hypertension than patients on PI regimens, p < 0.001.ConclusionsOur finding of no differences in renal dysfunction between patients on Tenofovir and those on Non-Tenofovir containing ART regimens means that Tenofovir based first line ART can safely be initiated even in settings without routine renal function monitoring. However, integration of cardiovascular risk assessment, preventive and curative measures against cardiovascular disease are required. The CoLTART cohort is a good platform to investigate the complications of long-term ART use in Uganda.

The effect of Tenofovir on renal function among Ugandan adults on long-term antiretroviral therapy: a cross-sectional enrolment analysis.

BackgroundWHO recommends using Tenofovir containing first line antiretroviral therapy (ART), however, Tenofovir has been reported to be associated with renal impairment and dysfunction. We compared renal function among individuals on Tenofovir and those on non-Tenofovir containing ART.MethodsIn a cross-sectional study of HIV-Positive adults on ART, at enrolment into a prospective cohort to study the long-term complications of ART in Uganda, information on biophysical measurements, medical history, clinical examination and renal function tests (RFTs) was collected. Fractional Tubular phosphate reabsorption and estimated glomerular filtration rate (eGFR) were calculated. Mean values of RFTs and proportions with abnormal RFTs were compared between non-Tenofovir containing (Non-TDF) and Tenofovir containing (TDF-ART) ART regimen groups using a general linear regression model. Durations of TDF exposure were also compared.ResultsBetween July 2013 and October 2014, we enrolled 953 individuals on ART for 6 or more months, median duration on ART was 9.3 years, 385 (40.4 %) were on non-TDF and 568 (59.6 %) on TDF-ART regimens. The proportion of participants with Proteinuria (>30 mg/dl) was higher among the TDF-ART group than the non-TDF ART group. However, in multivariable analysis, there were no significant differences in the adjusted mean differences of eGFR, serum urea, serum creatinine, fractional tubular reabsorption of phosphate and serum phosphates when patients on TDF-ART were compared with those on non-TDF containing ART. There were no differences in renal function even when different durations on Tenofovir were compared.ConclusionsWe found no differences in renal function among patients on Tenofovir and non-Tenofovir containing ART for almost a decade. Tenofovir based first line ART can therefore safely be initiated even in settings without routine renal function monitoring.

Renal Dysfunction during Tenofovir Use in a Regional Cohort of HIV-Infected Individuals in the Asia-Pacific.

BackgroundIn resource-limited settings, routine monitoring of renal function during antiretroviral therapy (ART) has not been recommended. However, concerns for tenofovir disoproxil fumarate (TDF)-related nephrotoxicity persist with increased use.MethodsWe investigated serum creatinine (S-Cr) monitoring rates before and during ART and the incidence and prevalence of renal dysfunction after starting TDF by using data from a regional cohort of HIV-infected individuals in the Asia-Pacific. Time to renal dysfunction was defined as time from TDF initiation to the decline in estimated glomerular filtration rate (eGFR) to <60 ml/min/1.73m2 with >30% reduction from baseline using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation or the decision to stop TDF for reported TDF-nephrotoxicity. Predictors of S-Cr monitoring rates were assessed by Poisson regression and risk factors for developing renal dysfunction were assessed by Cox regression.ResultsAmong 2,425 patients who received TDF, S-Cr monitoring rates increased from 1.01 to 1.84 per person per year after starting TDF (incidence rate ratio 1.68, 95%CI 1.62–1.74, p <0.001). Renal dysfunction on TDF occurred in 103 patients over 5,368 person-years of TDF use (4.2%; incidence 1.75 per 100 person-years). Risk factors for developing renal dysfunction included older age (>50 vs. ≤30, hazard ratio [HR] 5.39, 95%CI 2.52–11.50, p <0.001; and using PI-based regimen (HR 1.93, 95%CI 1.22–3.07, p = 0.005). Having an eGFR prior to TDF (pre-TDF eGFR) of ≥60 ml/min/1.73m2 showed a protective effect (HR 0.38, 95%CI, 0.17–0.85, p = 0.018).ConclusionsRenal dysfunction on commencing TDF use was not common, however, older age, lower baseline eGFR and PI-based ART were associated with higher risk of renal dysfunction during TDF use in adult HIV-infected individuals in the Asia-Pacific region.

Direct oral anticoagulant use and the incidence of bleeding in the very elderly with atrial fibrillation.

Atrial fibrillation (AF) is a major risk factor for stroke in the elderly population. The use of anticoagulation in patients with AF greatly reduces the risk for stroke, but results in an increased risk of bleeding. Over the past several years, direct oral anticoagulants (DOACs, dabigatran, rivaroxaban, and apixaban) have been used in place of warfarin for stroke prevention in AF. We conducted a retrospective cohort study to assess the safety of DOACs in very elderly patients (75+) managed in a health care system encompassing both community and academic settings. We found that 36% of patients had moderate to severe renal failure (estimated glomerular filtration rate<59ml/min/1.73m(2)) at the time of DOAC initiation. 142 patients were followed for a mean of 2.56years, and five experienced a major bleeding episode while on anticoagulation, for a rate of 1.37 per 100 person years. All major bleeding episodes were associated with a decline in GFR compared to baseline. There were 12 non-major bleeding episodes reported. HAS-BLED scores were similar for those patients who experienced bleeding complications compared to those who did not. 21% of patients were prescribed an inappropriately low dose of DOAC based on approved recommendations. DOACs appear to be a safe form of anticoagulation in very elderly patients with AF. However, the decline in GFR among patients with major bleeding highlights the importance of routine renal function monitoring.

Identifying evidence of cardio-renal syndrome in patients with Duchenne muscular dystrophy using cystatin C

Patients with Duchenne muscular dystrophy (DMD) develop dilated cardiomyopathy and are at risk for kidney injury. Creatinine based estimated glomerular filtration rate (eGFR) is limited by low muscle mass with low serum creatinine levels in DMD. We assessed the relationship between cardiac function, modified Schwartz eGFR and cystatin C eGFR in patients with DMD. Ninety-three patients with DMD were screened for renal dysfunction in an outpatient neuromuscular clinic. Patients with new nephrotoxic medications, recent hospitalization or decompensated heart failure were excluded from the analysis. Eleven (12%) patients had evidence of renal dysfunction identified by cystatin C eGFR, while no patients had renal dysfunction by Schwartz eGFR. There was no significant correlation between cystatin C eGFR and age (r = −0.2, p = 0.11), prednisone dose (r = 0.06, p = 0.89) or deflazacort dose (r = −0.01, p = 0.63). There was a significant correlation between left ventricular ejection fraction and cystatin C GFR among patients with chronic left ventricular dysfunction (r = 0.46, p < 0.01), but not normal function (r = −0.07, p = 0.77). There was no significant correlation between left ventricular ejection fraction and Schwartz eGFR among patients with (r = 0.07, p = 0.59) or without (r = −0.27, p = 0.07) chronic left ventricular dysfunction. Cystatin C eGFR correlates with cardiac dysfunction in patients with DMD, thus providing novel evidence of cardio-renal syndrome in this population. Routine monitoring of renal function is recommended in patients with DMD.

Autoimmune polyglandular syndrome type I can have significant kidney disease in children including recurrence in renal allograft – a report of two cases

Autoimmune polyglandular syndrome type 1 (APS 1) is an autosomal recessive disorder characterized by immune injury of multiple organ systems (primarily endocrine) secondary to a mutation in the autoimmune regulator (AIRE) gene. In some cases, patients develop tubulointerstitial nephritis (TIN) and progress to end-stage renal failure (ESRD). We describe two patients with APS 1 and TIN. In both cases, TIN was clinically silent and the diagnosis was confirmed by renal biopsy. In one patient, renal function remained stable with immunosuppressive therapy. A second patient progressed to ESRD despite treatment, and received a deceased donor allograft. TIN recurred in the transplanted kidney and was reversed successfully with rituximab. Severe, recurrent esophageal candidiasis also resolved. TIN is an important complication of APS 1 that may result in ESRD, and may recur in the transplanted kidney. TIN may be under-recognized, as the presentation is unapparent clinically and urinalysis remains normal. Immunosuppressive therapy may be effective and, therefore, routine monitoring of renal function is warranted in asymptomatic individuals.

Is There Evidence of Any Safety Differences Among DPP-4 Inhibitors in the Treatment of People with Type 2 Diabetes Mellitus and Reduced GFR Due to Chronic Kidney Disease?

Is There Evidence of Any Safety Differences Among DPP-4 Inhibitors in the Treatment of People with Type 2 Diabetes Mellitus and Reduced GFR Due to Chronic Kidney Disease?

Effect of Baseline Renal Function on Tenofovir-Containing Antiretroviral Therapy Outcomes in Zambia

Although tenofovir disoproxil fumarate (TDF) use has increased as part of first-line antiretroviral therapy (ART) across sub-Saharan Africa, renal outcomes among patients receiving TDF remain poorly understood. We assessed changes in renal function and mortality in patients starting TDF- or non-TDF-containing ART in Lusaka, Zambia.We included patients aged ≥16 years who started ART from 2007 onward, with documented baseline weight and serum creatinine. Renal dysfunction was categorized as mild (estimated glomerular filtration rate [eGFR], 60-89 mL/min), moderate (30-59 mL/min), or severe (<30 mL/min) according to the chronic kidney disease-epidemiology (CKD-EPI) formula. Differences in eGFR during ART were analyzed using linear mixed-effect models. The odds of developing moderate or severe eGFR decrease and mortality were assessed using logistic and competing risk regression, respectively.We included 62 230 adults, of which 38 716 (62.2%) initiated a TDF-based regimen. The proportion with moderate or severe renal dysfunction at baseline was lower in the TDF than in the non-TDF group (1.9% vs 4.0%). Among patients with no or mild renal dysfunction, those receiving TDF were more likely to develop moderate (adjusted odds ratio, 3.11; 95% confidence interval, 2.52-3.87) or severe (2.43; 1.80-3.28) eGFR decrease, although the incidence in such episodes was low. Among patients with moderate or severe renal dysfunction at baseline, renal function improved independently of ART regimen, and mortality rates were similar in both treatment groups.TDF use did not attenuate renal function recovery or increase the mortality rate in patients with renal dysfunction. Further studies are needed to determine the role of routine renal function monitoring before and during ART use in Africa.

Glomerular Dysfunction and Associated Risk Factors over 4–5 Years following Antiretroviral Therapy Initiation in Africa

The aim of this study was to investigate long-term renal function in HIV-infected adults initiating antiretroviral therapy (ART) with a CD4(+) T-cell count < 200 cells/mm³ in Africa. This was an observational analysis within the DART trial randomizing 3,316 adults to routine laboratory and clinical monitoring (LCM) or clinically driven monitoring (CDM). Serum creatinine was measured pre-ART (all ≤ 360 μmol/l), at weeks 4 and 12, then every 12 weeks for 4-5 years; estimated glomerular filtration rate (eGFR) was determined using the Cockcroft-Gault formula. We analysed eGFR changes, and cumulative incidences of eGFR< 30 ml/min/1.73 m² and chronic kidney disease (CKD; <60 ml/min/1.73 m² or 25% decrease if <60 ml/min/1.73 m² pre-ART; confirmed >3 months). At ART initiation, median CD4(+) T-cell count was 86 cells/mm³; 1,492 (45%) participants had mild (60-< 90 ml/min/1.73 m²), 237 (7%) moderate (30-<60 ml/min/1.73 m² and 7 (0.2%) severe (15-<30 ml/min/1.73 m²) decreases in eGFR. First-line ART was zidovudine/lamivudine plus tenofovir (74%), abacavir (9%) or nevirapine (17%). By 4 years, cumulative incidence of eGFR<30 ml/min/1.73 m² was 2.8% (n=90) and CKD was 5.0% (n=162). Adjusted eGFR increases to 4 years were 1, 9 and 6 ml/min/1.73 m² with tenofovir, abacavir and nevirapine, respectively (P<0.001), and 4 and 2 ml/min/1.73 m² for LCM and CDM, respectively (P=0.005; 2 and 3 ml/min/1.73 m² to 5 years; P=0.81). On all regimens and monitoring strategies, severe eGFR impairment was infrequent; differences in eGFR changes were small, suggesting that first-line ART, including tenofovir, can be given safely without routine renal function monitoring.

Review: Meta-analysis of the effects of lithium usage on serum creatinine levels

There is conflicting evidence concerning lithium's effect on renal function. The aim is to clarify whether lithium affects kidney function and at what stage of treatment any effect may occur. Systematic review identified 23 studies split into three groups on which meta-analysis was performed to identify the following: A) lithium's effect on renal function in cross-sectional case-control studies, B) studies of renal function before and after commencement on lithium, C) studies of longer term effect in those already established on lithium therapy. Group A showed a statistically significant increase of 5.7 μmol/L in creatinine in the study population compared with controls. Group B showed a non-statistically significant rise in creatinine (2.9 μmol/L) after a mean follow-up of 86 months. Group C showed a statistically significant increase in creatinine of 7.0 μmol/L over a mean duration of 64 months. An increase in creatinine of an average of 1.6 μmol/L/year on lithium was also identified in this group. Any lithium-associated increase in serum creatinine is quantitatively small and of questionable clinical significance. However, routine renal function monitoring of patients on lithium is essential.

Serum cystatin C is a suitable marker for routine monitoring of renal function in pediatric cancer patients, especially of very young age

Monitoring renal function is crucial in children undergoing chemotherapy. To date, a combination of routine serum creatinine (SCR) monitoring with occasional determination of creatinine clearance ratio (CCR) is widely used as clinical standard for this purpose. Both methods have their limitations regarding diagnostic value (SCR) or practicability (CCR), especially in young children. Diagnostic alternatives, such as glomerular filtration rate (GFR) estimation formulas have not been proved to be superior. The aim of the study was to evaluate whether serum cystatin C (CysC) may have a diagnostic impact on pediatric patients. CysC, SCR, several GFR estimation formulas (Counahan-Barratt, Ghazali-Barratt, Schwartz, Shull, Traub), and CCR were studied in 80 pediatric cancer patients (age range: 0.17-17.9 years) during their chemotherapy. Special attention was given to children under the age of 3 in whom accurate urine collection for CCR is difficult. All parameters correlated similarly well with CCR. Total accuracy was 66% and 67% for CysC and SCR, respectively. In very young children (<3 years), correlation with CCR was for CysC r = -0.74 with an area under the curve (AUC) of 0.646, and for SCR r = -0.27 with AUC = 0.594. Total accuracy was 60% for CysC, 50% for SCR. CysC represents a suitable marker for monitoring renal function in pediatric cancer patients. In young children (<3 years), CysC may have a better diagnostic value than SCR. Future studies should show if CysC can improve renal monitoring by replacing SCR, especially in very young children.

Acute interstitial nephritis due to mesalazine

A case of mesalazine-induced acute interstitial nephritis (AIN) in a 41-year-old patient with ulcerative colitis (UC) is reported here. Clinical symptoms such as fever and arthralgia, and laboratory findings such as eosinophilia and renal failure suggested AIN, which was confirmed by biopsy. With withdrawal of mesalazine and intravenous methylprednisolone the patient's renal function was recovered. It is observed that early discontinuation of mesalazine is associated with amelioration of interstitial nephritis in most patients, so the recommendation is that patients receiving mesalazine should undergo routine monitoring of renal function. Delayed diagnosis may lead to permanent renal function impairment.

Review article: interstitial nephritis associated with the use of mesalazine in inflammatory bowel disease.

5-Aminosalicylic acid (5-ASA) has replaced sulphasalazine as first line therapy for mild to moderately active inflammatory bowel disease and is widely used. A number of reports have linked oral 5-ASA therapy to chronic tubulo-interstitial nephritis and this relationship is now well established. Despite increasing recognition of the potential for this serious adverse event, guidelines for monitoring renal function in patients prescribed 5-ASA preparations are not widely employed. Whilst the incidence of this adverse event in the population of patients with inflammatory bowel disease treated with mesalazine is low, the morbidity in an affected individual is high with some cases progressing to end-stage renal disease. Routine monitoring of renal function is simple and inexpensive and could prevent this outcome. Based on the available data, serum creatinine should be estimated prior to commencing treatment, monthly for the first 3 months, 3-monthly for the next 9 months, 6-monthly thereafter and annually after 5 years of treatment.

Nephrotoxicity following carboplatin use in children: Is routine monitoring of renal function necessary?

Carboplatin is an effective chemotherapeutic agent against many solid tumours. Although it is thought to be less nephrotoxic than its precursor cisplatin, current paediatric treatment protocols require regular monitoring of renal glomerular function during and after carboplatin use. Because accurate assessment of renal function in children requires measurement of isotope-clearance glomerular filtration rates (GFRs), routine monitoring is costly and time consuming. We studied 26 paediatric patients who were receiving chemotherapy that included 500-600 mg/m2 of carboplatin per course. 51Cr-EDTA GFRs were measured initially and after one to seven courses (median four). There was no measurable difference between renal function before and after carboplatin (P = 0.8). Our study shows that routine monitoring of renal glomerular function is unnecessary. Carboplatin use in patients who have had unilateral nephrectomy as part of their treatment is also discussed. Paediatric oncology literature concerning nephrotoxicity and carboplatin is reviewed.