Human albumin infusion for treating oedema in people with nephrotic syndrome

BACKGROUND: Oedema is a common clinical symptom in people with nephrotic syndrome and human albumin has been widely used in the treatment of oedema by increasing vascular volume and this inducing diuresis. It may be used with or without diuretics such as furosemide. However, the quantitative contribution of human albumin in treating oedema is not fully understood. If human albumin were found to be effective and safe in the treatment of oedema, it could help clinicians to develop therapeutic strategies to improve the management of diuretic resistance associated with nephrotic syndrome.

OBJECTIVES: This review aimed to examine the benefits and harms of human albumin infusion for treating oedema associated with nephrotic syndrome.

SEARCH METHODS: We searched the Cochrane Kidney and Transplant Register of Studies up to 23 June 2019 through contact with the Information Specialists using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs evaluating the effect of human albumin infusion compared with placebo or no intervention, human albumin with diuretics compared with diuretic alone, human albumin compared with diuretics and other treatments, clinical outcomes, death, quality of life, kidney function and adverse effects in people with nephrotic syndrome. We excluded cross-over studies but data for the first period was to be included if available.

DATA COLLECTION AND ANALYSIS: Standard methods of the Cochrane Collaboration were used. Two authors independently assessed eligibility, risk of bias, study quality and extracted data. We calculated mean difference (MD) for continuous data with 95% confidence intervals (CI). We assessed the certainty of the evidence using GRADE.

MAIN RESULTS: One study met our inclusion criteria (26 children with minimal change nephrotic syndrome) and 11 were excluded (nine cross-over studies, one where albumin was not used for nephrotic syndrome and one where authors did not state whether the children had oedema). Risk of bias for the included study was unclear for selection bias, high for performance and detection bias, low for attrition bias, and high for selective reporting. The included study compared albumin plus furosemide with an equal volume of dextrose. Of our prespecified outcomes, the authors reported clinical improvement as weight change, serum sodium and adverse outcomes (blood pressure). The authors reported a greater weight loss in the albumin treated group initially but no difference overall at 10 days. However, the data in the text and the figures were inconsistent so we could not confirm the authors statements (very low certainty evidence). It is uncertain whether albumin infusion improves serum sodium when compared with an equal volume of dextrose (MD 2.00 mEq/L, 95% CI -0.09 to 4.09), systolic blood pressure (MD 2.00 mmHg, 95% CI -3.52 to 7.52) or diastolic blood pressure (MD 2.00 mmHg, 95%CI -4.29 to 8.29). Death, quality of life, and kidney function were not reported.

AUTHORS' CONCLUSIONS: We identified only one small study that was relevant to our review, therefore we are unable to draw any conclusions regarding the use of human albumin with or without diuretics in nephrotic syndrome. More RCTs are needed.