Research Article Urine Monocyte Chemoattractant Protein-1 and Lupus Nephritis Disease Activity: Preliminary Report of a Prospective Longitudinal Study Sabah Alharazy, 1 Norella C. T. Kong, 1 Marlyn Mohd, 2 Shamsul A. Shah, 3 Arbaiyah Ba’in, 1 and Abdul Halim Abdul Gafor 1 1 Nephrology Unit, Department of Medicine, Universiti Kebangsaan Malaysia Medical Centre, 56000 Kuala Lumpur, Malaysia 2 Department of Medical Microbiology & Immunology, Universiti Kebangsaan Malaysia Medical Centre, 56000 Kuala Lumpur, Malaysia 3 Department of Community Medicine, Universiti Kebangsaan Malaysia Medical Centre, 56000 Kuala Lumpur, Malaysia Correspondence should be addressed to Sabah Alharazy; sabah alharazy@yahoo.co.uk Received 23 January 2015; Revised 12 April 2015; Accepted 15 April 2015 Academic Editor: Ricard Cervera Copyright © 2015 Sabah Alharazy et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. his longitudinal study aimed to determine the urine monocyte chemoattractant protein-1 (uMCP-1) levels in patients with biopsy-proven lupus nephritis (LN) at various stages of renal disease activity and to compare them to current standard markers. Methods. Patients with LN—active or inactive—had their uMCP-1 levels and standard disease activity markers measured at baseline and 2 and 4 months. Urinary parameters, renal function test, serological markers, and renal SLE disease activity index-2K (renal SLEDAI-2K) were analyzed to determine their associations with uMCP-1. Results. A hundred patients completed the study. At each visit, uMCP-1 levels (pg/mg creatinine) were signiicantly higher in the active group especially with relapses and were signiicantly associated with proteinuria and renal SLEDAI-2K. Receiver operating characteristic (ROC) curves showed that uMCP-1 was a potential biomarker for LN. Whereas multiple logistic regression analysis showed that only proteinuria and serum albumin and not uMCP-1 were independent predictors of LN activity. Conclusion. uMCP-1 was increased in active LN. Although uMCP-1 was not an independent predictor for LN activity, it could serve as an adjunctive marker when the clinical diagnosis of LN especially early relapse remains uncertain. Larger and longer studies are indicated. 1. Introduction Lupus nephritis (LN) contributes to signiicant morbidity and mortality in patients with systemic lupus erythematosus (SLE) [1, 2]. Renal biopsy is the gold standard for diagnosis of LN. However, repeated biopsies are not always practical in real life practice especially in patients with frequent relapses or in those with associated severe haematologic or cerebral manifestations. Moreover, renal biopsy is a relatively invasive procedure and is associated with a signiicant albeit small risk, particularly in those patients who may have undiagnosed coagulopathy, for example, presence of antiphospholipid antibodies/antiphospholipid syndrome, or are on anticoagu- lants [3]. Active LN especially early lares/relapses oten respond to appropriate treatment with immunosuppressive agents. However, these drugs are themselves associated with signif- icant morbidity and even mortality whilst uncontrolled LN activity leads to chronic or end stage kidney disease (ESRD) and even death. Current standard laboratory markers such as proteinuria cannot always distinguish between active and inactive renal disease especially in patients with a recent history of LN [4]. hese tests also lack sensitivity and speciicity for the monitoring of LN activity especially early lares. Hence, it is essential to identify noninvasive new biomarkers that are able to predict renal lares/relapses as well as relect the severity of LN activity. hese biomarkers could be followed serially and may enable timely institution of Hindawi Publishing Corporation Autoimmune Diseases Article ID 962046