MP129IMPACT OF WARMING IN THE INCIDENCE OF LUPUS NEPHRITISIN SOUTH OF TUNISIA

Abstract

Introduction and Aims: Systemic lupus erythematous (SLE) is an autoimmune disease which affects multiple organs including kidneys. It is commonly known that sun exposure can induce and exacerbate SLE. The occurrence of lupus nephritis (LN) can be also influenced by temperature variation. The aim of this study is to determine the effect of the global warming on the incidence of LN in our population. Method(s): Our study is retrospective, including all patients with SLE which had a Kidney biopsy nephrology department for LN suspicion during the period from 1985 to 2015. We included only the first kidney biopsy. The maximal temperatures were obtained from registers of the meteociel site for sfax region. Result(s): We included 238 patients. Mean age at biopsy was 31years+/- 11 [7-63]. 86% of patients were women with sex ratio at 7. A history of SLE was found in 35 patients (15%). Kidney biopsy was indicated for abnormalities of the urinary sediment, especially microscopic hematuria in 105 cases ( 45 %), acute kidney failure in 26 cases( 11,15%) and nephrotic syndrome in 13 cases (5,57%). Mean proteinuria was 4 g/day. Mean serum parotids level was 59 g/l +/- 11g/l and mean serum albumin level was 26 g/l +/-9,71g/l. Mean serum creatinine level was 153mumol/l [35-1400]. Frequency peaks were mainly observed at years: 2001 with 19 cases, 2002 with 16 cases, 2007 with 21 cases, 2009 with 19 cases and 2010 with 15 cases. These peaks were corresponding to high annual maximal temperatures observed in Sfax which are respectively: 25, 8degreeC, 25, 9degreeC, 25, 2degreeC, 24, 9degreeC and 25degreeC (fig1). Conclusion(s): Incidence of LN was very low before 1995 probably because of minor access to care in the eighties and early nineties. The incidence is quietly constant after this data with peaks mainly at 2001, 2002, 2007, 2009 and 2010. These peaks can be explained by high temperature in these years, compared with maximal annual temperatures in previous years. In literature, the ultraviolet light exposure has been implicated not only in cutaneous manifestations but also as possible environmental factor for SLE susceptibility, progression and relapses. The global warming effects are more likely significant on renal impairment also in SLE. It has been demonstrated that patients with regular use of sunscreen had significantly lower renal involvement. Therefore, sun exposure should be avoided in patients with LN, especially in high temperature periods. (Figure Presented).