Ȼɪɨј 6 − ɋɭɩɥеɦеɧɬ ȼɈЈɇɈɋȺɇИɌȿɌɋɄИ ɉɊȿȽɅȿȾ ɋɬɪаɧа 21 Dimitrijević J, et al. Vojnosanit Pregl 2002; 59(6 Suppl): 21−31. UDC: 616.61-002.5-091.8 STRU Č NI Č LANCI Lupus nephritis: histopathologic features, classification and histologic scoring in renal biopsy Jovan Dimitrijević * , Ljubica Đukanović ‡ , Zoran Kovačević † , Radovan Bogdanović § , Đoko Maksić † , Rajko Hrvačević † , Anastasija Aleksić † , Radomir Naumović ‡ , Dijana Jovanović ‡ , Goran Brajušković * , Ivica Milosavljević * Military Medical Academy, * Institute of Pathology, † Clinic of Nephrology, Clinical Center of Serbia, ‡ Institute for Urology and Nephrology, § Institute for Mother and Child Health of Serbia, Belgrade Lupus nephritis (LN) is one of the most significant manifestations in systemic lupus erythe- matosus (SLE), although in some cases there is no direct correlation among clinical, serologic and histologic findings. Therefore, renal biopsy and histopathologic classification by the ac- tivity and chronicity assessment of LN are considered necessary before the initiation of the treatment. In this paper 311 renal biopsies in patients with LN were analyzed and classified according to the WHO Classification published in 1974. Renal biopsy specimens were rou- tinely processed for standard analysis by light microscopy (LM), immunofluorescent (IF), and electron microscopy (EM). Biopsy findings were compared with the common clinical symp- toms. It is important to recognize that histopathologic lesions in the analyzed tissue might pre- cede the symptoms and clinical manifestations, and therefore are an important factor in the appropriate therapeutic approach. Histopathological assessment of the class of LN represents an important predictor in most patients because the lesions of LN class I and class II most of- ten have no progression and consequently do not require an aggressive treatment. Diffuse proliferative glomerulonephritis (class IV) as a severe form of renal lesion requires the appli- cation of high doses of corticosteroids and cytotoxic medicaments. The established quantitive indexes have significant predictive value. Activity index (AI) evaluates the presence of fresh inflammatory and potentially reversible lesions and chronicity index (CI) evaluate the pres- ence of irreversible glomerular lesions such as sclerosis, tubular atrophy, interstitial fibrosis, etc. High AI and low CI, particularly in the class IV of LN, suggest the necessity of an aggres- sive treatment of the inflammatory process aiming to preserve the renal function. High CI and low AI characterize irreversible sclerosing lesions, where an aggressive treatment is consid- ered unnecessary. Our experience suggests the necessity of introducing the new morphologic elements into the activity and chronicity scoring system which would correlate better the clini- cal symptoms. This should provide higher reliability of scoring, since it evaluates important elements in clinical-morphologic diagnosis of LN. Key words: lupus nephritis; kidney; biopsy; microscopy; microscopy, electron; microscopy, fluorescence; kidney failure, chronic. Introduction Renal involvement is frequent in systemic lupus erythematosus (SLE), with clinical evidence of the renal disease in approximately two thirds of patients, and with high prevalence in females and African-Americans. Renal biopsy has an important role in managing the patients with SLE. For the reliable evaluation of morphology and ac- tivity of the tissue lesion, the use of light microscopy (LM), immunofluorescence (IF) microscopy and electron