Systemic lupus erythematosus in Thai children: Clinicopathologic findings and outcome in 82 patients

Abstract

Objectives: To define the patterns of clinicopathologic findings and to identify the risk factors for renal failure and mortality of childhood-onset systemic lupus erythematosus (SLE) in Thailand. Material and Method: The study is a retrospective analysis of clinical manifestations, laboratory data, and pathologic findings, treatment modalities, and outcome of 82 patients with biopsy-proven lupus nephritis (LN) with disease onset between 1 January 1987 and 31 December 1997. All children developed these first manifestations at the age 13 years or under. Results: Sixty-four (78%) patients were females and eighteen (22%) were males (ratio female/male = 3.5:1). The patients were followed for a mean period of 53.6 months (range 1 -141). The mean age at disease onset was 9.2 years (range 2-12.6). Class-IV LN, observed in 40 (48.8%) patients, was the most frequent histopathology on initial renal biopsy. Less frequent findings were class-II (30.5%), V (14.6%), I (3.7%) and III (2.4%) LN. Based on the renal histopathology and clinical presentations, patients were treated with corticosteroids alone or in combination with azathioprine or with intravenous cyclophosphamide (CYC). Methylprednisolone pulses were given in patients with clinically more severe disease. Follow-up biopsies, performed in 12 patients, showed no change in 4 patients, and were progressive in 8 patients. On final clinical evaluation, 20 patients died, 65% died from serious infections, 15% from cardiopulmonary complications, and 10% from end stage renal disease. As the whole group, survival rates were 89% and 74% at 12 and 60 months, respectively. The 5-year patient survival in class-II, class-IV and class-V LN patients were 83%, 67% and 64%, respectively. Within the group of class-IV LN, the 5-year survival in the patients treated with intravenous CYC was significantly better than those receiving prednisolone with or without azathioprine. Five-year kidney survival rates from the time of diagnosis to the endpoints of terminal renal failure were 94% for the whole group, and 100%, 96%, 91% in the class-V, class-II, and class-IV group, respectively. Initial presence of hypertension, hematuria, renal insufficiency were independent factors significantly associated with lower patient survival probabilities. There was no association of either patient and kidney survival with gender, age, cytopenia, and autoantibody level. Conclusions: Infectious complications were the most common cause of morbidity and mortality in our pediatric patients with SLE. The immunosuppressive agents used to treat SLE seemed to be a major contribution to the patient survival. With judicious use of corticosteroid, intravenous CYC in severe SLE showed superior efficacy over oral prednisolone with or without azathioprine.