[Chromosomal aberrations in lymphocytes of patients with systemic lupus erythematosus during cytostatic therapy]

To study cytogenetics of peripheral blood lymphocytes in patients with systemic lupus erythematosus (SLE) in the course of therapy with a selective immunodepressant sandimmun and universal cytostatic cyclophosphamide.

30 women with lupus-nephritis and nephrotic syndrome received sandimmun in a dose 2.5-7 mg/kg plus 10-20 mg prednisolone for a month with gradual lowering of sandimmun dose to 2.5-5 mg/kg and prednisolone to 0-10 mg/day. 10 patients with lupus-nephritis were given cyclophosphamide in a dose 1000 mg as a single intravenous drip once a month for 6 months in combination with 30-40 mg prednisolone for a month with the dose reduction to 20 mg/day. Sandimmun and cyclophosphamide effects on mutagenesis were studied in 72-120-h PHA-stimulated lymphocyte cultures. Chromosomal aberrations (CA) were assessed according to A.F. Zakharov's classification and proposals of International workshop in Melburn (1993).

Sandimmun therapy on day 14 did not increase CA frequency but led to appearance of "premature chromosome condensation phenomenon" (PCC). PCC diminished after one month of sandimmun therapy and disappeared after 3-6 months. Cyclophosphamide provoked a rise in the incidence of both chromatide aberrations and CA.

Sandimmun does not increase CA incidence in lymphocytes. On the contrary, it promoted the fall in this incidence while syclophosphamide stimulated CA and chromatide aberrations. This trend was observed till the end of cyclophosphamide administration.