[Changes in fibronectin concentration during therapeutic plasmapheresis. Therapeutic effectiveness of selective removal of fibronectin in immune complex pathology].

Variation in the concentration of plasma fibronectin (FN) seen during 65 sessions of therapeutic plasmapheresis was studied in 20 inpatients with the following diagnoses: acute leukemias (4), paraproteinemic hemoblastoses (5), Sjögren's syndrome (2), protracted septic endocarditis (1), systemic lupus erythematosus (17), acute polyradiculoneuritis (1), multiple sclerosis (3). The patients' age ranged within 19 to 64 years. There were 10 men and 10 women. The concentration of FN in 218 plasma samples was measured by the ELISA. It was discovered that plasma of healthy donors contained 200 to 400 micrograms/ml FN (M +/- 1.5 sigma). Prior to plasmapheresis the glycoprotein content in all the patients was on the average within normal (300 micrograms/ml). After the session the concentration of FN decreased almost two-fold (130 micrograms/ml); after 6 hours it was 175 micrograms/ml on the average, whereas after 24-48 hours it reached the initial level. Repeated plasmapheresis sessions carried out once every 3-4 days did not lead to the depletion of the FN pool, since its level reached the initial one over the first 24-48 hours. Such a mechanism was unchanged regardless of the initial level of FN recorded in the patients blood (high, normal or low). No relationship was found between FN deficiency which developed after plasmapheresis and infectious complications. It is assumed that FN deficiency per se cannot be responsible for the patients' decreased resistance to infection. Three patients received a series of selective plasmapheresis. Sjögren's syndrome and immune complex vasculitis was diagnosed in one female patient, hemorrhagic vasculitis due to chronic hepatitis in another female patient, the third female patient manifested gammapathy with cryoglobulinemia.(ABSTRACT TRUNCATED AT 250 WORDS)