Mizoribine therapy for patients with lupus nephritis: the association between peak mizoribine concentration and clinical efficacy.

The clinical efficacy of mizoribine (MZR; 4-carbamoyl-1-b-D-ribofuranosylimidazolium) in patients with lupus nephritis was investigated. Thirteen Japanese patients with biopsy-proved lupus nephritis were enrolled in this study. A change in global assessments score, total protein (TP) of serum, serum creatinine, creatinine clearance (Ccr), proteinuria, titers of serum anti-ds DNA antibody, C3, C4, and hemolytic complement activity (CH50) were examined. Following MZR treatment, the level of urinary protein decreased (P < 0.05), whereas the level of Ccr increased (P < 0.05). Moreover, the level of TP significantly increased from 5.5 g/dl to 6.3 g/dl (P < 0.01) and the level of C3 increased significantly (P < 0.01). However, there was no change in the levels of both C4 and CH50. The titer of anti-ds DNA antibody significantly decreased (P < 0.05). The dosage of prednisolone could be tapered from 24.8 mg to 14.9 mg daily during the period. The clinical effects associated with MZR concentration in the blood revealed that there was a significant correlation between the peak MZR blood concentration of more than 0.66 microg/ml and clinical improvement (P = 0.021). Our results suggest that an optimal MZR blood concentration was important for the treatment of lupus nephritis.

Outcome of patients with reactive amyloidosis associated with rheumatoid arthritis in dialysis treatment.

The aim was to analyze the clinical outcome of a group of 51 patients diagnosed with systemic amyloidosis associated with rheumatoid arthritis who received hemodialysis (HD) as renal replacement therapy. We monitored the clinical course of the disease and factors that could influence survival. Determination of the onset of the underlying disorder was made retrospectively by reviewing the patient's chart when a diagnosis of amyloid was confirmed. During a 96.9 person-year follow-up, 42 patients died. Survival of these 51 patients from the initiation of HD at 251 days was 50%. Poor prognosis in amyloid patients was mainly due to a large number of sudden deaths immediately following HD therapy. Out of 51 patients 21 needed unplanned initiation of HD. The unplanned initiation was significantly associated with poor survival. Seventy-five percentile of creatinine clearance (Ccr) was 9.7 ml/min, and 75% of these patients who initiated HD had highly impaired renal functional states. These data indicated that amyloidotic patients with HD showed a high mortality rate; therefore, planned initiation of HD was highly recommended to improve the patient's survival. Particular attention was given to the Ccr levels, because the levels of serum creatinine may not be a useful marker for some patients with amyloidosis.