Summary

Background: Amyloidosis of familial Mediterranean fever (FMF) may lead to end-stage renal failure, culminating in kidney transplantation. Since amyloidosis is prompted by high serum amyloid A (SAA) levels, increased SAA is expected to persist after transplantation. However, no data are available to confirm such an assumption.

 Objectives: To determine SAA levels in kidney-transplanted FMF-amyloidosis patients and evaluate risk factors for the expected high SAA levels in this patient group.

Methods: SAA, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) values were obtained from 16 kidney-transplanted FMF-amyloidosis patients, 18 FMF patients without amyloidosis and 20 kidney-transplanted patients with non-inflammatory underlying disease. Demographic, clinical and genetic risk factors evaluation was based on data extracted from files, interviews and examination of the patients.

Results: SAA level in FMF patients who underwent kidney transplantation due to amyloidosis was elevated with a mean of 21.1 ± 11.8 mg/L (normal ≤ 10 mg/L). It was comparable to that of transplanted patients with non-inflammatory disorders, but tended to be higher than in FMF patients without amyloidosis (7.38 ± 6.36, P = 0.08). Possible risk factors for the elevated SAA levels in kidney transplant patients that were excluded were ethnic origin, MEFV mutations, gender, age and disease duration.

Conclusions: Kidney-transplanted patients with FMF-amyloidosis and with other non-FMF causes displayed mildly elevated SAA levels, possibly resulting from exposure to foreign tissue rather than from various FMF-related factors.