Clinicopathological and epidemiological analysis of amyloidosis in Turkish patients.

BACKGROUND: The aim of the present study was to assess the correlation of immunohistochemical subtyping with clinical diagnosis in order to achieve useful epidemiological data regarding amyloidosis in Turkish patients. METHOD: We carried out immunohistochemical studies on 128 biopsies from various sites of 111 patients with biopsy-proven amyloidosis and, based on the results, classified the patients. We assessed the correlation of immunohistochemical subtype with clinical diagnosis and gathered epidemiological data. RESULTS: The sites most biopsied were kidney and rectum, followed by the testicle, liver, small intestine and bladder. Amyloid deposits showed positive staining with a single antibody in 120 biopsies. Pure amyloid A (AA) positivity was seen in 113 biopsies; six biopsies were positive for amyloid lambda (AL) and one for beta2-microglobulin (beta2MG). The clinical diagnoses of 81 patients (98 biopsies all AA positive) were suggestive of familial Mediterranean fever (FMF). Also AA positive were eight patients with tuberculosis, seven patients with rheumatoid arthritis, four patients with bronchiectasis and one patient with Crohn's disease. The biopsies from seven patients clinically suspected to have plasma cell dyscrasias were AL positive. One patient undergoing haemodialysis was beta2MG positive. Two patients without definite diagnoses showed double or triple positivity, which could not be interpreted and classified immunohistochemically. CONCLUSIONS: This study demonstrates that the predominant association of AA amyloidosis is with FMF. It also suggests that the routine immunohistochemical study of patients with amyloidosis who are of certain ethnic backgrounds suffices for classifying the subtype of amyloid fibril protein and the related disease.

Oxidative stress and antioxidant status in elderly diabetes mellitus and glucose intolerance patients.

Increased oxidative stress and impaired anti-oxidant defense have been suggested as contributory factors for initiation and progression of complications in diabetes mellitus. Aging itself has been shown to be along with increased oxidative stress and lower anti-oxidant defense. We aimed at investigating oxidative stress and anti-oxidant enzymes in 61 elderly subjects. Fifteen healthy individuals (group 1, mean age 72.2 +/- 5.13), 13 glucose intolerant patients (group 2, mean age 71.7 +/- 4.9), 19 patients with type 2 diabetes mellitus (T2DM) without any complication (group 3, mean age 70.0 +/- 6.0), and 14 patients with T2DM with at least one complication (group 4, mean age 69.8 +/- 4.7) were included in the study. Whilst plasma levels for malondialdehyde (MDAP) and erythrocyte malondialdehyde (MDAE) were measured as markers of oxidative stress, activity of erythrocyte superoxide dismutase (SOD), glutathion peroxidase (GSH-Px), and catalase (CAT) were taken as markers of oxidative defense system. MDAP level was significantly elevated in group 4 (P = 0.001). MDAE was elevated in patients with T2DM, particularly in group 4, however, the difference between the groups was of borderline significance (P = 0.07). Whilst CAT was elevated in groups 3 and 4 compared to control subjects (P = 0.025 and 0.002, respectively), no difference was found for SOD between the groups. GSH-Px activity was found to be increased in groups 2, 3 and 4, it did not reach statistical significance (P = 0.106). There were significant correlations between CAT and MDAE (P < 0.0001, r = 0.056) and MDAP (P = 0.016, r = 0.306). These results suggest that there was an increased oxidative stress in elderly diabetics, however, this is not due to reduced erythrocyte antioxidant defense potential but, rather, increased free radical production possibly due to hyperglycemia.