Iron deficiency in chronic kidney disease patients with diabetes mellitus.

BACKGROUNDS: Iron deficiency has been studied extensively in patients with chronic kidney disease on hemodialysis therapy. However, few studies looked at iron treatment in the non-dialysis chronic kidney disease population. METHODS: Five hundred and eighty patients were studied (247 were diabetic persons). Patients were divided into 4 groups: non-diabetic subjects without CKD, non-diabetic ones with GFR < 60 mL/min, diabetic persons without CKD and diabetic ones with GFR < 60 mL/min). Iron deficiency was diagnosed when serum ferritin level was <100 mg/dl. It was defined as diminished iron availability when ferritin was above 100 mg/dl and serum transferrin saturation (TSAT) was <20%. RESULTS: Anemia was more frequent in the diabetic CKD patients group (52.4%, p < 0.001). Anemia prevalence was also higher in all CKD patients as well as in diabetic patients compared with non-diabetic ones. Iron deficiency was more frequent in diabetic patients. Among CKD diabetic patients the prevalence of iron deficiency was higher than in non-diabetic CKD ones. Diminished iron availability prevalence was higher in non-diabetic patients. Logistic regression analysis showed that only sex and diabetes mellitus were independently associated with iron deficiency. CONCLUSIONS: Anemia was more common in diabetic CKD patients. Diabetes mellitus was independently associated with iron deficiency. Surprisingly, diminished iron availability was not more frequent in diabetic patients. The physio-pathological mechanisms that could explain these findings remain to be elucidated.

A comparison of cystatin C concentrations between patients with chronic interstitial nephritis and glomerular diseases.

AIMS: Cystatin C have shown to be a renal function parameter with higher sensitivity and specificity than serum creatinine. In tubular diseases, cystatin C degradation and an increase in its urinary elimination would be observed. We have tried to define if different kinds of kidney diseases may significantly affect the serum levels of cystatin C. DESIGN AND METHODS: Four hundred and four patients were studied: 249 men and 155 women, mean age was 64.3±10.1 years. Patients were classified into three groups: (1) Chronic interstitial nephropathy (CIN), (2) Glomerular nephropathy (GN), and (3) Non- CKD patients (control). GFR was estimated though the CKD-EPI equation and the Hoek formula. RESULTS: Median of serum creatinine levels was higher in CIN group than in GN and control groups. Median cystatin C levels were lower in control group compared with CIN and GN groups. No significant differences were found between CIN group and GN group. Nevertheless, the cystatin/creatinine rate was lower in the CIN group patients (0.94, 0.81-1.11) than in the GN group (1.02,I 0.85-1.25) as well as the control group (1.02, I 0.88-1.20). The cystatin C-estimated GFR/creatinine-estimated GFR rate was higher in the CIN group (1.18, 1.03-1.36) than in the GN patients (1.03, 0.88-1.21) and control ones (1.07, 0.88-1.20). CONCLUSIONS: Patients with CIN had lower serum levels of cystatin C defined as cystatin C/creatinine rate when they were compared with GN subject and control ones. In the same way, the index between cystatin C-estimated GFR and creatinine-estimated GFR was higher in CIN patients.