Epidemiological and clinical profiles of CKD patients at first referral of a single nephrology outpatient clinic


The aim of the study is to investigate the baseline epidemiological and clinical profiles of patients at first referral to an outpatient nephrology clinic.

Case studies and methods

Cross-sectional study of all outpatients newly referred to a nephrology clinic over 12 months. A total of 282 patients was examined (64.9% males), mean age 64.5±17.8 years (13-95 years, modal value 72) ( Fig. 1 ).


Sixty-six percent of patients were referred by a primary care physician, 27% by an internist (diabetologist) and 7% for nephrologic follow-up after hospitalization (Fig. 2). Referral indications included renal impairment (60%), abnormalities of urinalysis (26%), and morphological alterations (16%) (Fig. 3). Serum creatinine and urinalysis had been determined prior to referral in 252/282 and 142/282 patients, respectively. Seventy-two % of patients had hypertension, 39% heart disease, 31% arterial-vascular disease, 27% diabetes, 32% urologic disease and 23% malignancies (mean number of comorbidities 3.2±2.0) (Fig. 4). Serum creatinine ranged 0.43-4.91 mg/dl, mean 1.48±0.68, and the eGFR (MDRD simplified formula) ranged 9.6-162.0, mean 57.2±28 ml/min/1.73m²; CKD stage 1: 12.7%; stage 2: 23.8%; stage 3a: 24.2 %, stage 3b 25.8%, and CKD stages 4&5: 13.5% (Fig. 5). Fourty-two%of patients, classified as CKD stage 2 or 3a(GFR <90->45 ml/min/1.73m2), had a normal renal function after adjustement of eGFR to their age, assuming a reduction of 1 ml/min/1.73m2 per year over the age of 40 years. Abdominal ultrasounds had been performed on 186/282 patients. Renal dimensions were measured only in 43%. Thirty % had abnormalities of echogenicity, 36.6% cysts, 7.5% stones, 5.4% focal space-occupying lesions and 5.4% urinary tract dilation.


The majority of patients are referred to a nephrology clinic by their doctor, due to impaired eGFR, often without urinalysis. They are elderly patients, with a high incidence of arterial hypertension and cardiovascular and metabolic comorbidities. Possibly, many aged patients are misclassified for CKD stage, if eGFR is not adjusted to age.