Acute renal failure (ARF) is a clinical syndrome characterized by a rapid deterioration in renal function over a period of hours or days. Since elderly patients are more susceptible to renal ischemia, they are more prone to develop acute renal failure than younger patients Citation[[1]]. The functional renal alterations associated with the aging process, the presence of intercurrent illnesses such as hypertension, cardiovascular disease, arteriosclerosis, diabetes mellitus, chronic liver disease, obstructive nephropathy; the frequent use of multiple drug therapy and dehydration predispose geriatric patients to an increased risk of acute renal failure Citation[[2]], Citation[[3]].
In a retrospective study, we analyzed the etiology, course and outcome of ARF in elderly patients admitted or referred to our Nephrology department. All patients of ARF over 65 years admitted to our renal unit during the period January 1996 to January 2001 were included in the study. Patients with past history of renal disease and those with acute or chronic renal failure were excluded. A total of 68 patients (46 males and 22 females: mean age 69.4 ± 4.3, ranging between 65–93 years) were investigated. ARF was clinically diagnosed when serum creatinine increased to more than 265 µmol/l acutely with or without oliguria. Oliguria was defined as a urine output of less than 500 ml/24 h.
All patients were subjected to investigations, which included blood serum nitrogen, serum creatinine, serum electrolyte levels, hematological profile, urinalysis and renal ultrasonography. Percutaneous renal biopsies were performed in 3 patients. The indications for renal biopsy were prolonged oliguric phase and the clinical suspicion of an illness other than acute tubular necrosis. The management of the patients included correction of fluid and electrolyte disorders, treatment of infections and dialytic support in the form of hemodialysis whenever needed. Two patients with crescentic glomerulonephritis received immunosuppressive therapy. The patients were investigated for the underlying etiology, duration of ARF, need for dialytic support, complications and outcome.
Among 68 geriatric patients, 38 (56%) developed ARF due to surgical conditions, while in 30 patients (44%), ARF was due to medical causes. Obstruction due to prostatic hypertrophy or carcinoma and complications following prostate surgery were the main underlying factors of surgical ARF in 28 patients (74%). ARF due to other urological or gynecological neoplasms comprised 26% of surgical causes of ARF.
The most frequent causes of ARF due to medically related problems were drugs and sepsis in elderly patients (24 patients, 80%). A combination of aminoglycoside antibiotics and nonsteroidal anti-inflammatory drugs contributed to ARF in 11 patients (16.2%). In 10 patients, sepsis and the use of nephrotoxic drugs were the cause of ARF (14.7%). Nonsteroidal anti-inflammatory drugs alone were responsible for ARF in 3 cases (4.4%). Radiocontrast agents were the main etiological factor in 2 patients (2.9%). Antibiotics alone led to ARF in 1 patient (1.5%).
Percutaneous renal biopsy showed diffuse crescentic glomerulonephritis in 2 patients (2.9%) and acute tubular necrosis in 1 patient (1.5%).
Hemodialytic support was given to 24 patients (35.3%). Mean duration for normalization of serum creatinine was 26.3 ± 5.2 days. A complete recovery of ARF was observed in 41 patients (60.3%). Eleven patients (16.2%) showed a partial recovery of renal function. displays the clinical characteristics of geriatric patients with ARF.
Table 1. Clinical Characteristics of Geriatric Patients with ARF
Ten patients (14.7%) became dialysis-dependent. The mortality in geriatric patients was 8.8% (6 patients). In 3 cases, mortality was attributed to cardiovascular disease. Two patients died of septicemia and one patient died of acute pancreatitis with ARF.
The results of our study show that age is not a particularly poor prognostic sign, and outcome seems to be within acceptable limits for elderly patients with ARF. Our study also shows that nephrotoxic drugs and dehydration represent common but avoidable causes of ARF in elderly patients.
REFERENCES
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- Macias Nuñez J.F., Sanches Tomero J.A. Acute Renal Failure in Old People. Renal Function and Disease in the Elderly, J.F. Macias Nuñez, J.S. Cameron. Butterworths, London 1984; 461–484
- Lameire N., DeKeyzer K., Pauwels W. Acute Renal Failure in the Elderly. Geriatric Nephrology, D.G. Oreopoulos. Martinus Nijhoff, Boston 1986; 103–116