Diuretics associated acute kidney injury: clinical and pathological analysis.

Objective: In order to evaluate the clinical and pathological characteristics of diuretics associated acute kidney injury (AKI) and its management.

Methods: We performed a retrospective study including 131 cases that diagnosed as diuretics associated AKI from 1 January 1999 to 1 January 2010 in Ruijin Hospital affiliated to Shanghai Jiao Tong University. Drug applications and its related clinical, laboratory and histological data were collected.

Results: The male to female ratio was 2:1. The proportion of ages <20 years, 20-40 years, 40-60 years and ≥ 60 years were 6.9%, 17.6%, 27.5% and 48.1% respectively. Most patients (96.2%) had at least one complication of which chronic kidney disease (CKD) occurred most frequently (72 in 131, 55.0%). We divided all the patients to diuretic group (N=131) and non-diuretic group (N=185) based on diuretics history. We found patients in diuretic group had higher rates of CVD (38.9% vs. 18.4%), hypertension (42.0% vs. 29.2%), CKD (55.0% vs. 27.0%) and DM (17.6% vs. 4.3%) than non-diuretic group. Of 131 diuretics associated AKI, 36 cases (27.5%) were caused by diuretics only, 39 cases (29.8%) were caused by the combination of diuretics and other drugs like antibiotics, contrast media, ACEI or NSAIDs, and 56 cases (42.7%) had other AKI risk factors such as operation, infection, acute heart failure or hepatorenal syndrome. In addition, our data suggested the severity of RIFLE classification and pathological injury of glomerular basement membrane was higher in large-dosage furosemide group (>=120 mg/d) than in low-dosage group (<120 mg/d). The most common lesion induced by diuretics was vacuolar degeneration of tubular epithelial cell. Logistic regression analysis showed predictors of all-cause mortality were age, gender, RIFLE classification when AKI onset. Age and RIFLE classification were predictive factor of non-complete recovery.

Conclusion: This article firstly focuses on diuretics associated AKI, whose onset was related to aging, primary diseases and diuretic dosage. The combination of diuretics with other drugs such as antibiotics, contrast media, ACEI, NSAIDs, etc. would synergistically induced AKI. The pathological lesion of diuretics associated AKI may be mostly manifested vacuolar degeneration of tubular epithelial cell. Aging, gender, severity of RIFLE classification may be predictive factors of all-cause mortality of diuretics associated AKI.