PURPOSE: To investigate whether the adenosine antagonist theophylline reduces the incidence of contrast material-induced nephropathy (serum creatinine level increase of at least 0.5 mg/dL [44.2 mmol/L] in 48 hours) in high-risk patients who have chronic renal insufficiency and have received at least 100 ml of contrast medium.
MATERIALS AND METHODS: One hundred patients with serum creatinine levels of 1.3 mg/dL (114.3 mimol/L) or greater were randomly assigned to intravenously receive 200 mg theophylline or saline 30 minutes before administration of 100 mL or more of low-osmolarity contrast medium arterially (72 [72%] patients) or intravenously (28 [28%] patients).
RESULTS: Patients receiving theophylline and control subjects were comparable with regard to risk factors for contrast-induced nephropathy such as mean serum creatinine level before contrast medium administration (2.07 mg/dL � 0.94 [SD] [182.9 (mmoI/L � 83.1 ] vs 1.92 mg/dL � 0.76 [169.7 mmol/L � 67.2], respectively), amount of contrast medium (196.5 mL � 84.1 vs 216.6 mL � 95.0, respectively), and diabetes prevalence. Theophylline prophylaxis significantly reduced the incidence of contrast material-induced nephropathy (4% vs 16%; P = .046). With theophylline, the mean serum creatinine level decreased nonsignificantly 12 (1.98 mg/dL � 0.77 [175.0 mmol/L � 68.1]; P = .09), 24 (1.97 mg/dL � 0.75 [174.1 mmol/L � 68.1]; P = .99), and 48 (1.94 mg/dL � 0.77 [171.5 (mmol/L � 68.1]; P -.99)0.94 mg/dL � 0.77 [171.5 (mmol/L � 68.1]; P = .99) hours after contrast medium administration. With a placebo, serum creatinine level significantly increased 24 hours after contrast medium administration (2.01 mg/dL � 0.89 [177.7 (mmol/L � 78.7]; P = .006). Urinary N-acetyl-p-glucosaminidase level did not change with theophylline administration but significantly (P = .034) increased 24 hours after contrast medium administration with the placebo.
CONCLUSION: Prophylactic administration of 200 mg theophylline reduces the incidence of contrast material-induced nephropathy in patients with chronic renal insufficiency.