2009 Southern Regional Meeting Abstracts

Purpose of Study: Heparin has been known to occasionally cause eosinophilia. However, there is no reported case in the literature of interstitial nephritis secondary to heparin.
We hereby report the first case of heparin-induced allergic interstitial nephritis.
Methods Used: This is a case report.
Summary of Results: The patient is a fifty-one year old African-American man with a history of diabetes mellitus type 2, hypertension, diabetic nephropathy with nephrotic syndrome and chronic kidney disease, non-adherent to all medications, who presented to the hospital with hypertensive urgency and worsening leg swelling. His blood pressure was adequately controlled with oral lisinopril, labetalol, nifedipine and furosemide and he was placed on unfractionated heparin for deep venous thrombosis prophylaxis. After remaining stable for a few days after admission, the serum creatinine began to rise and peaked at 6.5 mg/dl on the sixteenth hospital day from 4.5 mg/dl at admission. The eosinophil count, which had been normal at admission, also rose, parallel to the serum creatinine, to a peak of 18%. Gallium-67 citrate scintigraphy demonstrated bilateral symmetrical uptake by both kidneys. Acute interstitial nephritis and drug-induced eosinophilia were suspected and heparin was discontinued. All other medications were unchanged. The serum creatinine and eosinophilia began to trend down in twenty-four hours. On follow-up in two weeks, the serum creatinine stabilized close to baseline and eosinophilia had completely resolved.
Conclusions: Heparin can cause acute interstitial nephritis along with eosinophilia. On the Naranjo adverse drug reaction probability scale, this is a probable reaction. Since heparin is one the most commonly used medications used in hospitalized patients, it is important to recognize this serious adverse event in the appropriate clinical context.