The evaluation of acute interstitial nephritis begins with a medical history and physical examination.

Physical findings in someone with acute interstitial nephritis may include:

• Confusion
• Lethargy:
• A condition of excessive sleepiness or drowsiness.
• Dry skin
• Pale skin due to anemia
• Loss of body muscle
• Swelling of the feet or legs
• Swelling of the face (particularly around the eyes)
• Abnormal enlargement of the liver
• High blood pressure

Blood and urine tests are required to make the diagnosis of acute interstitial nephritis.

Tests that may be used to evaluate acute interstitial nephritis include:

• Serum calcium level
• Serum phosphate level
• Complete blood count
• Erythropoietin blood levels
• Kidney profile: includes sodium and potassium levels
• Urinalysis
• 24 hour urine for creatinine clearance

Additional tests that may be used to evaluate the kidney include:

• Renal scan:
• Gallium scan (nuclear scan) of the kidneys may aid in the diagnosis of this condition.
• Abdominal CT scan
• Intravenous pyelogram
• Kidney biopsy
• MRI scan of the abdomen
• Ultrasound of the abdomen
• Renal arteriogram