Critical Care Medicine-Renal, Electrolyte and Acid Base Disorders>>>>>Diagnosis and Monitoring in Renal Failure
Question 2#

You are asked to consult on a previously healthy 68-year-old woman who presented with malaise and one episode of hematuria. She visited her primary care doctor 5 days ago for a “bladder infection” and was prescribed trimethoprim-sulfamethoxazole, which she has been taking. She is alert and oriented, and her physical examination is within normal limits. Her vital signs are normal. Her laboratory data are unremarkable except for elevated eosinophils, creatinine of 3 mg/dL, and urea 41 mg/dL.

What management should you pursue next?

A. Administer fomepizole
B. Discontinue trimethoprim-sulfamethoxazole
C. Administer 500 mL bolus of normal saline
D. Obtain a computed tomography (CT) abdomen/pelvis with intravenous (IV) contrast

Correct Answer is B

Comment:

Correct Answer: B

Treatment of AIN includes discontinuing the offending agent (question 2—choice B) or treating the underlying disease. In severe cases of biopsy- confirmed AIN, steroids can be administered. Answer A is incorrect because fomepizole is the treatment for ethylene glycol poisoning, not AIN. Her urea/creatinine ratio is less than 20, making prerenal cause unlikely, so fluid bolus would not be needed here. Also, CT scan with IV contrast would not be the best choice as there is no indication for this study, and IV contrast should be avoided in patients with AKI (answer D).

References:

  1. Praga M, Appel GB. Clinical Manifestations and Diagnosis of Acute Interstitial Nephritis. Retrieved from Uptodate. https://www.uptodate.com/contents/clinical-manifestations-anddiagnosis-of-acute-interstitial-nephritis.
  2. Roberts PR, Todd SR. Acute and chronic renal failure and management (including hemodialysis and continuous renal replacement. therapies). In: Comprehensive Critical Care: Adult. 2nd ed. USA: Society of Critcal Care Medicine; 2017:365-376:Chap 33.
  3. Kshirsagar AV, Falk RJ. Treatment of Acute Interstitial Nephritis. Retrieved from Uptodate. https://www.uptodate.com/contents/treatment-ofacute-interstitial-nephritis.
  4. Ronco P. Mechanisms of Immune Injury of the Glomerulus. Retrieved from Uptodate. https://www.uptodate.com/contents/mechanisms-ofimmune-injury-of-the-glomerulus.
  5. Sivilotti MLA. Methanol and Ethylene Glycol Poisoning. Retrieved from Uptodate. https://www.uptodate.com/contents/methanol-and-ethyleneglycol-poisoning.