07-08-2011, 07:17 PM
A 36 year old woman presents to the office for a routine follow up visit. Her past medical history is significant for recurrent urinary tract infections which are unrelated to sexual intercourse. She was initially managed on intermittent self-treatment with Trimethoprim-Sulfamethoxazole. However, in view of frequent episodes of UTI she was started on continuous Trimthoprim prophylaxis one week ago. She denies any fever or abdominal pain. She has not had dysuria or frequency or urgency over the last 5 days. Physical examination is normal. Laboratory investigations reveal a WBC count of 6.3k/µl with normal differential, Sodium 140meq/l, Potassium 4.0meq/l, Blood urea nitrogen 10mg% and Creatinine 1.4mg% . Her labs obtained 1 month ago show Blood urea nitrogen of 12mg% and creatinine of 0.7mg%. The most likely explanation for her increased creatinine?
A) Allergic Interstitial Nephritis
B) Acute Tubular Necrosis
C) Pyelonephritis
D) Decreased tubular secretion
E) Papillary necrosis
A) Allergic Interstitial Nephritis
B) Acute Tubular Necrosis
C) Pyelonephritis
D) Decreased tubular secretion
E) Papillary necrosis