Internal Medicine

P1: SBT

0521779407-02 CUNY1086/Karliner 0 521 77940 7 June 7, 2007 19:18

50 Acute Renal Failure

Acute Renal Failure....................................

MICHAEL J. RYAN, MD and RICHARD ZAGER, MD

REVISED BY MICHAEL J. RYAN, MD

history & physical

■Date onset of ARF

■Define clinical setting – Fever, malaise, arthritis, rash, cough, hemop-

tysis, rash, livedo reticularis, microinfarctions of distal digits

■Difficulty urinating, hesitancy, decreased stream, BPH

■Blood pressure

■Determine volume status

➣History of volume loss

➣Orthostatic changes in pulse and blood pressure

➣Central venous pressure as determined by neck veins

➣S3 gallop

➣Rales

➣Peripheral edema

➣Documented decreased weight or output > input

■Abdominal exam

➣Bladder palpable

➣Rectal/pelvic

Enlarged prostate, pelvic masses

tests

Laboratory

■Basic blood studies:

➣High BUN/creatinine ratio (>20) suggests prerenal ARF

➣but also seen with obstruction, steroids, GI bleed

■Basic urine tests:

■1. Urinalysis

➣Prerenal failure

➣Arterial occlusion

➣Post renal failure

Minimal findings (absence of protein, blood, leukocytes on

dip; absence of cells, casts in sediment)

➣AT N

Coarse granular and darkly pigmented (muddy brown) gran-

ular casts, intact tubular epithelial cells

➣Allergic interstitial nephritis

Pyuria, WBC casts, urine eosinophils