Internal Medicine

P1: SBT

0521779407-03 CUNY1086/Karliner 0 521 77940 7 June 7, 2007 19:6

Amyotrophic Lateral Sclerosis (ALS) Analgesic Nephropathy 117

Prognosis

■Mean survival is 3 years

■Only 25% of pts survive for 5 years

Analgesic Nephropathy And NSAID-induced ARF............

CHARLES B. CANGRO, MD, PhD and WILLIAM L. HENRICH, MD

history & physical

Classic Analgesic Nephropathy

■History of long term habitual use of combination analgesic prepa-

rations

■minimum total dose required unknown. Some suggest a cumulative

dose of 3 kg or a daily ingestion of 1 g per day for more than three

years

■female:male 6:1

■consider in any patient with chronic renal failure and a history of

multiple somatic complaints, chronic headaches, backache, etc.

■85% of patients deny heavy analgesic use on initial questioning

■cumulative ingestion of several kilograms of combination analgesics

(aspirin and phenacetin or its metabolite acetaminophen) associ-

ated with increased risk

■aspirin alone appears to pose little risk

■nonspecific : slowly progressive chronic renal failure

■present with increased creatinine

■anemia

■gastrointestinal symptoms

■may present with end stage renal disease

■flank pain and hematuria if papillary necrosis occurs NSAID –

Induced Acute Renal Failure

■most common with propionic acid derivatives (fenoprofen, ibupro-

fen and naproxen)

■may occur at any time after starting drug use (2 weeks–18 months)

■acute renal failure secondary NSIAD inhibition of renal prostag-

landin synthesis and subsequent intra-renal vasoconstriction

■sodium and water retention (presents as edema or hyponatremia)

■hypertension

■nephrotic-range proteinuria (80% of cases)

■hyperkalemia (low renin, Type IV RTA picture)

■papillary necrosis (due to ischemia of inner medulla)