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Medline ® Abstracts for References 1-5

of 'Urine anion and osmolal gaps in metabolic acidosis'

1
TI
The use of the urinary anion gap in the diagnosis of hyperchloremic metabolic acidosis.
AU
Batlle DC, Hizon M, Cohen E, Gutterman C, Gupta R
SO
N Engl J Med. 1988;318(10):594.
 
We evaluated the use of the urinary anion gap (sodium plus potassium minus chloride) in assessing hyperchloremic metabolic acidosis in 38 patients with altered distal urinary acidification and in 8 patients with diarrhea. In seven normal subjects given ammonium chloride for three days, the anion gap was negative (-27 +/- 9.8 mmol per liter) and the urinary pH under 5.3 (4.9 +/- 0.03). In the eight patients with diarrhea the anion gap was also negative (-20 +/- 5.7 mmol per liter), even though the urinary pH was above 5.3 (5.64 +/- 0.14). In contrast, the anion gap was positive in all patients with altered urinary acidification, who were classified as having classic renal tubular acidosis (23 +/- 4.1 mmol per liter, 11 patients), hyperkalemic distal renal tubular acidosis (30 +/- 4.2, 12 patients), or selective aldosterone deficiency (39 +/- 4.2, 15 patients). When the data on all subjects studied were pooled, a negative correlation was found between the urinary ammonium level and the urinary anion gap. We conclude that the use of the urinary anion gap, as a rough index of urinary ammonium, may be helpful in the initial evaluation of hyperchloremic metabolic acidosis. A negative anion gap suggests gastrointestinal loss of bicarbonate, whereas a positive anion gap suggests the presence of altered distal urinary acidification.
AD
Department of Medicine (Nephrology Section), Northwestern University Medical School, Chicago, IL 60611.
PMID
2
TI
A modified classification of metabolic acidosis: a pathophysiologic approach.
AU
Halperin ML, Vasuvattakul S, Bayoumi A
SO
Nephron. 1992;60(2):129.
 
AD
PMID
3
 
 
Rose BD, Post TW. Clinical Physiology of Acid-Base and Electrolyte Disorders, 5th ed, McGraw-Hill, New York 2001. p.590.
 
no abstract available
4
TI
Is the urine anion gap a reliable index of urine ammonium excretion in most situations?
AU
Inase N, Ozawa K, Sasaki S, Marumo F
SO
Nephron. 1990;54(2):180.
 
AD
Department of Internal Medicine, Yokosuka Mutual Aid Hospital, Kanagawa, Japan.
PMID
5
TI
Value and determinants of urine anion gap.
AU
Oh M, Carroll HJ
SO
Nephron. 2002;90(3):252.
 
AD
Department of Medicine, State University of New York Health Science Center at Brooklyn, NY 11203, USA.
PMID