Measurement of 4-hydroxyphenylacetic aciduria as a screening test for small-bowel disease.

We evaluted measurement of urinary 4-hydroxyphenyl acetic acid as a potential screening 
method for small-bowel disease and bacterial overgrowth syndromes in 360 unselected 
acutely ill infants and children. Control data were obtained on 120 
healthy children, ages 1.5 to 15 years, from a general medical 
practice, 48 healthy infants, ages one to five years, from local 
day nurseries, and 150 healthy babies, ages less than one to 
eight days. Comparative data were from 300 acutely ill hospitalized babies 
and children, ranging in age from less than one day to 
15 years and without clinical evidence for small- bowel disease and 
bacterial overgrowth syndrome. No false-negative results and only 2% false-positive results 
were observed. Among the 10 patients whose urinary excretion of the 
analyte was considered to be abnormal were patients with Giardia lamblia 
infestation, ileal resection with blind loop, and other diseases of the 
small intestine associated with bacterial overgrowth. We conclude that measurement of 
4-hydroxyphenylacetic acid excretion is useful in screening for such diseases. 