The pitfalls associated with urinary steroid metabolite ratios in children undergoing investigations for suspected disorders of steroid synthesis.

Background: Urinary steroid metabolite ratios may improve the diagnostic yield of potential disorders of steroid hormone synthesis.

Objectives: To investigate the range of ratios and their predictive value in children with suspected disorders of steroid synthesis.

Design And Methods: Twelve ratios were calculated on steroid metabolite data analysed by gas chromatography-mass spectrometry in urine samples collected between 2008-2010 from 93 children. Urine samples were also analysed in 252 children with no known endocrine concerns.

Results: Of the 252 controls, 115 (46%) were male with a median age of 10 yr (range 1 month,18.5 years). Of the 93 cases, 38 (41%) were male with a median age of 6.5 yr (1 day,18.5 yrs). Of these, 41 (44%) had at least one ratio greater than the 95% percentile for controls. The most frequently abnormal ratio, found in 18/93 (19%) cases was (THS/(THE + THF + 5αTHF)) suggestive of 11β-hydroxylase deficiency. Over this period, 8 (9%) children were subsequently diagnosed with a steroid hormone disorder; 4 with 21-hydroxylase deficiency, 2 with11β-hydroxylase deficiency and 2 with 5α-reductase deficiency. All except one of these children had at least 1 raised ratio.

Conclusions: Urinary steroid metabolite ratios in suspected disorders of hormone synthesis often exceed the reference range for normal children. The predictive value of steroid metabolite ratios in identifying a genetic abnormality may be condition specific and needs further study to improve its clinical utility.