Table 1.

Urine keratan sulfate (KS) and glycosaminoglycan (GAG) measurements from 25 MPS IVA patients

Age (Yr)	Total urine GAGs (mg/mmol crnn)	Urine KS (μg/mg crnn)
2	27.21 (<24)	46.51 (<9.6)
2	30.39 (<24)	48.14 (<9.6)
2	28.32 (<24)	61.51 (<9.6)
3	33.80 (<16)	30.68 (<9.6)
3	46.02 (<16)	44.62 (<9.6)
4	16.70 (<16)	25.83 (<9.6)
5	19.75 (<16)	27.13 (<9.6)
5	26.45 (<16)	38.36 (<9.6)
5	13.68 (<16)	38.03 (<9.6)
6	22.02 (<12)	26.32 (<6.2)
6	30.89 (<12)	37.66 (<6.2)
6	10.71 (<12)	46.48 (<6.2)
6	20.08 (<12)	33.07 (<6.2)
6	25.35 (<12)	18.00 (<6.2)
6	25.33 (<12)	21.98 (<6.2)
7	11.01 (<12)	21.31 (<6.2)
7	21.51 (<12)	41.67 (<6.2)
7	24.42 (<12)	41.13 (<6.2)
7	25.89 (<12)	51.04 (<6.2)
9	26.55 (<12)	26.79 (<6.2)
10	12.44 (<12)	12.64 (<6.2)
10	9.57 (<12)	13.14 (<6.2)
10	20.92 (<12)	33.79 (<6.2)
14	7.57 (<6.5)	7.09 (<5.8)
>15	12.12 (<6.5)	12.34 (<2.2)

Values in parentheses are the appropriate age-specific upper limit of the reference range and patient values within the normal range are in bold font. Total GAGs were measured by DMB incorporation and keratan sulfate by LC-MS/MS. All 25 samples had elevated urine KS but only 21/25 (83%) had elevated total GAGs