The authors regret that errors occurred in final sentence of the last paragraph in the Results and discussion section and in Fig. 7 on page 176. The 24 h urinary DHA excretion in the three patients was erroneously reported as 816, 1327 and 1649 mg, respectively, both in the text and in Fig. 7. In addition, the urinary concentration of DHA was presented as the values measured in diluted urine samples which may cause ambiguity. The 24 h urinary DHA excretion values have been corrected, both in the text and in Fig. 7. Furthermore, the reported DHA concentration as measured in the diluted urine samples has been replaced by the actual concentration.
The corrected paragraph and Fig. 7 are provided below:
The clinical applicability of the assay was demonstrated by determining the concentration of DHA in 24 h urine samples from patients with APRT deficiency, diluted 1:15 (v/v) with 10 mM NH4OH. The urinary DHA concentration in the three patients was 45,320, 87,904 and 158,541 ng/mL and the 24 h urinary DHA excretion 81.6, 132.7 and 164.9 mg, respectively, suggesting a highly variable excretion rate between patients (Fig. 7).
The authors would like to apologise for any inconvenience caused.