Reference levels for glucose-6-phosphate dehydrogenase enzyme activity in infants 7-90 days old in Taiwan.

BACKGROUND: Nationwide newborn screening for glucose-6-phosphate dehydrogenase (G6PD) deficiency has been implemented in Taiwan since 1987 and the G6PD enzyme activity levels were applied for diagnosis confirmation. As the reference value of G6PD enzyme activity was not available for infants aged 7-90 days, this study was performed to determine the enzyme level in different genotypes. METHODS: Between January 1, 2016 and June 30, 2017, 410 term infants aged 7-90 days old visiting National Taiwan University Hospital Hsinchu branch were enrolled. The comparisons of G6PD enzyme activities among genotype groups were performed. RESULTS: G6PD enzyme activity was negatively correlated with age (R = -0.212, p = 0.01). For infants under 30 days of age, the G6PD enzyme activity levels were 1.4 ± 0.9 U/g Hb in hemizygotes (n = 76), 6.5 ± 2.0 U/g Hb in heterozygotes (n = 47), and 13.6 ± 3.7 U/g Hb in those without G6PD mutations (n = 70). Among infants more than 30 days old, G6PD enzyme activity levels were 0.9 ± 0.5 U/g Hb in hemizygotes (n = 46), 6.0 ± 2.7 U/g Hb in heterozygotes (n = 23), and 11.7 ± 3.4 U/g Hb in those without G6PD mutations (n = 148). G6PD levels differed significantly among the groups defined by genotypes. CONCLUSION: We determined G6PD enzyme activity levels in infants aged between 7 and 90 days in Taiwan. Completing the reference data and determining the cutoff values for different G6PD deficiency disease statuses will help pediatricians to make accurate diagnoses.

Nondiabetic kidney diseases in type 2 diabetic patients.

BACKGROUND: The aim of this study was to evaluate the clinical characteristics of nondiabetic nephropathy in type 2 diabetes mellitus patients and to find a clinical significance of renal biopsy and immunosuppressive treatment in such a patient. METHODS: Renal biopsy results, clinical parameters, and renal outcomes were analyzed in 75 diabetic patients who underwent kidney biopsy at Chungnam National University Hospital from January 1994 to December 2010. RESULTS: The three most common reasons for renal biopsy were nephrotic range proteinuria (44%), proteinuria without diabetic retinopathy (20%), and unexplained decline in renal function (20.0%). Ten patients (13.3%) had only diabetic nephropathy (Group I); 11 patients (14.7%) had diabetic nephropathy with superimposed nondiabetic nephropathy (Group II); and 54 patients (72%) had only nondiabetic nephropathy (Group III). Membranous nephropathy (23.1%), IgA nephropathy (21.5%), and acute tubulointerstitial nephritis (15.4%) were the three most common nondiabetic nephropathies. Group III had shorter duration of diabetes and lesser diabetic retinopathy than Groups I and II (P=0.008). Group II had the lowest baseline estimated glomerular filtration rate (P=0.002), with the greatest proportion of renal deterioration during follow-up (median 38.0 months, P<0.0001). The patients who were treated with intensive method showed better renal outcomes (odds ratio 4.931; P=0.01). Absence of diabetic retinopathy was associated with favorable renal outcome in intensive treatment group (odds ratio 0.114; P=0.032). CONCLUSION: Renal biopsy should be recommended for type 2 diabetic patients with atypical nephropathy because a considerable number of these patients may have nondiabetic nephropathies. And intensive treatment including corticosteroid or immunosuppressants could be recommended for type 2 diabetic patients with nondiabetic nephropathy, especially if the patients do not have diabetic retinopathy.