Purpose: Simple virilizing congenital adrenal hyperplasia (SV-CAH) due to 21-hydroxylase deficiency (21-OHD) is an autosomal recessive disease caused by pathogenic variants of the CYP21A2 gene. Children with SV-CAH often experience delayed diagnosis, presenting with pseudo-precocious puberty in males and genital virilization in females. Genotyping is essential for diagnosis, treatment, optimization, and phenotype prediction. This study describes the clinical and genetic characteristics of SV-CAH to guide treatment strategies. Methods: From November 2016 to March 2023, 79 children (accounting for 34.3% of 230 CAH cases in the overall children’s cohort) from 75 families were classified as SV-CAH due to 21-OHD at the Vietnam National Children's Hospital. Forty-three children underwent CYP21A2 mutation analysis using multiplex ligation-dependent probe amplification and complete gene sequencing to detect pathogenic variants. Results: Median age at diagnosis was 4.5 years (interquartile range, 1 day–22.3 years). There were 38.0% males and 62.0% females. The most common symptoms were penile enlargement in males (53.3%) and clitoromegaly (87.8%) in females; the height standard deviation (SD) at diagnosis was 1.90±1.79 SD (-2.02 to 5.43) according to the World Health Organization; and bone age advancement was 4.65±2.59 years. Genetic analysis identified 21 pathogenic variants and 22 genotypes in 43 children. The most common variant was p.I173N (47.7%); the most common genotype was p.I173N/p.I173N (16.3%). Conclusion Children with SV-CAH are often diagnosed late. To avoid that, early genetic analysis should be prioritized, especially for children diagnosed through newborn screening programs. Determining the genotype is crucial for optimizing treatment strategies, ensuring personalized management, and avoiding overtreatment.

We previously demonstrated that repeated exposure to extremely low frequency magnetic fields (ELF-MF) increases locomotor activity via stimulation of dopaminergic D1 receptor (J. Pharmacol. Sci., 2007;105:367-371). Since it has been demonstrated that activator protein-1 (AP-1) transcription factors, especially 35-kDa fos-related antigen (FRA), play a key role in the neuronal and behavioral adaptation in response to various stimuli, we examined whether repeated ELF-MF exposure induces FRA-immunoreactivity (FRA-IR) in the striatum and nucleus accumbens (striatal complex) of the mice. Repeated exposure to ELF-MF (0.3 or 2.4 mT, 1 h/day, for consecutive fourteen days) significantly induced hyperlocomotor activity and FRA-IR in the striatal complex in a field intensity-dependent manner. ELF-MF-induced FRA-IR lasted for at least 1 year, while locomotor activity returned near control level 3 months after the final exposure to ELF-MF. Pretreatment with SCH23390, a dopaminergic D1 receptor antagonist, but not with sulpiride, a dopaminergic D2 receptor antagonist, significantly attenuated hyperlocomotor activity and FRA-IR induced by ELF-MF. Our results suggest that repeated exposure to ELF-MF leads to prolonged locomotor stimulation and long-term expression of FRA in the striatal complex of the mice via stimulation of dopaminergic D1 receptor.
Animals ; Benzazepines ; Magnetic Fields ; Magnetics ; Magnets ; Mice ; Motor Activity ; Neurons ; Nucleus Accumbens ; Sulpiride ; Transcription Factor AP-1 ; Transcription Factors