Precocious puberty in patients with Pompe disease.

Introduction: The life expectancy of Pompe disease patients has increased due to improved neonatal screening and enzyme replacement therapy. Nevertheless, the potential effect of frequent medical device exposure on pubertal development in these patients is not well understood, so further investigation is warranted. Methods: In this cross-sectional study, we assessed the growth and puberty of nine Pompe disease patients. In addition, to determine the effects of frequent plastic medical device exposure in these patients, we measured urinary phthalate metabolites before and one day after enzyme replacement therapy. Results: Five out of nine patients (55%) with Pompe disease on enzyme replacement therapy had precocious puberty. Patients with precocious puberty had significantly shorter predicted adult heights compared to those with normal puberty (p = 0.014). The levels of mono-2-ethylhexyl phthalate (MEHP) and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP) increased after enzyme replacement therapy, but the average levels of phthalate metabolites did not significantly differ between patients with normal and precocious puberty. Conclusion: Pompe disease patients on enzyme replacement therapy tend to have precocious puberty, which may reduce their adult height. There are no significant differences in urinary phthalate metabolites between normal and precocious puberty patients. Regular follow-up of growth and puberty in Pompe disease patients is important to improve their health outcomes.

Curated incidence of lysosomal storage diseases from the Taiwan Biobank.

Lysosomal storage diseases (LSDs) are a group of metabolic disorders resulting from a deficiency in one of the lysosomal hydrolases. Most LSDs are inherited in an autosomal or X-linked recessive manner. As LSDs are rare, their true incidence in Taiwan remains unknown. In this study, we used high-coverage whole-genome sequencing data from 1,495 Taiwanese individuals obtained from the Taiwan Biobank. We found 3826 variants in 71 genes responsible for autosomal recessive LSDs. We first excluded benign variants by allele frequency and other criteria. As a result, 270 variants were considered disease-causing. We curated these variants using published guidelines from the American College of Medical Genetics and Genomics (ACMG). Our results revealed a combined incidence rate of 13 per 100,000 (conservative estimation by pathologic and likely pathogenic variants; 95% CI 6.92-22.23) to 94 per 100,000 (extended estimation by the inclusion of variants of unknown significance; 95% CI 75.96-115.03) among 71 autosomal recessive disease-associated genes. The conservative estimations were similar to those in published clinical data. No disease-causing mutations were found for 18 other diseases; thus, these diseases are likely extremely rare in Taiwan. The study results are important for designing screening and treatment methods for LSDs in Taiwan and demonstrate the importance of mutation curation to avoid overestimating disease incidences from genomic data.

Adult height of children with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

BACKGROUND/PURPOSES: Congenital adrenal hyperplasia attributable to 21-hydroxylase deficiency (21-OHD) is a disorder of adrenal steroidogenesis. Achievement of optimal growth by such patients is challenging. We evaluated the adult height of Taiwanese children with 21-OHD and the effect of a gonadotropin-releasing hormone analogue (GnRHa) in patients with central precocious puberty (CPP) complicating 21-OHD. METHODS: Among 116 patients with 21-OHD in Taiwan, 90 who had attained adult height were subjected to an analysis of height outcomes. Nine with progressive CPP were treated with GnRHa and the effects of this therapy on adult height were further analyzed. RESULTS: In the pre-screening era, the percentage of boys with 21-OHD was lower than expected. Although neonatal screening can prevent mortality caused by adrenal crisis, some cases may be missed. The pooled mean adult height of the 78 patients treated with conventional therapy were -1.1 SD and -0.5 SD adjusting for the genetic potential. The disease features affecting height outcomes are the genetic height potential and in boys the simple virilizing type. Nine patients with CPP were treated with GnRHa in addition to conventional therapy; the mean adult height increased from the predicted -4.1 SD to -1.0 SD after 6.0 ± 2.5 years of treatment. CONCLUSION: Patients with 21-OHD had poorer mean adult height. A high caregiver's index of suspicion is required for the early diagnosis of patients with 21-OHD missed on neonatal screening. Adjuvant therapy with GnRHa can improve the adult height of patients with CPP complicating 21-OHD.

A missense variant in the nuclear localization signal of DKC1 causes Hoyeraal-Hreidarsson syndrome.

Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is caused by mutations in genes involved in telomere maintenance. Here, we identified male siblings from a family with HHS carrying a hemizygous mutation (c.1345C > G, p.R449G), located in the C-terminal nuclear localization signal (NLS) of the DKC1 gene. These patients exhibit progressive cerebellar hypoplasia, recurrent infections, pancytopenia due to bone marrow failure, and short leukocyte telomere lengths. Single-cell RNA sequencing analysis suggested defects in the NLRP3 inflammasome in monocytes and the activation and maturation of NK cells and B cells. In experiments using induced pluripotent stem cells (iPSCs) from patients, DKC1_R449G iPSCs had short telomere lengths due to reduced levels of human telomerase RNA (hTR) and increased cytosolic proportions of DKC1. Treatment with dihydroquinolizinone RG7834 and 3'deoxyanosine cordycepin rescued telomere length in patient-derived iPSCs. Together, our findings not only provide new insights into immunodeficiency in DC patients but also provide treatment options for telomerase insufficiency disorders.

Short stature leads to a diagnosis of Jansen-de Vries syndrome in two unrelated Taiwanese girls: A case report and literature review.

Short stature and intellectual disability are two of the major components of many dysmorphic syndromes. Jansen-de Vries syndrome (JDVS) is a rare syndromic disorder that was discovered recently using next-generation sequencing. It is characterized by hypotonia, developmental delay, a dysmorphic face, short stature, and high pain threshold and is caused by the variants of the protein phosphatase magnesium-dependent 1D (PPM1D) gene. Here, we report the first two cases of PPM1D mutations in Taiwan; both had de novo variants in exon 6. Both presented with short stature, developmental delay, and dysmorphic faces. In addition to the characteristics listed above, syndactyly was noted in one. Genetic studies should be considered when approaching a patient with growth retardation, intellectual disability, and other major or minor dysmorphisms.