SLC22A5 Mutations in a Patient With Systemic Primary Carnitine Deficiency and Cleft Palate-Successful Perioperative Management:

Exploring a novel model for newborn genetic screening in Ningxia, northern China: A retrospective observational study

The accuracy and precision of quantitative aspects of conventional newborn screening (NBS) are limited due to the complexity of clinical manifestations and the constraints of conventional screening methods. Gene sequencing is commonly employed as an adjunct diagnostic technique to assist in diagnosis. The combined utilization of traditional NBS and newborn genetic screening can effectively reduce false-negative and false-positive rates, thereby enhancing the accuracy and precision of screening, while minimizing the health impact caused by genetic diseases in infants. This study aim to explore the feasibility and effectiveness of newborn genetic screening in Ningxia. For the first time in Ningxia, a genetic sequencing panel based on multiplex PCR technology and next-generation sequencing (NGS) combined with traditional mass spectrometry (MS/MS) was used for initial NBS. This involved the analysis of 134 disease-causing genes covering 74 common inborn disorders. A total of 1837 newborns were screened from January 2020 to December 2021 in the Ningxia region, and 7 positive cases were detected by gene panel among the 1837 newborns including 1 PAH disorder, 1 DUOX2 disorder, 1 G6PD disorder and 4 MT-RNR1 disorders. However, no 1 has yet been detected using traditional NBS. The top ten high-frequency mutant genes detected in the panel test were arranged from high to low as follows: PAH, DUOX2, SLC26A4, GJB2, ATP7B, MMACHC, SLC22A5, ACADS, DUOXA2 and SLC25A13. Population-specific newborn genetic screening can facilitate the progress of genetic defect prevention and treatment.

Newborn screening for primary carnitine deficiency in Quanzhou, China

BACKGROUND AND AIMS

Primary carnitine deficiency (PCD) is an autosomal recessive disease caused by functional defects in the carnitine transporter OCTN2 due to mutations in SLC22A5. Here, we aimed to understand the incidence, clinical, biochemical, and molecular features of PCD in Quanzhou, China.

MATERIALS AND METHODS

Newborn screening (NBS) was performed through tandem mass spectrometry (MS/MS) to detect genetic metabolic diseases. Next-generation sequencing was used to detect SLC22A5 mutations in patients with suspected PCD.

RESULTS

From 364,545 newborns screened, 36 were diagnosed with PCD, in addition to five mothers. The incidence of PCD in children in the Quanzhou area was 1:10126. Eighteen SLC22A5 variants were found, with five novel ones. The most prevalent variant in neonatal and maternal patients was c.760C > T (p.R254*). Twenty-five neonatal patients received L-carnitine supplementation; however, one patient discontinued treatment and sudden death occurred. One sibling presented repeated fatigue, hypoglycemia, and coma, but the symptoms disappeared after treatment. Two mothers with PCD claimed to feel weak and easily fatigued.

CONCLUSION

The incidence of PCD is relatively high in the Quanzhou area. Five novel variants were found, broadening the mutation spectrum of SLC22A5. NBS is effective in identifying PCD, and sudden death may be prevented with timely treatment.

Titanium Three-Dimensional Printed Cranioplasty for Fronto-Nasal Bone Defect

OBJECTIVE

To analyze the characteristics and outcome of patients who underwent the insertion of a 3-dimensional (3D) printed titanium (Materialise) cranioplasty.

METHODS

Surgical and clinical data of patients who underwent 3D printed titanium cranioplasty insertion at our institution were retrospectively reviewed.

RESULTS

A retrospective search identified 19 cases of titanium cranioplasty insertion between 2012 and 2018. 12 patients were male (63.2%) and mean age at cranioplasty was 47.4 ± 11.3 years. 9 patients had the cranioplasty inserted during the very same procedure of the craniectomy and 10 at a separate surgical stage from the craniectomy. Median delay from the craniectomy until the prosthesis insertion was 0.6 years, interquartile range (IQR) [0.4, 0.9]. Side of cranioplasty insertion was right in 6 cases and in the midline frontal in 9. Median surface of the implant was 68.1 cm, IQR [53, 125.4]. Median follow-up since the cranioplasty insertion was 1.2 year, IQR [0.4, 2.1]. At data collection, 1 patient was lost to follow-up, 1 had its cranioplasty taken out but, none was reported dead. 6 patients (31.6%) experienced early post-operative complications following the cranioplasty insertion. One patient had its cranioplasty removed 2.5 years after the insertion for tumoral recurrence (hemagiopericytoma) and skin necrosis leading to the plate exposure.

CONCLUSION

3D printed titanium cranioplasty are useful for complex craniofacial reconstruction regardless the etiology of the skull defect. This device is not associated with a higher rate of complication.