A case of Aicardi-Goutières syndrome caused by TREX1 gene mutation

Aicardi-Goutières syndrome (AGS) is a rare genetic disorder involving the central nervous system and autoimmune abnormalities, leading to severe intellectual and physical disability with poor prognosis. AGS has a phenotype similar to intrauterine viral infection, which often leads to delays in genetic counseling. In this study, we report a case with a prenatal diagnosis of AGS. The first fetal ultrasound detected bilateral lateral ventricle cystic structures, and fetal MRI was performed to identify other signs. The right parietal lobe signal showed cerebral white matter abnormalities, and fetal brain development level was lower than that of normal fetuses of the same gestational age. Whole-exome sequencing revealed that the fetus carried the TREX1:NM_033629.6:exon2:c.294dup:p. C99Mfs*3 variant, suggesting that the c.294dup mutation of the TREX1 gene was the pathogenic mutation site, and the final comprehensive diagnosis was AGS1. In this article, we also reviewed the previous literature for possible phenotypes in the fetus and found that microcephaly and intrauterine growth retardation may be the first and most important markers of the intrauterine phenotype of AGS.

Evaluation of the clinical value of carbon nanoparticles as lymph node tracer in differentiated thyroid carcinoma requiring reoperation

BACKGROUND

The incidence of parathyroid injury in patients with differentiated thyroid carcinoma (DTC) who underwent reoperation is significantly higher than that incurred from the initial surgery. The aim of this study was to investigate the clinical value of carbon nanoparticles (CN) as tracers for lymph nodes to guide cervical lymph node dissection and protect the parathyroid during reoperation for DTC.

METHODS

Our study recruited 116 patients with DTC who previously underwent thyroidectomy and later received remedial surgical treatment at the Department of Breast and Thyroid Surgery, Hunan Provincial People's Hospital, China, between February 2011 and February 2014. Those patients were randomly divided into the experimental group (the CN group) with 64 cases and the control group with 52 cases. Carbon nanoparticle suspension (CNS, 0.1-0.3 ml) was intraoperatively injected into the residual thyroid or enlarged lymph nodes in the CN group; in the control group, CNS was not applied intraoperatively. The differences in identification of the parathyroid glands, the number of lymph nodes resected intraoperatively, and the incidence of common complications after thyroidectomy in both groups were recorded and analyzed.

RESULTS

The accuracy of identification of the parathyroid in the CN group and control group was 92.2 % and 28.8 %, respectively, and the identification rate of three glands or more in both groups was 75 % and 36.5 %, respectively; those differences were statistically significant between the two groups (P < 0.05). There was also a significant difference between the two groups in the number of lymph nodes removed in the central and lateral cervical compartments (P < 0.05). There was no increase in common complications after the second surgery compared with the previous surgery; in addition, there was a decline in the incidence of transient hypoparathyroidism (HPT) (P < 0.05).

CONCLUSIONS

By tracing the thyroid and cervical regional lymph nodes with carbon nanoparticles, the parathyroid glands can be easily identified and protected to reduce the complications of transient hypoparathyroidism resulting from reoperation for residual or missed DTC. Carbon nanoparticle tracers also facilitate radical resection of lymph nodes at the central and lateral compartments of the neck.