Paediatric thyroidectomy: When and why? A 25-year institutional experience.

OBJECTIVE: Thyroidectomy in paediatric patients is relatively uncommon. In this study, we reviewed our experience of thyroidectomy in children and identified risk factors associated with postoperative complications. METHODS: We performed a retrospective analysis of paediatric patients who had thyroidectomy in our institution between April 1995 and January 2021. Demographic data, preoperative cytological findings, indications of surgery, surgical complications and histological results were analysed. RESULTS: A total of 87 paediatric patients with 92 thyroidectomy were identified. The indications for surgery were Graves' disease refractory to medical treatments (40.2%), benign thyroid nodules or multinodular goitre (26.4%), thyroid carcinoma (23.0%) and multiple endocrine neoplasm type 2A syndrome (10.3%). Patients presented with thyroid nodules or cervical lymph nodes had a 43.9% risk of malignancy. 66 total thyroidectomy were done with median operation time of 134 min(102-170), while 26 hemi-thyroidectomy were performed (Right side 12/92, Left side 14/92) with median operation time of 65 min(49-102). The median postoperative hospital stay was 2 days(1-4). Intraoperative neck dissection (p = 0.003), drain insertion (p = 0.001) and hypocalcaemia requiring medical treatment (p = 0.004) were associated with longer hospital stay. The median follow-up was 11.3 years (3.0-16.8). 32% patients had immediate postoperative hypocalcaemia and 8% patients had permanent hypoparathyroidism. Transient vocal cord palsy was found in 3 patients(3%) and all resolved within 5-month time upon reassessment direct laryngoscopy. The use of intraoperative recurrent laryngeal nerve monitoring was associated with less vocal cord palsy (p = 0.022). The median disease-free survival was 13.7 years(7.4-17.7) for patients operated for well-differentiated thyroid carcinoma(WDTC). amongst the 9 patients who had prophylactic total thyroidectomy for MEN2A syndrome, 44% were found to have medullary thyroid microcarcinomas on pathology. CONCLUSIONS: Surgical management of paediatric thyroid disease can be complex. Postoperative hypocalcaemia and vocal cord palsy were usually transient after total thyroidectomy. The use of intraoperative recurrent laryngeal nerve monitoring had resulted in less vocal cord palsy. Long-term disease-free survival of patients with thyroid cancer had been achieved with multi-disciplinary management in our centre. LEVEL OF EVIDENCE: Retrospective Comparative Study; Level III.

Gut microbiota composition is associated with SARS-CoV-2 vaccine immunogenicity and adverse events.

OBJECTIVE: The gut microbiota plays a key role in modulating host immune response. We conducted a prospective, observational study to examine gut microbiota composition in association with immune responses and adverse events in adults who have received the inactivated vaccine (CoronaVac; Sinovac) or the mRNA vaccine (BNT162b2; BioNTech; Comirnaty). DESIGN: We performed shotgun metagenomic sequencing in stool samples of 138 COVID-19 vaccinees (37 CoronaVac and 101 BNT162b2 vaccinees) collected at baseline and 1 month after second dose of vaccination. Immune markers were measured by SARS-CoV-2 surrogate virus neutralisation test and spike receptor-binding domain IgG ELISA. RESULTS: We found a significantly lower immune response in recipients of CoronaVac than BNT162b2 vaccines (p<0.05). Bifidobacterium adolescentis was persistently higher in subjects with high neutralising antibodies to CoronaVac vaccine (p=0.023) and their baseline gut microbiome was enriched in pathways related to carbohydrate metabolism (linear discriminant analysis (LDA) scores >2 and p<0.05). Neutralising antibodies in BNT162b2 vaccinees showed a positive correlation with the total abundance of bacteria with flagella and fimbriae including Roseburia faecis (p=0.028). The abundance of Prevotella copri and two Megamonas species were enriched in individuals with fewer adverse events following either of the vaccines indicating that these bacteria may play an anti-inflammatory role in host immune response (LDA scores>3 and p<0.05). CONCLUSION: Our study has identified specific gut microbiota markers in association with improved immune response and reduced adverse events following COVID-19 vaccines. Microbiota-targeted interventions have the potential to complement effectiveness of COVID-19 vaccines.

Standard management protocol to improve the short-term outcome of biliary atresia.

AIM: This study compared the outcomes of patients with biliary atresia (BA) treated according to a standardised protocol with historical patients. METHODS: This is a single-centred retrospective study of BA patients treated from 1980 to 2016. A standardised treatment protocol was established since 2008 regarding peri-operative management. The outcomes being compared between the two groups (Groups I and II = before and after 2008, respectively) were jaundice clearance (JC), incidence of recurrent cholangitis, hospital admission and native liver survival (NLS). RESULTS: A total of 128 patients were included (Group I = 100, Group II = 28). The overall median follow-up period was 15.3 years (I vs. II = 20.6 years vs. 5.1 years, respectively). There was no significant difference in the JC at the sixth month between the two groups (I vs. II = 60.0 vs. 82.1%, respectively, P = 0.07). The incidence of recurrent cholangitis was similar between the two groups (I vs. II = 39 vs. 35.7%, respectively, P = 0.45), but the median hospital admission episode per patient was non-significantly higher in Group I (I vs. II = 4.2 vs. 2.7, respectively, P = 0.08). There was an improvement in the 1-year NLS rate in Group II (I vs. II = 69.0 vs. 85.7%, respectively, P = 0.05). CONCLUSIONS: The introduction of a standardised management protocol has improved the short-term outcome of BA patients, with a better 1-year NLS observed.

Recent trends in the prevalence of Helicobacter Pylori in symptomatic children: A 12-year retrospective study in a tertiary centre.

OBJECTIVE: Helicobacter pylori infection is common among Asians. However, evidence in the recent years has demonstrated a decrease in the prevalence of H. pylori infection among children and adults worldwide. Our aim was to update its prevalence in symptomatic children in our locality in the recent 12 years and compared to the results of our previous review published in 2005. METHODS: A retrospective review was carried out between 2005 and 2017. All children who presented with dyspepsia or gastrointestinal bleeding and underwent oesophagogastroduodenoscopy with antral biopsy taken were included. Patient demographics, endoscopic, or histological diagnosis and the H. pylori status were recorded. MAIN RESULTS: A total of 602 patients were included. There was a statistically significant decreasing trend of H. pylori infection rate between 2005 and 2017 (p = 0.003). The overall infection rate from this study was 12.8%, compared to 25.6% from our previous review. Overall failure of eradication with first-line antibiotic therapy has increased to 29.3% from 10% in our previous review. CONCLUSION: There was a decrease in the prevalence of H. pylori infection among symptomatic children for the recent 12 years, comparing to our previous data from 2005. We hypothesize that the reduction in prevalence of H. pylori infection among adults and the decrease in the practice of sharing chopsticks during meals have led to a decrease in transmission of the bacteria among family members in Hong Kong. However, the failure of eradication with first line treatment was higher, possibly due to the increase in antibiotics usage and resistance. LEVEL OF EVIDENCE: III.

Ultrafast laser-scanning time-stretch imaging at visible wavelengths.

Optical time-stretch imaging enables the continuous capture of non-repetitive events in real time at a line-scan rate of tens of MHz-a distinct advantage for the ultrafast dynamics monitoring and high-throughput screening that are widely needed in biological microscopy. However, its potential is limited by the technical challenge of achieving significant pulse stretching (that is, high temporal dispersion) and low optical loss, which are the critical factors influencing imaging quality, in the visible spectrum demanded in many of these applications. We present a new pulse-stretching technique, termed free-space angular-chirp-enhanced delay (FACED), with three distinguishing features absent in the prevailing dispersive-fiber-based implementations: (1) it generates substantial, reconfigurable temporal dispersion in free space (>1 ns nm-1) with low intrinsic loss (<6 dB) at visible wavelengths; (2) its wavelength-invariant pulse-stretching operation introduces a new paradigm in time-stretch imaging, which can now be implemented both with and without spectral encoding; and (3) pulse stretching in FACED inherently provides an ultrafast all-optical laser-beam scanning mechanism at a line-scan rate of tens of MHz. Using FACED, we demonstrate not only ultrafast laser-scanning time-stretch imaging with superior bright-field image quality compared with previous work but also, for the first time, MHz fluorescence and colorized time-stretch microscopy. Our results show that this technique could enable a wider scope of applications in high-speed and high-throughput biological microscopy that were once out of reach.

Pneumovesical Ureteric Reimplantation in Pediatric Patients: An Intermediate Term Result.

INTRODUCTION: Pneumovesical ureteric reimplantation has gained increasing popularity for the treatment of vesicoureteric reflux (VUR) and vesicoureteric junction obstruction (VUJO) in pediatric patients. In this study we reviewed our experience at an intermediate term basis. METHODS: A retrospective review of all patients with pneumovesical ureteric reimplantation performed in a tertiary referral center between 2005 and 2015 was carried out. Patients' demographics, operative measures, and postoperative outcomes were recorded. RESULTS: Thirty-one patients were identified during the study period. Twenty-three patients had VUR and 8 patients had VUJO. A total of 42 ureteric reimplantation procedures were carried out. The mean age at operation was 6.1 years old. The mean operative time was 221 minutes. On average the length of hospital stay was 7.4 days. Four patients required conversion to open approach. Four patients had low-grade residual VUR after the operation and all of them were treated conservatively. There was no major complication or mortality. CONCLUSION: Pneumovesical ureteric reimplantation is safe and effective for pediatric patients. Intermediate term result confirmed its reliability and low recurrence rate. It has good potential to become the preferred approach of choice in the future.

The cytotoxic effects of lipidic formulated gold porphyrin nanoparticles for the treatment of neuroblastoma.

OBJECTIVE: Nanotechnology has been identified as a promising platform in the improvement of the design and development of drug delivery systems. In the present study we investigated the potential of lipidic nanoparticles consisting of gold porphyrin for the treatment of neuroblastoma. MATERIALS AND METHODS: To characterize the size of the lipidic gold porphyrin nanoparticles, we used transmission electron microscopy (TEM). The in vitro cytotoxic effect on neuroblastoma activity was examined using XTT cell proliferation assay, then IC50 values were calculated. In vivo safety and toxicity were studied using intraperitoneal injection of gold porphyrin nanoparticles into normal animals. Finally, tumor size measurement and animal survival were studied to investigate the therapeutic effect of lipidic gold porphyrin nanoparticles on neuroblastoma growth. RESULTS: We found that incorporation of gold porphyrin into lipidic nanoparticles resulted in a 16-fold increase in size. Subsequent in vitro and in vivo cytotoxicity studies further showed that the lipidic gold porphyrin nanoparticles could decrease systemic toxicity, as well as inhibiting tumor growth following administration into the neuroblastoma bearing mice. CONCLUSION: The delivery of lipidic gold porphyrin nanoparticles by incorporation with lipidic formulation is feasible approach to treat neuroblastoma. We await further studies to evaluate tumor killing kinetics.