Mild Neurological Manifestations Associated With Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Hospitalized Children During the Omicron Wave in Singapore: A Retrospective Cohort Review.

BACKGROUND: Neurological complications with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant have been reported in adults; however, there are little data in the pediatric population. We aimed to report on the prevalence and clinical characteristics of children with neurological symptoms during the SARS-CoV-2 omicron wave. METHODS: This was a single-center, retrospective cohort review of children (<18 years old) hospitalized for SARS-CoV-2 infection from December 2, 2021, to June 30, 2022. RESULTS: During the study period, 455 children (mean age 4.8 years, range 0.67 to 18, male 58.9%) were hospitalized with SARS-CoV-2 infection. A total of 108 (23.7%) children experienced neurological symptoms; most common were seizures (62.0%), headaches (32.4%) and giddiness (14.8%). Seizures included febrile seizures (64.1%), acute symptomatic seizures (17.9%), and breakthrough seizures in known epileptics (17.9%). Children with neurological manifestations were older (7.3 vs 4.0 years, P < 0.00001), more likely to have underlying epilepsy (9.3% vs 1.2%, P = 0.0002) or neurodevelopmental disorders (17.6% vs 1.7%, P < 0.00001), and presented earlier in their illness (2.1 vs 2.8 days, P < 0.00001), compared with those without neurological manifestations. Neurological symptoms fully resolved in all but one patient at discharge. There were no mortalities and no difference in duration of hospitalization (3.1 vs 3.7 days, P = 0.5) between the groups. CONCLUSIONS: One in four hospitalized children with SARS-CoV-2 infection when omicron variant was dominant experienced mild neurological symptoms. Overall risk factors for neurological symptoms associated with SARS-CoV-2 included older age, pre-existing febrile seizures/epilepsy and neurodevelopmental disorders.

Non-Tuberculous Mycobacterial Cervicofacial Lymphadenitis in Children-10-Year Experience in a Tertiary Pediatric Center.

BACKGROUND: Lymphadenitis is the most common manifestation of non-tuberculous mycobacteria (NTM) infection in children. We describe the epidemiology and clinical characteristics of NTM lymphadenitis, determine diagnostic yield from tissue sampling, and review management and outcomes. METHODS: This was a 10-year retrospective review of children aged 0-16 years diagnosed with NTM cervicofacial lymphadenitis who were seen in a pediatric infectious disease clinic in a tertiary public hospital. Data relating to patient demographics, clinical features, surgical and antimicrobial treatment, complications, and outcomes were retrieved from patients' electronic medical records and analyzed. RESULTS: There were 48 episodes of NTM cervicofacial lymphadenitis in 45 children (17 males and 28 females). Of these episodes, 43.7% manifested as a unilateral single node, mostly parotid (39.6%) and submandibular (29.2%). All patients underwent diagnostic fine-needle aspiration or surgery. Surgical excision more frequently yielded positive histological findings (P = .016). NTM was identified in 22/48 episodes (45.8%) via culture or molecular sequencing. Mycobacterium abscessus was most commonly found (47.8%). Thirty-eight children (79.2%) received antibiotics. Outcomes in 43 episodes revealed full resolution in 69.8%, while 25.6% had de novo disease and 4.6% experienced recurrence at the same site. Overlying skin changes and multiple or bilateral nodal diseases were significantly associated with de novo disease or recurrence (P = .034 and .084, respectively). Complications occurred in 11/70 (15.7%) procedures. Antibiotic-associated adverse effects occurred in 14/38 (36.8%) episodes. CONCLUSIONS: NTM lymphadenitis remains a challenging condition. More aggressive management with surgical excision and antibiotics is recommended for those with overlying skin changes and extensive nodal disease.

Anxiety in hospitalised families: lessons from the early phase of the COVID-19 pandemic.

Introduction: In the early phase of the coronavirus disease 2019 (COVID-19) pandemic, children with COVID-19 in Singapore required hospital isolation. We aimed to explore the psychological experiences of children and their caregivers isolated in a tertiary university hospital due to COVID-19. Methods: A prospective mixed-methods design was used to evaluate the psychological status of hospitalised family units with one or more children aged <18 years who had severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Patient medical records were reviewed for demographic and clinical information. Parents and children ≥7 years of age underwent a psychologist-administered telephone-based interview. Self-reported, age-appropriate instruments, Short Mood and Feelings Questionnaire, and Screen for Adult/Child Anxiety-Related Disorders, were used to assess anxiety and depression, respectively. Participants were also interviewed qualitatively. Results: Fifteen family units were hospitalised between March 2020 and May 2020. Of these, 13 (73%) family units were recruited. The median age of the children and median hospitalisation duration were 57 months and 21 days, respectively. Median number of COVID-19 polymerase chain reaction swabs performed for each child was eight. All children had asymptomatic to mild SARS-CoV-2 disease. The criteria indicative of anxiety disorder were met by 40% of adults and 80% of children, while the criteria indicative of separation anxiety were met by 60% of parents and 100% of children. One child met the criteria indicative of depression. Uncertainty, separation, prolonged hospitalisation and frequent swabs caused significant reported anxiety. Conclusions: Families, especially children, had heightened anxiety while in hospital isolation. Therefore, home-based recovery from COVID-19 and psychological support for children and their families, with focus on early recognition of anxiety disorders, are recommended. We support review of paediatric isolation policy as the pandemic evolves.

Strong Moiré Excitons in High-Angle Twisted Transition Metal Dichalcogenide Homobilayers with Robust Commensuration.

The burgeoning field of twistronics, which concerns how changing the relative twist angles between two materials creates new optoelectronic properties, offers a novel platform for studying twist-angle dependent excitonic physics. Herein, by surveying a range of hexagonal phase transition metal dichalcogenides (TMD) twisted homobilayers, we find that 21.8 ± 1.0°-twisted (7a×7a) and 27.8 ± 1.0°-twisted (13a×13a) bilayers account for nearly 20% of the total population of twisted bilayers in solution-phase restacked bilayers and can be found also in chemical vapor deposition (CVD) samples. Examining the optical properties associated with these twisted angles, we found that 21.8 ± 1.0° twisted MoS2 bilayers exhibit an intense moiré exciton peak in the photoluminescence (PL) spectra, originating from the refolded Brillouin zones. Our work suggests that commensurately twisted TMD homobilayers with short commensurate wavelengths can have interesting optoelectronic properties that are different from the small twist angle counterparts.

Low uptake of isoniazid window prophylaxis in patients exposed to a health-care worker with pulmonary tuberculosis in a paediatric ward.

AIM: A nurse on a paediatric multidisciplinary ward was diagnosed with smear-positive pulmonary tuberculosis. Children <2 years old, immunocompromised, or >40 h of contact (n = 173) were contact-traced. METHODS: Children received clinical review, chest X-ray, tuberculin skin test (TST; <5 years old) and/or an interferon-gamma release assay (Quantiferon TB-Gold, ≥5 years old). Infants <6 months old or children <5 years old screened <2 months from exposure were recommended isoniazid window prophylaxis (WP) until a repeat TST at 6 months old or 8-10 weeks after the last exposure to the index case, respectively. Empiric treatment for latent tuberculosis infection (LTBI) was individually considered for immunocompromised patients. RESULTS: Of 173 children (135 immunocompetent, 38 immunocompromised), two were uncontactable, seven refused screening and two immunocompromised children excluded. Eight of 126 immunocompetent children were diagnosed with LTBI (initial TST positive n = 7, TST conversion n = 1); seven started isoniazid. Thirty-two of 36 immunocompetent children were recommended WP; 15 accepted (one non-compliant after 1 month). Six of seven immunocompromised children accepted empiric LTBI treatment due to severe immunosuppression/initial indeterminate Quantiferon TB-Gold result. Of 15 immunocompromised children offered WP, only five accepted. CONCLUSIONS: There was high acceptance of screening but low uptake of isoniazid WP in high-risk children exposed to pulmonary tuberculosis. Perception of exposure risk and chemoprophylaxis should be explored further.

Unveiling Atomic-Scale Moiré Features and Atomic Reconstructions in High-Angle Commensurately Twisted Transition Metal Dichalcogenide Homobilayers.

Twisting the angle between van der Waals stacked 2D layers has recently sparked great interest as a new strategy to tune the physical properties of the materials. The twist angle and associated strain profiles govern the electrical and optical properties of the twisted 2D materials, but their detailed atomic structures remain elusive. Herein, using combined atomic-resolution electron microscopy and density functional theory (DFT) calculations, we identified five unique types of moiré features in commensurately twisted 7a×7a transition metal dichalcogenide (TMD) bilayers. These stacking variants are distinguishable only when the moiré wavelength is short. Periodic lattice strain is observed in various commensurately twisted TMD bilayers. Assisted by Zernike polynomial as a hierarchical active-learning framework, a hexagon-shaped strain soliton network has been atomically unveiled in nearly commensurate twisted TMD bilayers. Unlike stacking-polytype-dependent properties in untwisted structures, the stacking variants have the same electronic structures that suggest twisted bilayer systems are invariant against interlayer gliding.

Responding to COVID-19: how an academic infectious diseases division mobilized in Singapore.

BACKGROUND: On January 30, COVID-19 was declared a Public Health Emergency of International Concern-a week after Singapore's first imported case and 5 days before local transmission. The National University Hospital (NUH) is Singapore's third largest hospital with 1200 beds, heavy clinical workloads, and major roles in research and teaching. MAIN BODY: With memories of SARS still vivid, there was an urgent requirement for the NUH Division of Infectious Diseases to adapt-undergoing major reorganization to face rapidly changing priorities while ensuring usual essential services and standards. Leveraging on individual strengths, our division mobilized to meet the demands of COVID-19 while engaging in high-level coordination, strategy, and advocacy. We present our experience of the 60 days since the nation's first case. During this time, our hospital has managed 3030 suspect cases, including 1300 inpatients, 37 confirmed cases, and overseen 4384 samples tested for COVID-19. CONCLUSION: Complex hospital adaptations were supported by an unprecedented number of workflows and coordination channels essential to safe and effective operations. The actions we describe, aligned with international recommendations and emerging evidence-based best practices, may serve as a framework for other divisions and institutions facing the spread of COVID-19 globally.

Single Hepatitis B Booster Dose in High-risk Children with Suboptimal Surface Antigen Antibody Responses After 3-dose Primary Vaccine Series.

This was a descriptive study of 30 children born to HBsAG positive mothers between June 2009 and December 2013. All children had anti-HBs response ≤100 IU/L after 3 doses of hepatitis B vaccine primary series. A single booster dose led to hepatitis B surface antibody titers ≥100 IU/L in (85%) of children.

Pneumococcal Pneumonia Resembling Acute Myocardial Infarction in an Adolescent Male.

Myocarditis is commonly associated with viruses. However, we present a novel case of a teenager with pneumococcal pneumonia and bacteremia complicated by myocarditis and rhabdomyolysis, presenting with features of acute ST-elevation myocardial infarction and cardiogenic shock. Physicians should be aware that Streptococcus pneumoniae infection, like Group A Streptococcus, can mimic acute myocardial infarction in young males without cardiovascular risk factors.

Ethnic disparities in relationships of obesity indices with telomere length in Asians with type 2 diabetes.

BACKGROUND: Obesity and shorter telomeres increase the risk for diabetes complications and mortality. However, the relationship between obesity and telomere length in diverse Asian populations with type 2 diabetes (T2D) is not well understood. This study examined the association of baseline and changes in obesity indices with telomere length in multiethnic Asian populations with T2D. METHODS: Leukocyte telomere length (LTL) was measured by quantitative polymerase chain reaction in the SMART2D cohort (n = 1431 at baseline, n = 1039 after 3.2 years median follow-up). Associations between obesity indices and LTL were assessed by linear regression. RESULTS: Compared with Chinese, LTL was longer in Malays (P < 0.0001) and similar in Indians. Cross-sectionally, body mass index (BMI)-adjusted (residual) visceral fat area (VFA; ß = -0.004, P = 0.006), and waist-to-hip ratio (ß = -1.95, P = 0.030) were significantly associated with LTL in Chinese but not in Malays and Indians. Changes in BMI (r = -0.080; P = 0.053) and VFA (r = -0.126; P = 0.002) were inversely correlated with changes in LTL only in Chinese. Furthermore, in Chinese, 1-SD incremental changes in BMI (ß = -0.070; P = 0.040) and VFA (ß = -0.088, P = 0.028) were significantly associated with larger telomere attrition, independent of age, sex, diabetes condition, baseline LTL, obesity, and inflammation markers. CONCLUSIONS: Three-year changes in BMI and VFA were associated with telomere dynamics in Chinese but not in Malays and Indians with T2D. Reducing obesity may reduce the risk of diabetes complications associated with shorter LTL in the Chinese population.

Serologic Responses After Hepatitis B Vaccination in Preterm Infants Born to Hepatitis B Surface Antigen-Positive Mothers: Singapore Experience.

BACKGROUND: The Advisory Committee on Immunization Practices (ACIP) recommends a 4-dose vaccination schedule for preterm low birth weight infants (<2 kg) and a 3-dose vaccination schedule for preterm infants (≥2 kg) born to hepatitis B surface antigen (HBsAg)-positive mothers. However, data remain limited for these high-risk infants, and the optimal dosing schedule in Asia is not well established. AIM: The aim of this study was to evaluate the serologic vaccine responses in preterm infants born to HBsAg-positive mothers using current vaccination guidelines. METHODS: Preterm babies of gestation less than 37 completed weeks born to HBsAg-positive mothers were prospectively recruited during 6 years (June 2009 to December 2015) and retrospectively recruited via convenience sampling in 2 years (June 2013 to April 2015) in 2 tertiary pediatric centers. The preterm infants were given 4 or 3 vaccine doses as per ACIP 2005 guidelines. Vaccine response was defined as achieving hepatitis B surface antibody values of >10 IU/L [Abbott Architect (Abbott Laboratories, Chicago, IL)] at 9 months of chronologic age. RESULTS: A total of 24 preterm infants were recruited. Four had a birth weight <2 kg. Of 23 surviving infants, all were negative for HBsAg. One baby (4.5%) did not achieve adequate vaccine response. All 4 infants with birth weight <2 kg achieved seroprotective values. CONCLUSION: The current ACIP-recommended vaccination schedule results in adequate antibody responses in preterm infants of HBsAg-positive mothers.

Pulmonary Protothecosis in a Pediatric Liver Transplant Patient.

Immunocompromised patients are susceptible to infections from common and unusual microorganisms. Protothecosis is seldom suspected on clinical grounds, yet it is readily diagnosed once detected in the laboratory. We report the first pediatric liver transplant recipient with pulmonary protothecosis, detected during an episode of Pneumocystis jirovecii pneumonia, and we conducted a review of the available literature.