Prevalence and clinical impact of mono- and co-infections with endemic coronaviruses 229E, OC43, NL63, and HKU-1 during the COVID-19 pandemic

Introduction

Endemic human coronaviruses (eHCoVs) are found worldwide and usually result in mild to moderate upper respiratory tract infections. They can lead to more severe illnesses such as croup, bronchiolitis, and pneumonia in vulnerable populations. During the coronavirus disease 2019 (COVID-19) pandemic, information on HCoV prevalence and incidence and clinical impact of co-infections of HCoV with SARS-CoV-2 was lacking.

Objectives

Thus, this study aimed to determine the prevalence and clinical significance of infections caused by eHCoVs during the COVID-19 pandemic in Bulgaria.

Methods

From January 2021 to December 2022, nasopharyngeal swabs of patients with acute upper or lower respiratory tract infections were tested for 17 respiratory viruses using multiplex real-time polymerase chain reaction assays. The clinical data and laboratory parameters of patients infected with respiratory viruses were analysed.

Results

Of the 1375 patients screened, 24 (1.7 %) were positive for HCoVs, and 197 (14.3 %) were positive for eight other seasonal respiratory viruses. Five (0.7 %) of 740 patients positive for SARS-CoV-2 were co-infected with eHCoVs. Co-infected patients had a mean C-reactive protein level of 198.5 ± 2.12 mg/mL and a mean oxygen saturation of 82 ± 2.8 mmHg, while those in patients co-infected with SARS-CoV-2 and other respiratory viruses were 61.8 mg/mL and 92.8 ± 4.6 mmHg, respectively (p < 0.05). Pneumonia was diagnosed in 63.3 % of patients with HCoV infection and 6 % of patients positive for other seasonal respiratory viruses (p < 0.05). Patients with SARS-CoV-2 mono-infection stayed in hospital for an average of 5.8 ± 3.7 days, whereas the average hospital stay of patients with eHCoV and SARS-CoV-2 co-infection was 9 ± 1.4 days (p < 0.05).

Conclusion

These findings indicate the low prevalence of eHCoVs and low co-infection rate between eHCoVs and SARS-CoV-2 during the COVID-19 pandemic in Bulgaria. Despite their low incidence, such mixed infections can cause severe signs that require oxygen therapy and longer hospital stays, underlining the need for targeted testing of severe COVID-19 cases to identify potential co-infections.

Hypomyelination with Atrophy of Basal Ganglia and Cerebellum (HABC) Due to UFM1 Mutation in Roma Patients - Severe Early Encephalopathy with Stridor and Severe Hearing and Visual Impairment. A Single Center Experience

BACKGROUND

Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a neurodegenerative disease with neurodevelopmental delay, motor, and speech regression, pronounced extrapyramidal syndrome, and sensory deficits due to TUBB4A mutation. In 2017, a severe variant was described in 16 Roma infants due to mutation in UFM1.

OBJECTIVE

The objective of this study is to expand the clinical manifestations of H-ABC due to UFM1 mutation and suggest clues for clinical diagnosis.

METHODOLOGY

Retrospective analysis of all 9 cases with H-ABC due to c.-273_-271delTCA mutation in UFM1 treated during 2013-2020 in a Neuropediatric Ward in Plovdiv, Bulgaria.

RESULTS

Presentation is no later than 2 months with inspiratory stridor, impaired sucking, swallowing, vision and hearing, and reduced active movements. By the age of 10 months, a monomorphic disease was observed: microcephaly (6/9), malnutrition (5/9), muscle hypertonia (9/9) and axial hypotonia (4/9), progressing to opisthotonus (6/9), dystonic posturing (5/9), nystagmoid ocular movements (6/9), epileptic seizures (4/9), non-epileptic spells (3/9). Dysphagia (7/9), inspiratory stridor (9/9), dyspnea (5/9), bradypnea (5/9), apnea (2/9) were major signs. Vision and hearing were never achieved or lost by 4-8 mo. Neurodevelopment was absent or minimal with subsequent regression after 2-5 mo. Brain imaging revealed cortical atrophy (7/9), atrophic ventricular dilatation (4/9), macrocisterna magna (5/9), reduced myelination (6/6), corpus callosum atrophy (3/6) and abnormal putamen and caput nuclei caudati. The age at death was between 8 and 18 mo.

CONCLUSION

Roma patients with severe encephalopathy in early infancy with stridor, opisthotonus, bradypnea, severe hearing and visual impairment should be tested for the Roma founder mutation of H-ABC in UFM1.

Association of NGF and Mitochondrial Respiration with Autism Spectrum Disorder

Background: NGF is a molecule with a pleiotropic role, affecting neuro-immune functions, energy homeostasis, and synaptic plasticity. The mechanisms of NGF-induced neuronal differentiation are well established, but its effect on mitochondria in autism spectrum disorder (ASD) is still unclear. We hypothesize that NGF-induced neuronal development requires large amounts of energy, and mitochondria in ASD are overloaded to meet the new functional requirements. Method: The study includes primary diagnosed ASD children. Peripheral blood mononuclear cells (PBMCs) and plasma were obtained from both patients and typically developing children (TDC). PBMCs were analyzed with Seahorse XFp, and plasma NGF protein levels were measured. Results: We detected nearly 50% higher NGF levels and approximately 40% elevation in spare respiratory capacity in ASD compared to TDC. These findings are consistent with the observed difference in maximal respiration, which was also significantly higher in the patient group. Both mitochondrial respiration and NGF plasma levels exhibit a strong potential to discriminate children with ASD from TDC. Conclusions: This study is the first to link elevated NGF with mitochondrial respiration and altered energy homeostasis in ASD. High NGF correlates with basic bioenergetic signatures that may be used as a screening tool to improve early diagnosis and clinical follow-up in ASD.

Clinical significance and role of coinfections with respiratory pathogens among individuals with confirmed severe acute respiratory syndrome coronavirus-2 infection

Introduction

This study aimed to determine the prevalence, viral profile, and clinical features of coinfections with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and other respiratory viruses.

Methods

Nasopharyngeal samples and clinical data of 221 hospitalized patients and 21 outpatients were collected and analyzed. Real-time reverse transcription-polymerase chain reaction was used to detect SARS-CoV-2, influenza virus, respiratory syncytial virus (RSV), human metapneumovirus (HMPV), parainfluenza virus (PIV) 1,2,3, rhinovirus (RV), adenovirus (AdV), bocaviruses (BoV), and seasonal coronaviruses (OC43, 229E, NL63, and HKU1). Viral load was determined by capillary electrophoresis.

Results

From November 2020 to mid-March 2022, 242 SARS-CoV-2 positive patients were tested for seasonal respiratory viruses, and 24 (9.9%) cases of coinfections were detected. The distribution of viruses involved in cases of coinfections were as follows: HMPV (n = 6; 25%), RSV (n = 4;16.7%), AdV (n = 4; 16.7%), BoV (n = 4; 16.7%), PIV3 (n = 2; 8.3%), influenza A (H3N2; n = 2; 8.3%), RV (n = 1; 4.62%), and RV+BoV (n = 1; 4.62%). The proportion of detected coinfections with SARS-CoV-2 was highest in children aged 0-5 years (59%), followed by those >65 years (33%). In specimens with detected coinfection, the viral load of influenza was higher than that of SARS-CoV-2, and the mean viral load of SARS-CoV-2 was higher than that of the other respiratory viruses. C-reactive protein (CRP) and lymphocytes count in co-infected patients >65 years of age were on average higher than in children <16 years of age (mean CRP of 161.8 ± 133.1 mg/L; 19.7 ± 3.09% vs. mean 6.9 ± 8.9 mg/L, 0.9 ± 3.1%; p < 0.01). Patients >65 years of age co-infected with SARS-CoV-2 and other respiratory viruses had longer hospital stays than those <16 years of age (mean 9 ± 3.96 days vs. 5.44 ± 1.89 days; p = 0.025). The combination of AdV and SARS-CoV-2 is fatal for patients aged >65 years.

Conclusion

In patients aged >65 years, coinfection with SARS CoV-2 and other respiratory viruses, together with concomitant diseases, causes worsening of the clinical picture and complications, and can be fatal. Screening of patients with SARS CoV-2 for other respiratory viruses is needed to select appropriate treatments and prevent a fatal outcome of the disease.

Cellular Bioenergetic and Metabolic Changes in Patients with Autism Spectrum Disorder

BACKGROUND

Although Autism Spectrum Disorder (ASD) is considered a heterogeneous neurological disease in childhood, a growing body of evidence associates it with mitochondrial dysfunction explaining the observed comorbidities.

INTRODUCTION

The aim of this study is to identify variations in cellular bioenergetics and metabolism dependent on mitochondrial function in ASD patients and healthy controls using Peripheral Blood Mononuclear Cells (PBMCs). We hypothesized that PBMCs may reveal the cellular pathology and provide evidence of bioenergetic and metabolic changes accompanying the disease.

METHODS

PBMC from children with ASD and a control group of the same age and gender were isolated. All patients underwent an in-depth clinical evaluation. A well-characterized cohort of Bulgarian children is selected. Bioenergetic and metabolic studies of isolated PBMCs are performed with a Seahorse XFp analyzer.

RESULTS

Our data show that PBMCs from patients with ASD have increased respiratory reserve capacity (by 27.5%), increased maximal respiration (by 67%) and altered adaptive response to oxidative stress induced by DMNQ. In addition, we demonstrate а strong dependence on fatty acids and impaired ability to reprogram cell metabolism. The listed characteristics are not observed in the control group. These results can contribute to a better understanding of the underlying causes of ASD, which is crucial for selecting a successful treatment.

CONCLUSION

The current study, for the first time, provides a functional analysis of cell bioenergetics and metabolic changes in a group of Bulgarian patients with ASD. It reveals physiological abnormalities that do not allow mitochondria to adapt and meet the increased energetic requirements of the cell. The link between mitochondria and ASD is not yet fully understood, but this may lead to the discovery of new approaches for nutrition and therapy.

First case of Roma ethnic origin with Andermann syndrome: A novel frameshift mutation in exon 20 of SLC12A6 gene

Andermann syndrome (AS) is caused by mutation of SLC12A6 gene. It comprises severe progressive sensory and motor neuropathy with early onset, varying degree of agenesis of corpus callosum (ACC) and mental retardation. AS occurs occasionally among population outside the northeastern Quebec-Saguenay-Lac- St-Jean and Charlevoix regions, inhabited by French Canadians. None of the described patients were of Roma ethnic origin. We present an 8-month-old infant of Roma ethnic origin with AS, caused by a novel frame shift mutation c.2604delT,p.(Asp868GlufsTer11) in exon 20 of SLC12A6 gene. Our case presented with several atypical findings: clinical presentation resembling "spinal muscular atrophy plus" syndrome; tongue fasciculations, which are not reported in the literature; early contractures of the wrists; normal motor action potentials and preserved sensory action potentials. Our patient is the first of Roma origin from nonconsanguineous parents, which suggests that this mutation might be widespread in the Roma population, although screening for this mutation in 140 alleles from Roma individuals originating from the same geographic region did not reveal further carriers, implying the mutation is rare. We recommend that Roma patients presenting with the clinical phenotype of AS should be tested for this mutation primarily.

Developmental performance of 5-year-old Bulgarian children-An example of translational neuroscience in practice

RATIONALE, AIMS, AND OBJECTIVES

Developmental testing is essential for early recognition of the various developmental impairments. The tools used should be composed of items that are age specific, adapted, and standardized for the population they are applied to. The achievements of neurosciences, medicine, psychology, pedagogy, etc. are applied in the elaboration of a comprehensive examination tool that should screen all major areas of development. The key age of 5 years permits identification of almost all major developmental disabilities leaving time for therapeutic intervention before school entrance. The aim of the research is to evaluate the developmental performance of 5-year-old Bulgarian children using the approach of translation neuroscience.

METHOD

A comprehensive test program was developed composed of 89 items grouped in the following domains: fine and gross motor development, coordination and balance, central motor neuron disturbances, language development and articulation, perception, attention and behavior, visual acuity, and strabismus. The overall sample comprises 434 children of mean age 63.5 months (SD-3.7). Male to female ratio is 1:1.02. From this group, 390 children are between 60 and 71 months of age. The children are examined in 51 kindergartens in 21 villages and 18 cities randomly chosen in southern Bulgaria. Eight children were excluded from the final analysis because they fulfilled less than 50% of the test items (7 children did not cooperate and 1 child was with autistic spectrum disorder).

RESULTS

The items with abnormal response in less than 5% of the children are 43. The items with abnormal response in 6% to 35% of the children are 37. The items with high abnormal response (more than 35%) rate are only 9.

CONCLUSIONS

The test is an example of a translational approach in neuroscience. On one hand, it is based on the results of several sciences studying growth and development from different perspective. On the other hand, the results from the present research may be implemented in other fields of child development-education, psychology, speech and language therapy, and intervention programs.

Pontocerebellar hypoplasia type 1 for the neuropediatrician: Genotype-phenotype correlations and diagnostic guidelines based on new cases and overview of the literature

Pontocerebellar hypoplasia type 1 (PCH1) is a major cause of non-5q spinal muscular atrophy (SMA). We screened 128 SMN1-negative SMA patients from Bulgaria for a frequent mutation -p.G31A in EXOSC3, and performed a literature review of all genetically verified PCH1 cases. Homozygous p.G31A/EXOSC3 mutation was identified in 14 Roma patients, representing three fourths of all our SMN1-negative Roma SMA cases. The phenotype of the p.G31A/EXOSC3 homozygotes was compared to the clinical presentation of all reported to date genetically verified PCH1 cases. Signs of antenatal onset of disease present at birth were common in all PCH1 sub-types except in the homozygous p.D132A/EXOSC3 patients. The PCH1sub-types with early death (between ages 1 day and 17 months), seen in patients with p.G31A/EXOSC3 or SLC25A46 mutations have a SMA type 1-like clinical presentation but with global developmental delay, visual and hearing impairment, with or without microcephaly, nystagmus and optic atrophy. Mutations with milder presentation (homozygous p.D132A/EXOSC3 or VRK1) may display additionally signs of upper motor neuron impairment, dystonia or ataxia and die at age between 5 and 18 years. Other EXOSC3 mutations and EXOSC8 cases are intermediate - SMA type 1-like presentation, spasticity (mostly in EXOSC8) and death between 3 months and 5 years. There is no correlation between neurological onset and duration of life. We add marble-like skin and congenital laryngeal stridor as features of PCH1. We show that imaging signs of cerebellar and pontine hypoplasia may be missing early in infancy. EMG signs of anterior horn neuronopathy may be missing in PCH1 patients with SLC25A46 mutations. Thus, there is considerable phenotypic variability in PCH1, with some cases being more SMA-like, than PCH-like. Detailed clinical evaluation and ethnicity background may guide genetic testing and subsequent genetic counseling.