Challenges in the era of COVID-19: Starting from the clinical examination

Introduction: Physical examination remains the cornerstone of medical practice. However, its importance has been underestimated during COVID-19 pandemic because of concerns related to exposure risk and use of personal protective equipment. Solitary median maxillary central incisor (SMMCI) may be an isolated clinical trait or associated with other anomalies and endocrine pathologies including hypopituitarism, hypothyroidism, isolated growth hormone (GH) deficiency, precocious or delayed puberty, short stature without GH abnormalities. Aim(s): The aim of this case presentation is to underline the significance of clinical examination, as in SMMCI, an important clinical finding that may lead to an early diagnosis of hidden endocrine abnormalities. Material(s) and Method(s): A 78/12-year-old girl was hospitalised because of an episode of acute headache with walking instability. Her past medical history was uneventful except for premature adrenarche since the age of 56/12 years. A paediatric endocrinologist had estimated her 2 years before, at the onset of the COVID-19 pandemic and ordered hormone assays and a Synachten test. Because of her past medical history and the positive family history for type 2 diabetes, she underwent a detailed hormone laboratory evaluation including oral glucose tolerance test (OGTT) and LHRH test. Furthermore, because of the borderline response in 17-hydroxyprogesterone following ACTH stimulation, CYP21A2 gene analysis was performed. Result(s): Her clinical examination revealed excessive body mass index (18.9 kg/m2, 90th percentile) and B I and PH II-III Tanner stage with axillary hair and odor. OGTT revealed insulin resistance (HOMA-IR 3.38). Based on the increased LH response in GnRH test (LH at 30 min 3.8 IU/L) in association to the increased ovarian volume (3.25 and 5.3 ml with 6 and 9 follicles respectively), she was diagnosed with central precocious puberty (CPP). At the time of final clinical and laboratory overview by the Chief of the Unit, the girl was asked to put off her mask, unraveling a SMMCI, a finding not having been identified and correctly evaluated until then. Consequently, a pituitary gland magnetic resonance imaging (MRI) was mandatory, revealing ectopic posterior pituitary at the pituitary stalk with hypoplasia of anterior pituitary, possibly implicated in the CPP aetiology. The patient was prescribed triptorelin and is on regular endocrine follow-up. Conclusion(s): SMMCI, so easily diagnosed, may be the cardinal clinical feature guiding further physical, endocrine laboratory and imaging investigation and leading to early diagnosis of endocrine pathology. Clinical examination remains the key of paediatric endocrine evaluation, overcoming any potential risk in the era of COVID-19.

Identification of Complement-Related Missense Variants in Pediatric Patients with Acute and Post COVID-19 Syndromes

Background: Complement dysregulation has been documented in the molecular pathophysiology of COVID-19 and recently implicated in the relevant pediatric patient inflammatory responses. Aims: Based on our previous data in adults, we hypothesized that signatures of complement genetic variants would also be detectable in pediatric patients exhibiting COVID-19 signs and symptoms. Methods: We prospectively studied consecutive pediatric patients from our COVID-19 Units (November 2020-March 2021). COVID-19 was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). Patient data were recorded by treating physicians that followed patients up to discharge. DNA was obtained from peripheral blood samples. Probes were designed using the Design studio (Illumina). Amplicons cover exons of complement-associated genes (C3, C5, CFB, CFD, CFH, CFHR1, CFI, CD46, CD55, MBL2, MASP1, MASP2, COLEC11, FCN1, FCN3 as well as ADAMTS13 and ΤHBD) spanning 15 bases into introns. We used 10ng of initial DNA material. Libraries were quantified using Qubit and sequenced on a MiniSeq System in a 2x150 bp run. Analysis was performed using the TruSeq Amplicon application (BaseSpace). Alignment was based on the banded Smith-Waterman algorithm in the targeted regions (specified in a manifest file). We performed variant calling with the Illumina-developed Somatic Variant Caller in germline mode and variant allele frequency higher than 20%. Both Ensembl and Refseq were used for annotation of the output files. A preliminary analysis (A) for the identification of variants of clinical significance was based on annotated ClinVar data, while a further and more selective analysis (B) was performed to identify missense complement coding variants that may biochemically contribute to the deregulation of innate responses during infection. This analysis was mainly based on the dbSNP and UniProt databases and available literature. Results: We studied 80 children and adolescents, 8 of whom developed inflammatory syndromes (MIS-C group). Among them, 41 were hospitalized and eventually all survived. 1. In our preliminary analysis, patients exhibited heterogeneous variant profiles including pathogenic, benign, likely benign, and variants of unknown significance (median number of variants: 97, range: 61-103). We found a variant of ADAMTS13 (rs2301612, missense) in 39 patients. We also detected two missense risk factor variants, previously detected in complement-related diseases: rs2230199 in C3 (33 patients);and rs800292 in CFH (36 patients). Among them, 40 patients had a combination of these characterized variants. This combination was significantly associated with the presence of dyspnea (p=0.031) and cough (p=0.042). Furthermore, 27 patients had a pathogenic variant in MBL2 (rs1800450), and 7 a pathogenic deletion in FCN3 that have been previously associated with inflammatory syndromes. 2. The results of our further analysis are summarized in Figure. We identified common variants, some well represented by relatively high frequencies (>70%) (rs11098044 in CFI, rs1061170 in CFH and rs12711521 in MASP2) and others less abundant, but varying considerably between the hospitalized group, the non-admitted group and the MIS-C individuals (rs2230199 in C3, rs1065489 in CFH, rs12614 and rs641153 in CFB, rs1800450 in MBL2, rs2273346 and rs72550870 in MASP2, rs72549154 in MASP3 and rs7567833 in COLEC11, all highlighted in Figure in red).). Structurally, the majority of these common variants of interest encode charge reversal mutations. These may influence protein-protein interactions in complex formations that are important for complement activation and/or regulation. Conclusion: In pediatric COVID-19 we have detected a novel set of complement missense coding variants some of which have been implicated earlier in inflammatory syndromes and endothelial stress responses. Certain combinations of mutations of alternative and/or lectin pathway components may increase the threshold dynamics of complement consumption and therefore alter COVID-19 phenotypes. [Formula prese ted] Disclosures: Gavriilaki: Alexion, Omeros, Sanofi Corporation: Consultancy;Gilead Corporation: Honoraria;Pfizer Corporation: Research Funding. Anagnostopoulos: Abbvie: Other: clinical trials;Sanofi: Other: clinical trials;Ocopeptides: Other: clinical trials;GSK: Other: clinical trials;Incyte: Other: clinical trials;Takeda: Other: clinical trials;Amgen: Other: clinical trials;Janssen: Other: clinical trials;novartis: Other: clinical trials;Celgene: Other: clinical trials;Roche: Other: clinical trials;Astellas: Other: clinical trials.