Letter to the editor: Post COVID-19 joint pain: Preliminary report of the relationship with antinuclear antibodies and inflammation

Phalangeal microgeodic syndrome: a paediatric case series

We present the clinical and radiological characteristics of phalangeal microgeodic syndrome in a cluster of five children during the second peak of COVID-19 pandemic in the UK. Each child presented with phalangeal swelling and erythema, prompting a comprehensive multi-disciplinary team review to analyse the clinical presentation, blood test results and imaging. The cohort's average age was 14.1 years, ranging from 10.4 to 16.6 years, with two girls and three boys. Four children experienced phalangeal involvement in the hands, whilst one was affected solely in the feet. A rheumatological work-up was performed for all. Hand X-rays performed on three children revealed distinct radiographic features like microgeodes, subperiosteal bone resorption and rarefaction in two cases. However, further MRI showed extensive changes closely correlated with the clinical signs of cutaneous vasculopathic rashes. The MRI abnormalities were notable, encompassing marrow oedema primarily affecting metaphyses and epiphyses, displaying broad transition zones. Soft tissue swelling and cortical erosions were also observed. These MRI features proved more pathognomonic in the acute clinical context. The study concluded that phalangeal microgeodic syndrome, characterised by digital swelling and erythema, might not be adequately assessed by plain X-rays. The more comprehensive MRI features, including marrow oedema and soft tissue abnormalities, appeared to be more indicative in diagnosing the condition. Considering the rarity of this syndrome and its temporal association with the COVID-19 pandemic, the study hypothesised that COVID-related thrombophilia and immune-mediated vasculopathy might act as crucial triggers for the active bony manifestations seen in this syndrome. KEY POINTS: • PMS is a rare, predominantly paediatric condition, of unknown aetiology which affects the digits. • Laboratory investigations are generally negative; however, in the appropriate clinical context, the X-ray findings of microgeodes and pattern of bone marrow oedema seen on MRI are pathognomonic. • Considering the rarity of PMS and temporal association with the COVID-19 pandemic, COVID vasculopathy may represent a previously unrecognised aetiology for PMS.

COVID-19 and Long COVID: Disruption of the Neurovascular Unit, Blood-Brain Barrier, and Tight Junctions

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), could affect brain structure and function. SARS-CoV-2 can enter the brain through different routes, including the olfactory, trigeminal, and vagus nerves, and through blood and immunocytes. SARS-CoV-2 may also enter the brain from the peripheral blood through a disrupted blood-brain barrier (BBB). The neurovascular unit in the brain, composed of neurons, astrocytes, endothelial cells, and pericytes, protects brain parenchyma by regulating the entry of substances from the blood. The endothelial cells, pericytes, and astrocytes highly express angiotensin converting enzyme 2 (ACE2), indicating that the BBB can be disturbed by SARS-CoV-2 and lead to derangements of tight junction and adherens junction proteins. This leads to increased BBB permeability, leakage of blood components, and movement of immune cells into the brain parenchyma. SARS-CoV-2 may also cross microvascular endothelial cells through an ACE2 receptor-associated pathway. The exact mechanism of BBB dysregulation in COVID-19/neuro-COVID is not clearly known, nor is the development of long COVID. Various blood biomarkers could indicate disease severity and neurologic complications in COVID-19 and help objectively diagnose those developing long COVID. This review highlights the importance of neurovascular and BBB disruption, as well as some potentially useful biomarkers in COVID-19, and long COVID/neuro-COVID.

Lessons Learned in Implementing a Multidisciplinary Long COVID Clinic

The diagnosis and treatment of long COVID patients is challenging. Our aim is to share lessons learned using a multidisciplinary approach within the Veterans Affairs system. Our long COVID clinic is based in primary care but has imbedded rehabilitation specialists, nutrition, whole health, and different specialists within internal medicine. We conducted an extensive work-up to evaluate the presence of end-organ damage, ongoing inflammation, and dysautonomia. Our treatments are based on the prior experience that the Veterans Affairs system has on chronic fatigue syndrome and gulf war illness.

Risk of autoimmune diseases following COVID-19 and the potential protective effect from vaccination: a population-based cohort study

Background

Case reports suggest that SARS-CoV-2 infection could lead to immune dysregulation and trigger autoimmunity while COVID-19 vaccination is effective against severe COVID-19 outcomes. We aim to examine the association between COVID-19 and development of autoimmune diseases (ADs), and the potential protective effect of COVID-19 vaccination on such an association.

Methods

A retrospective cohort study was conducted in Hong Kong between 1 April 2020 and 15 November 2022. COVID-19 was confirmed by positive polymerase chain reaction or rapid antigen test. Cox proportional hazard regression with inverse probability of treatment weighting was applied to estimate the risk of incident ADs following COVID-19. COVID-19 vaccinated population was compared against COVID-19 unvaccinated population to examine the protective effect of COVID-19 vaccination on new ADs.

Findings

The study included 1,028,721 COVID-19 and 3,168,467 non-COVID individuals. Compared with non-COVID controls, patients with COVID-19 presented an increased risk of developing pernicious anaemia [adjusted Hazard Ratio (aHR): 1.72; 95% Confidence Interval (CI): 1.12-2.64]; spondyloarthritis [aHR: 1.32 (95% CI: 1.03-1.69)]; rheumatoid arthritis [aHR: 1.29 (95% CI: 1.09-1.54)]; other autoimmune arthritis [aHR: 1.43 (95% CI: 1.33-1.54)]; psoriasis [aHR: 1.42 (95% CI: 1.13-1.78)]; pemphigoid [aHR: 2.39 (95% CI: 1.83-3.11)]; Graves' disease [aHR: 1.30 (95% CI: 1.10-1.54)]; anti-phospholipid antibody syndrome [aHR: 2.12 (95% CI: 1.47-3.05)]; immune mediated thrombocytopenia [aHR: 2.1 (95% CI: 1.82-2.43)]; multiple sclerosis [aHR: 2.66 (95% CI: 1.17-6.05)]; vasculitis [aHR: 1.46 (95% CI: 1.04-2.04)]. Among COVID-19 patients, completion of two doses of COVID-19 vaccine shows a decreased risk of pemphigoid, Graves' disease, anti-phospholipid antibody syndrome, immune-mediated thrombocytopenia, systemic lupus erythematosus and other autoimmune arthritis.

Interpretation

Our findings suggested that COVID-19 is associated with an increased risk of developing various ADs and the risk could be attenuated by COVID-19 vaccination. Future studies investigating pathology and mechanisms would be valuable to interpreting our findings.

Funding

Supported by RGC Collaborative Research Fund (C7154-20GF).

Pain and Clinical Presentation: A Cross-Sectional Study of Patients with New-Onset Chronic Pain in Long-COVID-19 Syndrome

The aim of this study was to evaluate the characteristics of pain (i.e., pain intensity, pain interference, clinical presentation) in Long-COVID-19 patients and compare the location of pain between successfully recovered COVID-19 patients and healthy matched controls. A cross-sectional case-control study was carried out. Long-COVID-19 patients, age- and sex-matched patients with a history of COVID-19 who had successfully recovered, and healthy controls were included. Outcomes included were pain characteristics (Brief Pain Inventory and Short-Form McGill Pain Questionnaire) and clinical presentation (Widespread Pain Index and Euroqol-5 Dimensions 5 Levels Visual Analogue Scale). Sixty-nine patients with Long-COVID-19 syndrome, sixty-six successfully recovered COVID-19 patients, and sixty-seven healthy controls were evaluated. Patients with Long-COVID-19 syndrome showed greater pain intensity and interference. In addition, they showed worse quality of life and greater widespread pain, with the most frequent locations of pain being the neck, legs, and head. In conclusion, patients with Long-COVID-19 syndrome show a high prevalence of pain, characterized by widespread pain of moderate intensity and interference, with the most frequent locations being the neck, legs, and head, significantly affecting the quality of life of these patients.

Autoimmune Reaction Associated With Long COVID Syndrome and Cardiovascular Disease: A Genetic Case Report

A 35-year-old woman with history of cardiovascular disease presented with shortness of breath, lightheadedness, fatigue, chest pain, and premature ventricular contractions 3 weeks after her second COVID-19 vaccine. Symptoms subsided following catheter ablation and ibuprofen except for chest pain and fatigue, which persisted following ablation and subsequent SARS-CoV-2 infection. The case suggests causal associations between COVID-19 vaccine/infection and recurrence of cardiovascular disease, including long-COVID-like symptoms. (Level of Difficulty: Advanced.).

Phalangeal microgeodic syndrome, COVID-19, and antinuclear antibodies in a child: A case report

Phalangeal microgeodic syndrome (PMS) is a rare rheumatological disease affecting children strongly associated with cold weather. It is considered to be benign and self-limiting, with most cases resolving in warmer months, and no studies have investigated its association to autoantibodies or viral infection. In this peculiar case, a 12-year-old child with the previous COVID-19 infection developed PMS that did not improve in the warm weather and, subsequently, Raynaud's phenomenon and facial rash. With the increasing number of new studies showing the correlation between COVID-19 and autoimmunity, this case report highlights a plausible link between COVID-19, PMS, and autoimmunity in the pediatric population that should be investigated further.

Post-COVID Pain Is Not Associated with Inflammatory Polymorphisms in People Who Had Been Hospitalized by COVID-19

Our aim was to assess the association between four inflammatory polymorphisms with the development of post-COVID pain and to associate these polymorphisms with the clinical pain phenotype in individuals who had been hospitalized by COVID-19. Three potential genotypes of IL-6 (rs1800796), IL-10 (rs1800896), TNF-α (rs1800629), and IFITM3 (rs12252) single nucleotide polymorphisms (SNPs) were obtained from no-stimulated saliva samples from 293 (49.5% female, mean age: 55.6 ± 12.9 years) previously hospitalized COVID-19 survivors by polymerase chain reactions. Pain phenotyping consisted of the evaluation of pain features, sensitization-associated symptoms, anxiety levels, depressive levels, sleep quality, catastrophizing, and kinesiophobia levels in patients with post-COVID pain. Analyses were conducted to associate clinical features with genotypes. One hundred and seventeen (39.9%) patients experienced post-COVID pain 17.8 ± 5.2 months after hospital discharge. No significant differences in the distribution of the genotype variants of any SNPs were identified between COVID-19 survivors with and without post-COVID pain (all, p > 0.47). Similarly, the clinical pain phenotype was not significantly different between patients with and without post-COVID pain since no differences in any variable were observed for any SNPs. In conclusion, four SNPs associated with inflammatory and immune responses did not appear to be associated with post-COVID pain in previously hospitalized COVID-19 survivors. Further, neither of the SNPs were involved in the phenotyping features of post-COVID pain.