Sarcoidosis and COVID-19: At the Cross-Road between Immunopathology and Clinical Manifestation

Pathophysiological, immunological, and inflammatory features of long COVID

The COVID-19 pandemic continues to cause severe global disruption, resulting in significant excess mortality, overwhelming healthcare systems, and imposing substantial social and economic burdens on nations. While most of the attention and therapeutic efforts have concentrated on the acute phase of the disease, a notable proportion of survivors experience persistent symptoms post-infection clearance. This diverse set of symptoms, loosely categorized as long COVID, presents a potential additional public health crisis. It is estimated that 1 in 5 COVID-19 survivors exhibit clinical manifestations consistent with long COVID. Despite this prevalence, the mechanisms and pathophysiology of long COVID remain poorly understood. Alarmingly, evidence suggests that a significant proportion of cases within this clinical condition develop debilitating or disabling symptoms. Hence, urgent priority should be given to further studies on this condition to equip global public health systems for its management. This review provides an overview of available information on this emerging clinical condition, focusing on the affected individuals' epidemiology, pathophysiological mechanisms, and immunological and inflammatory profiles.

Sarcoidosis detected after COVID‑19 with T‑SPOT.TB positive: A case report

Sarcoidosis is an idiopathic multisystem disorder with unknown etiology. Due to clinical similarities among sarcoidosis, tuberculosis (TB) infection and malignant diseases (such as lymphoma, lung carcinoma and pituitary tumor), the diagnosis of sarcoidosis is challenging. The present report describes a case of sarcoidosis in a 48-year-old male with complaint of chest pain 1 month after Coronavirus disease 2019. The patient underwent whole-body 18F-fluorodeoxyglucose (18F-FDG) PET-CT imaging, which revealed multiple lymphadenopathies throughout the body without lung parenchyma involvement. Biochemical examinations such as T-SPOT.TB test and pathological examination of right supraclavicular lymph node revealed positive T-SPOT.TB but negative Ziehl-Neelsen staining. However, non-caseating epithelioid granulomas were observed in the mediastinal biopsy, indicating the diagnosis of sarcoidosis. The patient was clinically stable, and the symptom of chest pain was gradually relieved without any specific treatment. Outpatient follow-up continued every 3 months. The present case suggested a possible link between coronavirus infection and sarcoidosis, which suggests the advantages of 18F-FDG PET-CT for the detection of sarcoidosis. However, T-SPOT.TB is insufficient for differentiating between sarcoidosis and TB.

Subacute hemorrhagic pericardial tamponade after COVID-19 infection mimicking carcinomatous pericarditis: a case report

Background

Coronavirus disease (COVID-19)-associated acute pericarditis has recently received much attention owing to its high frequency associated with pericardial tamponade (PT), showing unfavorable prognosis. However, early diagnosis and treatment remain challenging in cases of non-specific signs and symptoms.

Case presentation

A 64-year-old man was admitted to our hospital for acute osteomyelitis of the toes and was properly treated with antimicrobial agents. Three days after admission, the patient developed mild COVID-19 without pneumonia, for which early anti-COVID-19 agents were initiated. Nevertheless, the patient developed hemorrhagic PT due to acute pericarditis 2 weeks later, which was confirmed by cardiac magnetic resonance, requiring an urgent pericardiocentesis. Although cytological analysis of the hemorrhagic pericardial fluid strongly suggested adenocarcinoma, the atypical cells were eventually proven to be mesothelial cells with reactive atypia. Furthermore, lymph nodes swelling with abnormal 2-[18F]-fluoro-2-deoxy-D-glucose accumulation on imaging were suggestive of malignancy. However, biopsy examination revealed multiple non-caseating granulomas in the lymph node, unlikely due to malignancy. Eventually, the temporal association of the preceding COVID-19 with the occurrence of subacute PT without other identifiable cause led to a final diagnosis of COVID-19-associated acute pericarditis. With anti-inflammatory and corticosteroids treatment, the patient's symptoms involving the pericardial structure and function were completely resolved along with improvements in size of the affected lymphadenopathies.

Conclusions

We encountered a unique case of COVID-19-associated acute pericarditis exhibiting hemorrhagic PT. This case underscores the residual risk of delayed pericardial involvement even in patients with mild COVID-19 who receive early treatment, and the recognition that COVID-19 may cause various cytomorphological and histological features. Additionally, the importance of considering this rare entity as a cause of hemorrhagic pericardial effusions should be highlighted.

Sarcoidosis-related autoimmune inflammation in COVID-19 convalescent patients

Currently, there are a large number of reports about the development of autoimmune conditions after COVID-19. Also, there have been cases of sarcoid-like granulomas in convalescents as a part of the post-COVID-19 syndrome. Since one of the etiological theories of sarcoidosis considers it to be an autoimmune disease, we decided to study changes in the adaptive humoral immune response in sarcoidosis and SARS-CoV-2 infection and to find out whether COVID-19 can provoke the development of sarcoidosis. This review discusses histological changes in lymphoid organs in sarcoidosis and COVID-19, changes in B cell subpopulations, T-follicular helper cells (Tfh), and T-follicular regulatory cells (Tfr), and analyzes various autoantibodies detected in these pathologies. Based on the data studied, we concluded that SARS-CoV-2 infection may cause the development of autoimmune pathologies, in particular contributing to the onset of sarcoidosis in convalescents.

Approach to COVID-19 in older adults and indications for improving the outcomes

Background: COVID-19 continues to present challenges in the care of older adults with frailty and/or comorbidities and very old patients, who can be hospitalized with severe COVID-19 despite full vaccination. Frailty is a heterogeneous syndrome characterized by an increased aging-related vulnerability due to a reduced physiological reserve and function of systemic organs, and is associated with an impairment of activities of daily living. Frail older adults remain at elevated risk of mortality from COVID-19 compared to older adults without frailty, and some pre-existing risk factors such as malnutrition, prolonged bed rest, and the association with comorbidities can aggravate the SARS-CoV-2 infection. Furthermore, the severity of COVID-19 can impact on long-term functioning of older patients surviving from the infection. Persistent symptoms are another emerging problem of the post-vaccination phase of pandemic, as most patients suffer from chronic symptoms which can become debilitating and affect the daily routine. Aim of this review: In this complex relationship, the evaluation of COVID-19 in vulnerable categories is still a matter of high interest and personalized care plans based on a comprehensive geriatric assessment, tailored interventions; specific therapeutic algorithms among older adults are thus recommended in order to improve the outcomes.

Compartment Syndrome of All Extremities in the Setting of COVID-19-Induced Systemic Capillary Leak Syndrome With Superimposed Myositis

Three years following the pandemic's emergence, COVID-19 has continued to affect much of the symptomatic population with widely varied respiratory complaints, fevers, numerous unexpected prodromal manifestations, and unknown long-term consequences. Scattered cases involving myopathies, rhabdomyolysis, and compartment syndrome have also been reported throughout the pandemic. Some similar cases have been attributed to systemic capillary leak syndrome (SCLS). Here, we report the development of compartment syndrome involving all extremities in a 57-year-old vaccinated female known to have COVID-19. In retrospect, we believe the clinical severity and the patient's sudden deterioration can also be attributed to the lesser-known SCLS. Treatment required fasciotomies of both forearms, arms, and legs. This is the most significantly involved case, leading to survival reported thus far. Lab abnormalities, misleading imaging, and symmetric involvement of all extremities posed a significant challenge to proper diagnosis and treatment. This case serves as a reminder for providers to remain cognizant of neurovascular emergencies during the workup of critically ill patients when the presentation is unrecognized and usual treatments are refractory. Its purpose is also to contribute to the global understanding of and response to COVID-19.

Sarcoidosis Presenting as a Lung Mass in a Patient With COVID-19 Infection: A Case Report

Coronavirus disease 2019 (COVID-19) is a viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which is known to be associated with immune dysregulation and can cause multiorgan dysfunction. Sarcoidosis is another disease associated with increased inflammatory responses due to immune dysregulation which can also affect multiple organs. Although sarcoidosis, like COVID-19 infection, can affect virtually any organ, the lungs are the most commonly affected organs. Sarcoidosis most commonly presents as lung nodules and bilateral hilar lymphadenopathy. Rarely, multiple granulomatous lesions can coalesce and manifest as lung masses, and these often mimic lung cancer. We present a case of a 64-year-old male who presented with shortness of breath and pneumonia-like symptoms for one week and a nasopharyngeal swab for SARS-CoV-2 was positive. Workup revealed a large 6.3×4.7 cm lung mass in the right upper lobe along with enlarged bilateral lymph nodes. A CT-guided lung biopsy was done which revealed non-caseating granulomas containing epithelioid cells. Other causes of granuloma like tuberculosis and fungal infections were ruled out. The patient was managed with low-dose steroids and a follow-up CT scan done after eight months revealed complete resolution of lung mass with minimal mediastinal lymphadenopathy. This is, as far as we are aware, the first case of COVID-19 infection manifesting as a lung mass that was ultimately diagnosed as sarcoidosis.