Sarcoidosis and COVID-19: Unmasking a Complex Connection


Sarcoidosis is a complex multisystem inflammatory disease characterized by the presence of non-necrotising granulomas, consisting of epithelioid cells and lymphocytes.

The precise cause of this condition remains elusive, but it is believed to involve immune cross-reactions in genetically susceptible individuals.

Sarcoidosis-like reactions have also been observed in various contexts, such as malignancies, occupational exposures, and adverse reactions to immunotherapy drugs. However, a new and intriguing link between COVID-19 and sarcoidosis has emerged, prompting further exploration into the potential relationship between these two conditions.

A Potential Trigger: COVID-19

The onset of the COVID-19 pandemic has raised questions about whether the virus, SARS-CoV-2, may serve as a trigger for sarcoidosis in some individuals. Several cases have been reported suggesting that COVID-19 infection may be associated with the development of sarcoidosis-like reactions. While the exact mechanisms underlying this connection remain unclear, it is essential to investigate further to better understand the potential implications for clinical practice.

Case Reports

Several case reports have documented the emergence of sarcoidosis-like symptoms following COVID-19 infection. These cases provide insight into the possible link between the two conditions. Notably, some of these cases involve cutaneous sarcoid-like reactions, which are skin manifestations consistent with sarcoidosis.

In two instances, middle-aged Caucasian women experienced these reactions 2-4 weeks after contracting SARS-CoV-2, and skin biopsies confirmed the presence of granulomatous panniculitis. In both cases, spontaneous improvement was observed within one month, suggesting a possible post-infectious phenomenon.

Another case report described Lofgren syndrome in a 30-year-old Caucasian male, occurring three weeks after presumed SARS-CoV-2 infection. A skin biopsy confirmed the presence of non-necrotising granulomata, further linking COVID-19 to sarcoidosis-like reactions.

Furthermore, Mertz and colleagues reported three cases of presumed SARS-CoV-2 infection presenting with sarcoid-like symptoms approximately one month post-infection. These cases ranged from biopsy-confirmed non-necrotising granulomas in cervical lymph nodes to a clinical diagnosis of isolated erythema nodosum with no other explanation.

A more complex case involved a middle-aged Caucasian male who developed pulmonary sarcoidosis five months after discharge from a prolonged ICU stay due to COVID-19. Radiographic findings and core lung biopsies suggested the presence of sarcoidosis, leading to steroid therapy to manage ongoing respiratory symptoms.

The Pathophysiology

Understanding the pathophysiological connection between COVID-19 and sarcoidosis-like reactions is challenging. However, several theories have been proposed. One theory relates to the renin-angiotensin system (RAS), which is negatively regulated by ACE2. SARS-CoV-2 has been shown to reduce pulmonary ACE2 expression, potentially contributing to the inflammatory response and cytokine storm seen in COVID-19.

Sarcoidosis is also associated with elevated circulating ACE levels. However, it is unclear whether increased ACE levels stimulated by human coronaviruses could potentially induce granuloma formation.

There are also similarities in immune features between severe COVID-19 and sarcoidosis, particularly the ‘cytokine storm’ characterized by elevated serum levels of inflammatory cytokines. Nevertheless, most post-COVID-19 sarcoid-like reactions have occurred in patients with mild disease, complicating this hypothesis.

Another theory focuses on cell death pathways, specifically autophagy, which is defective in sarcoidosis. Increased levels of angiotensin II associated with coronavirus infections may negatively regulate autophagy, potentially aiding the virus in hijacking this intracellular system to facilitate its own replication.

Comprehensive Guide to Treating Sarcoidosis: A Multifaceted Approach

Sarcoidosis is a rare but complex inflammatory disease that can affect various organs in the body, most commonly the lungs and lymph nodes. Although there is no known cure for sarcoidosis, there are numerous treatment options available to manage its symptoms and improve the patient’s quality of life. In this comprehensive guide, we will explore the various aspects of treating sarcoidosis, including medications, lifestyle modifications, and supportive therapies.

Understanding Sarcoidosis

Before delving into treatment, it’s crucial to have a clear understanding of sarcoidosis. This condition is characterized by the formation of granulomas, which are clumps of immune cells, primarily in the lungs, lymph nodes, and other organs. The exact cause of sarcoidosis remains unknown, and its severity varies from person to person. Treatments aim to control inflammation, reduce symptoms, and prevent organ damage.

  • Medication-Based Treatments

a. Corticosteroids:

  • The first-line treatment for sarcoidosis is typically corticosteroids, such as prednisone.
  • These drugs help reduce inflammation by suppressing the immune response.
  • Dosages are individualized based on the severity of the disease and patient response.
  • Prolonged corticosteroid use may lead to side effects, so the lowest effective dose is recommended.

b. Immunosuppressive Medications:

  • In cases where corticosteroids are ineffective or have severe side effects, other immunosuppressive medications, like methotrexate or azathioprine, may be prescribed.
  • These drugs help regulate the immune system to reduce inflammation.

c. Biological Therapies:

  • Biological drugs, such as TNF-alpha inhibitors (e.g., infliximab), are sometimes used in severe cases where other treatments have failed.
  • These medications target specific molecules in the immune system.
  • Monitoring and Assessment

Regular check-ups with a healthcare provider are essential to monitor the progress of the disease and adjust treatment plans as needed. These assessments may include:

  • Pulmonary function tests to evaluate lung function.
  • Imaging studies (X-rays, CT scans, or MRIs) to monitor organ involvement.
  • Blood tests to check for inflammation markers.
  • Biopsies to assess granuloma formation and disease progression.
  • Symptomatic Relief

a. Pain Management:

  • Sarcoidosis can cause pain and discomfort, which may be alleviated with over-the-counter pain relievers or prescription medications as needed.

b. Fatigue Management:

  • Chronic fatigue is a common symptom of sarcoidosis. Adequate rest, balanced nutrition, and lifestyle adjustments are key to managing fatigue.

c. Skin Care:

  • Sarcoidosis can affect the skin. Moisturizers, topical steroids, and UV light therapy can help manage skin symptoms.
  1. Lifestyle Modifications

a. Smoking Cessation:

  • Smoking can worsen sarcoidosis symptoms, particularly those affecting the lungs. Quitting smoking is vital.

b. Environmental Factors:

  • Reducing exposure to environmental irritants, such as dust, pollution, or certain chemicals, can help prevent flare-ups.

c. Healthy Diet:

  • A well-balanced diet with plenty of fruits, vegetables, and whole grains can boost overall health and immune function.
  • Supportive Therapies

a. Pulmonary Rehabilitation:

  • For those with lung involvement, pulmonary rehabilitation programs can improve lung function and overall well-being.

b. Support Groups:

  • Joining a sarcoidosis support group can provide emotional support and valuable insights into managing the disease.

c. Vaccinations:

  • Staying up-to-date with vaccinations is crucial to protect against infections, which may exacerbate sarcoidosis symptoms.


The connection between COVID-19 and sarcoidosis-like reactions raises important questions in the field of medicine. Although the exact pathophysiology remains unclear, the increasing number of case reports suggests that this is a clinical phenomenon that deserves further investigation.

Clinicians should consider post-COVID-19 sarcoidosis in their differential diagnosis, as it may represent a treatable cause of persistent symptoms in some patients. As our understanding of these conditions continues to evolve, it is crucial to explore their relationship further and its potential impact on patient care.

reference link :


Please enter your comment!
Please enter your name here

Questo sito usa Akismet per ridurre lo spam. Scopri come i tuoi dati vengono elaborati.