UE 1 - Sarcoïdose et granulomatose

Sarcoïdose et granulomatose

• Définition: A disease with potential involvement of multiple organs characterized by granulomas, which are collections of immune cells. Epithelioid and giant cells are hallmarks, unlike tuberculosis, which has caseous necrosis. Etiology remains undetermined.

Épidémiologie

• Prevalence: Variable, not rare. Higher in northern Europe, and among African-Americans.
• Age of onset: Typically between 20 and 50 years old, but possible at any age.
• Sex ratio: Balanced.

Physiopathologie

• Inflammation progression (especially in the lungs): Characterized by granuloma formation, triggered by a diverse array of infectious or non-infectious, endogenous or exogenous agents. Challenges in clearing these agents lead to strong immune response via cytokine/chemokine production. Key players include T cells, particularly CD4+ T, and inflammatory cytokines like TNF-alpha and IL-2.

Diagnostic

• Multifaceted approach: Diagnostic relies on a triad of clinical, laboratory, and imaging findings. Histological confirmation (granuloma with no caseous necrosis). Differential diagnosis is critical. Löfgren syndrome (a relatively mild form) doesn't need these three factors for diagnosis.
• Forms: Varied presentations, ranging from asymptomatic to a systemic disease.

Diagnostics Differentiels

• Infectious causes : Tuberculosis, leprosy, various bacterial, fungal, or parasitic infections.
• Other Inflammatory causes: Conditions such as Wegener's granulomatosis, Crohn's disease, and certain malignancies.
• Non infectious causes : Environmental factors (like silica, beryllium) or malignancies

Atteintes d'organes

• Pulmonary involvement: A frequent finding (90%) with various stages in X-Rays shown at a later page.
• Other organ systems: Cutaneous (skin), ocular, neurologic, cardiac, and other systems (renal, salivary glands) can be affected. Frequency varies.
• Additional observations: Presence of symptoms like skin rashes, eye inflammation, or joint pain are also noted as potential presentations of the syndromes.

Diagnostic Markers

• Blood tests: Normal inflammatory markers, except for possible lymphopenia (due to immune cell sequestration) and raised calcium levels (due to cytokine release). Other changes in some parameters are also noted

Treatment

• Asymptomatic cases / mild cases: No treatment initially but ongoing monitoring.
• Significant symptoms: Corticosteroids are the initial treatment approach. Other immunosuppressants like methotrexate may be necessary in severe/chronic circumstances.
• Important Considerations: No vitamin D supplementation concurrently with corticosteroids.

Découvrez les caractéristiques de la sarcoïdose, une maladie inflammatoire qui peut affecter plusieurs organes. Ce quiz aborde la définition, l'épidémiologie, la physiopathologie, et les méthodes diagnostiques de cette condition. Testez vos connaissances sur cette maladie complexe et ses implications.