Differential Diagnosis for Skin Lesions with Retiform Purpura
Given the description of skin lesions as retiform purpura, the differential diagnosis can be expanded and categorized as follows:
- Single Most Likely Diagnosis
- Antiphospholipid Syndrome (APS): This condition is known for its association with retiform purpura, which is a characteristic skin manifestation. APS can cause arterial or venous thrombosis, and the presence of retiform purpura could indicate a thrombotic event in the skin.
- Other Likely Diagnoses
- Disseminated Intravascular Coagulation (DIC): This condition involves both clotting and bleeding and can lead to purpuric lesions due to the consumption of clotting factors and platelets.
- Thrombotic Thrombocytopenic Purpura (TTP): Characterized by thrombocytopenia, microangiopathic hemolytic anemia, renal failure, and neurological symptoms, TTP can present with purpuric lesions.
- Vasculitis: Conditions like cutaneous small vessel vasculitis can present with purpura, including retiform purpura, due to inflammation of the blood vessel walls.
- Do Not Miss Diagnoses
- Meningococcemia: Although less common, this condition can present with purpuric lesions, including retiform purpura, and is critical to identify due to its high mortality rate if not promptly treated.
- Sepsis: Sepsis, especially due to certain bacteria like Neisseria meningitidis, can cause purpuric lesions, including retiform purpura, as part of its presentation.
- Rare Diagnoses
- Calcinosis Cutis: While not typically presenting with retiform purpura, certain forms of calcinosis cutis can lead to skin lesions that might be confused with purpura.
- Livedoid Vasculopathy: A rare condition characterized by recurrent thrombophlebitis and livedo reticularis, which can sometimes present with lesions resembling retiform purpura.
Each of these diagnoses has a unique set of clinical features and diagnostic criteria. The presence of retiform purpura significantly narrows down the differential diagnosis, pointing more towards conditions associated with thrombosis, vasculitis, or coagulopathy. A thorough history, physical examination, and appropriate laboratory tests are essential for making an accurate diagnosis.