A 40-year-old male patient presented to the dermatology OPD with complaints of a characteristic rash over the face along with fever, ahralgia and moderate chest pain. Patient gave history of using some drug for 3 months. On examination, there was no CNS involvement. Lab findings revealed normal urine r/m studies and normal RFTs. ANA and anti-histone antibody titres were found to be raised. Which of the following mechanisms is most likely implicated in the above disease: -
High-Yield Explanation
This is a case of Drug induced Lupus. More common in females. Presents with the characteristic malar skin rash. Along with serositis, most commonly pleuritis. Kidney and CNS are rarely involved. Titres of anti-histone Abs are increased. It is a type 3 hypersensitivity reaction. It is associated with HLA-DR2 Image A shows Type 1 hypersensitivity reaction Image B shows Type 2 hypersensitivity reaction Image C shows Type 4 hypersensitivity reaction