A skin biopsy from a patient with discoid lupus erythematosus (DLE) shows the 'lupus band' on DIF. This band consists of:
- A IgA and C3 in a granular pattern at the DEJ
- B Linear IgG along the BMZ
- C IgG, IgM, IgA and C3 in a granular band at the DEJ ✓
- D IgM globules (civatte bodies) throughout dermis
Correct answer: C. IgG, IgM, IgA and C3 in a granular band at the DEJ
Explanation
The lupus band (lupus band test, LBT) shows granular deposition of multiple immunoreactants—IgG, IgM, IgA, C3 (and sometimes C1q and fibrinogen)—at the dermoepidermal junction in affected skin of DLE patients. In SLE, it can also be found in non-lesional sun-exposed or even non-sun-exposed skin. The multi-immunoreactant granular pattern distinguishes it from bullous pemphigoid (linear IgG) or LABD (linear IgA).
Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.