Why does the lupus malar rash spare the nasolabial folds?
Malar rash (also known as the “butterfly rash,”) is an acute manifestation of lupus (SLE) seen in over 50% of patients. It is a bilateral, erythematous maculopapular rash which spares the nasolabial folds. The rash will last anywhere from days to weeks, and it can be painful/ itchy. It is a photosensitivity phenomenon.
Suspected Mechanism: the nasolabial folds are a relatively UV protected surface and therefore less affected.
Fitzpatrick’s Color Atlas and Synopsis of Clinical Dermatology, 8e. Klaus Wolff, Richard Allen Johnson, Arturo P. Saavedra, Ellen K. Roh. THE SKIN IN IMMUNE, AUTOIMMUNE, AUTOINFLAMMATORY, AND RHEUMATIC DISORDERS.