C4A and systemic lupus erythematosus: Her medical history included fluctuating non-allergic conjunctivitis and systemic lupus erythematosus (SLE), diagnosed based on a high titer of antinuclear antibodies (1:2560), positivity for anti-double-stranded DNA, SSA, and SSB antibodies, as well as hypocomplementemia (reduced C3 and C4 levels), arthralgia, and cutaneous eruptions.