In addition to a positive serum ANA, which finding supports a diagnosis of SLE?

A positive serum ANA (antinuclear antibody) test is a common finding in systemic lupus erythematosus (SLE), indicating autoimmune activity. In addition to this, leukopenia is significant because it reflects bone marrow involvement or immune-mediated destruction of white blood cells, which is a hallmark of SLE.

Patients with SLE often experience cytopenias due to conditions such as lupus-specific antibody production that can lead to splenic sequestration and/or peripheral destruction of blood cells. The association of leukopenia with SLE is particularly important in clinical assessments, providing evidence of the disease's impact on the hematologic system.

The other options, while they may occur in various medical conditions, do not specifically support a diagnosis of SLE. Hyperglycemia is more associated with diabetes mellitus or stress responses, thrombocytopenia could indicate other pathologies such as infections or other autoimmune disorders, and elevated potassium typically pertains to renal issues or metabolic imbalances rather than directly correlating with SLE. Thus, leukopenia aligns closely with the typical hematologic manifestations seen in patients with SLE.