Chronic hypokalemia: The hidden connection to early systemic lupus

Currently, hypokalemia is managed with potassium supplements; however, there are some rare cases where it can hint towards autoimmune diseases such as systemic lupus erythematosus (SLE). The purpose of this case is to bring attention to the diagnostic difficulty of SLE in the absence of typical mucocutaneous features.

The symptoms included weakness and swelling of the legs. The patient's history revealed persistent chronic hypokalemia over a 4-year period, during which she was treated with potassium supplements, yet without any primary cause being identified.

A comprehensive evaluation found both hematological and renal abnormalities. Notably, despite the lack of classic dermatological signs of lupus, she scored 23 on the European League Against Rheumatism/American College of Rheumatology scoring system. She also screened positive for autoimmune disorders with a significant elevated antinuclear antibody profile including high lupus-specific autoantibodies. Subsequent bone marrow evaluation ruled out other hematological malignancies. Considering all the findings, she was diagnosed with SLE.

She was treated with corticosteroid therapy, consistent with her diagnosis and forming part of the prescribed standard immunosuppressive treatment regimen.

The patient demonstrated significant clinical improvement with regard to her symptoms and her potassium levels. She remained stable in further follow-up.

This case illustrates the importance of very active investigation of the cause of persistent hypokalemia and a multidisciplinary collaboration. Autoimmunity should be considered in chronic electrolyte derangements, particularly in the presence of some blood or kidney problem. SLE is one of the conditions that can be diagnosed and treated early for better clinical outcome.