A Case Report of Renal Tubular Acidosis Type 1 without Glomerular Disease in an Adolescent with Pediatric-onset Systemic Lupus Erythematosus

Abstract

Introduction: Between 50-75% of children and adolescents with systemic lupus erythematosus (SLE) experience kidney involvement within the first year of diagnosis. The gold standard for diagnosing renal involvement in SLE is a renal biopsy. It is uncommon for SLE to cause isolated tubular involvement without any glomerular disease.Case Presentation: We report an adolescent girl with a known history of systemic lupus erythematosus who presented to the emergency department with progressively worsening weakness. The diagnosis revealed that she had distal renal tubular acidosis (RTA) without any glomerular disease. Her history of nephrocalcinosis and kidney stones on renal ultrasound is most consistent with distal renal tubular acidosis diagnosis.Conclusion: This case highlights the importance of considering renal tubular acidosis in lupus patients who experience recurrent hypokalemic episodes. When a patient presents with a normal anion gap metabolic acidosis and hyperchloremia, without evidence of gastrointestinal HCO3 loss or absorption of exogenous acid, renal tubular acidosis (RTA) should be considered.

Keywords

• renal tubular acidosis
• systemic lupus erythematosus
• tubular involvement
• nephrocalcinosis