Distal renal tubular acidosis and severe hypokalemia: a case report and review of the literature

Abstract

Background Distal renal tubular acidosis is a relatively infrequent condition with complex pathophysiology that can present with life-threatening electrolyte abnormalities. Case presentation We describe a case of a 57-year-old Caucasian woman with previous episodes of hypokalemia, severe muscle weakness, and fatigue. Upon further questioning, symptoms of dry eye and dry mouth became evident. Initial evaluation revealed hyperchloremic metabolic acidosis, severe hypokalemia, persistent alkaline urine, and a positive urinary anion gap, suggestive of distal renal tubular acidosis. Additional laboratory workup and renal biopsy led to the diagnosis of primary Sjögren’s syndrome with associated acute tubulointerstitial nephritis. After potassium and bicarbonate supplementation, immunomodulatory therapy with hydroxychloroquine, azathioprine, and prednisone was started. Nonetheless, her renal function failed to improve and remained steady with an estimated glomerular filtration rate of 42 ml/min/1.73 m 2 . The literature on this topic was reviewed. Conclusions Cases of renal tubular acidosis should be carefully evaluated to prevent adverse complications, uncover a potentially treatable condition, and prevent the progression to chronic kidney disease. Repeated episodes of unexplained hypokalemia could be an important clue for diagnosis.

Renal Tubular Acidosis and Management Strategies: A Narrative Review

“…Patients with distal RTA typically develop hyperchloremic, hypokalemic metabolic acidosis with a normal anion gap [ 11 , 14 ]. In general, most patients develop hypokalemia as decreased distal secretion of H + via H + -ATPase or H + /K + -ATPase ultimately causes decreased K + reabsorption (i.e., renal K + wasting) [ 13 , 15 ]. If H + /K + -ATPase is primarily affected, then less K + will be reabsorbed.…”

Efficacy and safety of an innovative prolonged-release combination drug in patients with distal renal tubular acidosis: an open-label comparative trial versus standard of care treatments

“…Hypokalemia may persist in some patients despite sustained correction of systemic acidosis with SoC alkali therapy [ 26 , 27 ] and these patients require potassium supplementation to maintain normal plasma potassium levels [ 28 ]. This justifies the treatment with potassium salts in ADV7103, which allows increasing plasma potassium without risk of hyperkalemia.…”

Renal Tubular Acidosis Causing Acute Hypokalemic Paralysis in Systemic Lupus Erythematosus: Sjogren’s Syndrome Overlap

“…The exact pathophysiology by which autoimmune conditions cause dRTA is not completely understood and is likely a multifactorial process. Studies have indicated that the reduced secretion of hydrogen ions (H+) in patients with SS maybe because of the downregulated expression of vacuolar H+ATPase in Aintercalated cells of the distal renal tubules [15]. Immunoglobulin G (IgG) autoantibodies against different protein targets involved in acid secretion cells have also been reported, however, it remains unclear whether the antibodies trigger the initial damage or are formed as a result of exposure of intracellular epitopes to B cells from the preceding cell damage [15].…”