Renal Tubular Acidosis Type I with Prominent Hypokalemia and Nephrolithiasis as a Presentation of Sjögren’s/Systemic Lupus Erythematosus Disease

Abstract

Female patient, suffering from nephrolithiasis, at the age of 32 was admitted for renal colic caused by a stone obstructing UP junction with left hydronephrosis. Nephrostomy was placed, resulting in brisk diuresis. Severe metabolic acidosis with normal anion gap and urine pH of 6.5 was noted. Potassium level dropped to extremely low level (1.6 mEq/L), causing muscle paralysis and respiratory failure, necessitating mechanical ventilation. The patient was treated by potassium chloride infusion, followed by correction of severe metabolic acidosis by sodium bicarbonate. Diagnosis of distal type renal tubular acidosis type I (dRTA) was made based on normal anion gap metabolic acidosis, alkaline urine, hypokalemia, and nephrolithiasis. Five years later, the patient presented with severe hypoxia, lung opacities, and bronchiolitis obliterans organizing pneumonia which was confirmed by bronchoscopy with lung tissue biopsy. Concurrently, the patient presented with dry mouth, pruritus, skin rash with hypocomplementemia, elevated anti-DNA, anti-Ro, and anti-SmAb. Diagnosis of overlap Sjögren’s/systemic lupus erythematosus disease was done and treatment by hydroxychloroquine, prednisone, and azathioprine was started. Possible presence of Sjögren’s syndrome should be considered in adult patients with unexplained dRTA.

Distal Renal Tubular Acidosis in Patients with Autoimmune Diseases—An Update on Pathogenesis, Clinical Presentation and Therapeutic Strategies

“…Aiming for a better understanding of the disease, we performed a search of the PubMed database using MeSH descriptors (Acidosis, Renal Tubular; Lupus Erythematosus, Systemic; Sjogren’s Syndrome, Systemic Vasculitis, Rheumatoid Vasculitis, Arthritis, Rheumatoid, Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis, Churg-Strauss Syndrome, IgA Vasculitis, Spondylitis, Ankylosing, Cryoglobulins, Hepatitis, Autoimmune, Liver Cirrhosis, Biliary), and we identified 37 individual case reports published since December 2016 with the association of distal renal tubular acidosis and the following autoimmune disorders: SLE, Sjögren’s syndrome, autoimmune hepatitis, primary biliary cirrhosis and rheumatoid arthritis (see Table 1 ) [ 6 , 10 , 11 , 13 , 15 , 16 , 17 , 18 , 20 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. We also identified a case of hereditary autoimmune polyendocrine syndrome (DRTA, hypoparathyroidism, Addison disease), published in a series of cases, which was not included in our analysis, due to the lack of individual data availability [ 39 ].…”

“…Consequently, most of the patients (26 out of 37) presented with symptoms associated with hypokalemia (progressive muscular weakness and eventually hypokalemic periodic paralysis). In a limited number of cases (3 out of 37), hypokalemic paralysis led to respiratory failure, eventually with orotracheal intubation and ventilation [ 20 , 24 , 25 ]. In one particular case, respiratory failure with the need of orotracheal intubation occurred after producing brisk diuresis and consequent severe hypokalemia following nephrostomy for hydronephrosis caused by ureteral lithiasis [ 24 ].…”

“…In a limited number of cases (3 out of 37), hypokalemic paralysis led to respiratory failure, eventually with orotracheal intubation and ventilation [ 20 , 24 , 25 ]. In one particular case, respiratory failure with the need of orotracheal intubation occurred after producing brisk diuresis and consequent severe hypokalemia following nephrostomy for hydronephrosis caused by ureteral lithiasis [ 24 ]. Although symptoms related to hypokalemia were the most frequently reported, these patients had multiple other manifestations.…”

“…Since most of the patients are diagnosed at fertile age, it is also important to mention the obstetrical complications, although these are not frequently reported. In this series of 31 case reports, we identified two patients who had a history of miscarriages or stillbirth, one of them being diagnosed with overlap syndrome (SLE and Sjögren’s syndrome) [ 16 , 24 ]. Another patient was diagnosed with DRTA during pregnancy, which evolved with multiple complications, respectively preterm labor (at 36 weeks of gestation), fetal bradyarrhythmia and fetal growth retardation [ 26 ].…”

“…This suggests that although immunosuppressive therapy has an important effect on preserving or ameliorating renal function and interstitial infiltrate, it might have no effect on treating the hypokalemia and acidosis. Three patients received a combination of azathioprine, prednisone and hydroxychloroquine [ 18 , 24 , 32 ]. In all of these cases, it is mentioned that acidosis and hypokalemia were not ameliorated and the patients remained dependent on oral supplementation with potassium and bicarbonate.…”