Hypokalemic Paralysis as Primary Presentation of Fanconi Syndrome Associated With Sjögren Syndrome

Abstract

Hypokalemic paralysis is a rare presentation of Fanconi syndrome (FS) caused by Sjögren Syndrome (SS). We describe a 39-year-old man who manifested flaccid paralysis of 4 limbs. Laboratory investigations showed profound hypokalemia (1.6 mmol/L) with renal K wasting, hyperchloremic metabolic acidosis with positive urine anion gap, hypophosphatemia with hyperphosphaturia, hypouricemia with hyperuricosuria, normoglycemic glycosuria, and abnormal serum creatinine concentration 2.2 mg/dL. A thorough survey for the cause of FS revealed that he had xerophthalmia and xerostomia accompanied by high anti-Ro antibody, positive Schirmer test, and delayed saliva excretion on sialoscintigraphy, confirming the diagnosis of SS. Potassium citrate, active vitamin D3, and high phosphate diet for his FS coupled with mycophenolate mofetil for SS resolved clinical symptoms and ameliorated renal function. Early recognition of HP due to the underlying SS-related FS with prompt therapy not only could terminate potentially life-threatening hypokalemia, but also improve renal outcome.

Ectopic germinal center and megalin defect in primary Sjogren syndrome with renal Fanconi syndrome

“…Fanconi syndrome, general dysfunction of the proximal tubule, is a relatively rare clinical manifestation of pSS. By searching PubMed with ((Sjogren syndrome) or (autoimmune epithelialitis)) and ((renal tubule) OR Fanconi), about 20 cases were identified [6, 21–35]. Wang et al [6] and Shi and Chen [33] have summarized SS-related Fanconi syndrome cases that had been reported.…”

“…Fanconi syndrome, the result of proximal tubule epithelial cell (PTEC) injury leading to proximal RTA (type II RTA), hypophosphatemia, hypouricemia, aminoaciduria, glycosuria and urine loss of low molecular weight proteins, is a rare manifestation of pSS. To date, fewer than 20 cases have been reported and the underlying pathogenesis or mechanism remains unclear [6]. …”

Attending Rounds

“…Nine of these patients presented with hypokalemic paralysis (16). Other reports have also described patients with Sjö gren syndrome and mixed DRTA and Fanconi syndrome with hypokalemia that ranged from very severe to more mild (17).…”

“…Corticosteroids and less frequently other immunosuppressives are used successfully to treat Sjö gren syndrome flares, including renal failure associated with this syndrome (16,23). The effect of immunosuppressives on tubular dysfunction, including RTA, is variable and most patients require long-term treatment with alkali and potassium supplementation (17,22). Rituximab has been used in a small number of patients with severe Sicca syndrome and only rarely in patients with renal involvement (23,24).…”

An uncommon presentation of Sjögren's syndrome and brucellosis

“…Common renal abnormalities include urine concentrating defect, tubular proteinuria, hypokalemia, distal RTA, and renal function impairment [1,4]. Although a defect in distal renal tubular function is common, a generalized proximal defect as FS is rarely reported in SS [5,6]. The exact mechanisms by which generalized proximal tubular defect as FS is caused in SS remain obscure.…”