Tubulo-interstitial nephritis (TIN) with no glomerular lesions, distal renal tubular acidosis and asteatosis cutis in a patient with systemic lupus erythematosus (SLE): a case report]

We report a 28-year-old woman with systemic lupus erythematosus (SLE) who showed tubulo-interstitial nephritis (TIN) without any glomerular changes. In 1990, she was admitted to our hospital, complaining of anorexia, vomiting and persistent high fever. Laboratory findings showed proteinuria, pancytopenia, hypocomplementemia and positive for antinuclear antibody, anti-DNA antibody, anti-Sm antibody, anti-SSA antibody and anti-SSB antibody. We made a diagnosis of SLE. Furthermore, distal renal tubular acidosis and asteatosis cutis were revealed. The diagnosis of Sj?gren's syndrome was not made. We treated with high-dose prednisolone (60mg/day) and achieved improvement of symptoms and laboratory data. Open renal biopsy showed TIN without any glomerular changes. Predominant TIN is very rare in SLE. We discussed its pathogenesis and relation to the renal lesions of Sj?gren's syndrome.