LAUSR

Tubulointerstitial nephritis (TIN) is an inflammatory disorder in renal tubules and interstitium without the involvement of glomerular lesions.1 TIN is often induced by drugs and infections, but idiopathic or systemic disease−related forms have also been observed.2 Primary biliary cirrhosis (PBC) is an immune-mediated chronic and progressive cholestatic liver disease.3 Laboratory data show increased serum values of alkaline phosphatase, γ-glutamyl transpeptidase, and IgM. The hallmark of the disease is the circulating antimitochondrial antibody (AMA). PBC is often associated with extrahepatic autoimmune disorders, such as Sjogren syndrome, thyroid disorders, systemic sclerosis, and rheumatoid arthritis.4 Although distal renal tubular acidosis (RTA) has been observed in 33% to 60% of PBC patients,5, 6 TIN and subsequent Fanconi syndrome are relatively rare.7 We report herein a case of TIN associated with asymptomatic PBC, which was diagnosed after 4 years of treatment for TIN and Fanconi syndrome.