Controversy regarding paracetamol- and codeine phosphate-induced acute tubulointerstitial nephritis-uveitis (TINU) syndrome.

Firstly, it is controversial to define the second case as tubulointerstitial nephritis (TIN) or TINU syndrome due to lack of either histopathological analysis, or renal failure or uveitis. Despite spontaneous regression of renal findings, it is invalid to diagnose TIN without a biopsy. A similar clinical course may be seen in various other renal disorders related to tubules. It has been reported that β2 microglobulin is markedly elevated in almost every case tested in TINU syndrome, and looking for evidence of such elevation may be useful in cases where renal biopsy is not indicated2. Krebs von den Lunge-6 (KL-6) glycoprotein in serum or renal biopsy may also be a valuable tool in the diagnosis and follow-up of TINU syndrome3. The authors may confirm the diagnosis with these methods. Additionally, patients may be regarded as TINU cases when an actual attack occurs, rather than in instances where there is only a potential risk for development of uveitis in the future.