A child with tubulointerstitial nephritis and uveitis (TINU) syndrome

Abstract

Tubulointerstitial nephritis and uveitis syndrome is an uncommon disease, probably underdiagnosed in clinical practice. Its aetiology and pathogenesis remain unknown. This syndrome is defined by an association of uveitis and tubulointerstitial nephritis, with no evidence of systemic disease or infection that might cause both ocular and renal inflammation. Renal and ocular manifestations may not occur simultaneously, making the diagnosis even more challenging. Treatment includes topical and oral corticosteroids. Renal involvement usually resolves spontaneously with full recovery of kidney function, however uveitis can persist or recur years after its initial presentation. We report a case of a 13-year-old girl with tubulointerstitial nephritis and uveitis syndrome.

An Adolescent Girl with Tubulointerstitial Nephritis and Uveitis (TINU) Syndrome

“…Uveitis often presents with dryness, eye pain, and visual changes, as was seen in our patient [8]. It is most commonly bilateral non-granulomatous anterior uveitis, although alternating or unilateral uveitis may also occur [7].…”

“…Findings such as fever, myalgia, arthralgia, abdominal pain, anorexia, and headache may be present. However, some patients have more specific manifestations of renal failures, such as flank pain, polyuria, hematuria, and proteinuria [8]. There are currently no specific laboratory findings unique to TINU syndrome; however, increased urinary excretion of ß2microglobulin in combination with a decreased GFR may be the most predictive laboratory evidence for tubulointerstitial nephritis in TINU syndrome [3].…”

“…Interestingly, the underlying cause of anemia, abdominal pain, and anorexia was never determined in our patient. It is possible that these symptoms were unrelated to TINU syndrome; however, given that these symptoms have been present in other cases of TINU syndrome [8], further understanding of the systemic manifestations of TINU syndrome is warranted.…”

“…Our patient returned to normal kidney function within three months after a relatively short course of systemic prednisone. Uveitis may be chronic and tends to recur in at least half of patients with TINU syndrome, even up to 10 years after initial diagnosis [8]. In the more refractory cases, immunosuppressive agents such as methotrexate, mycophenolate mofetil, and cyclosporine may be used [12].…”

Tubulointerstitial nephritis and uveitis syndrome (TINU) following COVID-19 vaccination

“…However, the uveitis may become chronic and renal compromise may evolve into permanent renal insufficiency. 25 The course of renal disease appears to be independent from the ocular disease. 22 The uveitis may recur and often persists longer than the renal disease, which rarely recurs.…”