Kidney Week

Abstract: TH-PO504

Clinicopathologic Characteristics, Treatment, and Outcome of Tubulointerstitial Nephritis and Uveitis Syndrome in Children

Session Information

• CKD: Clinical Trials and Tubulointerstitial Disorders
  November 02, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Chronic Kidney Disease (Non-Dialysis)

• 305 CKD: Clinical Trials and Tubulointerstitial Disorders

Authors

• Hayashi, Asako, Hokkaido University Graduate School of Medicine, Hokkaido, Japan

Asako Hayashi,

• Okamoto, Takayuki, Hokkaido University Graduate School of Medicine, Hokkaido, Japan

Takayuki Okamoto,

• Takahashi, Toshiyuki, Hokkaido University Graduate School of Medicine, Hokkaido, Japan

Toshiyuki Takahashi,

• Sato, Yasuyuki, Hokkaido University Graduate School of Medicine, Hokkaido, Japan

Yasuyuki Sato,

Background

Tubulointerstitial nephritis and uveitis (TINU) syndrome is a rare disease, presenting as a combination of tubulointerstitial nephritis and uveitis. A few case-series previously reported good renal prognosis of this syndrome, but long-term prognosis is not known enough in children. To further investigate this syndrome, we report here the clinical features and outcome. All patients followed up at least 24 months (median, 47months; range 24-179).

Methods

Retrospective study of the case records of all patients diagnosed with the TINU syndrome in the Departments of Pediatrics and Medicine of the Hokkaido University Hospital (Sapporo, Japan) from February 1990 through April 2017.

Results

We report here the clinical features and outcome of 20 patients (female 12, F/M ratio: 3:2), aged 9 to 14 years at diagnosis (median, 13.0) with TINU syndrome. The initial symptoms were visual impairment in sixteen patients (80%) and deterioration of health status in six patients (30%). The median estimated glomerular filtration rate (eGFR) at diagnosis was 99.8 mL/min per 1.73m² (range 59.7-117.4) and deteriorated renal function (eGFR <90 mL/min per 1.73m²) was observed in 9 patients (30%). An increase in urinary β₂-microglobulin levels was noticed at the initial checkup in all patients. Topical and oral corticosteroids were prescribed to 15patients (75%) and Mizoribine or Methotrexate therapy was required in 2 patients (10%). After 24 months follow-up, the median eGFR was 111.4ｍL/min per 1.73m² (range 80.1-127.9). In three patients (15%) decreased eGFR<90 mL/min per 1.73m² after 24 months but the renal function of all patients was normalized at the latest checkup. Urinary β₂-microglobulin excretion gradually declined but was slightly elevated in 11 patients (55%) at 24 months. Recurrent or exacerbating uveitis was seen in ten patients (50%). On the other hand, TIN is not recurrence.

Conclusion

The TINU syndrome should be considered in the differential diagnosis of patients presenting with visual and renal manifestations. The presence of increase in urinary β₂-microglobulin levels may be of some help for the early discovery of recognition of TINU syndrome. In children and adolescents with this syndrome, the long- term prognosis of TIN is good, but uveitis often relapse.