Mohammad-Lamine-Debaghine hôspital, Algeria
LAIDOUDI Aicha has completed her PhD at the age of 25 years from Ferhat Abbas University and she is in the postdoctoral studies, Mohamed Maherzi University School of Medicine. She is a doctor in the department of internal medicine, Mohamed Lamine Debaghine Hospital. She is in 5th and latest year of post-doctoral studies.
Introduction:The NITU syndrome is a rare combination characterized by the occurrence of tubulointerstitial nephritis (TIN) and uveitis (U), it is a rare disease of the adolescent and the young woman, its pathogenesis is unknown, autoimmune origin has recently been proposed including humoral and cellular immunity. In general, renal and eye damage tended to resolve with corticosteroid therapy. We report two cases of TINU syndrome occurring in adults in which the recovery of renal function was incomplete despite corticotherapy in the first observation, and immunological disorders which can create differential diagnostic difficulties. Case reports: Observation 1: A 25 year old woman, nurse, admitted to explore asthenia and weight loss of 6 Kg, associated with severe hypertension and acute unilateral anterior uveitis. She was taking no medications. Clinical examination revealed: a blood pressure (BP) of 170/130 mmHg, class II dyspnea (NYHA), a holosystolic heart murmur in the mitral area without heart failure signs, a mucocutaneous pallor but no signs of vasculitis, urine dipstick test finds traces of protein and hematuria; ocular fundus exam found grade I hypertensive retinopathy, the rest of the examination was normal. Biological studies showed kidney failure with GFR of 18.71 ml/mn/1.73m2 , proteinuria was 540 mg / 24h. Erythrocyte sedimentation rate between 37 and 76 mm (3-12) mm/hour. Kidney biopsy with histological examination showed a non caseating granuloma in the interstitial tissue with presence of rare hyaline casts in the kidney tubules, and tubulointerstitial nephritis with granulomatous lesions in the medullary parenchyma. Further exploration was done mainly oriented to sarcoidosis and tuberculosis and the other differential diagnosis was all negative but Quantiferon was 10 times normal with negativity of all other examinations to KB (koch’s bacillus). No other sites of granulomas. The patient responded to corticoid treatment (pulse IV followed by high-dose daily glucocorticoids then gradually tapered off but without normalization. The patient untimely stopped corticosteroids after 4 months of treatment that caused a decreased renal function that required a 2nd pulse then high-dose daily glucocorticoids. Glucocorticoid-sparing was provided by mycophenolate mofetil (MMF). The patient remained well without recurrence of uveitis 2 years later but without complete recovery of renal function which improved gradually with immunosuppressive treatment. Observation 2: A 46 year old patient, without specific personal history, but a mother who died of chronic kidney failure, presented a recurrent anterior uveitis, associated with an increase in serum creatinine; The clinical examination is unremarkable, the urine dipstick showed proteinuria (+), glycosuria: traces; Biological studies showed kidney failure with a GFR of 14 mL / min/1.73m2, inflammatory syndrome, proteinuria of 650 mg /day, research of infectious agents or auto-immunity origin was negative. Renal biopsy showed tubulointerstitial nephritis lesions in subacute stage; biopsy of the salivary glands showed stage III chronic lymphocytic sialadenitis (the Chisholm and Mason classification) without xerostomia, AntiSSA, antiSSB negative. Gallium scintigraphy did not find any signs suggesting a type of sarcoidosis inflammatory. The diagnosis of TINU syndrome was retained after exclusion of other differential diagnosis. The patient received corticosteroid treatment. Serum creatinine improved quickly with normalization 2 months later. The patient remained well without recurrence of the disease 6 years later. Discussion: TINU syndrome diagnosis is based on a combination of the bipolar impairment: renal and eye; and excluding other causes (infectious, drug and autoimmune). The treatment protocol is not yet codified, but corticosteroids at high-dose are first-line treatment of renal disease. In our patients, the presence of TIN in the renal biopsy, recurrent anterior uveitis, no notion of drug intake, the response to corticosteroids and exclusion of other diagnoses, so the diagnostic of TINU syndrome was retained. In the first observation, positivity of Quantiferon is explained by the fact that the TINU syndrome is associated with elevation of serological markers in the absence of their corresponding diseases, in the 2nd observation, the presence of stage III chronic lymphocytic sialadenitis can be explained by these immunological disorders in the absence of Sjogren syndrome. Conclusion: TINU syndrome is a rare entity, the pathogenesis is unknown, and its association with autoimmune diseases suggests its autoimmune origin. TINU syndrome is secondary to immunological disorders as evidenced interstitial infiltrate of the renal parenchyma, the inflammatory disease of the uvea and good response to corticosteroid therapy.