Idiopathic Hypocomplementaemic Tubulointerstitial Nephritis

Background: Tubulointerstitial nephritis (TIN) is a common cause of kidney injury typically seen in association with drug exposure, infection or autoimmune diseases. However, TIN with interstitial immune complex deposition, without glomerular injury, is rarely observed. Case: We report a case of a 64-yearold Indian woman admitted for dialysis-requiring renal failure, without involvement of other organs. Urinalysis showed blood 3+ and 24h proteinuria of 1.5 g. Renal ultrasound revealed normal sized kidneys with loss of parenchymal-sinus differentiation. Laboratory tests disclosed low C3, positive ANA but negative anti-dsDNA, SSA and SSB. Serum protein electrophoresis was normal. The renal biopsy showed tubulointerstitial nephritis with positive immunoglobulin staining involving the interstitium and tubular basement membrane with glomerular sparing. The patient started prednisolone (1mg/kg/day) without recovery of the renal function. Conclusion: Idiopathic hypocomplementaemic tubulointerstitial nephritis is a rare disease with few cases described in the literature. To our knowledge this is the first case reported in Portugal.

Henoch-Schönlein Purpura Associated with Pulmonary Adenocarcinoma

Introduction: The Henoch-Schönlein purpura (HSP) is an immunoglobulin A (IgA)-mediated smallvessel systemic vasculitis, rare in adults. The association with solid tumours has been described, especially with lung cancer. Case Report: We present the case of a 60-year-old Caucasian male, diagnosed with lung adenocarcinoma that underwent surgical resection without (neo)adjuvant theraphy. Two months latter he was admitted for abdominal pain, purpuric rash on his lower extremities and acute kidney injury, with serum creatinine (Scr) of 2 mg/dl. Urinalysis revealed haematuria and 24h proteinuria (P24h) of 1.5 g. The serum protein electrophoresis, complement components C3 and C4, circulating immune complexes, cryoglobulins, ANCA, ANA, anti-dsDNA and the remaining immunologic study as screening for viral infections (HCV, HBV and HIV) were negative. Renal ultrasound was normal and kidney biopsy revealed mild mesangial proliferation; 2 cellular glomerular crescents and 1 fibrinoid necrosis lesion; large amounts of red blood cell casts; lymphocytic infiltration in the intertubular interstitial capillaries; moderate arteriolar hyalinosis. Immunofluorescence demonstrated mesangial and parietal deposits of IgA. The diagnosis of HSP was assumed, and the patient started prednisolone 1 mg/kg/day. Ten months after diagnosis the patient’s baseline Scr is 1.4 mg/dl with P24h of 0.18g, without haematuria. Conclusion: Although this is a rare association and the exact mechanism behind the disease is yet unknown, physicians should be aware of it. The early recognition and treatment may prevent renal disease progression.