A special case of recurrent gross hematuria: Answers

Kidney involvement in Wilson's disease: a review of the literature

Wilson's disease (WD) is a rare inherited disease due to the mutation of the ATP7B gene, resulting in impaired hepatic copper excretion and its pathological accumulation in various organs such as the liver, the nervous system, or the kidneys. Whereas liver failure and neuropsychiatric disorders are the most common features, less is known about the renal complications. We conducted a review of the literature to define the characteristics and pathophysiology of kidney involvement during WD. This review shed light on strong evidence for direct copper toxicity to renal tubular cells. Excessive tubular copper accumulation might present with various degrees of tubular dysfunction, ranging from mild hydroelectrolytic and acid-base disorders to complete Fanconi syndrome. Proximal and distal renal tubular acidosis also favors development of nephrolithiasis, nephrocalcinosis, and bone metabolism abnormalities. Indirect complications might involve renal hypoperfusion as occurs in hepatorenal or cardiorenal syndrome, but also tubular casts' formation during acute hemolysis, rhabdomyolysis, or bile cast nephropathy. Acute kidney failure is not uncommon in severe WD patients, and independently increases mortality. Finally, specific and long-term therapy by D-penicillamin, one of the most efficient drugs in WD, can cause glomerular injuries, such as membranous nephropathy, minimal-change disease, and, rarely, severe glomerulonephritis. Altogether, our study supports the need for interdisciplinary evaluation of WD patients involving nephrologists, with regular monitoring of tubular and glomerular functions, to provide adequate prevention of renal and bone involvement.

IgA Nephropathy with Wilson's Disease: A Case Report and Literature Review

The most common glomerulonephritis seen in the world is immunoglobulin A nephropathy (IgAN). It can be primary or secondary associated with various conditions like Chronic Liver disease, Crohn's disease, neoplasms, etc. However, IgAN secondary to Wilson's disease is very rare. A 9 year old boy presented with gross hematuria and proteinuria. He had a history of recurrent jaundice in the past. Ultrasonography (USG) whole abdomen showed altered echotexture of the liver with normal-sized kidneys. An extended workup for liver disease was done, and the diagnosis of Wilson's disease was confirmed with decreased serum ceruloplasmin levels, increased urinary copper, and the Kayser-Fleischer ring. Urine routine microscopy showed numerous red blood cells, few red blood cell casts, and mild proteinuria. Renal biopsy showed IgAN. The patient was started on D-penicillamine. On follow-up at 3 months, he showed complete resolution of proteinuria and hematuria. Thus, we suggest that Wilson's disease should be considered as one of the causes of secondary IgAN in pediatric patients with hematuria, proteinuria with liver dysfunction.

IgA vasculitis with nephritis in cirrhotic Wilson disease: Is there an association?

INTRODUCTION

IgA vasculitis (IgA-V) predominantly involves skin, gastrointestinal (GI) tract, joints, and kidneys. Wilson disease (WD) is a hepatolenticular degenerative disease caused by ATP7B gene mutation.

CASE REPORT

Here we describe an unusual association of IgA-V with nephritis (IgA-VN) in an 11-year-old child with WD. He presented with palpable purpura without arthritis and GI involvement. Renal function was normal. Urinalysis showed microscopic hematuria and tubular proteinuria. Evaluation showed transaminitis, hypoalbuminemia, IgA hyperglobulinemia, and coagulation abnormalities. Serum ceruloplasmin and copper were low and 24-hour urine copper was extremely elevated. Liver biopsy showed stage IV cirrhosis with increased quantitative liver copper content. Skin and renal biopsy showed IgA-positive leukocytoclastic vasculitis and mesangial hyperplasia with IgA deposition, respectively. Quantitative renal copper content was normal. Homozygous pathogenic variant c.3207C>A (p.His1069Gln) of ATP7B was detected. There were no Kayser-Fleischer rings in the eyes, and neuropsychiatric examination was normal. Treatment with zinc and trientine led to normalization of hepatic function and serum IgA level with resolution of the rash and maintenance of renal function.

CONCLUSION

Defective hepatic processing and/or clearance of IgA/IgA immune complexes probably led to the IgA-mediated skin and renal injury. Further such reports will help augment our understanding on the pathophysiology of IgA-VN in WD.

Immunoglobulin A nephropathy secondary to Wilson's disease: a case report and literature review

Immunoglobulin A nephropathy is the most common primary glomerulonephritis worldwide, and it can be associated with liver disease. However, cases of Immunoglobulin A nephropathy secondary to Wilson's disease are very rare. A 20-year-old Japanese man presented with microscopic hematuria, proteinuria, and renal dysfunction. A renal biopsy showed mesangial cell proliferation, immunoglobulin A deposition, and electron-dense deposit in the mesangial areas, all of which are consistent with Immunoglobulin A nephropathy. Computed tomography of the abdomen showed liver atrophy and splenomegaly, and the diagnosis of Wilson's disease was confirmed with decreased serum ceruloplasmin levels, increased urinary copper excretion, Kayser-Fleischer rings and copper deposition in the liver biopsy. The patient was treated successfully with trientine hydrochloride and zinc acetate and showed improvement in renal manifestations. Wilson's disease is a rare cause of secondary Immunoglobulin A nephropathy. We recommend that Wilson's disease should be considered the cause of secondary Immunoglobulin A nephropathy in juvenile patients with hematuria, proteinuria, and splenomegaly and suggest measuring the serum ceruloplasmin concentrations, urinary copper excretion, and evaluating Kayser-Fleischer rings in these patients.