MYRIAD PRESENTATIONS OF AN UNCOMMON DISEASE

Introduction:

IgG4 disease is a multisystemic fibro-inflammatory condition with of unknown etiology having characteristic histopathological features. The disease has protean clinical manifestations as it can affect any organ system. The 2019 American college of Rheumatology/ European League against Rheumatism has given classification criteria for IgG4 related disease. Renal involvement during the course of IgG4 related disease occurs in approximately 15% of patients. We hereby present a case series of IgG4-RD with varied clinical presentations.

Methods:

Retrospective observational case series

Case 1

A 26-year lady with symptoms of acute gastroenteritis with acute kidney injury with hypercalcemia. Symptomatic improvement was seen on conservative management, however, patient had persistent AKI. Her kidney biopsy was done which was diagnostic of IgG4 disease. Hypercalcemia in IgG4 disease is rare with only few case reports across world.

Case 2

A 39-year male presented with hypertension, deranged renal function parameters, albumin-globulin ratio reversal and sub-nephrotic range proteinuria. His detailed workup was done. On renal biopsy, he was found to have IgG4 disease.

Case 3

A 39-year male presented with history of asthma, hypertension, active urine sediments and sub-nephrotic range proteinuria. Provisional impression of an indolent glomerulonephritis was kept. After renal biopsy, a diagnosis of IgG4 disease was made.

Case 4

A 46-year female presented with symptoms of obstructive uropathy. Her imaging showed features of retroperitoneal fibrosis causing bilateral hydroureteronephrosis. Further workup showed high serum IgG4 levels.

Results:

In all the above cases, the diagnosis of IgG4 disease was made and the patients showed good clinical and biochemical response to treatment with steroids and mycophenolate mofetil.

Conclusions:

IgG4 related disease is an uncommon disease. Most patients present with extrarenal manifestations. However, over the recent years, renal involvement has been increasingly discovered. Keeping a low threshold for kidney biopsy and serum IgG4 levels estimation in suspected patients can reveal many undiagnosed cases.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.