THE ROLE OF RITUXIMAB IN ANTI-GBM: CASE REPORT

Introduction:

Anti-glomerular basement membrane is an autoimmune disease that primarily affects the renal capillaries and alveoli, causing rapidly progressive kidney disease and alveolar hemorrhage. The initial treatment as a cornerstone is based on plasma exchange at a dose of 50 ml/kg with albumin in addition to cyclophosphamide and pulses of methylprednisolone. However, other treatments have proven attractive as they have been studied. It has been found that the use of Rituximab, an anti-CD-20 monoclonal antibody, as an added treatment makes antibodies negative more quickly. The use of immunoadsorption and plasma exchange with filters such as Immusorba-TR350® is also being studied. Case reports have found out, that treatment with mycophenolic acid has been successful in patients with anti-GBM antibodies. The case of a patient diagnosed with anti-GBM who received treatment with Rituximab is presented.

Methods:

A 31-year-old man went to the emergency department for hematuria and hemoptysis. History of Hodgkin Lymphoma 10 years ago treated with chemotherapy not specified. He was admitted for 1 month with hematuria, nausea and vomiting, and 3 days prior to admission hemoptysis presented. Paraclinical parameters on admission: hemoglobin 10.5 gr/dL, creatinine 11 mg/dL, BUN 62 mg/dL and metabolic acidosis. Chest X-ray: with data of alveolar hemorrhage, urinary sediment with acanthocytes, protein in 24-hour urine 16.9 gr. MPO and PR3 antibodies were negative, complement was normal and anti-dsDNA was negative. Anti-MBG is suspected with a positive antibody result of 105.37 UR/mL (0-20 UR/mL). Management was started with cyclophosphamide 1gr, pulses of methylprednisolone 1gr/daily for 3 doses, then prednisone 60 mg daily and therapeutic plasma exchange with 5 daily exchanges. The patient receives Rituximab 500 mg IV for 3 weekly doses. There was a significant improvement of symptoms (hematuria and hemoptysis) however in the biopsy crescents are observed in all glomeruli as seen in kidney biopsy (Fig.1 and Fig.2) Therefore, the patient is on intermittent hemodialysis 3 times a week.

Results:

Management with rituximab in anti-GBM, although it is not the first-line treatment, has been found in retrospective studies to help improve patient and kidney survival by making antibodies negative for up to 25 months. In a case report in which the biopsy reported 100% crescentic glomerulonephritis without chronic damage in a patient that required hemodialysis, treatment with Rituximab 1 g replacing cyclophosphamide resulted in recovery of renal function without dependence on RRT. Of the patients who have been treated with Rituximab worldwide, the vast majority have presented remission of the disease. Although our patients did not present remission of the disease, the antibodies were negative, and the symptoms improved. Although there is not enough data to support Rituximab as a first-line agent, as a treatment for anti-GBM, in cases where it is possible to give it to patients due to lack of other treatments, they have shown significant improvement. 

Conclusions:

Management of young patients with anti-MBG with rapidly progressive glomerulonephritis should be focuses in detain the progression of kidney damage, preventing the chronic requirement of renal replacement therapy, and stop alveolar hemorrhage. Since rituximab have shown beneficial effects in patients with anti-MBG, should be studied as a treatment for this patient.  

I have no potential conflict of interest to disclose.

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