Cyclosporine therapy could be considered for membranoproliferative glomerulonephritis with immunoglobulin A deposits: a case report

Background

Membranoproliferative glomerulonephritis (MPGN), a rare glomerulonephritis that causes nephrotic syndrome in children, is often difficult to treat. Typical immunofluorescence findings include strong C3 staining in a granular pattern along the glomerular capillary wall and negative IgA staining. IgA-dominant MPGN without hypocomplementemia has been reported. Herein, we report a rare case of MPGN with hypocomplementemia and predominant IgA subclass 2 deposits.

Case presentation

An 11-year-old girl showed proteinuria on a school urinalysis screening and presented with upper eyelid edema. The urinalysis showed elevated urinary protein levels and hematuria. Laboratory examinations revealed the following: serum albumin, 1.3 g/dL; serum creatinine, 0.54 mg/dL; and C3c, 67 mg/dL (normal range: 73–138 mg/dL). The physical and laboratory findings did not suggest autoimmune diseases. A renal biopsy was then performed. Specimen examination under a light microscope showed mesangial cell proliferation, increased mesangial matrix with lobulation, and some double contours of the glomerular basement membrane in almost all glomeruli, which are characteristic findings of MPGN. Immunofluorescent studies showed IgA deposits not only in the mesangial regions but also along the capillary walls, which were more strongly stained than C3. IgA subclass staining showed a stronger immunoreactivity for IgA2 than IgA1. Electron microscopic studies showed electron-dense deposits in the subendothelial, subepithelial, and paramesangial regions. Based on these findings, the patient was diagnosed with IgA-dominant MPGN. Accordingly, she was treated with three courses of methylprednisolone pulse therapy (MPT), followed by prednisolone, mizoribine, and lisinopril. Although hypocomplementemia improved after three courses of MPT, nephrotic-range proteinuria and hypoalbuminemia remained; therefore, two courses of MPT were additionally administered, and the immunosuppressant was changed from mizoribine to cyclosporine (CsA). Finally, the urinary protein level decreased, and a subsequent renal biopsy, two years later, showed improvement in the lesions.

Conclusions

We report an atypical case of MPGN with IgA2 dominant deposits along the glomerular capillary wall and in the mesangial region. The case was refractory to standard therapy but sensitive to CsA, which resulted in remission. Our findings suggest that CsA may be useful as an immunosuppressant to treat refractory MPGN.

Membranoproliferative glomerulonephritis in Russian population

AIM

Analysis of etiology, clinical and morphological manifestations, approaches to therapy and prognosis of membranoproliferative glomerulonephritis (MPGN).

MATERIALS AND METHODS

Cases of MPGN were retrospectively identified in the period 2000-2017 with subsequent analysis of etiology, clinical data and morphology (including deposits of immunoglobulins (Ig) and C3 complement fractions). The achievement of complete and partial remissions (PR, CR), overall survival, progression (by composite endpoint: decrease in the estimated GFR (eGFR) ≥50% from the baseline or eGFR <15 ml/min/1.73 m2 or the onset of dialysis).

RESULTS

214 cases of MPGN entered the study with the average age of 44±16 years. Most patients had nephrotic syndrome and significant hematuria. In 58.4% of cases, eGFR was <60 mL/min/1.73 m2, and every fifth patient had CKD 4 or 5 stages. The prevalence of MPGN among all biopsy-confirmed glomerulopathies was 9.3%. Idiopathic MPGN (iMPGN) was detected in 30.4% of cases, secondary MSGN (sMPGN) - in 69.6% (autoimmune diseases - 34.1%, infectious diseases - 16.4%, monoclonal gammopathies - 9.3%, complement-mediated damage - 9.8%). Ig+C3+MPGN was mainly associated with autoimmune diseases and infections; C3-glomerulopathy or thrombotic microangiopathy were most often causes of Ig-C3+MPGN; Ig-C3-/Ig+C3-MPGN had heterogeneous etiology. The median follow-up period was 28 [7; 37] months. The 10-year total cumulative patient and renal survival rates were 71 and 50%, respectively (without differences between sMPGN and iMPGN). The frequency of the PR/CR was 50% (iMPGN - 46.2%, sMPGN - 51.3%) depending on the etiology of the MPGN (p=0.049). The cumulative 10-year progression-free renal survival was nearly 100% in cases with PR/CR and 0% in non-responders.

CONCLUSION

MPGN is a severe variant of glomerular damage with a heterogeneous etiological structure and an unfavorable prognosis. Targeted clinical and morphological diagnostics of MPGN allows to identify the cause of the disease in most cases. This approach is reliable for the adequate treatment choice and improvement of outcomes in MPGN.

IgA-dominant glomerulonephritis with a membranoproliferative pattern of injury

Immunoglobulin A (IgA)-dominant membranoproliferative glomerulonephritis (MPGN) is a descriptive term for renal biopsies in which differential diagnoses of unusual IgA nephropathy (IgAN), infection-related GN, or other etiologies are considered. We sought to understand clinical and pathologic features of this finding. Native kidney biopsies with IgA-dominant immune deposits and diffuse MPGN features without significant exudative features or subepithelial deposits were retrospectively reviewed. Two groups (n = 27, 33 biopsies) were identified: patients with chronic liver disease and those without. Patients without chronic liver disease (n = 15) were men (73%, age 40) who presented with nephrotic-range proteinuria, hematuria, renal insufficiency, negative serologic studies, and no history of infection. At a median interval of 3 years, 11 had available follow-up information. Three (27%) progressed to end-stage renal disease. One had recurrent IgA-dominant GN in the renal allograft less than 1 year posttransplant. Four of 5 patients with repeat biopsies had persistent IgA-dominant MPGN. Patients with chronic liver disease (n = 12) had similar biopsy findings, but 42% had concurrent infections, some occult. At a median interval of 7 weeks, 8 patients (80% of those with follow-up) had died and 2 were dialysis dependent. In conclusion, IgA-dominant MPGN was seen in 2 clinical cohorts in this study. In patients without chronic liver disease, this appears to represent either a unique clinicopathologic entity with a poorer prognosis than IgAN or an aggressive variant of IgAN. Patients with chronic liver disease often have underlying infection, and regardless of treatment, die within 1 year because of complex medical conditions.

Immunoglobulin A dominant membranoproliferative glomerulonephritis in an elderly man: A case report and review of the literature

Immunoglobulin A (IgA) dominant membranoproliferative glomerulonephritis (MPGN) is rare, described only as case reports. We report a rare case of an elderly man presenting with rapidly progressive renal failure and nephrotic range proteinuria with histological, immunofluorescence, and ultrastructural findings supporting a diagnosis of IgA dominant MPGN. Autoimmune disease, cryoglobulinemia and infection-associated glomerulonephritis were excluded. Remission was achieved within 3 months of treatment. This case highlights an uncommon diagnosis with a good response to therapy. The differential diagnosis of IgA nephropathy with MPGN-like pattern is discussed.