Renal Vein Thrombosis Suggestive of Extramembranous Glomerulonephritis Associated with Sjögren’s Syndrome (Case Report)

Introduction: Glomerular damage during Gougerot-Sjögren syndrome is much rarer than interstitial damage, and is essentially extra-membranous and membrano-proliferative glomerulonephritis. Observation: We report the case of a 44-year-old woman with primary Sjögren’s syndrome, confirmed by clinical dryness syndrome, positive anti-SSA and anti-SSB antibodies, and a salivary gland biopsy revealing grade 4 lymphocytic sialadenitis according to CHISHOLM’s classification. Later, the patient developed nephrotic syndrome, along with hypertension. Renal function remained normal with a creatinine level of 9.3 mg/l, and hematuria was absent. Only antinuclear antibodies tested positive, while anti-PLA2R antibodies were negative. A renal biopsy was performed, which was complicated on the same day by hemodynamic instability with hematuria. Renal CT scan with contrast injection revealed a posterior perirenal hematoma without contrast extravasation. Additionally, bilateral renal vein thrombosis was incidentally discovered, suggesting extramembranous glomerulonephritis. The patient’s hemodynamic status stabilized after fluid resuscitation with isotonic saline solution (0.9%), without the need for blood transfusion. Renal biopsy confirmed extramembranous glomerulonephritis with interstitial fibrosis and minimal tubular atrophy. The initial etiological assessment was negative. The patient was started on oral corticosteroids, angiotensin-converting enzyme inhibitors, and therapeutic anticoagulation for renal vein thrombosis. The patient’s condition improved, with the disappearance of the syndrome and spontaneous regression of the hematoma. Discussion: The association of nephrotic syndrome and renal vein thrombosis primarily suggests glomerulopathy, in particular extra-membranous glomerulonephritis. Sjögren’s syndrome can be associated with extra-membranous glomerulonephritis without being its direct cause. Like, it is possible that it is a cause of glomerulonephritis, essentially extra membranous and membrano-proliferative. Conclusion: Sjögren’s syndrome is generally underestimated cause of glomerulonephritis, which should be considered in cases of extra-membranous glomerulonephritis.