Nephrotic syndrome

Nephrotic syndrome (NS) = heavy proteinuria with hypoalbuminemia and edema. Dental relevance is driven by two major complications, and both differ by AGE GROUP: (1) THROMBOEMBOLISM — NS is a hypercoagulable state (urinary loss of antithrombin III/protein S, raised fibrinogen/factor VIII). In ADULTS venous/arterial thromboembolism risk is substantial, highest with membranous nephropathy, serum albumin <25 g/L and proteinuria >10 g/day, and mostly within the first ~6 months; many adults take antiplatelet/anticoagulant prophylaxis. In CHILDREN the overall rate is lower but real — greatest in adolescents, during relapse, and with central lines — and cerebral venous sinus thrombosis is a characteristic pediatric event. (2) INFECTION — urinary loss of complement factor B/properdin, immunoglobulins and opsonins plus functional hyposplenism and immunosuppressive therapy increase susceptibility to encapsulated organisms (esp. Streptococcus pneumoniae); in CHILDREN spontaneous bacterial peritonitis, sepsis and cellulitis during relapse dominate, and pneumococcal/Hib/varicella/influenza vaccination is advised. STEROIDS differ too: children with steroid-sensitive NS cycle high-dose prednisolone, whereas adults more often receive steroid-sparing agents (calcineurin inhibitors, rituximab, cyclophosphamide, MMF); steroids can mask infection signs in both. NSAIDs are high-risk in both groups (AKI plus NSAID-associated nephrotic lesions) and hypoalbuminemia alters protein-bound drug handling.