Membranous nephropathy is characterized by deposition of immune complexes in the epithelial side of glomerular capillary loop. It often occurs to patients that are above their 40s and there are more male patients than female patients. Most patients have typical symptoms of nephrotic syndrome---swelling, proteinuria, hypoalbuminemia, hyperlipidemia. Some patients can only have proteinuria.
Proteinuria. Daily protein leakage in membranous nephropathy patients has great fluctuation and this may be related with their protein intake, body posture and activity level.
Membranous nephropathy is usually dormant and some patients find that they have proteinuria in physical examinations. If the onset is sudden especially in case of renal tubular dysfunction, it is necessary to check weather there is any infections, renal toxicity drugs or toxins.
The severity and duration of proteinuria is closely related to the prognosis of membranous nephropathy. Patients with massive proteinuria should limit daily protein intake within 0.8g/kg and at the same time have adequate calory supply.
Hematuria. About half membranous nephropathy patients will have microscopic hematuria. However it is not typical sign of MN, therefore it is important to find out the primary causes.
High blood pressure. 17%-50% adult patients will have high blood pressure at the onset of the disease. If patients have hypertension or renal dysfunction, the prognosis is poor.
The ideal blood pressure for membranous nephropathy patients should be below 125/70. The first drug choice for high blood pressure are ACEI and ARB. Low-salt diets can help relieve water and sodium retention and control high blood pressure.
Venous thrombus. Membranous nephropathy patients have 40% higher incidence to develop venous thrombus than other glomerular diseases especially if patients have persistent nephrotic syndrome symptoms. Anti-coagulation is therefore very important.
If symptoms can not be relieved with the above drugs and measures and if illness conditions become even worse, immunosuppressive agents are needed to suppress the patient’s immunity so as to help reduce proteinuria, control complications, slow down worsening of kidney functions.