Clinicopathological Spectrum of Nephrotic Syndrome in Adults: A Study of 50 cases from Chennai

INTRODUCTION: Nephrotic syndrome is a clinical syndrome with a characteristic pentad. They are: (1) proteinuria : adult > 3.5g/day; child >40mg / hour per m2, (2) hypoalbuminemia <3.5 g/dl, (3) edema, (4) hypercholesterolemia (5) lipiduria. Nephrotic syndrome is pathognomonic of glomerular disease. Patients may be nephrotic with preserved renal function, but in many circumstances, progressive renal failure will become superimposed when nephrotic syndrome is prolonged. Independent of the risk of progressive renal failure, the nephrotic syndrome has far reaching metabolic effects that can influence the general health of the patient. Fortunately some episodes of nephrotic syndrome are self limiting and a few respond completely to specific treatment. However, for most patients, it is a chronic condition. Not all patients with proteinuria will have all components of nephrotic syndrome; some have a normal serum albumin and no edema. This difference presumably reflects the varied response of protein metabolism. Some patients sustain an increase in albumin synthesis in response to heavy proteinuria that may even normalise serum albumin. There are several causes of nephrotic syndrome and causes of nephrotic syndrome in adults are different from that of childhood. Minimal change disease is the major cause of nephrotic syndrome in childhood, whereas in adults the main causes are membranous glomerulonephritis, focal segmental glomerulonephritis, minimal change disease, diabetic nephropathy, IgA nephropathy and connective tissue disorders. Etiology, clinical pattern, laboratory features vary from one type to another, as also the treatment options and prognosis. AIMS AND OBJECTIVES: 1. To study the varied clinical presentation of nephrotic syndrome in adults. 2. To evaluate in detail the biochemical and other laboratory abnormalities in adult patients with nephrotic syndrome. 3. To find out the etiological profile of nephrotic syndrome in adults in our study population. 4. To compare the etiological profile of nephrotic syndrome in our study population with other similar studies, and to assess whether there is change in etiologic pattern in adult nephrotic syndrome in our institution. MATERIALS AND METHODS: Place : Department of Medicine and Department of Nephrology, Government Stanley Hospital. Design : Observational Study. Period : October 2007 to October 2009. Sample size : 50 patients. Inclusion Criteria: 1. Age >18 years of age. 2. Newly admitted patients with clinical and laboratory findings suggestive of nephrotic syndrome. Exclusion Criteria: 1. Nephrotic syndrome in children and adolescents. 2. Known patients with nephrotic syndrome admitted with relapses and complications. 3. Patients with diabetic nephropathy, who do not require biopsy. 4. Other causes of volume overload like cardiac and hepatic causes, renal causes other than nephrotic syndrome, malnutrition, etc. METHODS: Detailed history was taken from all patients admitted with features suggestive of nephrotic syndrome. This included presenting complaints and history of presenting illness, significant past medical history and history suggestive of complications of nephrotic syndrome. The patients were then examined thoroughly and biochemical investigations were carried out to establish the diagnosis of nephrotic syndrome. Also, investigations to establish the etiology of nephrotic syndrome were done. After obtaining patients’ consent, renal biopsy was done to find out the etiology and to decide on the therapy. The patients were treated accordingly and were advised to get reviewed periodically. All relevant data, clinical, laboratory and biopsy details were recorded and were analysed at the end of the study. The proforma used for the same is attached. Ethical Committee approval was obtained. OBSERVATIONS AND DATA ANALYSIS: Total number of patients – 50. Male – 22, Female – 28. Age group range – 19 to 53 years. Mean age – 31 years. The most common clinical features observed in our study were pedal edema (84%), facial puffiness (94%), abdominal distension (40%). A combination of pedal edema and facial puffiness occurred in 38% of cases, a combination of pedal edema, facial puffiness and abdominal distension occurred in 40% of cases, facial puffiness done in 16% cases and pedal edema alone in 6% cases. Duration of onset of illness to the time of presentation to the hospital ranged from 1 week to 20 weeks. Mean duration of presenting complaints was 6 weeks. SUMMARY AND CONCLUSIONS: 1. 50 adult patients with nephrotic syndrome participated in the study. Males constituted 44% and females 56% of cases. 2. The commonest presenting complaint was facial puffiness, which occurred in 94% of cases. Pedal edema occurred in 84% and abdominal distension on 40% of cases. 3. Systemic hypertension was present in 38% of cases. Males constituted 24% of cases and females 14%. Systemic hypertension was present in 50% of cases with histological subtypes, MGN and MPGN and less common in other subtypes. 4. 24 hours urine protein excretion ranged from 3 g to 15 g/ day. The mean value was 6.64 g/day. Proteinuria was severe with histopathological subtype, minimal change disease (mean -9.22 g/day). 5. Hypercholesterolemia was present in 90% of cases. The mean value was 251.2 mg%. 6. Renal failure was present in 14% of cases. Renal failure was present in 27% of cases with FSGS, 25% of MPGN patients and 37% of lupus patients. 7. The commonest histopathological subtype was membranous nephropathy. It occurred in 32% of cases. FSGS was the etiology in 22% of cases, MCD and MPGN in 8% of cases, IgA nephropathy in 16% of cases and lupus nephritis in 14% of cases. 8. In our study, females dominated in all histologic subtypes except in MPGN, where males dominated and in MGN, where both males and females were affected in equal numbers. 9. In patients with FSGS, hypertension was present in 4 cases (36.4%) and renal insufficiency in 3 cases (27.3%). 10. All patients with IgA nephropathy had hematuria on urinalysis. 11. Nephrotic syndrome was primary or idiopathic in 86% of cases and secondary in 14% of cases. Lupus nephritis was the primary etiology in all these cases. 12. All patients with lupus in our study were females. Among these patients with lupus nephritis, one patient had focal nephritis, 4 patients had diffuse proliferative glomerulonephritis (DPGN) and 2 patients had membranous nephritis.