Spectrum of Primary Glomerular Diseases in Patients Presenting with Urinary Abnormalities *

Introduction: Primary Glomerular Diseases are a spectrum of renal disorders of unknown aetiology with distinct characteristics, specific natural history and prognosis. A thorough evaluation is pre-requisite to establish the diagnosis since many systemic diseases and secondary aetiology masquerade as primary diseases. Methods: This prospective observational study was conducted at a tertiary care centre and included 30 patients, with clinical features suggestive of primary glomerular diseases, of which 23 patients (76.6%) were males and 07 patients (23.33%) were females. The mean age at presentation was 37.23 ± 12.89 years. Among the observed spectrum of Primary Glomerular Diseases, IgA Nephropathy (IgA N) was seen in 26.67% patients, Focal Segmental Glo-merulosclerosis (FSGS) in 20% patients and Membranous Glomerulopathy (MGN) in 13.33% patients, whereas the incidence of other abnormalities had less percentage contribution. Proteinuria was the commonest presentation seen in 60% patients, followed by Microscopic Haematuria in 20%. Mean Serum Creatinine was 0.99 ± 0.16 mg/dl. Mean Serum Albumin was 2.51 ± 0.76 gm/dl. Overall Nephrotic range proteinuria was observed in 15 (50%) patients. Results: IgA N, FSGS & MGN were the commonest observed Primary Glomerular Diseases. Proteinuria, Haematuria, Anasarca and Pedal Oedema were the commonest observed clinical presentations. Conclusions: In this studied series IgA Nephropathy, FSGS and MGN were the most prevelant diagnoses in the patients presenting with Urinary Abnormality. Nephrotic range Protenuria was the major indication for biopsy, there is a temporal variation in glomerulopathies wherein there is increase in incidence of IgA Nephropa-thy and decrease in incidence of FSGS.


Introduction
The underlying cause of many glomerular diseases remains unknown, which are classified as Primary Glomerular Diseases, wherein the disease involves kidneys primarily and then there are Secondary Glomerular Diseases where the kidneys get involved secondary to some systemic disorders.
When a patient presents with suspicion of some glomerular disease, all measures must be taken to look for an underlying systemic disease. Evaluation includes assessment for proteinuria, gross/microscopic haematuria and hypertension. Determining the exact underlying aetiology, prognosis and alter the disease progression and severity by timely intervention, if possible. The variable manifestations among glomerular diseases mandate a kidney biopsy for establishing a diagnosis. Urinary abnormality on urinalysis is a common finding in clinical practice. Evaluation of such abnormalities by a renal biopsy helps in identifying an underlying glomerular disease in time.
Data from the western literature depicts IgA Nephropathy (IgA N) as the most common GN in white adults in many studies [1] [2]. Earlier many studies showed Membranous Nephropathy (MGN) as a common cause for adult nephrotic syndrome in US and Europe. However recent studies have shown that frequency of Focal Segmental Glomerulosclerosis (FSGS) is increasing and has become the most common Primary Glomerulopathy in blacks and the Hispanic population [3].
Since most of the data in this respect is from the western literature, this study was carried out to evaluate and identify the pattern and distribution of various Primary Glomerular diseases in Indian adult population, Indians have a relatively heterogenous ethnicity and in addition the rapid urbanization is expected to further result in changing pattern of glomerular disease, which further emphasizes the reason to observe and study the new paradigm.

Materials & Methods
This study was performed at a tertiary care hospital and was approved by the Internal Ethical Committee of the hospital vide No. 01/07/MAY/CHWC/2022. A written informed consent was taken from all the patients who were enrolled in this study and also before they were subjected to renal biopsy. A group of 30 patients were included in the study. This study was conducted between Jan 2021 and Dec 2021 (total duration 12 months).

Inclusion & Exclusion Criteria
All adult patients (age > 18 years) presenting at the outpatient department with Asymptomatic Urinary Abnormalities (proteinuria, gross/microscopic haematuria, with or without hypertension) were included in the study. Subjects having azotaemia/features of uraemia, previous history of known renal dysfunction or any urinary abnormality were excluded from the study. All patients who were > 60 years age, critically ill, had diagnosed glomerular diseases, hypertension, di-Open Journal of Nephrology abetes mellitus, chronic liver disease, HIV infection or any other underlying condition that could lead to secondary glomerular disease were also excluded from the study.

Study Design & Sample Size
It was a prospective observational study conducted at a tertiary care centre in North-Western India. A sample size of 30 patients was considered based on the prevalence of primary glomerular diseases in patients with no previously known urinary abnormality, renal dysfunction or any glomerular disease.

Methodology
A group of 30 patients detected to have renal dysfunction in the form of proteinuria, gross/microscopic haematuria, active urinary sediments with or without hypertension during evaluation at the outpatient department of a tertiary care hospital were included in the study. Detailed history was taken regarding presenting complaints, presence of any renal specific complaints or past history of any underlying renal disorders, or other comorbidities that can lead to secondary renal dysfunction, and if found positive such patients were excluded from the study. Baseline blood pressure was measured for all the subjects. A battery of investigations was then done that included baseline serum creatinine (in mg/dl), 24 hours urine protein (in grams), qualitative urine albumin by dipstick method (graded readings: negative, trace, 1+ to 4+), urine routine and microscopic analysis, serum albumin (in gm/dl) and ultrasonography of abdomen. Following this, the study patients were subjected to Percutaneous Renal Biopsy with an 18 Gauge Automated Renal Biopsy Gun after a written informed consent. A written informed consent was pre-requisite for every patient in a predesigned format in the language that patient best understood before inclusion in the study group. This study was approved by the Internal Ethical Committee of the hospital vide No. 01/07/MAY/CHWC/2022.

Analysis of Data
The data was documented on a pre-designed format, tabulated and was analysed using SPSS (Statistical Packages for Social Sciences) for Windows Version 20.0.
The qualitative data variables were expressed using frequency and percentage (%), whereas the quantitative data variables were expressed using mean & SD in nearest two decimal figures.

Discussion
Primary glomerular disease in patients with asymptomatic urinary abnormalities were found to be more common in males (76.67%) than females (23.33%). However, females presented at an earlier age as compared to males. The three most common Primary Glomerular Disorders observed were IgA Nephropathy  [4]. However, MCD comprised only 10.2% of the total biopsies in a study in Nepal [5], MCD shows a variable geographic distribution and is more common in Asia than in North America or Europe [6] In Korea [7] and Thailand [8], MCD amounted to 26.6% and 45.8% of all primary glomerular diseases, respectively, FSGS was observed to be the most common Primary Glomerulo-nephropathy in Brazil [9], India [10], Bahrain [11], Croatia [12] and Sudan [13], 34.5% in Czech Republic [14], whereas 18.8% in Italy [15]. However, MCD was the most common biopsy proven Primary glomerular disease with wide age of presentation in a study by Shalini Bhalla et al in Uttar Pradesh in India [16].

Limitations
It being an observational study, the tendency towards bias and confounding inherent to this study model owing to the lack of randomization and process of selection of subjects cannot be ruled out despite best of efforts. This may have effect on the observations and thus during interpretation of outcome this factor needs to be considered to so as to appreciate the results in a more realistic fashion.

Conclusion
This study was unique in the form that it studied the distribution of only the primary glomerular diseases in individuals presenting with asymptomatic uri- This study was one of its kind and elaborates upon not only the observed spectrum of primary glomerular diseases in individuals with asymptomatic urinary abnormality, but also provides an insight about their complete clinical profile with distribution individually in both males and females.

Conflicts of Interest
There has been no interest whatsoever of any third party or firm pertaining to