Abstract

Background: Lupus Nephritis (LN) is one of the more common and serious manifestations of Systemic Lupus Erythematosus (SLE). It is regarded as both a strong predictor and a leading cause for morbidity and mortality amongst those who suffer from the disease.

Objectives:  To observe the variable histopathological patterns of lupus nephritis by renal biopsy and to observe whether American College of Rheumatology (ACR) guidelines are being followed during treating   the LN patients or not.

Patients and Methods: The charts of 30 consecutive patients with biopsy proven lupus nephritis admitted into Dhaka Medical College Hospital from January 2014 to June 2014 were studied. Patient with SLE without evidence of LN (defined by proteinuria more than 0.5 gm/24 hours and/or haematuria, cellular casts) were excluded.

Result: The mean age of was 26.63 ± 9.73 SD years and  male:female ratio was  0.15.There  were  ANA positive  100% , Anti-ds DNA positive  83.3% and all the patients (100%) had low complement (C3 and C4) level.Percutaneous renal biopsy  showed  predominant  types of  lupus nephritis was Class IV  (33.3%),  then  Class III  (26.7%).  Mean Activity Index (AI) 7.83 ± 2.52 and Chronicity Index (CI) 1.4 ± 1.9. In management of 76.67% received intravenous pulse methylprednisolone, 63.3%   received intravenous pulse high-dose cyclophosphamide and 16.67% received Mycophenolate Mofetil (MMF).

Conclusions:  In spite of MMF’s more safety profile, Cyclophosphamide was generally used as a first line agent in this study for financial constance. Though the induction regimen of Cyclophosphamide used in DMCH was similar to ACR guideline, but the maintenance regimen was not followed by ACR guideline which was consistent with the KDIGO (Kidney Disease Improving Global Outcomes) guideline. But the regimen of MMF and glucocorticoids used in management of LN patients was similar to ACR guideline, 2012.

Keywords: Histopathologist; Lupus Nephritis; Implication; Bangladesh

Introduction

Systemic Lupus Erythematosus (SLE) is considered to be a prototypic autoimmune disease, characterized by involvement of multiple organs including joints, skin, central nervous system, lungs, kidneys, gastrointestinal tracts, cardiovascular system and bone marrow, accompanied by multiple laboratory abnormalities and frequent exacerbation [1]. The overall incidence rates of SLE ranges from approximately 1.8 to 7.6 per 100,000 persons/year and prevalence rates generally range from 20-70 per 100,000 [2]. The histopathology of Lupus Nephritis (LN) is extremely pleomorphic. The introduction of renal biopsy in the 1950s, the application of immunoflurescence and electron microscopic techniques in the 1960s and increasing knowledge about mechanisms of immune – mediated glomerular injury derived from experimental studies on serum sickness and other models formed the basis of the recognition and classification of the various patterns of renal injury in SLE [3,4]. As early as 1964, focal segmental glomerulonephritis, diffuse proliferative glomerulonephritis and membranous glomerulopathy were recognised as seperate entities, followed by the identification of mesangial lesions in the 1970s. Survival of patients with SLE has improved remarkably over past decades. Earlier diagnosis, awareness of the vascular risk factors such as hypertension, nephritic syndrome, antiphospholipid syndrome and better approaches to treatment have undoubtly contributed to the improved prognosis of SLE [5]. The first World Health Organization (WHO) classification was formulated by Pirani and Pollak in Buffalo, New York in 1974 and was first used in publications in 1975 and 1978 (Table 1) [4,6]. The classification addressed glomerular lesions only. Class-I was applied to renal biopsies showing no detectable glomerular abnormalities by light, flurescence or electron microscopy. Class-II was defined as purely mesangial immune deposition and was subdivided into two subclasses depending on whether mesangial hypercellularity was present. Class-III lesions were defined as proliferative glomerulonephritis affecting fewer than 50% of the glomeruli (i.e., focal), whereas class-IV was defined as proliferative glomerulonephritis affecting more than 50% of the glomeruli (i.e., diffuse). The diagnosis of SLE is often clinically established by the presence of certain clinical and laboratory features defined by the 1997 modified American Rheumatism Association (ARA) criteria. Development of 4 out of 11 criteria over a lifetime gives a 96% sensitivity and specificity for SLE [7]. Kidney is a major target organ in upto 60% of patients with SLE, with 25-50% presenting with kidney involvement already at the time of lupus diagnosis [8]. Lupus Nephritis (LN) is regarded as both a strong predictor and a leading cause for morbidity and mortality amongst those who suffer from the disease. The presentation of LN is highly variable, ranging from mild asymptomatic proteinuria to rapidly progressive glomerulonephritis with haematuria and red cell casts. Generally renal involvement tends to occur within the first 2 years of SLE with its frequency decreasing significantly after the first 5 years of disease [7,8]. Several studies have illustrated the lack of reliability of diagnoses rendered on the basis of clinical features alone. Therefore, making a diagnosis on clinical grounds alone is problematic and risky, underscoring the need for renal biopsy to see the histopathological pattern and to guide therapeutic decision. As the therapeutic armamentarium for LN expands, it becomes even more imperative that the correct diagnosis be made prior to instituting therapy [3,8]. Making a diagnosis of SLE is usually not a challenging problem. In addition to clinical criteria, several serological tests for SLE, including the anti-nuclear antibody and anti-double-stranded DNA antibody assays, antibodies to anti-Sm, anti-Ro and anti-La, as well as complement assays are available as confirmatory tests. However, once a diagnosis of SLE has been made, staging the renal involvement and judging the degree of activity requires the use of a histological classification. The World Health Organization (WHO) classification and more recently the International Society of Nephrology/ Renal Pathology Society (ISN/ RPS) classification, have captured this histological heterogenicity and are widely utilized in managing patients. The main purpose of classifying lupus nephritis is to make sure that the type of treatment recommended matches the severity of disease and that information about short and long-term prognosis guides both the duration and intensity of treatment. Treatment strategies will differ based on biopsy findings [3,9].

Introduction

Systemic Lupus Erythematosus (SLE) is considered to be a prototypic autoimmune disease, characterized by involvement of multiple organs including joints, skin, central nervous system, lungs, kidneys, gastrointestinal tracts, cardiovascular system and bone marrow, accompanied by multiple laboratory abnormalities and frequent exacerbation [1]. The overall incidence rates of SLE ranges from approximately 1.8 to 7.6 per 100,000 persons/year and prevalence rates generally range from 20-70 per 100,000 [2]. The histopathology of Lupus Nephritis (LN) is extremely pleomorphic. The introduction of renal biopsy in the 1950s, the application of immunoflurescence and electron microscopic techniques in the 1960s and increasing knowledge about mechanisms of immune – mediated glomerular injury derived from experimental studies on serum sickness and other models formed the basis of the recognition and classification of the various patterns of renal injury in SLE [3,4]. As early as 1964, focal segmental glomerulonephritis, diffuse proliferative glomerulonephritis and membranous glomerulopathy were recognised as seperate entities, followed by the identification of mesangial lesions in the 1970s. Survival of patients with SLE has improved remarkably over past decades. Earlier diagnosis, awareness of the vascular risk factors such as hypertension, nephritic syndrome, antiphospholipid syndrome and better approaches to treatment have undoubtly contributed to the improved prognosis of SLE [5]. The first World Health Organization (WHO) classification was formulated by Pirani and Pollak in Buffalo, New York in 1974 and was first used in publications in 1975 and 1978 (Table 1) [4,6]. The classification addressed glomerular lesions only. Class-I was applied to renal biopsies showing no detectable glomerular abnormalities by light, flurescence or electron microscopy. Class-II was defined as purely mesangial immune deposition and was subdivided into two subclasses depending on whether mesangial hypercellularity was present. Class-III lesions were defined as proliferative glomerulonephritis affecting fewer than 50% of the glomeruli (i.e., focal), whereas class-IV was defined as proliferative glomerulonephritis affecting more than 50% of the glomeruli (i.e., diffuse). The diagnosis of SLE is often clinically established by the presence of certain clinical and laboratory features defined by the 1997 modified American Rheumatism Association (ARA) criteria. Development of 4 out of 11 criteria over a lifetime gives a 96% sensitivity and specificity for SLE [7]. Kidney is a major target organ in upto 60% of patients with SLE, with 25-50% presenting with kidney involvement already at the time of lupus diagnosis [8]. Lupus Nephritis (LN) is regarded as both a strong predictor and a leading cause for morbidity and mortality amongst those who suffer from the disease. The presentation of LN is highly variable, ranging from mild asymptomatic proteinuria to rapidly progressive glomerulonephritis with haematuria and red cell casts. Generally renal involvement tends to occur within the first 2 years of SLE with its frequency decreasing significantly after the first 5 years of disease [7,8]. Several studies have illustrated the lack of reliability of diagnoses rendered on the basis of clinical features alone. Therefore, making a diagnosis on clinical grounds alone is problematic and risky, underscoring the need for renal biopsy to see the histopathological pattern and to guide therapeutic decision. As the therapeutic armamentarium for LN expands, it becomes even more imperative that the correct diagnosis be made prior to instituting therapy [3,8]. Making a diagnosis of SLE is usually not a challenging problem. In addition to clinical criteria, several serological tests for SLE, including the anti-nuclear antibody and anti-double-stranded DNA antibody assays, antibodies to anti-Sm, anti-Ro and anti-La, as well as complement assays are available as confirmatory tests. However, once a diagnosis of SLE has been made, staging the renal involvement and judging the degree of activity requires the use of a histological classification. The World Health Organization (WHO) classification and more recently the International Society of Nephrology/ Renal Pathology Society (ISN/ RPS) classification, have captured this histological heterogenicity and are widely utilized in managing patients. The main purpose of classifying lupus nephritis is to make sure that the type of treatment recommended matches the severity of disease and that information about short and long-term prognosis guides both the duration and intensity of treatment. Treatment strategies will differ based on biopsy findings [3,9].

Methodology

Type of Study

It was a Cross- Sectional Observational Study. 

Place of Study

Department of Medicine and Department of  Nephrology, Dhaka Medical College Hospital, Dhaka, Bangladesh.

Period of Study

From January 2014 to June 2014.

Study Population

30 cases, who were diagnosed clinically as Lupus Nephritis on the basis of ACR criteria, irrespective of age and sex were studied with subsequent renal biopsy and histopathology.

Inclusion Criteria

1. SLE patients (fulfilled at least four out of eleven ACR revised classification criteria for SLE) having proteinuria ( >0.5 gm/day or 3+), haematuria or cellular casts (red cell, granular or tubular)
2. Lupus Nephritis patients age >12 years and who had no contraindication for renal biopsy
3. Lupus Nephritis patients who had no contraindication to steroid or cytotoxics

Exclusion Criteria

1. SLE patients who did not fulfill the ACR criteria of renal involvement
2. Lupus Nephritis patients who had containdication to renal biopsy
3. LN patients contraindicated to steroid or cytotoxics
4. LN patients who did not give consent
5. Pregnant LN patient

Operational Definitions

1. Systemic Lupus Erytheatosus (SLE) : According to American College of Rheumatology(ACR) revised classification criteria, development of 4 out of 11 criteria over a lifetime of a patient will be level as Systemic Lupus Erytheatosus (SLE).
2. Lupus Nephritis (LN) : LN is defined as clinical and laboratory manifestations that meets ACR criteria (persistent proteinuria >0.5 gm/day or greater than 3+ by dipstick and/or cellular casts including red blood cells, haemoglobin, granular, tubular or mixed). A review of the ACR criteria has recommended that a spot urine protein/ creatinine ratio of >0.5 can be substituted for the 24- hour protein measurement and active urinary sediment (>5 RBCs/hpf, >5 WBCs/hpf in the absence of infection or cellular casts limited to RBC or WBC casts) can be substituted for cellular casts

Operational Definitions

1. Systemic Lupus Erytheatosus (SLE) : According to American College of Rheumatology(ACR) revised classification criteria, development of 4 out of 11 criteria over a lifetime of a patient will be level as Systemic Lupus Erytheatosus (SLE).
2. Lupus Nephritis (LN) : LN is defined as clinical and laboratory manifestations that meets ACR criteria (persistent proteinuria >0.5 gm/day or greater than 3+ by dipstick and/or cellular casts including red blood cells, haemoglobin, granular, tubular or mixed). A review of the ACR criteria has recommended that a spot urine protein/ creatinine ratio of >0.5 can be substituted for the 24- hour protein measurement and active urinary sediment (>5 RBCs/hpf, >5 WBCs/hpf in the absence of infection or cellular casts limited to RBC or WBC casts) can be substituted for cellular casts

Sample Size

Formula,

                n=Z²pq/e².

According this prevalence the sample size was 45, as  time was limited, here 30 cases who were diagnosed clinically as lupus nephritis on the  basis of ACR criteria, with subsequent renal biopsy and histopathology and who fufilled the inclusion and exclusion criteria admitted into Dhaka Medical College Hospital from January 2014 to June 2014 were studied.

Data Collection

After getting admission into DMCH suspected lupus patient was seen by unit doctor, after doing urine analysis if there was proteinuria(>0.5 gm/day or 3+), haematuria or cellular casts present and level as lupus nephritis immediately informed me through cell phone. I was then reevaluate the case, discuss with my co-guide and  collect clinical and laboratory data and was recorded them as suspected lupus nephritis on a structured form on admission. Patient was assessed daily during hospital stay to avoid inter-observer variation. Clinical assessment included recording of presenting symptoms and their duration, pre-biopsy blood pressure, history of diabetes and/or hypertension and laboratory variables included pre-biopsy hematocrit, platelet count, blood urea nitrogen, serum creatinine, albumin, ESR, proteinuria, blood grouping and Rh-typing, HBsAg and Anti-HCV were recorded. Biopsying the kidney was an invasive procedure and associated with several potential risks. Bleeding, the most serious of these complications, sometimes required blood transfusion. Other risks include patient discomfort, infection was managed.

Each subject or gurdian were informed of the aims, methods, anticipated benefits and potential hazards or risks of the study. After that informed written consent was  taken from every subject or gurdian of the patient. In the event of a case less than 18 years,consent was obtained from the eligible gurdians.The patient who were not fit for renal biopsy or who did not give consent, excluded from the study. Then patient  underwent percutaneous renal biopsy under ultrasound guidence by fellow doctor or postgraduate doctor or MD(Nephrology) part-III students at Nephrology department,DMCH and with all aseptic precautions specimen was collected in a container with 10% formalin for light microscopy and was preserved in normal saline for direct immunoflurescence(DIF) microscopy and was sent to department of Pathology of Bangabandhu Sheikh Mujib Medical University(BSMMU), Dhaka. After renal biopsy, each patient was observed for at least 24 hours in the hospital. The histopathology and immunoflurescence reports ware collected and analyzed and then patients were classified by International Society of Nephrology (ISN) / Renal Pathology Society (RPS) Classification of LN,2003 and treated at Nephrology department by respected physicians.

I recorded the basic demographic data such as name, age, gender, occupation,  residence and then recorded the histopathological patterns of lupus nephritis and treatment options which were given by department of Nephrology, DMCH. Then I assessed the compliance with ACR recommendations,2012 with direct supervision of my co-guide and guide.  The outcome of hospital stay was  also recorded as cured, improved or death.

Data Analysis

Data was processed and analysed using computer software Statistical Package for Social Sciences, SPSS 16.0 Chicago-Illionois for windows. The test statistics used were descriptive statistics and Chi-square (x²) and Student’s t-Test. Level of significance was set at 0.05 and p<0.05 was considered statistically significant.

Results

A total of 30 cases of histological proven lupus nephritis were included in the present study. All were analysed and presented in tabulated form.

Population Characteristics: The mean age of the study patient was 26.63 ± 9.733 SD years (range: 12 to 60 years). The age distribution (Table 1) of patients at the time of kidney biopsy were as follows: 30% from 11 to 20 years, 43.3% from 21 to 30 years, 23.3% from 31 to 40 years, 3.3% from 41 to 60 years. There were 4 (13.3%) males and 26 (86.7%) females, with a male: female ratio of 0.15 (Table 2).

Laboratory Abnormalities: Table III shows the laboratory abnormalities of the present study patients. At the time of renal biopsy 18 patients (60%) were anaemic, 19 patients (63.3%) had microscopic haematuria and 7 patients (23.3%) had nephrotic syndrome. Renal function was impaired in 15 patients (50%) with mild renal failure (GFR <90 ml/min) in 8 cases (26.7%), moderate to severe renal impairment (GFR <60 ml/min) in 7 cases (23.3%). Proteinuria greater than 0.5 gm per 24 hours was noticed in all patients and among them 7 patients (23.3%) had nephritic range proteinuria. The other abnormalities leucopenia 3.3%, thrombocytopenia 10%, cellular (RBC) casts in urine 36.7%, raised ESR (>60 mm at the end of first hour) 46.7%.

On serological test, all patients (100%) had a positive ANA, 25 patients (83.3%) had a positive anti-ds DNA, all the patients (100%) had low complement (C3 and C4) level and 8 patients (26.7%) had positive antiphospholipid antibodies.

Histological types and treatment of Lupus Nephritis: Percutaneous renal biopsy was performed in all patients and showed the following results (Table 4): Class I- 1 patient (3.3%), Class I I- 5 patients (16.7%), Class III- 8 patients (26.7%), Class IV- 10 patients (33.3%), Class V- 4 patients (13.3%), Class VI- 2 patients (6.7%). Mean Activity Index (AI) of renal histology were 7.83 ± 2.52 and Chronicity Index (CI) of renal histology were 1.4 ± 1.9 (Table 5).

In management of lupus nephritis 6 patients (20%) were in class I and II and they did not received any Pulse steroids or any immunosuppressives, they received oral steroids, hydroxychloroquine and renoprotective agents like angiotensin converting enzyme inhibitors. Among the study patients, 23 patients (76.67%) received intravenous pulse methylprednisolone daily for 3 days, 19 patients (63.3%) received monthly intravenous high-dose cyclophosphamide, 5 patients (16.67%) received oral mycophenolate mofetil. During maintenance phase 2 patients (6.7%) received oral azathioprine.