Renal manifestations of hepatitis C virus infection

Viral Glomerulopathy

Background

The association between viral infections and glomerular diseases, commonly known as "viral glomerulopathies," has been described in various clinical scenarios for decades. Despite advancements in diagnostic tools, it remains challenging to establish a causative link fully.

Summary

Data from mouse models have substantiated clinical observations and implicate direct viral infection in the pathogenesis of viral glomerulopathy, particularly in human immunodeficiency virus-associated nephropathy. In addition to the traditional concept of direct viral effects on kidneys, other factors such as APOL1 risk alleles can further modify the clinical outcomes or presentations of different viral glomerulopathies. Newly developed antiviral drugs are now applicable to a wider range of patients with lower kidney function and fewer side effects.

Key Message

Efforts focusing on vaccines and antiviral treatments have significantly reduced the incidence of viral glomerulopathies. However, the most recent pandemic caused by severe acute respiratory syndrome coronavirus 2 infection complicated by COVID-associated nephropathy illustrates our susceptibility to novel viruses. Ongoing research is pivotal to deciphering the mechanisms behind viral glomerulopathies and discovering therapeutics in a collaborative approach.

Hepatitis Virus C-associated Nephropathy: A Review and Update

Hepatitis C virus (HCV) infection causes hepatic and extrahepatic organ involvement. Chronic kidney disease (CKD) is a prevalent non-communicable disorder, accounting for significant morbidity and mortality worldwide. Acute kidney injury and CKD are not uncommon sequels of acute or chronic HCV infection.

The pathogenesis of HCV-associated kidney injuries is not well explored. Excess cryoglobulin production occurs in HCV infection. The cryoglobulin may initiate immune complex-mediated vasculitis, inducing vascular thrombosis and inflammation due to cryoglobulin deposits.

Furthermore, direct damage to nephron parts also occurs in HCV patients. Other contributory causes such as hypertension, diabetes, and genetic polymorphism enhance the risk of kidney damage in HCV-infected individuals. Implementing CKD prevention, regular evaluation, and therapy may improve the HCV burden of kidney damage and its related outcomes.

Therefore, in this review, we discuss and update the possible mechanism(s) of kidney injury pathogenesis with HCV infection. We searched for related published articles in EMBASE, Google Scholar, Google, PubMed, and Scopus. We used various texts and phrases, including hepatitis virus and kidney, HCV and CKD, kidney pathology in viral hepatitis, kidney transplantation in HCV-infected patients, kidney allograft survival in viral hepatitis patients, mechanism of kidney pathology in viral hepatitis, dialysis and viral hepatitis, HCV infection and kidney injuries, and viral hepatitis and CKD progression, etc. to identify relevant articles.

Glomerular Disease in Liver Disease

Glomerular diseases are an important cause of kidney disease in patients with liver disease. Although kidney involvement due to tubular or vascular disease is more common, glomerular diseases became more prevalent as hepatitis infections increased and then subsequently decreased with the widespread availability of hepatitis A and B vaccines and the development of effective antiviral treatments for hepatitis B and C. In this review, we discuss the common glomerular pathologies that are seen in patients with liver disease and the current treatment options available to them.

Immunoglobulin-Negative Fibrillary Glomerulonephritis Masked in Diabetic Nephropathy: A Case Report and Discussion of a Diagnostic Pitfall

Introduction

Fibrillary glomerulonephritis (FGN) is a rare glomerular disease with poor prognosis, characterized by deposition of randomly arranged fibrillar material measuring 10-30 nm in diameter. This diagnosis is confirmed with DNAJB9 immunohistochemistry as well as ultrastructural examination. Ultrastructurally, the fibrillary material seen in this entity may be confused with diabetic fibrillosis occurring in diabetic nephropathy.

Case Presentation

We present a case of a 63-year-old African American male with remote hepatitis C virus (HCV) infection and type II diabetes mellitus who presented with chronic kidney disease and nephrotic range proteinuria. A kidney biopsy revealed PAS-positive mesangial matrix expansion consistent with diabetic nephropathy and focal randomly oriented fibril deposition on ultrastructural examination. Immunofluorescence for immunoglobulin G and light chains was negative by both routine and paraffin immunofluorescence. Immunohistochemistry for DNAJB9 was diffusely positive, confirming co-existing FGN.

Discussion/Conclusion

Patients with diabetic nephropathy and FGN have similar clinicopathologic presentations with a slowly progressive onset of kidney failure and proteinuria. In diabetic patients with fibrillary deposits under ultrastructural examination, concurrence of these disease entities must be considered. In this patient with remote HCV infection that was successfully treated years before, it is possible that in the absence of an FGN trigger, there was a loss of antigenicity with a loss of immunoglobulin staining. Therefore, we recommend DNAJB9 immunostaining for patients with remote HCV infection to avoid this diagnostic pitfall. Further studies are needed to determine the potential role of HCV infection in the initiation and etiopathogenesis of FGN.

Spectrum of Kidney Diseases in Patients With Hepatitis C Virus Infection

OBJECTIVES

To study the pathologic spectrum of kidney diseases in patients with hepatitis C virus infection (HCV+).

METHODS

Native kidney biopsy specimens in HCV+ patients were reviewed.

RESULTS

A total of 9,836 native kidney biopsy specimens were evaluated from January 2007 to December 2016, of which 273 (2.8%) were from HCV+ patients, and of these, 115 (42.1%) had diagnoses consistent with HCV-associated glomerulonephritis (GN). Non-HCV-associated kidney diseases comprised most diagnoses (158 cases, 57.9%) including non-immune complex-mediated kidney diseases (127 cases, 46.5%) and other immune complex-mediated glomerular diseases (31 cases, 11.4%). Forty-one (40.6%) patients had HCV-associated GN among 101 HCV+ patients from 2007 to 2011 vs 74 (43.0%) patients with HCV-associated GN among 172 HCV+ patients from 2012 to 2016. HCV-associated GN showed five morphologic patterns: focal proliferative (5.2%), diffuse mesangial proliferative (50.4%), diffuse membranoproliferative (28.7%), proliferative GN with crescentic lesions (7.8%), and membranous patterns (7.8%).

CONCLUSIONS

We found a spectrum of pathologic changes in renal biopsy specimens of HCV+ patients, with most having diseases unrelated to HCV infection, HCV-associated GN showing five morphologic patterns, and availability of effective HCV antiviral therapy not yet resulting in major changes in the spectrum of kidney diseases in these patients.

Treatment of hepatitis C virus infection in patients with mixed cryoglobulinemic syndrome and cryoglobulinemic glomerulonephritis

Cryoglobulinemia is a common extrahepatic manifestation of infection with hepatitis C virus (HCV). When signs and symptoms of systemic vasculitis or glomerulonephritis occur in the presence of circulating cryoglobulins, this syndrome is called "mixed cryoglobulinemia syndrome" (MCS). Historically, interferon-based therapies in HCV have been associated with lower rates of viral cure in patients with MCS than in the general HCV-infected population. The advent of direct-acting antiviral therapies have revolutionized the treatment of HCV, dramatically increasing rates of cure. Early studies of first-generation protease inhibitors (telaprevir and boceprevir) in combination with interferon and ribavirin demonstrated HCV cure rates of 67% and complete clinical response rates of vasculitis symptoms in 60% of patients with MCS; however, regimens were poorly tolerated by patients, 22% discontinued treatment early. More recently, all-oral, interferon-free regimens have become available and combination therapies are now being approved for patients with and without renal impairment. Patients with HCV-MCS achieved sustained virologic response in 297 out of 313 patients (95%) treated with direct-acting antiviral therapy, and 85% had a complete or partial clinical response of MCS symptoms. Current direct-acting antiviral therapies are well tolerated in patients with HCV-MCS and only 1.6% discontinued treatment early. Patients with cryoglobulinemic glomerulonephritis also had an excellent cure rate (94%). The majority improved; 17/52 (33%) experienced full remission and 15/52 (29%) experienced partial remission. There were no reports of worsening kidney function in patients treated with direct-acting antiviral therapies. Less than 5% of patients with HCV-MCS treated with IFN-free direct-acting antiviral therapy required immunosuppression. However, patients with severe vasculitis appear to still require concomitant immunosuppression.

Advances in HCV and Cryoglobulinemic Vasculitis in the Era of DAAs: Are We at the End of the Road?

Hepatitis C Virus (HCV)-related Mixed Cryoglobulinemia (MC) is a unique condition with complex pathogenesis that involves HCV antigen-driven B-lymphocyte clonal proliferation and mutagenesis. Clinical spectrum of MC ranges from asymptomatic state to clinically-apparent vasculitis involving multiple organs. In the era of Direct-Acting Antiviral (DAA) therapy, patients with HCV-related MC achieve high rates of viral clearance that is commonly accompanied by an improvement in clinical symptoms as well as immunological profiles. Rituximab, either alone or in combination with DAA, has also been shown to be effective. Nevertheless, there have been limited and somewhat conflicting data, particularly over the long-term, regarding the rate and degree of clinical response of MC following DAA therapy. It appears that we have come quite a long way in the last decade with this condition. As with non-MC related HCV, undoubtedly long term outcome data will be forthcoming over the next few years. As we move forward successful therapy of HCV is not likely to be a challenge in contrast to access to therapy.

Interferon Therapy for HCV-Associated Glomerulonephritis: Meta-Analysis of Controlled Trials

Background

A relationship between hepatitis C virus (HCV) infection and chronic glomerulonephritis (GN) has been asserted on the grounds of epidemiological and experimental data. Although this suggests a role for an antiviral approach to HCV-associated GN instead of the more conventional immunosuppressive (or supportive) therapy, the optimal management of HCV-related glomerulonephritis remains controversial.

Objective

To compare antiviral with immunosuppressive therapy for HCV-associated GN.

Design

Meta-analysis of controlled clinical trials (CCTs) of the two treatments (antiviral versus immunosuppressive) of HCV-associated GN.

Methods

We used the fixed or random effects model of DerSimonian and Laird, with heterogeneity and sensitivity analyses. The rate of proteinuria and serum creatinine decrease after therapy for HCV-associated GN were regarded as the most reliable outcome end-points.

Results

We identified six studies involving 145 unique patients with HCV-associated GN. Pooling of study results demonstrated that proteinuria decreased more commonly after IFN than corticosteroid therapy (OR 1.92 (95% CI, 0.39; 9.57), NS), P-test for heterogeneity, 0.06 (I2=52.9%). In a sensitivity analysis including only CCTs using standard IFN-doses, OR was 3.86 (95% CI, 1.44; 10.33, (P=0.007)), P-test for heterogeneity, 0.18 (I2=35.9%). No improvement of serum creatinine after IFN compared to immunosuppressive therapy was noted (OR, 0.59 (95% CI, 0.21; 1.65), NS), P-test for heterogeneity, 0.76 (I2=0%). Only three CCTs gave information on the rate of proteinuria decrease over follow-up (OR, 5.08 (95% CI, 0.69; 37.31), NS). A few major side effects were noted after IFN administration.

Conclusions

Our meta-analysis indicates that standard IFN-doses were more effective than immunosuppressive therapy in lowering proteinuria of patients with HCV-related glomerulonephritis. However, no significant improvement in serum creatinine was seen by IFN or steroid therapy across the studies. Also, information on proteinuria recurrence after the completion of antiviral therapy was not sufficient. Prospective, randomized trials based on combined antiviral therapy (pegylated IFN plus ribavirin) with adequate dose and follow-up are required to assess the efficacy and safety of antiviral treatment of HCV-associated glomerulonephritis.

Hepatitis C Virus-associated Membranoproliferative Glomerulonephritis Treated with Directly Acting Antiviral Therapy

Hepatitis C virus (HCV) infection has been shown to affect kidneys with various histopathological pattern on the kidney biopsy. These commonly include a membranoproliferative glomerulonephritis (MPGN) pattern with mixed cryoglobulinemia (CG), thrombotic microangiopathy, membranous nephropathy, and vasculitis affecting medium and small vessels of the kidneys causing polyarteritis nodosa. It has been rarely associated with MPGN without detectable CG. We present one such patient who presented to us with HCV-associated MPGN without detectable CG, who recovered completely with directly acting antiviral therapy without any immunosuppression.

Daclatasvir/asunaprevir based direct-acting antiviral therapy ameliorate hepatitis C virus-associated cryoglobulinemic membranoproliferative glomerulonephritis: a case report

Background

Direct-acting antivirals (DAAs) dramatically improve the treatment of hepatitis C virus (HCV) infections. However, the effects of DAAs on extra-hepatic manifestations such as HCV-associated glomerulonephritis, especially in cases with renal dysfunction, are not well elucidated.

Case presentation

A 69-year-old Japanese woman was diagnosed as having chronic hepatitis C, genotype 1b at the age of 55. She presented with hypertension, microscopic hematuria, proteinuria, renal dysfunction, purpura, and arthralgia at the age of 61. She also had hypocomplementemia and cryoglobulinemia. Renal biopsy revealed membranoproliferative glomerulonephritis (MPGN), and she was diagnosed as having HCV-associated cryoglobulinemic MPGN. She declined interferon therapy at the time and was treated with antihypertensive medications as well as oral corticosteroid that were effective in reducing proteinuria. However, when the corticosteroid dose was reduced, proteinuria worsened. She began antiviral treatment with daclatasvir/asunaprevir (DCV/ASV). Clearance of HCV-RNA was obtained by 2 weeks and sustained, and liver function was normalized. In addition, microhematuria turned negative, proteinuria decreased, hypocomplementemia and estimated glomerular filtration rate were improved, whereas cryoglobulinemia persisted. She completed 24 weeks of therapy without significant adverse effects.

Conclusion

In a case of HCV-associated cryoglobulinemic MPGN with renal dysfunction, DCV/ASV -based DAAs ameliorated microhematuria, proteinuria and renal function without significant side effects.

A Rare Case of Hepatitis C-Associated Cryoglobulinemic Duodenal Vasculitis

Intestinal involvement of cryoglobulinemia is an uncommon manifestation and marker of severe vasculitis. We describe the case of a woman admitted to our service for management of acute renal failure and progressive gastrointestinal symptoms after initiating hepatitis C virus treatment with ribavirin and sofosbuvir 4 weeks prior. With an undetectable hepatitis C viral load and persistent symptoms despite hepatitis C virus therapy cessation, an upper endoscopy revealed duodenal sloughing, erythema, and bleeding, sparking suspicion for recurrence of cryoglobulinemic vasculitis.

Therapeutic Advances in HCV Genotype 1 Infection: Insights from the Society of Infectious Diseases Pharmacists

Hepatitis C virus (HCV) is the most common blood-borne infection in the United States. The high morbidity and mortality due to untreated infection have prompted updated screening recommendations that now include one-time HCV screening for all patients born between 1945 and 1965, in addition to risk factor-based screening. Current guidelines recommend treatment for all patients with chronic HCV. Treatment for HCV genotype 1 has evolved dramatically since the approval of the direct-acting antivirals. The approval of ledipasvir-sofosbuvir, ombitasvir-paritaprevir-ritonavir and dasabuvir, and simeprevir with sofosbuvir has dramatically altered the treatment landscape. High sustained virologic response (SVR) rates favor treatment, yet access to care poses a challenge for patients and providers. Current and emerging data with new therapies indicate high SVR rates in treatment-naïve and treatment-experienced patients, including patients with cirrhosis and in other special populations. Additional data suggest the addition of ribavirin can decrease treatment duration without compromising SVR rates. Resistance is an increasing area of interest in HCV, with baseline mutations identified and the potential for the development of resistance-associate variants in patients undergoing treatment. Due to the rapid evolution of HCV treatment, pharmacists should address challenges and play an integral role in agent selection, dosing, drug interaction screening, adverse effect monitoring, and the coordination of treatment. Clinical application of the latest information will reduce patient risk and improve outcomes.

Hepatitis C virus infection in nephrology patients

CONTEXT

Hepatitis C virus (HCV) infection leads to chronic liver disease, but also to extra-hepatic manifestations.

EVIDENCE ACQUISITIONS

Directory of Open Access Journals (DOAJ), Google Scholar, Pubmed (NLM), LISTA (EBSCO) and Web of Science have been searched.

RESULTS

Herein, we provide an overview of renal diseases related to HCV and their therapies, as well as the treatment options available for HCV (+)/RNA (+) dialysis patients. We will not mention, however, HCV infection-related complications in the post-kidney transplantation setting.

CONCLUSIONS

Extra-hepatic manifestations of HCV infection include mixed cryoglobulinemia, lymphoproliferative disorders, and renal disease. HCV infection has been reported in association with distinct histological patterns of glomerulonephritis in native kidneys.

Chronic kidney disease in homeless persons in Mexico

Little is known about the prevalence of chronic kidney disease (CKD) among the homeless in Mexico. The role of substance abuse, alcoholism, and homelessness in CKD has not been properly evaluated. We screened 260 homeless individuals in the state of Jalisco, Mexico, for the presence of CKD and its risk factors, and compared their characteristics with those from a separate cohort of poor Jalisco residents and with a survey of the general Mexican population. CKD was more prevalent among the homeless than among the poor Jalisco population (22% vs. 15.8%, P=0.0001); 16.5% had stage 3, 4.3% stage 4, and 1.2% stage 5. All were unaware of having CKD. Only 5.8% knew they had diabetes, but 19% had fasting blood sugar >126 mg/dl; 3.5% knew they were hypertensive but 31% had systolic blood pressure ⩾140 mm Hg or diastolic blood pressure ⩾90 mm Hg. Alcoholism was less common than in the poor Jalisco population (23.5% vs. 32.3%, P=0.002), but tobacco smoking (34.6% vs. 21.5%, P=0.0001) and substance abuse (18% vs. 1.1%, P=0.0001) were more prevalent among the homeless. Likewise, chronic viral infections such as HIV (4.5% vs. 0.3%, P=0.0001) and HCV (7.7% vs. 1.4%, P=0.0001) were also significantly higher among the homeless than in the general population. In conclusion, CKD and its risk factors are highly prevalent among the homeless individuals in Jalisco, Mexico. Lack of awareness of having diabetes and hypertension is highly common, as is substance abuse. Programs aiming to prevent CKD and its risk factors in Mexico should specifically target this high-risk population.

Remission of HCV-associated Glomerulonephritis with Pegylated IFN and Ribavirin Therapy after Liver Transplantation: Case Report and Literature Review

Background

Hepatitis C virus infection is associated with a variety of extrahepatic disorders such as membrano-proliferative glomerulonephritis, which is generally due to cryoglobulinemia.

Setting

We describe the case of one liver transplant recipient who received antiviral therapy (subcutaneous administration of peg-IFN-alpha-2a 180 mcg weekly and oral ribavirin 200 mg thrice a day) for HCV-related membrano-proliferative glomerulonephritis. He presented normal kidney function, non-nephrotic proteinuria (2 g/24 h) and mild hematuria.

Results

Urinary abnormalities disappeared within a few weeks after the initiation of antiviral therapy; however, combination antiviral therapy was not able to obtain viral clearance. After 11 months, IFN-therapy was interrupted and the patient continued low-dose ribavirin monotherapy (200 mg once per day) for one additional year- remission of proteinuria (<0.3 g/24 h) and hematuria persisted with intact kidney function. Although other mechanisms cannot be excluded, we suggest that ribavirin therapy was critically implicated in the remission of urinary abnormalities in our patient. The existing literature on the association between HCV-associated glomerulonephritis and therapy with ribavirin is reviewed.

Conclusions

Antiviral therapy may be effective in patients with HCV-induced glomerulonephritis. Further evidence is needed to evaluate efficacy and safety of ribavirin monotherapy for HCV-related glomerulonephritis.

Advances in the understanding of transplant glomerulopathy

Transplant glomerulopathy is a sign of chronic kidney allograft damage. It has poor survival and no effective therapies. This entity develops as a maladaptive repair/remodeling response to sustained endothelial injury and is characterized by duplication/multilamination of capillary basement membranes. This review provides up-to-date information for transplant glomerulopathy, including new insights into underlying causes and mechanisms, and highlights unmet needs in diagnostics. Transplant glomerulopathy is widely accepted as the principal manifestation of chronic antibody-mediated rejection, mostly with HLA antigen class II antibodies. However, recent data suggest that at least in some patients, there also is an association with hepatitis C virus infection, autoimmunity, and late thrombotic microangiopathy. Furthermore, intragraft molecular studies reveal nonresolving inflammation after sustained endothelial injury as a key mechanism and therapeutic target. Unfortunately, current international criteria rely heavily on light microscopy and miss patients at early stages, when they likely are treatable. Therefore, better tools, such as electron microscopy or molecular probes, are needed to detect patients when kidney injury is in an early active phase. Better understanding of causes and effector mechanisms coupled with early diagnosis can lead to the development of new therapeutics for transplant glomerulopathy and improved kidney outcomes.

Antiviral therapy for HCV-associated cryoglobulinemic glomerulonephritis: case report and review of the literature

We describe the case of a 51-year-old woman with HCV-associated cryoglobulinemic glomerulonephritis (GN). She presented mild deterioration of kidney function, non-nephrotic proteinuria, and active urinary sediment. Kidney biopsy showed features of membranoproliferative changes with some sclerosis. Sustained viral response (SVR) was obtained by 6 months of antiviral therapy (peg-IFN-α2a plus ribavirin). SVR was linked with improvement of kidney function and remission of proteinuria. Clinical and virological remission persists over a 25-month follow-up. This case report emphasizes efficacy and safety of antiviral treatment of HCV-associated glomerulonephritis--preliminary but encouraging results exist. We identified by systematic review of the literature 9 studies (156 unique patients); the pooled estimate of frequency of sustained virological response after IFN-based therapy was 0.49 (95% confidence interval, CI: 0.21, 0.77; p < 0.0005; random effects model). Heterogeneity was found (I(2) = 98.9%, p < 0.0001). Two possible regimens should be considered for the treatment of HCV-associated cryoglobulinemic GN according to the clinical presentation. Immunosuppressive therapy is recommended for HCV-related kidney disease having aggressive course, and recent evidence supports rituximab (RTX) use with a reduced exposure to corticosteroids. We identified six studies (66 unique patients) on RTX therapy for HCV-associated kidney disease; at the end of RTX therapy, the pooled estimate of the mean decrease in proteinuria was 1.4 g/24 h (95% CI: 0.75, 2.05, p < 0.001); The p test for heterogeneity gave a value of 0.94 (I(2) = 0). Several questions related to RTX use remain. HCV-induced GN is uncommon among CKD patients of developed countries, and this clearly hampers prospective controlled clinical trials aimed to evaluate efficacy and safety of antiviral or immunosuppressive therapy in this population.

Autoimmune manifestations in viral hepatitis

Infections by the viruses responsible for hepatitis B, C and D are accompanied by a number of immunopathological manifestations. A link between infection and autoimmunity is particularly well documented for the hepatitis C virus. Immunopathological manifestations range from production of autoantibodies to overt autoimmune disease, including thyroiditis and autoimmune hepatitis, and to immune-complex-mediated disorders, including cryoglobulinaemia, glomerulonephritis and vasculitis. Several of these manifestations improve with successful antiviral treatment, directly incriminating the virus in their pathogenesis. Mechanisms considered responsible for hepatitis virus-related immunopathology, including molecular mimicry, impairment of regulatory T cells and activation of B lymphocytes, will be examined in this review.

Kidneys in chronic liver diseases

Acute kidney injury (AKI), defined as an abrupt increase in the serum creatinine level by at least 0.3 mg/dL, occurs in about 20% of patients hospitalized for decompensating liver cirrhosis. Patients with cirrhosis are susceptible to developing AKI because of the progressive vasodilatory state, reduced effective blood volume and stimulation of vasoconstrictor hormones. The most common causes of AKI in cirrhosis are pre-renal azotemia, hepatorenal syndrome and acute tubular necrosis. Differential diagnosis is based on analysis of circumstances of AKI development, natriuresis, urine osmolality, response to withdrawal of diuretics and volume repletion, and rarely on renal biopsy. Chronic glomerulonephritis and obstructive uropathy are rare causes of azotemia in cirrhotic patients. AKI is one of the last events in the natural history of chronic liver disease, therefore, such patients should have an expedited referral for liver transplantation. Hepatorenal syndrome (HRS) is initiated by progressive portal hypertension, and may be prematurely triggered by bacterial infections, nonbacterial systemic inflammatory reactions, excessive diuresis, gastrointestinal hemorrhage, diarrhea or nephrotoxic agents. Each type of renal disease has a specific treatment approach ranging from repletion of the vascular system to renal replacement therapy. The treatment of choice in type 1 hepatorenal syndrome is a combination of vasoconstrictor with albumin infusion, which is effective in about 50% of patients. The second-line treatment of HRS involves a transjugular intrahepatic portosystemic shunt, renal vasoprotection or systems of artificial liver support.

Basic and translational concepts of immune-mediated glomerular diseases

Genetically modified immune responses to infections and self-antigens initiate most forms of GN by generating pathogen- and danger-associated molecular patterns that stimulate Toll-like receptors and complement. These innate immune responses activate circulating monocytes and resident glomerular cells to release inflammatory mediators and initiate adaptive, antigen-specific immune responses that collectively damage glomerular structures. CD4 T cells are needed for B cell-driven antibody production that leads to immune complex formation in glomeruli, complement activation, and injury induced by both circulating inflammatory and resident glomerular effector cells. Th17 cells can also induce glomerular injury directly. In this review, information derived from studies in vitro, well characterized experimental models, and humans summarize and update likely pathogenic mechanisms involved in human diseases presenting as nephritis (postinfectious GN, IgA nephropathy, antiglomerular basement membrane and antineutrophil cytoplasmic antibody-mediated crescentic GN, lupus nephritis, type I membranoproliferative GN), and nephrotic syndrome (minimal change/FSGS, membranous nephropathy, and C3 glomerulopathies). Advances in understanding the immunopathogenesis of each of these entities offer many opportunities for future therapeutic interventions.

Treatment of hepatitis C-mediated glomerular disease

Chronic kidney disease (CKD) is becoming a major public health issue worldwide, mainly due to the increasing prevalence of hypertension, diabetes and aging population. Chronic hepatitis C virus (HCV) infection commonly involves the kidneys, can be a cause of CKD, and significantly impacts morbidity and mortality in these patients. Prompt recognition and knowledge of how to best manage these patients are essential in order to have a successful renal outcome. Patients with HCV and kidney involvement can often be managed with a specific combination of antiviral drugs, immunosuppressants, plasmapheresis, and newer monoclonal antibodies. However, no large randomized controlled trials have been conducted in this patient population, optimal management of HCV-mediated kidney diseases is not well defined, and treatment itself can be associated with significant toxicity in patients with CKD. This article reviews the recent literature, discusses the limitations of current therapies, as well as toxicity associated with treatment, and suggests future areas for research.

Overlapping pathways to transplant glomerulopathy: chronic humoral rejection, hepatitis C infection, and thrombotic microangiopathy

Transplant glomerulopathy (TG) has received much attention in recent years as a symptom of chronic humoral rejection; however, many cases lack C4d deposition and/or circulating donor-specific antibodies (DSAs). To determine the contribution of other causes, we studied 209 consecutive renal allograft indication biopsies for chronic allograft dysfunction, of which 25 met the pathological criteria of TG. Three partially overlapping etiologies accounted for 21 (84%) cases: C4d-positive (48%), hepatitis C-positive (36%), and thrombotic microangiopathy (TMA)-positive (32%) TG. The majority of patients with confirmed TMA were also hepatitis C positive, and the majority of hepatitis C-positive patients had TMA. DSAs were significantly associated with C4d-positive but not with hepatitis C-positive TG. The prevalence of hepatitis C was significantly higher in the TG group than in 29 control patients. Within the TG cohort, those who were hepatitis C-positive developed allograft failure significantly earlier than hepatitis C-negative patients. Thus, TG is not a specific diagnosis but a pattern of pathological injury involving three major overlapping pathways. It is important to distinguish these mechanisms, as they may have different prognostic and therapeutic implications.

Chronic viral hepatitis and chronic kidney disease

Chronic kidney disease (CKD) has become a major public health problem worldwide over the past few decades because of the increasing prevalence of hypertension, diabetes mellitus, and elderly individuals in most countries. Chronic viral hepatitis (due to hepatitis B virus (HBV) and hepatitis C virus (HCV)) also poses significant morbidity and mortality globally. Both these viruses can cause CKD and these infections can occur as a consequence of CKD management. CKD patients acquiring HBV or HCV infection have higher morbidity and mortality rates, and the management of these infections among CKD patients with antiviral agents is associated with high rates of adverse effects. The optimal management of CKD associated with HBV and HCV is not well defined because of insufficient data from clinical trials. This review discusses the pathogenesis, clinical characteristics and management issues related to chronic viral hepatitis and CKD.

Successful treatment of HCV-related cryoglobulinemic glomerulonephritis with double-filtration plasmapheresis and interferon combination therapy

A 67-year-old, hepatitis C virus (HCV)-positive woman was admitted to our hospital because of proteinuria and leg edema. Laboratory examination showed decreased serum albumin and complement activity and positive cryoglobulin. The HCV RNA genotype was 1b with high viral load. Kidney biopsy showed membranoproliferative glomerulonephritis (MPGN) with capillary deposition of C3, IgM, and IgG, indicating HCV-associated glomerulonephritis. In addition to interferon (IFN) therapy, double-filtration plasmapheresis (DFPP) was performed to reduce HCV RNA blood levels in the early stage of IFN therapy. This treatment greatly reduced the viral load and induced clinical remission of MPGN, suggesting that DFPP plus IFN combination therapy may represent a potentially effective modality for refractory-type HCV-associated glomerulonephritis.

Increased prevalence of reduced estimated glomerular filtration rate in chronic hepatitis C patients

BACKGROUND

To investigate the prevalence and severity of reduced estimated glomerular filtration rate (eGFR) in patients with chronic hepatitis C (CHC).

METHODS

Medical record review of 831 consecutive CHC patients seen in our clinic between July 2000 and August 2003; eGFR was estimated using the abbreviated Modification of Diet in Renal Disease (aMDRD) equation. The stage of kidney disease was determined based on eGFR expressed in milliliters per minute per 1.73 m(2): stage 1 (signs of kidney damage but normal or elevated (eGFR >or= 90), stage 2 (eGFR 60-89), stage 3 (30-59), stage 4 (eGFR 15-29), stage 5 (eGFR < 15 or dialysis-dependent).

RESULTS

A total of 522 patients had available data with using the aMDRD equation, 51% had abnormal eGFR (stage 1, 4.6%; stage 2, 36.4%; stage 3 or 4, 6.1%; stage 5, 3.8%). Of 190 patients with stage 2 kidney disease, 189 patients (99.5%) had normal serum creatinine and only one patient (0.5%) had elevated creatinine concentrations (>1.4 mg/dl). Of the 32 patients with stage 3 or 4 disease, 20 (62.5%) had a normal serum creatinine concentration. Of 349 patients without diseases known to cause renal insufficiency, 38% had stage 2-4 renal disease. In a subset of these patients, 95/522 (18%) the measured creatinine clearance showed good correlation with their aMDRD (R = 0.47, (p < 0.0001).

CONCLUSIONS

In CHC patients, a normal serum creatinine concentration does not assure normal kidney function. Estimation of eGFR with the aMDRD equation is a more accurate method of identifying patients with chronic kidney disease and reduced eGFR. Therefore, CHC patients should be screened more rigorously for chronic kidney disease because of the high prevalence of reduced eGFR. Lastly, in all CHC patients, the aMDRD eGFR should be used in each encounter with these patients when assessing their renal function irrespective of their serum creatinine.

Management of hepatitis C virus-related mixed cryoglobulinemia

Mixed cryoglobulinemia is a chronic immune complex-mediated disease strongly associated with hepatitis C virus (HCV) infection. Mixed cryoglobulinemia is a vasculitis of small and medium-sized arteries and veins, due to the deposition of complexes of antigen, cryoglobulin and complement in the vessel walls. The main clinical features of mixed cryoglobulinemia vasculitis include the triad of palpable purpura, arthralgias, and weakness, and other pathological conditions such as glomerulonephritis, peripheral neuropathy, skin ulcers, and widespread vasculitis. The treatment of HCV-related mixed cryoglobulinemia is difficult due to the multifactorial origin and clinical polymorphism of the syndrome. It can be directed to eradicate the HCV infection, suppress the B-cell clonal expansion and cryoglobulin production, or ameliorate symptoms. The choice of the most appropriate treatment is strictly related to the assessment of disease activity, and to the extent and severity of organ involvement.

The Clinical Application of Ozonetherapy

The reader may be eager to examine in which diseases ozonetherapy can be proficiently used and she/he will be amazed by the versatility of this complementary approach (Table 9 1). The fact that the medical applications are numerous exposes the ozonetherapist to medical derision because superficial observers or sarcastic sceptics consider ozonetherapy as the modern panacea. This seems so because ozone, like oxygen, is a molecule able to act simultaneously on several blood components with different functions but, as we shall discuss, ozonetherapy is not a panacea. The ozone messengers ROS and LOPs can act either locally or systemically in practically all cells of an organism. In contrast to the dogma that “ozone is always toxic”, three decades of clinical experience, although mostly acquired in private clinics in millions of patients, have shown that ozone can act as a disinfectant, an oxygen donor, an immunomodulator, a paradoxical inducer of antioxidant enzymes, a metabolic enhancer, an inducer of endothelial nitric oxide synthase and possibly an activator of stem cells with consequent neovascularization and tissue reconstruction.

Transplantation in the patient with hepatitis C

Hepatitis C virus (HCV) infection is the most frequent cause of liver disease after renal transplantation. Its clinical course is irrelevant in the short term, except for rare cases of fibrosing cholestatic hepatitis. However, in the long run, HCV infection can lead to major liver complications. Because interferon (IFN) is generally contraindicated in renal transplant patients, the best approach is to treat patients on dialysis. Until more information with pegylated-IFN is available, the use of alpha-IFN monotherapy is recommended. Most of the patients with sustained virological response remain HCV RNA negative after transplantation. HCV-positive renal transplant patients have a higher risk for proteinuria, chronic rejection, infections and post-transplant diabetes (PTDM). Long-term patient- and graft-survival rates are lower in HCV-positive patients. Mortality is higher, mainly as a result of liver disease and infections. HCV can contribute to the development of certain neoplasias such as post-transplant lymphoproliferative disease (PTLD). HCV infection is also an independent risk factor for graft loss. PTDM, transplant glomerulopathy and HCV-related glomerulonephritis can contribute to graft failure. Despite this, transplantation is the best option for end-stage renal disease in HCV-positive patients. Several measures to minimize the consequences of HCV infection have been recommended. Adjustment of immunosuppression and careful follow up in the outpatient clinic for early detection of HCV-related complications are mandatory.

Renal failure in patients with cirrhosis

Renal failure in cirrhosis poses unique diagnostic and therapeutic challenges. Laboratory values and predictive equations grossly overestimate renal function in patients with cirrhosis. Development of renal failure connotes a worse prognosis; mortality is especially high with hepatorenal syndrome. Classification of the causes of renal failure in patients with cirrhosis is provided with more extensive discussion of selected causes. Finally, a suggested diagnostic approach to renal failure in cirrhosis is given.

Current status and issues of C1q nephropathy

C1q nephropathy, first proposed by Jennette and Hipp [Am J Clin Pathol 83:415-420, 1985; Am J Kidney Dis 6:103-110, 1985], was described as a distinct glomerular disease entity characterized by extensive mesangial deposition of C1q, with associated mesangial immune complexes, and the absence of any clinical and laboratory evidence of systemic lupus erythematosus. Now, 20 years since the first report, the disease entity is gradually attaining recognition, particularly in the field of pediatrics. C1q is the subcomponent of C1 in the classical pathway of complement activation. Generally, C1q deposition is caused by the activation of C1 by immunoglobulin G (IgG) and IgM; therefore, C1q nephropathy is considered as an immune complex glomerulonephritis. However, in C1q nephropathy, it remains unclear whether the deposition of C1q in the glomeruli is in response to the deposition of immunoglobulin or immune complex, or whether deposition is non-specific trapping that accompanies increased glomerular protein trafficking associated with proteinuria. Since not only the pathogenesis of C1q deposition in glomeruli but also its significance are still uncertain, it has not yet been established as an independent disease. From recent publications of the clinical and pathological characterizations, C1q nephropathy has been thought to be a subgroup of primary focal segmental glomerular sclerosis. However, many reports describe different symptoms, histopathologies, therapeutic responses and prognoses, suggesting that C1q nephropathy is not a single disease entity, but that it may be a combination of several disease groups. There are many uncertain areas requiring further investigation, though it is hoped that a detailed examination of future cases will clarify the subgroups making up C1q nephropathy and their clinicopathological characteristics, and will lead to the establishment of C1q nephropathy as an independent disease entity.

Prevalence of hepatitis B and C markers in glomerular diseases

OBJECTIVE

To study the prevalence of hepatitis B and C viruses in patients with glomerulonephritis (Gn). Material and methods. This was a retrospective study of 89 patients (36 females, 53 males) diagnosed with Gn. Infection with hepatitis B and C was studied by means of serological methods; if patients presented hepatitis C antibodies, the presence of viral RNA in serum was detected by means of quantitative polymerase chain reaction. The control group comprised 59,546 first-time blood donors.

RESULTS

None of the patients were positive for hepatitis B surface antigen (HBsAg). In the control group there were 168 HBsAg positives. The prevalence of HBsAg in the control group (0.28%) was not significantly different (p = 0.614) from that in the patient group. Four patients with Gn were positive for hepatitis C virus (HCV) antibodies, and in three of these RNA HCV was also positive. The histological diagnoses in the four cases with HCV antibodies were: focal and segmental glomerulosclerosis; crescentic IgA nephropathy; diffuse proliferative Gn; and membranous Gn. The first three patients also presented other pathologies potentially linked to Gn, namely left renal agenesis, heavy alcohol intake/chronic liver disease and HIV seropositivity, respectively. Only the patient with membranous Gn, in whom other causes were disregarded, received antiviral treatment, although RNA HCV remained positive. In the control group, 141 cases were positive for HCV antibodies (prevalence 0.24%). The prevalence in the study group was significantly higher (p < 0.001).

CONCLUSION

HCV is more prevalent in patients with Gn than in those without, and this is the opposite of the situation with HBsAg.

HCV-related autoimmune and neoplastic disorders: the HCV syndrome

Hepatitis C virus (HCV) chronic infection may be associated with a great number of both hepatic and extrahepatic manifestations. HCV lymphotropism is responsible for poly-oligoclonal B-lymphocyte expansion, which is the common underlying alteration in a significant percentage of HCV-infected individuals. The consequent production of different autoantibodies and immune-complexes, including cryoglobulins, may lead to organ- and non-organ-specific immunological alterations. Mixed cryoglobulinemia, a small-vessel systemic vasculitis, is characterized by the coexistence of autoimmune and lymphoproliferative alterations; therefore, it represents the prototype of HCV-associated disorders. Moreover, HCV shows an oncogenic potential; several studies support its pathogenetic link with some malignancies, mainly hepatocellular carcinoma and B-cell lymphomas. On the whole, HCV-related disorders present a heterogeneous geographical distribution, suggesting a role of other important genetic and/or environmental cofactors. While the majority of HCV-infected individuals is asymptomatic or may develop only liver manifestations, a significant percentage of them may develop a variable combination of autoimmune lymphoproliferative disorders. The resulting multiform clinico-pathological condition can be termed HCV syndrome. The natural history of HCV syndrome is the expression of multifactorial and multistep pathogenetic process, which usually proceeds from mild, often isolated manifestations to systemic immune-mediated disorders, and less frequently to overt malignancies.

Emerging Paradigms in the Renal Pathology of Viral Diseases

This review considers recent information that illuminates pathogenetic mechanisms that involve three of the major viral infections that cause renal injury in the form of HIV-associated nephropathy, polyoma virus nephropathy, and hepatitis C virus-associated glomerulonephritis.

Hepatitis C virus-related lymphoproliferative disorders: An overview

Hepatitis C virus (HCV) is a global health problem affecting 3% of the world's population (about 180 million) and a cause of both hepatic and extrahepatic diseases. B-cell lymphoproliferative disorders, whose prototype is mixed cryoglobulinemia, represent the most closely related as well as the most investigated HCV-related extrahepatic disorder. The association between extrahepatic (lymphoma) as well as hepatic malignancies (hepatocellular carcinoma) has justified the inclusion of HCV among human cancer viruses. HCV-associated manifestations also include porphyria cutanea tarda, lichen planus, nephropathies, thyreopathies, sicca syndrome, idiopathic pulmonary fibrosis, diabetes, chronic polyarthritis, sexual dysfunctions, cardiopathy/atherosclerosis, and psychopathological disorders. A pathogenetic link between HCV virus and some lymphoproliferative disorders was confirmed by their responsiveness to antiviral therapy, which is now considered the first choice treatment. The aim of the present paper is to provide an overview of extrahepatic manifestations of HCV infection with particular attention to B-cell lymphoproliferative disorders. Available pathogenetic hypotheses and suggestions about the most appropriate, currently available, therapeutic approaches will also be discussed.

Extrahepatic manifestations of Hepatitis C Virus infection: a general overview and guidelines for a clinical approach

Hepatitis C Virus is associated with a wide series of extrahepatic manifestations. Based on available data the link between the virus and some of these extrahepatic diseases is only suggested and needs further confirmation. Hepatitis C Virus-related lymphoproliferative disorders, whose prototype is mixed cryoglobulinaemia, represent the most closely related extrahepatic manifestations of Hepatitis C Virus. Other Hepatitis C Virus-associated disorders include nephropathies, thyreopathies, sicca syndrome, idiopathic pulmonary fibrosis, porphyria cutanea tarda, lichen planus, diabetes, chronic polyarthritis, cardiopathy and atherosclerosis. A pathogenetic link between Hepatitis C Virus and some extrahepatic manifestations was confirmed by their responsiveness to antiviral therapy, which is now deemed the first therapeutic option to consider. By contrast, there are diseases where treatment with interferon was ineffective or dangerous. The aim of the present paper is to outline the most recent evidence concerning extrahepatic disorders that are possibly associated with Hepatitis C Virus infection. Special emphasis will be given to discussion of the most appropriate clinical approaches to be adopted in order to diagnose, treat (possibly prevent) and follow-up extrahepathic diseases in patients with Hepatitis C Virus infection.

Predictive factors for chronic renal failure one year after orthotopic liver transplantation

Chronic renal failure (CRF) is increasingly prevalent in solid-organ-transplant patients. This is in part related to the long-term use of calcineurin inhibitor (CNI) agents. However, in orthotopic liver-transplant (OLT) patients, the effects of superimposed hepatitis C virus (HCV)-related renal lesions could also be a factor. The aim of this cohort study (February 2000 to September, 2003) was to identify the predictive factors at one year post-transplantation for CRF in OLT patients associated with induction therapies. CRF was defined as having a creatinine clearance (CC) lower than 60 mL/min. Of the 97 transplants performed during that period, 72 were still functioning after one year. Of these, 33 patients (45.8%) had CRF. In univariate analysis, the predicting factors for CRF were recipient sex (female), initial liver disease (HCV-related cirrhosis), pre-transplant CC (<80 mL/mn), and post-transplant serum creatinine >130 micromol/L at day 3 and months (M) 1, 3, and 6. In multivariate analysis, the independent predictive factors for CRF included female sex [OR: 11.5 (2.3-58.3); p = 0.003], HCV infection [OR: 5.01 (1.1-22.7); p = 0.03], pre-OLT CC <80 mL/mn [OR: 5.4 (1.2-23.7); p = 0.025], and serum creatinine at M6 greater than 130 micromol/L [OR: 19.6 (3.7-102.5); p = 0.0004]. Among all of the predictive factors for post-OLT CRF, only one is modifiable: post-transplant serum creatinine, which could be, to some extent, related to the long-term use of CNIs.

Chronic nephropathies of cocaine and heroin abuse: a critical review

Renal disease in cocaine and heroin users is associated with the nephrotic syndrome, acute glomerulonephritis, amyloidosis, interstitial nephritis, and rhabdomyolysis. The pathophysiologic basis of cocaine-related renal injury involves renal hemodynamic changes, glomerular matrix synthesis and degradation, and oxidative stress and induction of renal atherogenesis. Heroin is the most commonly abused opiate in the United States. Previous studies identified a spectrum of renal diseases in heroin users. The predominant renal lesion in black heroin users is focal segmental glomerulosclerosis and in white heroin users is membranoproliferative glomerulonephritis. Although the prevalence of heroin use in the United States has increased, the incidence of "heroin nephropathy" has declined. Because reports of heroin nephropathy predated the surveillance of hepatitis C virus and HIV, the varied findings might be related to the spectrum of viral illnesses that are encountered in injection drug users. Socioeconomic conditions, cultural and behavioral practices, or differences in genetic susceptibilities may be more associated with the development of nephropathy in heroin users than the drug's pharmacologic properties. Administration of cocaine in animal models results in nonspecific glomerular, interstitial, and tubular cell lesions, but there is no animal model of heroin-associated renal disease. The heterogeneity of responses that are associated with heroin is not consistent with a single or simple notion of nephropathogenesis. There are no well-designed, prospective, epidemiologic studies to assess the incidence and the prevalence of renal disease in populations of opiate users and to establish the validity of a syndrome such as heroin nephropathy. It is concluded although there is a paucity of evidence to support a heroin-associated nephropathy, the evidence from in vitro cellular and animal studies to support the existence of cocaine-induced renal changes is more convincing.

Extrahepatic manifestations of hepatitis C virus

Given the high prevalence of chronic hepatitis C virus (HCV) infection, its clinical sequelae account for a significant proportion of patients presenting to gastroenterologists and hepatologists. Whereas the hepatic manifestations of hepatitis C are well described, including hepatitis, cirrhosis, and the development of hepatocellular carcinoma, the extrahepatic manifestations, though common, are less well appreciated. Although nonspecific, fatigue and arthralgias are very common in those with chronic hepatitis C. Extrahepatic syndromes have been reported in as much as 36% of HCV patients, but the exact prevalence is not known. Patients with these syndromes can be divided into those with a high degree of association and those with a more moderate or mild association with HCV. The most prevalent extrahepatic diseases with the highest degree of association with HCV are the essential mixed cryoglobulins with skin, neurologic, renal, and rheumatologic complications. Non-cryoglobulin diseases with a less definite relationship to HCV include systemic vasculitis, splenic lymphoma, porphyria cutanea tarda, and the sicca syndromes. This article highlights the pathophysiology and clinical manifestations of these disorders.

Effect of chronic viral hepatitis on graft survival in Saudi renal transplant patients

BACKGROUND

In Saudi Arabia the prevalence of hepatitis C among hemodialysis patients is very high ranging from 60 to 80%. A large number of these dialysis patients go for renal transplant, resulting into a higher prevalence of hepatitis C virus (HCV) infection in renal transplant patients. Yet no current systematic report is available on the influence of hepatitis C status on patient and graft survival. The present study was therefore undertaken to address this objective.

METHODS

Retrospective analysis of data of 448 renal transplantation subjects was undertaken. The mean follow-up period was 5.85 +/- 2.7 (median 5.3) years. The factors associated with renal graft survival were reviewed and these include: age, sex, and type of donor, immunosuppressive medication, episodes of infection, blood pressure, serum creatinine, and status of hepatitis. The primary end-points were renal graft function and patient survival. Logistic regression, COX regression analysis, and Kaplan-Meier survival estimates were used to evaluate the influence of hepatitis C on the above parameters.

RESULTS

Among 448 recipients of first kidney transplant patients, 286 (63.8%) were positive for HCV infection. In the HCV-positive group, 204 (71.32%) were males. Kaplan-Meier survival analysis showed a significantly better graft survival for HCV-negative patients than HCV-positive patients (p < 0.001; log-rank test). Logistic regression analysis and COX regression analysis have shown different grades of graft dysfunction were present in HCV-positive patients after adjustment for covariates: age, sex, blood pressure, type of donor, and immunosuppressive medication; the presence of HCV was a major predictor of bad outcome and significantly influenced graft survival (odds ratio = 4.37; 95% Cl = 1.81-4.77). Significant deterioration of liver function was noted in HCV-positive patients at the last follow-up, taking ALT as a marker (ALT level 80.6 +/- 5.8 U/l at the last follow-up versus 49.5 +/- 32 U/l at baseline p < or = 0.0001). Sixteen patients had a chronic active course and 1 patient developed biopsy-proven liver cirrhosis and portal hypertension. A serious and significantly greater incidence of fatal chest infections was seen in HCV-positive patients. Although mortality was greater in HCV-positive versus HCV-negative patients (20 vs. 7), the difference did not attain statistical significance (p = 0.23) and none of the patients died as a result of hepatic failure.

CONCLUSION

The presence of HCV infection greatly influenced graft survival in renal transplant patients and a higher proportion of infected patients had renal and hepatic dysfunction. A significant increase in fatal chest infections was noted in HCV-positive patients. Overall mortality was higher in HCV-positive patients, but it was not statistically significant. All measures should be taken to prevent HCV transmission in the dialysis population. Renal transplant recipients with HCV infection need close monitoring for both graft and liver function.

Unresolved issues and current concepts in management of primary glomerulonephritis

The successful treatment of primary glomerulonephritis (GN) presenting with nephrotic syndrome in adults depends heavily on an accurate diagnosis. A successful diagnosis depends on a correct approach, combining light microscopy, immunofluorescence, and other special staining of renal biopsy material examined by a trained nephropathologist. A good clinical history and serological tests easily rule out possible secondary causes (for example, infection, autoimmune, metabolic or toxic) in most cases. Unfortunately, these procedures are not put into practice in most cases in developing countries, resulting in missed diagnosis and unnecessary steroid and immunosuppressant therapy with its inherent morbidity. Following the emergence of IgA and IgM nephropathies as very common forms of glomerular disorders in some countries, immunofluorescence has become absolutely necessary for their diagnosis. Moreover, a recent meta-analysis has defined different treatment protocols for minimal change nephropathy, focal segmental glomerulosclerosis, membranous nephropathy, and IgA nephropathy for a better outcome. This article emphasizes and elaborates on these issues for proper management of primary GN.