Alport syndrome misdiagnosed with IgA nephropathy from familial history: a case report and brief review

BACKGROUND

Alport syndrome is a rare inherited disease resulting from a primary disorder of the glomerular basement membrane. This disease results from mutations in genes encoding alpha chains of type IV collagen. In the differential diagnosis of this disease, IgA nephropathy is the most common primary glomerular disease with gross or microscopic hematuria.

CASE PRESENTATION

A 50-year-old woman was presented with microscopic hematuria and proteinuria of under one gram. Due to the diagnosis of IgA nephropathy in family members, she was treated and followed up for 4 years as a possible case of IgA nephropathy. Eye examination and audiometry were normal. She underwent renal biopsy with an exacerbation of proteinuria. There was no finding in favor of IgA nephropathy in the histological examination, but the findings of electron microscopy and family history favored Alport syndrome.

CONCLUSIONS

This case demonstrates the importance of accurate history and electron microscopy in the complete histological evaluation and diagnosis of glomerular disease. Although in most cases the two can be differentiated based on clinical manifestations, laboratory findings, and histopathological examination, sometimes the association of these two diseases in the families involved or the lack of accurate history and complete histological examinations can complicate the diagnosis.

The evolution of performing a kidney biopsy: a single center experience comparing native and transplant kidney biopsies performed by interventional radiologists and nephrologists

BACKGROUND

Kidney biopsy is the most vital tool guiding a nephrologist in diagnosis and treatment of kidney disease. Over the last few years, we have seen an increasing number of kidney biopsies being performed by interventional radiologists. The goal of our study was to compare the adequacy and complication rates between kidney biopsies performed by interventional radiology versus nephrology.  METHODS : We performed a single center retrospective analysis of a total of all kidney biopsies performed at our Institution between 2015 and 2021. All biopsies were performed using real-time ultrasound. Patients were monitored for four hours post biopsy and repeat ultrasound or hemoglobin checks were done if clinically indicated. The entire cohort was divided into two groups (Interventional radiology (IR) vs nephrology) based on who performed the biopsy. Baseline characteristics, comorbidities, blood counts, blood pressure, adequacy of the biopsy specimen and complication rates were recorded. Multivariable logistic regression was used to compare complication rates (microscopic hematuria, gross hematuria and need for blood transfusion combined) between these two groups, controlling for covariates of interest. ANCOVA (analysis of variance, controlling for covariates) was used to compare differences in biopsy adequacy (number of glomeruli per biopsy procedure) between the groups.

RESULTS

446 kidney biopsies were performed in the study period (229 native and 147 transplant kidney biopsies) of which 324 were performed by IR and 122 by nephrologist. There was a significantly greater number of core samples obtained by IR (mean = 3.59, std.dev. = 1.49) compared to nephrology (mean = 2.47, std.dev = 0.79), p < 0.0001. IR used 18-gauge biopsy needles while nephrologist exclusively used 16-gauge needles. IR used moderate sedation (95.99%) or general anesthesia (1.85%) for the procedures more often than nephrology, which used them only in 0.82% and 0.82% of cases respectively (p < 0.0001). Trainees (residents or fellows) participated in the biopsy procedures more often in nephrology compared to IR (97.4% versus 69.04%, p < 0.0001). The most frequent complication identified was microscopic hematuria which occurred in 6.8% of biopsies. For native biopsies only, there was no significant difference in likelihood of complication between groups, after adjustment for covariates of interest (OR = 1.01, C.I. = (0.42, 2.41), p = 0.99). For native biopsies only, there was no significant difference in mean number of glomeruli obtained per biopsy procedure between groups, after adjustment for covariates of interest (F(1,251) = 0.40, p = 0.53).

CONCLUSION

Our results suggest that there is no significant difference in the adequacy or complication rates between kidney biopsies performed by IR or nephrology. This conclusion may indicate that kidney biopsies can be performed safely with adequate results either by IR or nephrologists depending on each institution's resources and expertise.

Pathologic Correlation with Renal Dysfunction after Intravitreal Injections of Vascular Endothelial Growth Factor Antagonists

OBJECTIVE

Vascular endothelial growth factor (VEGF) antagonists have been used for treating metastatic neoplasms. It has also been known that one of its side effects is to cause proteinuria and renal failure in the setting of thrombotic microangiopathy (TMA). The underlying mechanism is likely due to the inhibition of VEGF production in podocytes, resulting in diffuse fusion of foot processes and impaired glomerular endothelial fenestrations, and leading to massive proteinuria and subsequent glomerular endothelium injury. Intravitreal injection of VEGF antagonists (IIVA) has been also used to treat macular degeneration and diabetic retinal neo-vascular proliferation. The majority of patients tolerate the treatment well. However, IIVA can lead to renal dysfunction including proteinuria and gradual renal failure as a rare side effect. The goal of this study was to report two cases related to the nephrotoxicity of IIVA and review the literature associated with this topic.

CASE REPORT

The first diabetic patient had elevated serum creatinine at 3.25 mg/dl and proteinuria/creatinine ratio at 6.1 after 48-month treatment of IIVA. The first renal biopsy revealed thrombotic microangiopathy that was correlated with his increased serum creatinine and nephrotic range of proteinuria. The second diabetic patient had increased serum creatinine up to 1.89 mg/dl but low proteinuria. The second biopsy showed acute tubular necrosis that was correlated with his elevated serum creatinine.

CONCLUSION

Intravitreal injection of VEGF antagonist can be associated with thrombotic microangiopathy and acute tubular necrosis, leading to renal dysfunction.

A Report of Chronic Intestinal Pseudo-obstruction Related to Systemic Lupus Erythematosus

Chronic intestinal pseudo-obstruction (CIPO) is a functional gastrointestinal disorder with symptoms of ileus. CIPO can either be idiopathic or secondary to other diseases such as systemic lupus erythematosus (SLE). SLE is involved in many parts of the gastrointestinal system with variable clinical presentations. Reports about reduplicated CIPO as a complication of SLE is infrequent. A 49-year-old female suffering from clinical symptoms of ileus has been hospitalized 3 times over 1 year. Her examination results showed no observation of mechanical obstruction. In August 2017, she came to the nephrology department due to edema in both lower limbs along with symptoms of ileus. After thorough examination, she was diagnosed with secondary CIPO related to SLE. Results of renal biopsy confirmed to be lupus nephritis (Class III-(A) + V). The symptoms of ileus are gradually improved after treatment of full-dose intravenous corticosteroid for 5 days.

The Spectrum of Biopsy-Proven Glomerular Disease in China: A Systematic Review

Background:

Chronic kidney disease has become a leading public health concern in China, as it is associated with increased morbidity, mortality, and costs. However, the overall situation regarding common glomerular diseases in China remains unclear. Hence, the aim of this study was to assess the national profile of the common types of glomerulonephritis in China.

Methods:

We searched Medline, Embase, Cochrane Library, CNKI, SinoMed, VIP, and Wanfang databases for English and Chinese language articles from inception to September 2017. We also collected potentially relevant studies and reviews using a manual search. The following words in combinations are as keywords: “renal biopsy”, “kidney pathological diagnosis”, and “spectrum of pathological types”.

Results:

We identified 23 studies involving 176,355 patients from 15 provinces/cities in China. The detection rates of primary glomerulonephritis (PGN) and secondary glomerulonephritis (SGN) were 0.740 and 0.221, respectively. Over the past 30 years, the top five types of PGN were immunoglobulin A nephropathy (IgAN; 24.3%), mesangial proliferative glomerulonephritis (MsPGN; 10.5%), membranous nephropathy (MN; 12.6%), minimal change disease (MCD; 9.8%), and focal segmental glomerulosclerosis (FSGS; 4.6%), and the top four types of SGN were lupus nephritis (LN; 8.6%), Henoch-Schönlein purpura glomerulonephritis (4.1%), hepatitis B virus-associated glomerulonephritis (HBV-GN; 2.6%), and diabetic nephropathy (DN; 1.6%). The proportion of MN, MCD, HBV-GN, and DN tended to increase, while those of IgAN, MsPGN, FSGS, and LN tended to drop.

Conclusions:

Although the incidence of SGN is increasing gradually, PGN is still the leading form of kidney disease in patients undergoing renal biopsies in China. IgAN and LN are the most common types of PGN and SGN, respectively. Differences between regions are related to various factors such as nationality, environment, and diet. Furthermore, unified standards and norms for evaluating renal biopsies are urgently needed.

Ultrastructural deposits appearing as "zebra bodies" in renal biopsy: Fabry disease?- comparative case reports

Background

Fabry Disease (FD) is a genetic disorder caused by alpha-galactosidase A deficiency. Certain drugs, such as hydroxychloroquine, can produce renal deposits that mimic morphological findings seen in FD, characterizing a type of drug-induced renal phospholipidosis.

Case presentation

Case 1: A 28-year-old female patient with systemic lupus erythematosus who had been using hydroxychloroquine for 14 months presented subnephrotic proteinuria. Renal biopsy showed deposits compatible with FD. Neither activity analysis of alpha-galactosidase A nor genetic analysis were available and were not performed. These deposits were not detected in a subsequent renal biopsy three years after withdrawal of the medication, characterizing a possible hydroxychloroquine-induced renal phospholipidosis. Case 2: A 29-year-old male patient presented with acroparesthesia, angiokeratomas, cornea verticillata and subnephrotic proteinuria. Deposits compatible with FD were detected upon renal biopsy. The evaluation of alpha-galactosidase A showed no activity in both blood and leukocytes. Genetic analysis identified an M284 T mutation in exon 6, and such mutation was also found in other family members.

Conclusion

Clinical investigation is necessary in suspected cases of Fabry Disease upon renal biopsy in order to confirm diagnosis. Drug-induced renal phospholipidosis should be considered in differential diagnosis in cases with intracellular osmiophilic, lamellar inclusions in electron microscopy.

Renal Biopsy: A much needed tool in patients with Systemic Lupus Erythematosis (SLE)

Background and Objective:

Systemic lupus erythematosis (SLE) is an inflammatory disorder associated with significant morbidity and mortality. Kidneys are frequently affected in SLE and various stages of lupus nephritis have been identified based on severity of the disease. Treatment varies with the staging and correct diagnosis is essential for timely intervention as it can have significant impact on morbidity and mortality. The objective of the study was to determine whether laboratory parameters of lupus nephritis (LN); including urinalysis, serum creatinine (S. Cr) and 24 hours urine protein can accurately predict histologic staging of the disease.

Methods:

This retrospective study was conducted in department of Nephrology, Liaquat National Hospital Karachi from January 2012 to December 2014. Fifty one patients of SLE who underwent renal biopsy were selected. Patients, urinalysis at the time of renal biopsy, serum creatinine and 24 hours urine collection for protein were noted. All patients renal biopsy was read by the same pathologist. Patients were clinically staged based on these parameters and their histologic staging based on biopsy findings were compared, to see their correlation. Data was analyzed using SPSS version 17. Chi-square test was used to analyze categorical data and p<0.05 was considered significant. Cohen’s kappa (κ) analysis was used to examine the agreement by comparing lupus nephritis staging done by laboratory and histological ground. P value <0.05 indicates that agreement was unlikely due to chance alone.

Results:

Among 51 patients analyzed, 37 patients were females (72.5%) and 14 patients were males (27.5%) with mean age of 32.51 + 16.91 years. In stage II, kappa (κ) of 0.304 represented fair strength of agreement and a p value of 0.012 (p<0.05)which was statistically significant. In stage III, kappa was 0.209 indicating none to slight agreement and a p value of 0.131 (p>0.05). In stage IV, kappa (κ) was 0.141 (slight agreement)and p value 0.301 (p>0.05) in stage V; kappa (κ) of 0.030 represented poor agreement and a p value of 0.828 (p>0.05).

Conclusion:

Staging of lupus nephritis done on basis of laboratory findings did not correlate well with underlying histological staging. Therefore, renal biopsy is an essential tool in approach to lupus nephritis in order to provide timely and appropriate treatment to patients.

An Iranian experience on renal allograft diseases

BACKGROUND

Renal transplantation is the treatment of choice for most patients with end stage renal disease. In addition, renal biopsy is the gold standard to assess the causes of renal allograft dysfunction. This study was designed to evaluate and designate renal lesions according to Banff schema.

METHODS

In this cross-sectional study, all renal allograft biopsies obtained from renal transplant patients at Alzahra and Noor referral hospitals in Isfahan during 2006-2008 were studied. Evaluations were made according to the Banff classification 2009. Clinical data was collected from the pathology database and analyzed using SPSS.

RESULTS

A total number of 161 specimens were studied from 68% male and 32% female subjects. The donor source was living unrelated in 85%, living related 9.9% and cadaveric in 5% of cases. Pathologic results showed 22.4% acute tubular necrosis (ATN), 13.7% interstitial fibrosis and tubular atrophy (IF/TA) grade II, 9.9% IF/TA (Grade III), 6.8% acute T-cell mediated rejection (TCMR-IA), 5.6% TCMR-IB, 5% borderline change, 5% infarction, 4.3% TCMR-IIA, 4.3% TA/IF (Grade I), 3.7% acute antibody-mediated rejection (ABMR), 1.9% TCMR-IIB and 17.4% other lesions.

CONCLUSIONS

The commonest causes of graft dysfunction after kidney transplant were IF/TA, no evidence of any specific etiology (NOS) and ATN. Living donors were found to be important sources for kidney transplantation in Iran.

The role of electron microscopy for the diagnosis of childhood glomerular diseases

OBJECTIVE

Optimum diagnosis of glomerulopathies requires light microscopy, immunofluorescence and electron microcopy. In fact electron microscopy has a confirmatory role in glomerular diseases. It provides more information for patient management and can rule out other diseases. The goal of the present study is analysis the necessity of electron microscopy for the diagnosis of childhood glomerulopathies.

METHODS

134 cases of renal biopsy with some clinical data retrospectively were reviewed. The contribution of electron microscopy to the final diagnosis was graded as necessary - diagnosis could not be reached without it, supportive - it increased the level of confidence in the final diagnosis and noncontributory - the diagnosis don't need electron microscopy for confirmation.

FINDINGS

The contribution of electron microscopy to the final diagnosis was necessary in 51 cases (38%), supportive in 40 cases (≅ 30%) and noncontributory in 43 cases (32%).

CONCLUSION

In conclusion the results showed in about 68% of childhood glomerulopathies the ultrastructural study was necessary or supportive, so electron microscopy still remains an important tool in diagnosis of childhood glomerulopathies.