[Show abstract][Hide abstract] ABSTRACT: Background
To determine the effect of statins on renal hemodynamics in normal volunteers and those with autosomal dominant polycystic kidney disease either with mild or moderate renal dysfunction.
Thirty-two study subjects were enrolled in this study: 11 normal volunteers, 11 study subjects with autosomal dominant polycystic kidney disease (ADPKD) and mild kidney disease and 10 study subjects with ADPKD and moderate kidney disease. Subjects in each group received simvastatin 40 mg once daily for a period of 4 weeks. Renal blood flow was measured based on para-amino-hippurate (PAH) clearance and with the use of a magnetic resonance (MR) scanner at the beginning and following 4 weeks of therapy with statins.
At the end of the study, except for the lipid profile, which was significantly lower in all groups, other laboratory results showed no change. Four weeks of therapy with simvastatin resulted in no change in serum creatinine, 24-h urinary protein, sodium, iothalamate clearance, PAH clearance or renal blood flow as measured by MRI or based on PAH clearance.
Four weeks of therapy with simvastatin did not change renal blood flow in the study subjects with ADPKD with mild-to-moderate renal dysfunction or in healthy volunteers.
Clinical Trial Registration Number
Full-text · Article · Nov 2015 · Nephrology Dialysis Transplantation
[Show abstract][Hide abstract] ABSTRACT: Lactic acidosis is associated with high morbidity and mortality in hospitalized patients. Treatment of lactic acidosis is
targeted on correcting the underlying causes and optimizing adequate oxygen delivery to the tissues. Even though evidence
is lacking, continuous renal replacement therapy (CRRT) and dialysis have been advocated as treatments for lactic acidosis.
We report a 28-year-old Caucasian male with a history of hemophagocytic lymphohistiocytosis who presented with septic shock,
severe lactic acidosis and multiple organ failure. Metabolic acidosis was corrected after bicarbonate therapy and CRRT with
a hemofiltration rate of 7 L/h (58 mL/kg/h). Lactate clearance was calculated to be 79 mL/min. Compared with reported rates
of lactate overproduction in septic shock, the rate of lactate clearance is quite small. Our case suggests that CRRT with
high-volume hemofiltration is not effective for severe lactic acidosis. Lactic acidosis alone should not be considered as
a nonrenal indication for CRRT.
[Show abstract][Hide abstract] ABSTRACT: Acute interstitial nephritis (AIN) presents with acute kidney injury, with evidence of interstitial inflammation and tubulitis on histology, and the presence of fever, rash, and eosinophiluria. Although the pathogenesis of this disease is not well understood, cell-mediated immunity is thought to play a major role. We hypothesized that IgE mediated mast cell activation is also involved in the pathogenesis of renal injury in AIN.
28 patients, with biopsy proven AIN over a 5-year period, were included in this study. Clinical data, including renal outcomes and the etiologies of AIN, were evaluated in all patients. Available tissues (renal biopsy) from 26 of the patients were stained for β-tryptase (marker for mast cell degranulation), IgE, IL-16, and CD3. A negative control for immunostaining was included.
Samples from all 26 individuals stained positive for β-tryptase (mean of 11.16 cells/high power field), IgE (mean average of 0.68 cells/HPF), IL-16 (28% of the interstitium), and CD3 (33% of the interstitium). Acute interstitial nephritis was due to medication in 73%, systemic disease in 15%, and unknown (idiopathic) in 12% of the cases. 86% of patients were treated with corticosteroids. 18% required acute inpatient dialysis, with 7% remaining on dialysis longterm.
Our study suggests that IgE and mast cell activation may play a role in the pathogenesis of AIN.
No preview · Article · Jul 2015 · Clinical nephrology
[Show abstract][Hide abstract] ABSTRACT: In some patients with light chain deposition disease (LCDD) there is also evidence of myeloma cast nephropathy (MCN) on renal biopsy. The purpose of this study was to evaluate the renal and survival outcome of patients with concomitant diagnosis of MCN and LCDD to LCDD and MCN alone. Eighty seven patients were identified and divided into LCDD (n=45), MCN (n=29), and LCDD+MCN (n=13). Patients with LCDD+MCN had a worse overall survival (OS) compared to patients with LCDD (P=0.03), but similar to patients with MCN (P=0.4). Death-censored renal survival was no different amongst the groups. Presenting with acute renal failure at time of renal biopsy (HR 7.2, P=0.0002) was an independent poor renal prognostic factor while older age (HR 1.06, P=0.0002), presence of osteolytic lesions (HR 4.4, P<0.0001), and requirement for dialysis or creatinine ≥5mg/dL (HR 3.2, P=0.0006) at time of renal biopsy were independent poor prognostic factors for OS.
[Show abstract][Hide abstract] ABSTRACT: Abstract Objectives: To determine whether autosomal dominant polycystic kidney disease (ADPKD) is associated with adverse fetal outcomes and maternal complications. Methods: We identified a cohort of 146 patients seen for pregnancy and cystic kidney disease at Mayo Clinic from 1975 to 2010. From this cohort, 54 patients met the ultrasound diagnostic criteria for ADPKD (ADPKD group), while the other 92 patients were diagnosed as "Simple Cyst" (control group). We compared the fetal and maternal outcomes of pregnancy and long-term maternal prognoses between these two groups. Results: Overall, the fetal complication rates were similar between the ADPKD and control groups. Rates of spontaneous abortion (15.1% versus 14%, p = 0.77) and premature birth (11.1% versus 6.8%, p = 0.44) were comparable between groups, while the rate of fetal distress (3.4% versus 0.7%, p < 0.01) was increased in the ADPKD group. The rate of preeclampsia in the patients with simple cysts (2%) was similar to that of the general population. In contrast, the pregnant ADPKD patients had higher risks for hypertension, proteinuria, edema, urinary tract infection, renal dysfunction and preeclampsia during their pregnancies. Conclusion: ADPKD is associated with increased maternal complications during pregnancy, but only has a slight potential of increased rates of fetal complications.
No preview · Article · Mar 2015 · Journal of Maternal-Fetal and Neonatal Medicine
[Show abstract][Hide abstract] ABSTRACT: Primary focal segmental glomerulosclerosis (FSGS) is a common glomerular disease in adults and ranks among the top causes of a primary glomerular disease causing end-stage renal disease (ESRD). Primary FSGS is, however, a diagnosis of exclusion and distinction between primary versus secondary FSGS is not always obvious, resulting in a number of patients with secondary FSGS undergoing unnecessary immunosuppressive therapy.
We reviewed the Mayo Clinic Renal Pathology Database for patients with a diagnosis of FSGS on native renal biopsy and divided the patients into nephrotic syndrome-associated (NS-associated) and non-nephrotic syndrome-associated (NNS-associated) FSGS as a first approximation followed by dividing the lesion according to the degree of foot process effacement (FPE) on electron microscopy (EM) examination.
A total of 41 patients with FSGS with complete evaluation were identified. Of these, 18 were classified as having NS and 23 were classified as having NNS. Baseline characteristics (age, gender, body mass index, serum creatinine and hematuria) were not different between the groups. All of the patients with NS showed diffuse FPE ranging from 80 to 100% (mean 96%). On the other hand, of the 23 patients in the NNS group, 22 had segmental FPE and showed patchy effacement, with all cases showing 20-60% FPE (mean of 48%).
Adult patients presenting with NS, an FSGS lesion on LM, extensive FPE (≥80%) on EM examination and no risk factors associated with secondary FSGS are likely to have primary FSGS. Conversely, the absence of NS in a patient with segmental FPE on EM strongly suggests a secondary FSGS. Dividing FSGS into the presence or absence of NS together with the degree of FPE on EM examination is more helpful as it provides a more practical way to separate patients into cases of primary versus secondary FSGS.
[Show abstract][Hide abstract] ABSTRACT: Kidney International aims to inform the renal researcher and practicing nephrologists on all aspects of renal research. Clinical and basic renal research, commentaries, The Renal Consult, Nephrology sans Frontieres, minireviews, reviews, Nephrology Images, Journal Club. Published weekly online and twice a month in print.
No preview · Article · Jun 2014 · Kidney International
[Show abstract][Hide abstract] ABSTRACT: Polycystin 1 and 2, the protein abnormalities associated with autosomal dominant polycystic kidney disease (ADPKD), are also found in airway cilia and smooth muscle cells. There is evidence of increased radiologic bronchiectasis associated with ADPKD, though the clinical and functional implications of this association are unknown. We hypothesized an increased prevalence of both radiologic and clinical bronchiectasis is associated with APDKD as compared to non-ADPKD chronic kidney disease (CKD) controls.
A retrospective case-control study was performed at our institution involving consecutive ADPKD and non-ADPKD chronic kidney disease (CKD) patients seen over a 13 year period with both chest CT and PFT. CTs were independently reviewed by two blinded thoracic radiologists. Manually collected clinical data included symptoms, smoker status, transplant history, and PFT findings.
Ninety-two ADPKD and 95 non-ADPKD CKD control patients were compared. Increased prevalence of radiologic bronchiectasis, predominantly mild lower lobe disease, was found in ADPKD patients compared to CKD control (19 vs. 9%, P = 0.032, OR 2.49 (CI 1.1-5.8)). After adjustment for covariates, ADPKD was associated with increased risk of radiologic bronchiectasis (OR 2.78 (CI 1.16-7.12)). Symptomatic bronchiectasis occurred in approximately a third of ADPKD patients with radiologic disease. Smoking was associated with increased radiologic bronchiectasis in ADPKD patients (OR 3.59, CI 1.23-12.1).
Radiological bronchiectasis is increased in patients with ADPKD particularly those with smoking history as compared to non-ADPKD CKD controls. A third of such patients have symptomatic disease. Bronchiectasis should be considered in the differential in ADPKD patients with respiratory symptoms and smoking history.
[Show abstract][Hide abstract] ABSTRACT: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a small-vessel vasculitis that primarily comprises 2 clinical syndromes: granulomatosis with polyangiitis and microscopic polyangiitis. Cyclophosphamide and glucocorticoids have traditionally been used for induction of remission. However, more recent studies have shown that rituximab is as effective as cyclophosphamide for induction therapy in patients with newly diagnosed severe AAV and superior for patients with relapsing AAV. There is also accumulating evidence indicating a potential role of rituximab for maintenance therapy in AAV. In this article, we will review the evidence supporting the various treatment choices for patients with AAV.
Full-text · Article · Mar 2014 · Advances in chronic kidney disease
[Show abstract][Hide abstract] ABSTRACT: Membranoproliferative glomerulonephritis (MPGN) has been classified based on its pathogenesis into immune complex-mediated and complement-mediated MPGN. The immune complex-mediated type is secondary to chronic infections, autoimmune diseases or monoclonal gammopathy. There is a paucity of data on MPGN associated with autoimmune diseases. We reviewed the Mayo Clinic database over a 10-year period and identified 12 patients with MPGN associated with autoimmune diseases, after exclusion of systemic lupus erythematosus. The autoimmune diseases included rheumatoid arthritis, primary Sjögren's syndrome, undifferentiated connective tissue disease, primary sclerosing cholangitis and Graves' disease. Nine of the 12 patients were female, and the mean age was 57.9 years. C4 levels were decreased in nine of 12 patients tested. The serum creatinine at time of renal biopsy was 2.2 ± 1.0 mg/dl and the urinary protein was 2,850 ± 3,543 mg/24 h. Three patients required dialysis at the time of renal biopsy. Renal biopsy showed an MPGN in all cases, with features of cryoglobulins in six cases; immunoglobulin (Ig)M was the dominant Ig, and both subendothelial and mesangial electron dense deposits were noted. Median follow-up was 10.9 months. Serum creatinine and proteinuria improved to 1.6 ± 0.8 mg/dl and 428 ± 677 mg/24 h, respectively, except in 3 patients with end-stage renal disease. In summary, this study describes the clinical features, renal biopsy findings, laboratory evaluation, treatment and prognosis of MPGN associated with autoimmune diseases.
Full-text · Article · Feb 2014 · Journal of nephrology
[Show abstract][Hide abstract] ABSTRACT: C3 glomerulonephritis (C3GN) results from abnormalities in the alternative pathway of complement, and it is characterized by deposition of C3 with absent or scant Ig deposition. In many patients, C3GN progresses to ESRD. The clinical features, pathology, and outcomes of patients with C3GN receiving kidney transplantation are unknown. Between 1996 and 2010, we identified 21 patients at our institution who received a kidney transplant because of ESRD from C3GN. The median age at the time of initial diagnosis of C3GN at kidney biopsy was 20.8 years. The median time from native kidney biopsy to dialysis or transplantation was 42.3 months. Of 21 patients, 14 (66.7%) patients developed recurrent C3GN in the allograft. The median time to recurrence of disease was 28 months. Graft failure occurred in 50% of patients with recurrent C3GN, with a median time of 77 months to graft failure post-transplantation. The remaining 50% of patients had functioning grafts, with a median follow-up of 73.9 months. The majority of patients had hematuria and proteinuria at time of recurrence. Three (21%) patients were positive for monoclonal gammopathy and had a faster rate of recurrence and graft loss. Kidney biopsy at the time of recurrence showed mesangial proliferative GN in eight patients and membranoproliferative GN in six patients. All allograft kidney biopsies showed bright C3 staining (2-3+), with six biopsies also showing trace/1+ staining for IgM and/or IgG. To summarize, C3GN recurs in 66.7% of patients, and one half of the patients experience graft failure caused by recurrence.
Full-text · Article · Dec 2013 · Journal of the American Society of Nephrology
[Show abstract][Hide abstract] ABSTRACT: Background:
Recently, serum soluble urokinase receptor (suPAR) has been proposed as a cause of two thirds of cases of focal segmental glomerulosclerosis (FSGS). It was noted to be uniquely elevated in cases of primary FSGS, with higher levels noted in cases that recurred after transplantation. It is also suggested as a possible target and marker of therapy.
We studied serum and urine suPAR from pretransplantation banked samples from 86 well-characterized kidney transplant recipients and 10 healthy controls to determine its prognostic utility. Causes of native kidney disease were primary FSGS, diabetic nephropathy, membranous nephropathy, immunoglobulin A nephropathy, and autosomal dominant polycystic kidney disease. suPAR was measured using a commercially available enzyme-linked immunosorbent assay kit. Urinary suPAR was indexed to creatinine.
Both serum and urine suPAR correlated with proteinuria and albuminuria. Serum suPAR was found to be elevated in all transplant candidates with advanced renal disease compared with healthy controls and could not differentiate disease diagnosis. Urine suPAR was elevated in cases of recurrent FSGS compared with all other causes of end-stage renal disease. Recurrent FSGS cases had substantially higher proteinuria compared with all other cases. However, elevated urinary suPAR showed a trend in providing additional prognostic information beyond proteinuria in the small cohort of recurrent FSGS cases.
In advanced renal disease, elevated serum suPAR is not unique to FSGS cases. Urinary suPAR appears to be higher in cases of FSGS destined for recurrence and merits further evaluation.
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: C3 glomerulonephritis (GN) is a proliferative GN resulting from glomerular deposition of complement factors due to dysregulation of the alternative pathway of complement. Dysregulation of the alternative pathway of complement may occur as a result of mutations or functional inhibition of complement-regulating proteins. Functional inhibition of the complement-regulating proteins may result from a monoclonal gammopathy. STUDY DESIGN: Case series. SETTING & PARTICIPANTS: 32 Mayo Clinic patients with C3 GN, 10 (31%) of whom had evidence of a monoclonal immunoglobulin in serum. OUTCOMES: Clinical features, hematologic and bone marrow biopsy findings, kidney biopsy findings, kidney measures, complement pathway abnormalities, treatment, and follow-up of patients with C3 GN that was associated with a monoclonal gammopathy. RESULTS: Mean age of patients with C3 GN associated with monoclonal gammopathy was 54.5 years. Bone marrow biopsy done in 9 patients revealed monoclonal gammopathy of undetermined significance in 5 patients, small lymphocytic lymphoma/chronic lymphocytic leukemia in one patient, and no abnormal clones in the other 3 patients. Kidney biopsy showed membranoproliferative GN with bright capillary wall C3 staining in all 10 patients. Evaluation of the alternative pathway of complement showed abnormalities in 7 of 9 patients tested. No mutation in complement-regulating proteins was detected in any patient. As an index case, one patient with C3 GN and chronic lymphocytic leukemia was treated with rituximab, cyclophosphamide, vincristine, and prednisone, and one patient with C3 GN and monoclonal gammopathy of undetermined significance was treated with dexamethasone and bortezomib. Both patients showed significant decreases in hematuria and proteinuria and stabilization of kidney function. LIMITATIONS: Studies to show evidence of direct activation of the alternative pathway by monoclonal immunoglobulin were not done. CONCLUSIONS: The study highlights the association of C3 GN and monoclonal gammopathy, in particular in the older population, and the importance of targeting the underlying hematologic malignancy as an approach to treating C3 GN.
No preview · Article · Apr 2013 · American Journal of Kidney Diseases
[Show abstract][Hide abstract] ABSTRACT: Kidney perfusion can be acutely compromised by many factors including reduced systemic blood pressure and elevated intra-abdominal pressure. We present a case of near complete absence of kidney perfusion in a 57-year-old man with heart failure and new onset ascites. The renal perfusion defect was directly detected by Doppler ultrasonography. Immediate decompression with large-volume paracentesis restored the kidney perfusion and kidney function. This case illustrates that renal ultrasonography with Doppler flow analysis in appropriate settings can serve as an important adjunct in the diagnosis and treatment of acute oligoanuric kidney failure. Timely reversal of the perfusion defect can rescue kidney function.
No preview · Article · Dec 2012 · Clinical nephrology
[Show abstract][Hide abstract] ABSTRACT: Postinfectious glomerulonephritis is a common disorder that develops following an infection. In the majority of cases, there is complete recovery of renal function within a few days to weeks following resolution of the infection. In a small percentage of patients, however, the glomerulonephritis takes longer to resolve, resulting in persistent hematuria and proteinuria, or even progression to end-stage kidney disease. In some cases of persistent hematuria and proteinuria, kidney biopsies show findings of a postinfectious glomerulonephritis even in the absence of any evidence of a preceding infection. The cause of such 'atypical' postinfectious glomerulonephritis, with or without evidence of preceding infection, is unknown. Here we show that most patients diagnosed with this 'atypical' postinfectious glomerulonephritis have an underlying defect in the regulation of the alternative pathway of complement. These defects include mutations in complement-regulating proteins and antibodies to the C3 convertase known as C3 nephritic factors. As a result, the activated alternative pathway is not brought under control even after resolution of the infection. Hence, the sequela is continual glomerular deposition of complement factors with resultant inflammation and development of an 'atypical' postinfectious glomerulonephritis.Kidney International advance online publication, 12 December 2012; doi:10.1038/ki.2012.384.
Full-text · Article · Dec 2012 · Kidney International
[Show abstract][Hide abstract] ABSTRACT: Anion gap metabolic acidosis (AGMA) is commonly encountered in medical practice. Acetaminophen-induced AGMA is, however, not widely recognized. We report 2 cases of high anion gap metabolic acidosis secondary to 5-oxoproline accumulation resulting from acetaminophen consumption: the first case caused by acute one-time ingestion of large quantities of acetaminophen and the second case caused by chronic repeated ingestion in a patient with chronic liver disease. Recognition of this entity facilitated timely diagnosis and effective treatment. Given acetaminophen is commonly used over the counter medication, increased recognition of this adverse effect is of important clinical significance.
No preview · Article · Sep 2012 · The American Journal of the Medical Sciences
[Show abstract][Hide abstract] ABSTRACT: C3 glomerulonephritis (C3GN) is a recently described disorder that typically results from abnormalities in the alternative pathway (AP) of complement. Here, we describe the clinical features, kidney biopsy findings, AP abnormalities, glomerular proteomic profile, and follow-up in 12 cases of C3GN. This disorder equally affected all ages, both genders, and typically presented with hematuria and proteinuria. In both the short and long term, renal function remained stable in the majority of patients with native kidney disease. In two patients, C3GN recurred within 1 year of transplantation and resulted in a decline in allograft function. Kidney biopsy mainly showed a membranoproliferative pattern, although both mesangial proliferative and diffuse endocapillary proliferative glomerulonephritis were noted. AP abnormalities were heterogeneous, both acquired and genetic. The most common acquired abnormality was the presence of C3 nephritic factors, while the most common genetic finding was the presence of H402 and V62 alleles of Factor H. In addition to these risk factors, other abnormalities included Factor H autoantibodies and mutations in CFH, CFI, and CFHR genes. Laser dissection and mass spectrometry of glomeruli from patients with C3GN showed accumulation of AP and terminal complement complex proteins. Thus, C3GN results from diverse abnormalities of the alternative complement pathway leading to subsequent glomerular injury.
Full-text · Article · Jun 2012 · Kidney International