The Clinical Course and Prognostic Factors of COVID-19 in Patients with Chronic Kidney Disease, A Study in Six Centers

INTRODUCTION

Coronavirus disease 19 (COVID-19), has recently emerged as a great health challenge. The novel corona virus may affect the kidneys mainly as acute kidney injury (AKI). Also, the outcome of COVID-19 may be different in patients with underlying kidney disease. The aim of this study was to compare the outcome of COVID-19 in patients with and without underlying kidney disease.

METHODS

This was a retrospective study on 659 hospitalized COVID-19 patients in six centers of Iran. Patients were classified into kidney (chronic kidney disease (CKD), end-stage kidney disease (ESKD) or kidney transplantation) and non-kidney groups. The clinical conditions and laboratory data were extracted from the charts. Outcome was defined as death during hospitalization or within 30 days of discharge.

RESULTS

Among 659 COVID-19 patients (mean age: 60.7 ± 16.4, 56% male), 208 were in the kidney group (86 ESKD, 35 kidney transplants, and 87 CKD patients). AKI occurred in 41.8%. Incidence of AKI was 34.7% in non-kidney, 74.7% in CKD, and 51.4% in kidney transplant patients (P < .001). Totally 178 patients (27%) died and mortality rate was significantly higher in CKD patients (50.6 vs. 23.4%, P < .001). AKI was associated with increased mortality rate (OR = 2.588, CI: 1.707 to 3.925). Initial glomerular filtration rate (GFR) < 44.2 mL/min and elevated lactate dehydrogenase (LDH) and C-reactive protein (CRP) had significant association with mortality.

CONCLUSION

We showed a higher mortality rate in COVID-19 patients with AKI and CKD. Low initial GFR and elevated LDH and CRP were associated with high mortality in COVID-19 patients.

Everolimus induced pulmonary thromboembolism after kidney transplantation; a case report

Choice of maintenance immunosuppressive therapy after renal transplantation is important for graft survival. However, complication may also occur. Venous thromboembolic event with the mTOR inhibitor (mTORi) everolimus is a rare but life-threatening complication. Here we describe a renal transplant recipient who developed pulmonary thromboembolism.

Transplant renal artery stenosis without hypertension: A case report

In kidney transplant recipients, the renal artery stenosis is cause of graft dysfunction and graft loss. Here we describe a case that leads to graft loss. The nephrologist should know about its etiologies, symptoms and diagnostic tools and also its treatment after renal transplantation.

Nephrotic Syndrome After Hematopoietic Stem Cell Transplant: Outcomes in Iran

OBJECTIVES

Patients undergoing hematopoietic stem cell transplant have an elevated incidence of acute renal failure. However, the incidence of nephritic syndrome due to graft-versus-host disease is growing and is independently associated with chronic renal disease after this procedure.

MATERIALS AND METHODS

We conducted a prospective study to examine the risk of chronic kidney disease in glomerulopathy patients following hematopoietic stem cell transplant with a follow-up of 10 years.

RESULTS

In our follow-up of 14 patients (4 men and 10 women) who were diagnosed with nephrotic syndrome after hematopoietic stem cell transplant, in 10 patients (71%), biopsy showed membranous nephropathy associated with graft-versus-host disease. The remaining 4 patients had focal segmental glomerulosclerosis, membranoproliferative glomerulonephritis, or minimal change disease. All patients were treated with angiotensin receptor blockers, cyclosporine (Neoral), and prednisolone. During follow-up, 6 patients (43%) had heavy proteinuria and a rise in serum creatinine, and 1 patient (7%) needed hemodialysis. Eleven patients (79%) achieved complete remission of nephrotic syndrome, 5 (36%) remained hypertensive, and 3 (21%) did not respond to therapy..

CONCLUSIONS

The early diagnosis of nephrotic syndrome should be considered after hematopoietic stem cell transplant, and therapeutic outcome measures should be in place in advance. If this is done, we found that patients' response to treatment can be optimal, and their renal function and overall survival can improve.

Impact of FGF23 level on calcium and phosphorus levels in post-renal transplantation

Introduction: The level of fibroblast growth factor 23 (FGF23) may be considered as a prognostic factor for assessing renal function in regulating components of phosphate and vitamin D hemostasis. Objectives: The present study aimed to evaluate the prognostic value of FGF23 level to predict renal function after renal transplantation. Patients and Methods: Fifteen consecutive patients scheduled for renal transplantation. To assess renal function status, the MDRD formula and isotope scan were applied. The study endpoint was to assess the level of FGF23 and other factors involving calcium and phosphorus metabolism before and also 3 and 12 months after transplantation and also to determine role of FGF23 to predict postoperative renal function. Results: The mean level of FGF23 was 839.51±694.56 ρg/mL at baseline that reduced to 44.31±22.01 ρg/mL and 20.13±36.50 ρg/mL, 3 and 12 months after initial assessment. The levels of FGF23 was significantly lower at 3 and 12 months after baseline (P=0.01 and P=0.02, respectively) with no difference in FGF23 level between the time points of 3 and 12 months after transplantation. Baseline level of FGF23 was found to be higher in the patients with higher glomerular filtration rate (GFR), in older patients, in males, in those patients with diabetic nephropathy, in those with acceptable renal function than in patients who suffered transplant rejection. Conclusion: The level of postoperative FGF23 is an important marker for secretion of phosphorus from kidneys emphasizing the central role of FGF23 marker to regulate calcium and phosphorus metabolism after a successful renal transplantation.

Genetic analysis of Iranian autosomal dominant polycystic kidney disease: new insight to haplotype analysis

Autosomal Dominant Polycystic Kidney Disease (ADPKD) caused by mutations in two PKD1 and PKD2 genes. Due to the complexity of the PKD1 gene, its direct mutation screening is an expensive and time-consuming procedure. Pedigree-based haplotype analysis is a useful indirect approach to identify the responsible gene in families with multiple affected individuals, before direct mutation analysis. Here, we applied this approach to investigate 15 appropriate unrelated ADPKD families, selected from 25 families, who referred for genetic counseling. Four polymorphic microsatellite markers were selected around each PKD1 and PKD2 loci. In addition, by investigating the genomic regions, two novel flanking tetranucleotide STR markers were identified. Haplotype analysis and calculating Lod score confirmed linkage to PKD1 in 9 families (60%) and to PKD2 in 2 families (13%). Linkage to both loci was excluded in one family (6.6%). In 2 families (13%) the Lod scores were inconclusive. Causative mutation was identified successfully by direct analysis in two families with confirmed linkage, one to PKD1 and another to PKD2 locus. The study showed that determining the causative locus prior to direct mutation analysis is an efficient strategy to reduce the resources required for genetic analysis of ADPKD families. This is more prominent in PKD2-linked families. Selection of suitable markers, and appropriate PCR multiplexing strategy, using fluorescent labeled primers and 3 primer system, will also add value to this approach.

The effect of treatment with N-acetylcysteine on the serum levels of C-reactive protein and interleukin-6 in patients on hemodialysis

Patients with end-stage renal disease (ESRD) are at an increased risk of cardiovascular disease due to many factors including inflammation and oxidative stress. N-acetylcysteine (NAC) is a thiol-containing anti-oxidant with anti-inflammatory properties. We aimed to assess the effect of three months treatment with oral NAC on the plasma levels of inflammatory mediators like interleukin-6 (IL-6) and C-reactive protein (hs-CRP) in patients on hemodialysis (HD). Twenty-four patients (nine males and 15 females) on maintenance HD were recruited in the study. Their mean age was 55.3 years. All the patients received oral NAC (600 mg twice a day) for a period of three months. The serum levels of biomedical parameters and IL-6 and hs-CRP were measured at baseline and three months after initiation of treatment. A significant decrease in serum levels of hs-CRP (22.4 vs. 5.2), IL-6 (8.1 vs. 3.6), parathyroid hormone (iPTH) (257.2 vs. 158.8), ferritin (632.0 vs. 515.1) and erythrocyte sedimentation rate (ESR) (54.2 vs. 38.3) was observed following NAC treatment. Female subjects presented with a significantly higher change in serum levels of hs-CRP compared with males (23 vs. 5.4). In three subjects who were less than 40 years old, the hs-CRP and IL-6 levels showed an increase following NAC treatment. Our study found that short-term oral NAC treatment might result in the reduction of IL-6 and hs-CRP in patients who are on regular HD. This suggests that patients with ESRD may benefit from the anti-inflammatory effects of NAC.

Association of overtime urine volume and ultrafiltration changes with patient survival in continuous ambulatory peritoneal dialysis patients

BACKGROUND

Associations between patient survival and baseline urine volume (UV), ultrafiltration (UF) volume, and combined UV and UF were evaluated in Iranian continuous ambulatory peritoneal dialysis (CAPD) patients.

METHODS

From 1995 to 2006, data on 1472 CAPD patients from 26 centers were collected. Demographic, clinical, and laboratory characteristics were analyzed using STATA software. Baseline UV was considered as an indicator of residual renal function and patients with an annual decrease of more than 250 cc/day were placed in decreasing UV group. The role of a new variable, net positive fluid removal, which defines as the combination of baseline UV and UF, was also evaluated.

RESULTS

Patients with higher baseline UV were significantly more married and educated and candidate for CAPD based on positive selection criteria. In dichotomous categorization, mean of serum creatinine was lower and albumin was higher in patients with UV ≥ 1000 cc/day compared with UV < 250 cc/day. A significant correlation was found between baseline UV <250 cc/day and ≥1000 cc/day and patient survival. Patients with stable UV had better survival compared with patients with decreasing UV (p = 0.04). There was no correlation between UF and patient survival. Remarkable association with patient and technique survival and net positive fluid removal ≥2000 cc/day and <500 cc/day was observed. Multiple Cox regression analysis revealed significant correlation between net positive fluid removal ≥2000 cc/day and higher patient survival [p = 0.01, hazard ratio (HR) = 13.2], higher first albumin (albumin ≥ 3.5 mg/dL, p = 0.01, HR = 0.02), and lower negative selection (p = 0.0001, HR = 11.8).

CONCLUSION

Loss of UV over time and lower net positive fluid removal increase mortality of PD patients.

Association of inflammatory biomarkers with metabolic syndrome in hemodialysis patients

The relative importance of inflammatory markers in relation with metabolic syndrome (MeS) in hemodialysis (HD) patients is uncertain. This study investigated the association between MeS and high-sensitive C-reactive protein (hsCRP), hallmark of inflammation, and other inflammatory-related biomarkers. The study included 153 patients who were dialyzed at least for the last 3 months. The serum level of hsCRP was assessed by high-sensitive Enzyme-linked immunosorbent assay (ELISA). MeS was defined using the modified National Cholesterol Education Program Adult Treatment Panel III (ATP-III). Ninety-one HD patients (59.5%) were diagnosed as having MeS. Lower level of high-density lipoprotein-cholesterol (HDL-C) was the most prevalent MeS component (85.6%). The serum level of hsCRP in these patients was significantly higher than that in HD patients without MeS (2.3 ± 1.7 vs. 1.7 ± 1.6 mg/dL, p = 0.03). A significant linear increase in the hsCRP levels was found according to the number of MeS components (β = 0.09, p = 0.022). The study concluded that increasing inflammatory biomarkers, especially hsCRP, is associated with MeS in HD patients.

Patient outcome in primary peritoneal dialysis patients versus those transferred from hemodialysis and transplantation

BACKGROUND

According to the concept of integrated care, renal transplantation, peritoneal dialysis (PD), and hemodialysis (HD) should be considered three complementary methods of renal replacement therapy. This study tried to evaluate patient outcomes in three different groups of PD patients, namely primary PD patients, those transferred to PD with failing kidney transplant, and those transferred to PD from HD.

METHOD

From January 1, 1995, to end of 2006 from 26 PD centers, 1,355 patients including demographic, clinical and laboratory data, which were monthly collected through questionnaires, were enrolled in the study. We compared patients' characteristics, factors affecting patient survival, and patient outcomes between primary PD patients (group 1, n = 1,067), patients transferred from transplantation (group 2, n = 43) and those transferred from HD (group 3, n = 245), which had been on HD for at least 3 months before switching to PD.

RESULTS

There was no difference in the proportion of patients with diabetes in the three groups. Overall, 238 patients (17.5%) were transferred to HD but there was no significant difference in PD technique survival on between the three groups. Death occurred in 256 (24%), 3 (7%) and 65 (26.5%) subjects in groups 1, 2 and 3, respectively. Most patients (81.5%) in group 2 underwent re-transplantation. The Kaplan-Meier survival rates were not different between the three groups. In the Cox multiple regression model, age, presence of diabetes and serum albumin level significantly influenced patient survival.

CONCLUSION

We concluded that PD could be considered safe for patients experiencing complications on HD, as well as for those with renal transplantation.

Low prevalence of BK virus nephropathy on nonprotocol renal biopsies in Iranian kidney transplant recipients: one center's experience and review of the literature

OBJECTIVES

BK virus-associated nephropathy in renal transplant recipients has been increasing in frequency in recent years. This rise is probably because of widespread use of highly potent immunosuppressive regimens, and increased immunosuppression load leads to inability of the recipients to increase a successful antiviral immune response. The incidence of BK virus-associated nephropathy in different reports is between 1% and 10%, with an allograft loss in significant numbers of patients, especially when timely diagnosis and treatment is not restored. We report our experience on BK virus nephropathy in our institute.

MATERIALS AND METHODS

All renal transplant biopsies performed at our center between 2001 and 2006 were immunohistochemically screened for the presence of PV-specific protein (SV40 Ag). The histologic diagnosis of BK virus-associated nephropathy was made upon the observation of morphologic changes in tubular epithelium and confirmation with immunohistochemical staining. We reviewed the clinical records of the subjects for demographic, clinical, and laboratory data.

RESULTS

BK virus nephropathy was found in 0.93% of all investigated allograft biopsies (1/108) and in 1.04% of all recipients (1/96; mean age of recipients, 36.48±14.10 years; age range, 13-74 years); 54 of them were male (57%). Type of kidney transplant was living-unrelated donor 76 (79%), living-related donor 13 (14%), and deceased donor 7. Seventeen patients (18%) were transplanted for a second time. Immunosuppressive drugs in 87 of recipients (90%) were cyclosporine, mycophenolate mofetil, and prednisolone. Our patient who developed BK virus-associated nephropathy 9 months after transplant was a 37-year-old man on prednisone, cyclosporine, and azathioprine immunosuppresion. He lost his graft 4 months after diagnosis.

CONCLUSIONS

Although BK virus nephropathy after renal transplant is uncommon, it is a serious complication causing loss of the allograft. It should be included in the clinical differential diagnosis of transplant dysfunction.

Renal involvement in patients with hepatitis C virus infection

INTRODUCTION

Hepatitis C virus (HCV) infection is a hepatotropic virus causing a variety of extrahepatic immunological manifestations and is a risk factor of a variety of extrahepatic diseases, such as mixed cryoglobulinemia and membranoproliferative glomerulonephritis (MPGN), which is the most common glomerulonephritis. The aim of this study was to evaluate renal involvement in HCV-infected patients.

MATERIALS AND METHODS

A total of 300 randomly-selected HCV antibody-positive outpatients at the HCV clinic of Shariati hospital were enrolled. Serum creatinine was measured and glomerular filtration rate was estimated accordingly. Urine proteinuria was measured in 24-hour urine samples.

RESULTS

The patients were 249 men (83.2%) and 51 women (16.8%) with a mean age of 37.8 +/- 11.7 years (range, 18 to 70 years). Proteinuria was found in 12 HCV antibody-positive adults (4%), 1 of whom underwent biopsy. He was a 55- year-old man with a 4-month history of facial and lower extremities edema and 3-g proteinuria with a normal kidney function (glomerular filtration rate, 85 mL/min) and normocomplementemia. Kidney biopsy specimens showed MPGN. The frequency of low glomerular filtration rate was 0.7% (2 patients) in the HCV antibody-positive adults. There was no significant relationship between HCV seropositivity and low glomerular filtration rate.

CONCLUSIONS

Our observations showed renal involvement in HCV antibody-positive patients. Among immune complex glomerular kidney diseases, MPGN without cryoglobulins is thought to be the most common in these patients.

Predictors of patient survival in continuous ambulatory peritoneal dialysis: 10-year experience in 2 major centers in Tehran

INTRODUCTION

Many factors have been proposed to be associated with higher mortality in patients on continuous ambulatory peritoneal dialysis (CAPD). However, the relative importance of these factors may differ among patients with different characteristics. We evaluated survival of patients on CAPD and its influencing factors in Iran.

MATERIALS AND METHODS

We enrolled 282 patients on CAPD between 1996 and 2006 at 2 major CAPD centers in Tehran. Patient survival was investigated during this period. Demographic characteristics, laboratory data, dialysis adequacy parameters, residual renal function, peritoneal transport characteristics, and nutritional status were assessed as potential predictors of the outcome.

RESULTS

The mean duration of follow-up was 18.4 +/- 14.5 months. Sixty patients (21%) died during the studied period. In univariate analysis, age, body mass index, history and duration of hemodialysis before CAPD, diabetes mellitus, blood pressure, patient selection criteria, edema, peritonitis, renal residual function, urine volume, dialysis adequacy, and serum levels of cholesterol, triglyceride, intact parathyroid hormone, calcium, and albumin were predictors of patient survival. Multivariate analysis demonstrated that old age, diabetes mellitus, prior hemodialysis longer than 7 months, low serum albumin, calcium, trigelyceride, and parathyroid hormone levels independently predicted mortality, while the use of angiotensin-converting enzyme inhibitors was associated with a better survival.

CONCLUSIONS

This study showed that older patients on CAPD and diabetics are at a higher risk of mortality. On the other hand, nutritional and metabolic factors are other predictors of mortality. Especial concern should be applied to good nutrition and treatment of comorbidities in these patients.

Frequency, risk factors, and outcome of acute kidney injury following bone marrow transplantation at Dr Shariati Hospital in Tehran

INTRODUCTION

Bone marrow transplantation (BMT) is a major modality for malignant and hematologic disorders. This procedure is associated with a high morbidity and mortality such as acute kidney injury (AKI). Many factors, such as therapeutic agents, irradiation, and graft versus host disease (GVHD) can cause AKI. Bone marrow transplantation conditioning therapy in Iran is based on drugs such as busulfan and cyclophosphamide and without irradiation therapy. The aim of this study was to evaluate the frequency, risk factors, and mortality of AKI among patients who underwent BMT.

MATERIALS AND METHODS

Acute kidney injury was defined as doubling serum creatinine from baseline at any time during the first 180 days posttransplant. The risk of AKI in relation to non-total-body-irradiation-based conditioning regimen, type of graft (allograft and autograft), comorbidities, GVHD, drug toxicity, and veno-occlusive disease were examined in 375 patients with BMT.

RESULTS

One hundred and forty-two patients (37.6%) developed AKI at a median of 18 days after transplant. A higher frequency of AKI was observed in patients who received cyclosporine A (40%), patients with allograft BMT (42.1%), and those who developed gastrointestinal GVHD (47.3%) .The remainder AKI cases were associated with amphotericin B, veno-occlusive disease, and hemolytic-uremic syndrome.

CONCLUSIONS

The frequency of AKI in our patients with BMT remained high. Cyclosporine A and amphotericin B and the presence of GVHD and veno-occlusive disease increased the risk of AKI within the first 180 days after BMT.

Association of hyperglycemia on allograft function in the early period after renal transplantation

Hyperglycemia is common following renal transplantation. This study was conducted to evaluate the relationship of perioperative serum glucose levels and acute rejection in 100 nondiabetic patients who underwent renal transplantation. Blood glucose was measured immediately following surgery and every 6 hours during the first 48 hours posttransplant as well as for 1 month to evaluate occurrence of acute rejection episodes (ARE). The rate of ARE was 33%. The mean blood glucose level immediately after surgery in patients with versus without ARE was 249.67 +/- 61.78 and 184.82 +/- 73.35 mg/dL, respectively (P=.000). There was no significant correlation between ARE and donor or recipient age or sex, delayed graft function, type of donor, or treatment. This study suggested a correlation between immediate blood glucose and ARE. In this regard, blood glucose monitoring and control during operation and immediate postoperatively may reduce the acute rejection rate.