Nephrology

Burden, access, and disparities in kidney disease Deidra C Crews, Aminu K Bello, Gamal Saadi, for the World Kidney Day Steering Committee  Indian Journal of Nephrology 2019 29(2):77-83

Persistent metabolic acidosis on regular hemodialysis or peritoneal dialysis K. T. C Goutham, KT Harichandrakumar, P Dhanin, PS Priyamvada, S Haridasan, S Parameswaran Indian Journal of Nephrology 2019 29(2):84-89 Metabolic acidosis is known to have adverse consequences in patients with chronic kidney disease (CKD) including protein-energy wasting, inflammation, bone disease, and disturbance in endocrine function. Unlike in the management of patients with predialysis CKD, bicarbonate levels were not being routinely monitored in dialysis patients at our center. The KDOQI guidelines recommend serum bicarbonate levels ≥22 mEq/L in patients on dialysis. We measured the predialysis serum bicarbonate levels in 100 adult patients on regular hemodialysis (HD) and 41 adult patients on peritoneal dialysis (PD). We also studied the extent of rise in serum bicarbonate levels from predialysis levels after HD in our patients. Predialysis serum bicarbonate level was <22 mEq/L in 73% of patients on HD and 12% of patients on PD. The serum bicarbonate levels remained <22 mEq/L at the end of HD in 41% of patients on HD. Thirty-nine percent of patients were on a HD schedule of thrice a week, and 93% of PD patients performed three PD exchanges a day. The dialysate bicarbonate level was 34 mEq/L. There was a significant increase in serum bicarbonate levels with HD, but the mean postdialysis bicarbonate level was 23.45 mEq/L. A very high proportion of our patients on HD continued to have uncorrected metabolic acidosis, with metabolic acidosis persisting in the immediate postdialysis period in a significant number of patients. Predialysis serum bicarbonate level needs to be monitored in patients on HD. There is an urgent need to modify HD prescription to ensure better correction of metabolic acidosis in our HD population. Compared to HD, the proportion of patients having persistent metabolic acidosis is significantly lower in PD.

Loss of subpodocytic space predicts poor response to tacrolimus in steroid-resistant calcineurin inhibitor-naïve adult-onset primary focal segmental glomerulosclerosis P Agrawal, R Nada, R Ramachandran, CS Rayat, A Kumar, HS Kohli Indian Journal of Nephrology 2019 29(2):90-94 Focal segmental glomerulosclerosis (FSGS) is the most common cause of adult-onset nephrotic syndrome, but its pathophysiology is poorly understood. The question as to why only a subset of patients responds to treatment in unanswered. In the past few years, change of podocytic phenotype from stationary type in health to migratory type in disease has been described, of which loss of subpodocytic space is a surrogate marker. Diagnostic biopsies of adult-onset steroid-resistant calcineurin inhibitor-naïve primary FSGS cases, which were subsequently treated with tacrolimus were included in this retrospective study conducted from 2011 to 2013. The ultrastructure of all cases was studied in detail, especially in context to the presence or absence of subpodocytic space. In the present study, we have compared presence or absence of subpodocytic space in tacrolimus-responsive versus tacrolimus-resistant cases to identify potential electron microscopic features predictive of response to treatment, of which loss of subpodocytic space indicating migratory phenotype is the most important and consistent feature. The present series included 7 tacrolimus responsive cases (includes two cases with partial response) and seven tacrolimus-resistant cases. The tacrolimus-resistant patients were of older age, had a longer duration of illness, and a lower eGFR as compared to tacrolimus responsive cases. The subpodocytic space was preserved in patients on tacrolimus with complete remission and lost in patients with partial response and tacrolimus-resistant cases.

Pulmonary hypertension in various stages of chronic kidney disease in Indian patients Kalpana S Mehta, Abhishek K Shirkande, Sandip P Bhurke, Atim E Pajai, Rudramani S Swami, Swapnil N Jadhav Indian Journal of Nephrology 2019 29(2):95-101 The prevalence of pulmonary hypertension (PH) in chronic kidney disease (CKD) in Indian patients has been evaluated in this study. In addition, association of PH with CKD etiology, its prevalence in various CKD stages, correlation between the severity of PH with CKD duration, various related biochemical parameters, and their relation to PH in CKD patients were analyzed. This cross-sectional and prospective study included 200 CKD patients. Detailed history and clinical examination were recorded. Hemoglobin, blood urea nitrogen (BUN), serum creatinine, albumin, and calcium-phosphorus product were recorded. Pulmonary function test was evaluated and two-dimensional echo was done 4 hours post dialysis. The prevalence of PH in CKD patients was 60.5%, with mean pulmonary artery systolic pressure (PASP) of 38.52 ± 7.32 mmHg. The mean age of those with PH was 47.85 ± 13.09 years. PH was more common in males (p = 0.03). The prevalence of PH increased as CKD stage advanced (p < 0.001). Diabetes and hypertension had a strong association with PH (p < 0.001). The prevalence (p = 0.003) and severity (p = 0.011) of PH increased with increase in CKD duration. In patients on hemodialysis (HD), the prevalence (p < 0.001) and severity (p = 0.022) of PH was significant compared to those on conservative treatment. The prevalence (p < 0.001) and severity (p < 0.001) of PH significantly increased as duration of HD increased. The prevalence of PH was significantly higher in patients with arteriovenous fistula (p = 0.002). Serum creatinine (p = 0.02) and serum calcium-phosphorus product (p < 0.001) were significantly higher in patients with PH. The prevalence of PH in CKD patients was 60.5%. There was a positive correlation between PH and duration of CKD, duration of HD, BUN, serum creatinine, and serum calcium-phosphorus product.

Volume assessment in hemodialysis: A comparison of present methods in clinical practice with sonographic lung comets Ishwarya Annamalai, Suhasini Balasubramaniam, M Edwin Fernando, ND Srinivasaprasad, S Suren, K Thirumalvalavan, AM Veerakumar Indian Journal of Nephrology 2019 29(2):102-110 Dry weight assessment in dialysis patients remains a challenging endeavor owing to the limitations of the available methods for volume assessment. Lung ultrasound is emerging as an invaluable tool to assist in the appropriate assessment and assignment of dry weight. The objectives of this study are (1) to determine the reliability of clinical signs and symptoms for volume assessment, (2) to compare lung ultrasound with High Resolution Computed Tomography (HRCT) chest-A noninvasive gold standard tool for detecting pulmonary congestion and with inferior vena cava diameter (IVCD) – another time-tested volume assessment method, and (3) to analyze if lung ultrasound could detect dialysis induced fluid status variations. The cross-sectional study involves 50 patients on maintenance hemodialysis. Lung ultrasound for B line estimation and ultrasonographic measurement of IVCD performed before and after hemodialysis by a nephrologist trained in ultrasonography. Limited HRCT was obtained just before hemodialysis. Edema, crackles, and dyspnea had a poor sensitivity of 37.9%, 11.5%, and 52.6%, respectively, to detect clinically significant pulmonary congestion by lung ultrasound. A highly significant correlation was obtained between B-line score and HRCT signs of pulmonary congestion (P < 0.001) before dialysis. B lines showed statistically significant reduction with dialysis. The absolute reduction of B lines showed significant correlation with ultrafiltration volume and weight loss. Bedside lung ultrasound appears a sensitive tool for evaluating real-time changes in extravascular lung water and would serve to optimize volume status in dialysis patients.

Clinicopathological spectrum of xanthogranulomatous pyelonephritis R Kundu, A Baliyan, H Dhingra, V Bhalla, RS Punia Indian Journal of Nephrology 2019 29(2):111-115 Xanthogranulomatous pyelonephritis (XGP) is an uncommon and distinct type of chronic infective pyelonephritis causing destruction of the kidney, severely affecting the renal function. The perinephric adipose tissue and peritoneum is not uncommonly involved. The study was undertaken to decipher the clinicopathologic spectrum of XGP. Forty cases of XGP were diagnosed on histopathology over a period of 13 years (2005–2017). Relevant clinical details and radiological findings were recorded from the case files. Out of a total of 40 cases, 26 were female and 14 were male with a mean age of 39.5 ± 13.6 years. Flank pain was the most common presenting symptom. All the patients had unilateral disease and underwent nephrectomy for a nonfunctional kidney. Gross examination showed enlarged kidney with replacement of cortico-medullary tissue by yellow nodular areas of fatty tissue and dilatation of the pelvicalyceal system. Thirty-six (90%) cases had nephrolithiasis. Histologically, the characteristic feature was the existence of lipid-laden foamy macrophages. Renal parenchymal involvement was diffuse in majority (31, 77.5%). Two (5.0%) of the patients had coexisting carcinoma in the same kidney. Histopathologic examination gives the definitive diagnosis of XGP which relies on the characteristic morphology. Surgical intervention in the form of nephrectomy is the treatment of choice and offers good treatment outcomes.

Post-renal transplant metabolic acidosis: A neglected entity ME Fernando, J Jayanivash, ND Srinivasaprasad, S Suren, K Thirumalvalavan Indian Journal of Nephrology 2019 29(2):116-121 Metabolic acidosis is a prevalent yet overlooked entity among renal transplant recipients (RTRs) and incurs adverse effects on graft function. Although graft dysfunction and calcineurin inhibitor usage have been linked with renal tubular acidosis (RTA), there is no Indian data on prevalence or risk factors of post-transplant acidosis. A cross-sectional study was conducted on 106 adult RTRs, with a transplant duration of >6 months and an estimated glomerular filtration rate (GFR) >40 ml/min/1.73 m2. Acidosis was diagnosed on basis of plasma bicarbonate and arterial pH. Serum and urine electrolytes with anion gap were determined to diagnose and type RTA. Acidosis was diagnosed in 44 of 106 patients (41.5%) with 23 (52.27%) having severe acidosis. Type I RTA was the most common subtype (52.5%) followed by type IV (30.9%) and type II RTA (7.5%). The correlation between estimated glomerular filtration rate and acidosis was minimally linear (r = 0.1088), with multivariate analysis revealing previous acute rejection episodes, current serum tacrolimus levels, cotrimoxazole usage and intake of animal proteins to be independent risk factors. The serum albumin levels were low in the acidosis group and showed linear correlation with bicarbonate levels (r = 0.298). There is a high prevalence of metabolic acidosis in RTRs with type I RTA being most common subtype. Screening of RTRs on a regular basis is a feasible approach for early diagnosis and intervention. However, prospective studies are needed to demonstrate the effect of acidosis on graft survival and benefit of bicarbonate therapy in RTRs.

Cytomegalovirus induced collapsing glomerulopathy and necrotizing glomerulonephritis in a renal allograft recipient K. S. J Prema, N. D. S Prasad, AA Kurien Indian Journal of Nephrology 2019 29(2):122-124 In renal allograft recipients, cytomegalovirus (CMV) typically causes tubulointerstitial nephritis. Only rarely glomeruli are involved. We present a rare case of CMV with collapsing glomerulopathy, necrotizing glomerulonephritis, and crescent formation in a renal allograft recipient. Immunohistochemistry confirmed CMV infection. The patient was started on valganciclovir and his renal function remained stable. A repeat renal biopsy performed three months later showed morphologically normal glomeruli and CMV immunostaining was also negative. Nephropathologists have to carefully screen for CMV in cases with crescentic or collapsing glomerulopathy as the later lesions resolve after treating the underlying viral infection. This study will add on to the various glomerular changes associated with CMV infection.

C1q nephropathy in a patient of neurofibromatosis type 1: A rare case report UT Varyani, NM Shah, PR Shah, VB Kute, MR Balwani, HL Trivedi Indian Journal of Nephrology 2019 29(2):125-127 C1q nephropathy is a rare glomerular disease defined by the presence of characteristic mesangial dominant or codominant C1q deposition on immunofluorescence microscopy. Neurofibromatosis type 1 (NF-1) is an autosomal dominant syndrome caused by a mutation of a gene located on chromosomal segment 17q11.2. Nephrotic syndrome has rarely been reported in patients of NF-1, and the relation of NF-1 with nephrotic syndrome is unclear. Here, we present a rare case of C1q nephropathy in a patient of NF-1.

Pulmonary calcifications: Is it an entity in the new world dialysis patient? R Kauntia, V Bhargava, P Gupta, DS Rana Indian Journal of Nephrology 2019 29(2):128-131 Metastatic pulmonary calcification (MPC) has been described in the literature to affect up to 60% of dialysis patients. Several case series of MPC were described in 1960s and 1970s. Patients are generally asymptomatic or may present with acute respiratory distress. This entity is associated with up to 60% mortality. We hereby report a case of chronic kidney disease on maintenance hemodialysis who presented with unexplained recurrent dyspnea despite adequate hemodialysis. She was evaluated and found to have a rare presentation of calciphylaxis.