Medullary nephrocalcinosis, distal renal tubular acidosis and polycythaemia in a patient with nephrotic syndrome

Abstract

BackgroundMedullary nephrocalcinosis and distal renal tubular acidosis are closely associated and each can lead to the other. These clinical entities are rare in patients with nephrotic syndrome and polycythaemia is an unusual finding in such patients. We describe the presence of medullary nephrocalcinosis, distal renal tubular acidosis and polycythaemia in a patient with nephrotic syndrome due to minimal change disease. Proposed mechanisms of polycythaemia in patients with nephrotic syndrome and distal renal tubular acidosis include, increased erythropoietin production and secretion of interleukin 8 which in turn stimulate erythropoiesis.Case presentationA 22 year old Sri Lankan Sinhala male with nephrotic syndrome due to minimal change disease was investigated for incidentally detected polycythaemia. Investigations revealed the presence of renal tubular acidosis type I and medullary nephrocalcinosis. Despite extensive investigation, a definite cause for polycythaemia was not found in this patient. Treatment with potassium and bicarbonate supplementation with potassium citrate led to correction of acidosis thereby avoiding the progression of nephrocalcinosis and harmful effects of chronic acidosis.ConclusionThe constellation of clinical and biochemical findings in this patient is unique but the pathogenesis of erythrocytosis is not clearly explained. The proposed mechanisms for erythrocytosis in other patients with proteinuria include increased erythropoietin secretion due to renal hypoxia and increased secretion of interleukin 8 from the kidney. This case illustrates that there may exist hitherto unknown connections between tubular and glomerular dysfunction in patients with nephrotic syndrome.

Development of Pericardial Calcification with Cortical Nephrocalcinosis in a Preterm Infant: A Case Report

“…Inevitably, these factors lead to greater stone production. Other major reasons that contribute to nephrocalcinosis may primary hyperparathyroidism, persistent renal tubular acidosis, medullary sponge kidney, hyperoxaluria (primary, enteric, or toxic), secondary to neoplasm, and drugs (furosemide and amphotericin B) [1][2][3][4][5][6]12]. Other reasons may include subacute fat necrosis, nutritional reasons (high Vitamin D or TPN), or genetic causes [8][9][10][11].…”

“…An important method of detecting nephrocalcinosis is by imaging. The best methods are by ultrasonagraphy, radiography, or computed tomography [12][13][14][15]. Axial computed tomography without contrast is considered the best method for differentiating macroscopic nephrocalcinosis and localizing calcifications [12][13][14][15].…”

“…Wings to the Research Most nephrocalcinosis findings in neonates are found incidentally by imaging. The most common methods to detect it are ultrasound, radiography, and computed tomography, which reveal calcium deposits within the renal parenchyma accompanied by variable compromised renal function [12][13][14][15]. These imaging modalities also reveal extrarenal manifestations of the underlying cause of the nephrocalcinosis with the most common being nearby retroperitoneal involvement, gastrointestinal tract, and the lungs.…”

Familial mixed nephrocalcinosis as a cause of chronic kidney failure: two case reports

“…Nephrocalcinosis is a generalized increase in the concentration of calcium and the deposition of calcium salts in the renal parenchyma [ 1 ]. The main etiological agents of this condition are primary hyperparathyroidism, renal tubular acidosis, medullary sponge kidney, idiopathic hypercalciuria, hyperoxaluria (primary, enteric or toxic), secondary hypercalcemia (sarcoidosis, neoplasm and osteoporosis) and drugs (including furosemide, acetazolamide and amphotericin B) [ 2 ].…”

“…Nephrocalcinosis can be detected by diagnostic imaging examinations (radiography, ultrasound and computed tomography) [ 1 , 4 ] which reveal calcium deposits in the renal parenchyma suggesting irreversible lesions accompanied by a variable degree of compromised kidney function [ 5 ]. The literature on familial mixed nephrocalcinosis is scarce.…”