Radiography
Findings
Radiograph depicting bilateral nephrocalcinosis in an adult male patient who initially presented with features of pancreatitis. Ultimately, hyperparathyroidism was diagnosed. Note the mesenteric nodal calcification just below the level of left kidney.
Radiograph depicting kidneys with bilateral pyramidal calcification, which is consistent with nephrocalcinosis, most likely hyperparathyroidism (same patient as in Images 3-4 in Multimedia).
Radiograph of both hands in a patient who also has bilateral pyramidal calcification (same patient as in Images 3-4 in Multimedia). This image shows bilateral subperiosteal resorption along the radial aspect of middle phalanx. This finding is consistent with hyperparathyroidism.
Excretory urogram obtained at 15 minutes in a man with renal papillary necrosis, most likely a patient with diabetes mellitus and repeated urinary tract infections (same patient as in Images 6-7 in Multimedia). This image shows bilateral hydronephrosis and a hydroureter due to obstruction by sloughed papillae at the lower end of the ureter.
Plain kidney, ureters, and bladder (KUB) radiograph in a man with renal papillary necrosis, most likely a patient with diabetes mellitus and repeated urinary tract infections (same patient as in Images 6-7 in Multimedia). This image shows bilateral renal calcification. A large, sloughed, and calcified renal papilla is present in the region of left vesicoureteric junction. Note the 2 pelvic phleboliths opposite the ischial spine on the right.
Plain abdominal radiograph in a 40-year-old man (same patient as in Images 8-9 in Multimedia). This image shows extensive calculus formation in a medullary sponge kidney.
Radiograph from an intravenous urographic series in a 40-year-old man (same patient as in Images 8-9 in Multimedia). The image was obtained after contrast injection and shows contrast-agent accumulation in the collecting tubules in a medullary sponge kidney.
Plain radiographic detection is not possible until the attenuation of renal parenchyma exceeds 100 HU. The calcification resolution also depends on the size of the stones (those <2 mm are rarely detected), the spatial resolution of the recoding technique, and contrast factors. The characteristic cortical calcification occurs within a few weeks after the onset of acute cortical necrosis. When cortical nephrocalcinosis first appears, the kidneys are still enlarged because of inflammatory edema of the kidneys. With time, the kidneys atrophy.
Morphologically, 3 types of calcification have been described. The most prevalent is a single cortical, calcified, and thin peripheral band, often with calcified extensions into the necrotic septa of Bertin (placed perpendicular to the cortical calcification). The medullary pyramids are usually spared, retaining the attenuation of the soft tissue. Initially, this pattern of nephrocalcinosis may be difficult to recognize because the calcification is faint. However, the kidney margins appear both well defined and penciled in.
The second pattern seen with cortical nephrocalcinosis is the appearance of hyperattenuating tram lines. These lines may be continuous, but more often, they are interrupted, reflecting the more patchy distribution of cortical necrosis.
The third pattern is a more diffuse distribution of punctate calcification. This punctate pattern of calcification is thought to represent necrotic calcified glomeruli and tubules.
Medullary nephrocalcinosis typically produces clusters of stippled calcifications, mainly within the regions of the renal pyramids.
Most conditions that cause medullary nephrocalcinosis can also result in nephrolithiasis. Some nephroliths may represent extruded deposits from the renal parenchyma. The radiologic demonstration of both nephrocalcinosis and nephrolithiasis also helps in determining their etiology and thus significantly contributes to the management of the disease. Planar conventional tomography provides a cheaper alternative to CT scanning, and it may be a useful adjunct to conventional radiography.
Degree of Confidence
Plain radiography is a noninvasive and fairly sensitive technique for the detection of nephrocalcinosis. The pattern and distribution of the nephrocalcinosis may suggest the underlying cause. Radiographs appear to show more details than CT scans. Radiographs also seem to be more suitable for follow-up of the course of the disease, and they have a lower radiation burden.
False Positives/Negatives
Plain radiographic detection is not possible until an attenuation of 100 HU. Plain radiography cannot be used to differentiate between the various causes of nephrocalcinosis.3
Computed Tomography
Findings
Axial computed tomography scans obtained from a patient with a long history of renal tubular acidosis (same patient as in Image 11 in Multimedia). These images show bilateral medullary nephrocalcinosis (early arterial phase).
Nonenhanced coronal computed tomography scans through the kidneys. These images show both cortical and medullary nephrocalcinosis (left kidney). Both kidneys appear scarred. Note the thinning of the renal cortex at the upper pole of the left kidney. This patient gave a long history of chronic pyelonephritis, which is an unusual cause of nephrocalcinosis.
CT scanning is said to be the most sensitive imaging modality in the diagnosis of nephrocalcinosis. CT scans depict nephrocalcinosis at an early stage of the disease, provide a better picture of the density and extent of the nephrocalcinosis, and may depict other changes such as renal cysts. In a small series of 13 patients, intravenous urograms showed medullary sponge kidneys (24 kidneys), whereas nonenhanced CT scans showed papillary calcifications in 11 kidneys, 5 of which were not detectable on plain radiographs.19 Hyperattenuating papillae (55-70 HU) without calcification were found in 4 other kidneys.
Hyperoxaluria is characterized by nephrocalcinosis on radiologic examination, and this condition is associated with nephrolithiasis and calcium oxalate crystal deposition in multiple extrarenal organs. CT scanning is a sensitive modality for the detection of systemic oxalosis (eg, in the liver and heart), in addition to nephrocalcinosis. Bilateral attenuating rings in the renal medulla were depicted on nonenhanced CT scans in a patient with marked hypercalcemia and suspected hyperparathyroidism.20
Degree of Confidence
Nonenhanced CT scans can depict nephrocalcinosis, and because CT scanning appears to be the most sensitive and accurate technique, it is the modality of choice. CT scanning is more sensitive than plain radiography in the detection of papillary calcifications, the most frequent complication of medullary sponge kidney.
False Positives/Negatives
The sensitivity of contrast-enhanced CT scanning in the detection of medullary sponge kidneys is markedly lower than that of excretory urography.19 CT images only suggest the possibility of medullary sponge kidneys. This will change with multidetector-row CT (MDCT) scanners and dedicated reformatting protocols.
Magnetic Resonance Imaging
Findings
Magnetic resonance imaging (MRI) is rarely required to diagnose nephrocalcinosis because it does not depict calcium as such.
Ultrasonography
Findings
Sonogram of the right kidney in a woman with nephrocalcinosis. This image shows hyperechoic foci in the pyramids.
Top: Plain radiograph of the kidneys in a patient with a long history of renal tubular acidosis (same patient as in bottom image and Image 12 in Multimedia). This image shows bilateral pyramidal calcification that is consistent with nephrocalcinosis. Bottom: Sonograms of the kidneys in the same patient as above show a hyperechoic medulla associated with echogenic foci, some of which are casting shadows.
Sonogram of a kidney in a patient with medullary sponge kidney. This image shows a hyperechoic medulla associated with echogenic foci, some of which are casting shadows. A hyperechoic medulla can also be seen in conditions that cause hyperuricemia and hypokalemia.
In medullary calcinosis, the margins of the pyramids are echogenic, whereas the center of pyramids remains echolucent. The pyramids are well visualized as rounded or echogenic structures. The pyramids may be densely echogenic, and shadowing may be shown. These findings may be evident on sonograms before they are seen on plain radiographs.
Renal cortical calcification causes increased cortical echogenicity with complete shadowing in severe cases. Secondary pyramidal fibrosis may occur; these may cause echogenic pyramids.
Degree of Confidence
Early medullary nephrocalcinosis can be seen as echogenic pyramids before nephrocalcinosis can be identified on plain abdominal radiographs.
False Positives/Negatives
Causes of focal increases in renal echogenicity (usually nonshadowing) include the following: chronic infarction (eg, Hgb S), acute bacterial focal nephritis, angiomyolipoma, hemangioma, oncocytoma, and malignancy (eg, renal cell carcinoma, sarcoma, metastases).
The differential diagnosis of echogenic renal pyramids in children includes nephrocalcinosis as the single most frequent cause. However, a multitude of other causes involve echogenic pyramids in the absence of nephrocalcinosis. These include the following:
- Protein deposits – Proteinuria (dehydration), toxic shock syndromes, sepsis, degenerative leukoencephalopathy, and hypotensive and/or hypovolemic shock
- Vascular congestion and/or occlusion – Sickle cell disease
- Systemic infection – Bacterial septicemia, candidal infection, cytomegaloviral infection, acquired immunodeficiency syndrome (AIDS)21 (eg, Mycobacterium avium-intracellulare, Pneumocystis carinii)
- Metabolic – Gout, Lesch-Nyhan syndrome, glycogen storage disease, hypokalemia, primary aldosteronism, pseudo-Bartter syndrome, Wilson syndrome, Fanconi syndrome, tyrosinosis, cholestatic jaundice, oxalosis, alpha-antitrypsin deficiency
- Fibrosis – Renal pyramidal fibrosis, congenital hepatic fibrosis
- Unknown causes – Pyloric stenosis, metabolic alkalosis, tubular ectasia, intrarenal reflux, Crohn disease
- Cystic medullary disease – Medullary sponge kidney
Echogenic pyramids and hyperechoic rings may be present in the periphery of the renal pyramids in adults. These can be divided into 2 groups: normal variants and nephrocalcinosis. Nephrocalcinosis can be subdivided as follows:
- Hypercalcemia
- Hypercalciuria
- Medullary sponge kidney
- Oxalosis
- No nephrocalcinosis
- Renal tubular ectasia
- Medullary sponge kidney
- Congenital hepatic fibrosis
- Sarcoidosis
- Hyperuricemia
- Glomerulonephritis
- Rheumatoid arthritis with amyloid
- Analgesic nephropathy
- Hypocalcemia
- Hypokalemia
- Addison disease (normal calcium, potassium, and uric acid levels)
- AIDS-related M avium-intracellulare infection, in which the increased attenuation is secondary to protein contents
Nuclear Imaging
Findings
The role of nuclear medicine is confined to assessing renal function by means of isotope renography, particularly when renal surgery is being considered.
More on Nephrocalcinosis |
| Overview: Nephrocalcinosis |
 Imaging: Nephrocalcinosis |
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References
Albright F, Baird PC, Cope O, Bloomberg E. Studies on the physiology of the parathyroid glands. IV. Renal complications of hyperparathyroidism. Am J Med Sci. 1934;187(1):49-65.
Balogun RA, Adams ND, Palmisano J, et al. Focal segmental glomerulosclerosis, proteinuria and nephrocalcinosis associated with renal tubular acidosis. Nephrol Dial Transplant. Feb 2002;17(2):308-10. [Medline]. [Full Text].
Cheidde L, Ajzen SA, Tamer Langen CH, Christophalo D, Heilberg IP. A critical appraisal of the radiological evaluation of nephrocalcinosis. Nephron Clin Pract. 2007;106(3):c119-24. [Medline].
Akhan O, Ozmen MN, Coskun M, et al. Systemic oxalosis: pathognomonic renal and specific extrarenal findings on US and CT. Pediatr Radiol. 1995;25(1):15-6. [Medline].
Hill SC, Hoeg JM, Avila NA. Nephrocalcinosis in homozygous familial hypercholesterolemia: ultrasound and CT findings. J Comput Assist Tomogr. Jan-Feb 1991;15(1):101-3. [Medline].
Falkoff GE, Rigsby CM, Rosenfield AT. Partial, combined cortical and medullary nephrocalcinosis: US and CT patterns in AIDS-associated MAI infection. Radiology. Feb 1987;162(2):343-4. [Medline]. [Full Text].
Afschrift M, Nachtegaele P, Van Rattinghe R, et al. Nephrocalcinosis demonstrated by ultrasound and CT. Pediatr Radiol. 1983;13(1):42-3. [Medline].
Sumner TE, Volberg FM, Karstaedt N, Ward CF, Lorentz WB. Hypophosphatasia and nephrocalcinosis demonstrated by ultrasound and CT. Clin Nephrol. Dec 1984;22(6):317-9. [Medline].
Manz F, Jaschke W, van Kaick G, Waldherr R, Willich E. Nephrocalcinosis in radiographs, computed tomography, sonography and histology. Pediatr Radiol. 1980;9(1):19-26. [Medline].
Fuster D. [Pathophysiology and diagnosis of nephrocalcinosis] [German]. Ther Umsch. May 2007;64(5):287-90. [Medline].
Igarashi T, Hayakawa H, Shiraga H, et al. Hypercalciuria and nephrocalcinosis in patients with idiopathic low-molecular-weight proteinuria in Japan: is the disease identical to Dent's disease in United Kingdom?. Nephron. 1995;69(3):242-7. [Medline].
Narendra A, White MP, Rolton HA, et al. Nephrocalcinosis in preterm babies. Arch Dis Child Fetal Neonatal Ed. Nov 2001;85(3):F207-13. [Medline]. [Full Text].
[Best Evidence] Porter E, McKie A, Beattie TJ, et al. Neonatal nephrocalcinosis: long term follow up. Arch Dis Child Fetal Neonatal Ed. Sep 2006;91(5):F333-6. [Medline].
Saarela T, Lanning P, Koivisto M, Paavilainen T. Nephrocalcinosis in full-term infants receiving furosemide treatment for congestive heart failure: a study of the incidence and 2-year follow up. Eur J Pediatr. Aug 1999;158(8):668-72. [Medline].
Solivetti FM, Paganelli C, Zoffoli M, et al. Nephrocalcinosis induced by long-term therapy with furosemide. J Clin Ultrasound. Nov-Dec 1997;25(9):519-20. [Medline].
Kim YG, Kim B, Kim MK, et al. Medullary nephrocalcinosis associated with long-term furosemide abuse in adults. Nephrol Dial Transplant. Dec 2001;16(12):2303-9. [Medline]. [Full Text].
Simões A, Domingos F, Prata MM. Nephrocalcinosis induced by furosemide in an adult patient with incomplete renal tubular acidosis. Nephrol Dial Transplant. May 2001;16(5):1073-4. [Medline]. [Full Text].
Soylu OB, Ecevit C, Altinöz S, et al. Nephrocalcinosis in glucose-galactose malabsorption: nephrocalcinosis and proximal tubular dysfunction in a young infant with a novel mutation of SGLT1. Eur J Pediatr. Feb 21 2008;epub ahead of print. [Medline].
Ginalski JM, Schnyder P, Portmann L, Jaeger P. Medullary sponge kidney on axial computed tomography: comparison with excretory urography. Eur J Radiol. Mar-Apr 1991;12(2):104-7. [Medline].
Curry NS, Gordon L, Gobien RP, Lott M. Renal medullary "rings": possible CT manifestation of hypercalcemia. Urol Radiol. 1984;6(1):48-50. [Medline].
Bargman JM, Wagner C, Cameron R. Renal cortical nephrocalcinosis: a manifestation of extrapulmonary Pneumocystis carinii infection in the acquired immunodeficiency syndrome. Am J Kidney Dis. Jun 1991;17(6):712-5. [Medline].
Marengo SR, Romani AM. Oxalate in renal stone disease: the terminal metabolite that just won't go away. Nat Clin Pract Nephrol. Jul 2008;4(7):368-77. [Medline]. [Full Text].
Moudgil A, Rodich G, Jordan SC, Kamil ES. Nephrocalcinosis and renal cysts associated with apparent mineralocorticoid excess syndrome. Pediatr Nephrol. Nov 2000;15(1-2):60-2. [Medline].
Schell-Feith EA, Kist-van Holthe JE, Conneman N, et al. Etiology of nephrocalcinosis in preterm neonates: association of nutritional intake and urinary parameters. Kidney Int. Nov 2000;58(5):2102-10. [Medline]. [Full Text].
Rönnefarth G, Misselwitz J. Nephrocalcinosis in children: a retrospective survey. Members of the Arbeitsgemeinschaft für pädiatrische Nephrologie. Pediatr Nephrol. Sep 2000;14(10-11):1016-21. [Medline].
Garel L, Filiatrault D, Robitaille P. Nephrocalcinosis in Bartter's syndrome. Pediatr Nephrol. Jul 1988;2(3):315-7. [Medline].
Rausch HP, Hanefeld F, Kaufmann HJ. Medullary nephrocalcinosis and pancreatic calcifications demonstrated by ultrasound and CT in infants after treatment with ACTH. Radiology. Oct 1984;153(1):105-7. [Medline]. [Full Text].
Cumming WA, Ohlsson A. Nephrocalcinosis in Bartter's syndrome. Demonstration by ultrasonography. Pediatr Radiol. 1984;14(2):125-6. [Medline].
al-Murrani B, Cosgrove DO, Svensson WE, Blaszczyk M. Echogenic rings--an ultrasound sign of early nephrocalcinosis. Clin Radiol. Jul 1991;44(1):49-51. [Medline].
Brennan RP, Pearlstein AE, Miller SA. Computed tomography of the kidneys in a patient with methoxyflurane abuse. J Comput Assist Tomogr. Jan-Feb 1988;12(1):155-6. [Medline].
Campfield T, Bednarek FJ, Pappagallo M, et al. Nephrocalcinosis in premature infants: variability in ultrasound detection. J Perinatol. Oct-Nov 1999;19(7):498-500. [Medline].
Cockell KA, L'Abbé MR, Belonje B. The concentrations and ratio of dietary calcium and phosphorus influence development of nephrocalcinosis in female rats. J Nutr. Feb 2002;132(2):252-6. [Medline]. [Full Text].
Faqeih E, Al-Akash SI, Sakati N, Teebi PA. Four siblings with distal renal tubular acidosis and nephrocalcinosis, neurobehavioral impairment, short stature, and distinctive facial appearance: a possible new autosomal recessive syndrome. Am J Med Genet A. Sep 1 2007;143A(17):1951-7. [Medline].
Forget S, Patriquin HB, Dubois J, et al. The kidney in children with tyrosinemia: sonographic, CT and biochemical findings. Pediatr Radiol. Feb 1999;29(2):104-8. [Medline].
Hoffbrand BI, Oppenheimer SM, Sachs ML, Wrong OM. Nodular cortical nephrocalcinosis: a benign and hitherto undescribed form of renal calcification. Nephron. 1987;46(4):370-2. [Medline].
Hughes JJ, Wilder WM. Computed tomography of renal sarcoidosis. J Comput Assist Tomogr. Nov-Dec 1988;12(6):1057-8. [Medline].
Karstrup S, Hegedüs L, Holm HH. Ultrasonically guided chemical parathyroidectomy in patients with primary hyperparathyroidism: a follow-up study. Clin Endocrinol (Oxf). May 1993;38(5):523-30. [Medline].
Lucaya J, Enriquez G, Nieto J, et al. Renal calcifications in patients with autosomal recessive polycystic kidney disease: prevalence and cause. AJR Am J Roentgenol. Feb 1993;160(2):359-62. [Medline]. [Full Text].
Miller DL, Doppman JL, Chang R, et al. Angiographic ablation of parathyroid adenomas: lessons from a 10-year experience. Radiology. Dec 1987;165(3):601-7. [Medline]. [Full Text].
Mrowka C, Adam G, Sieberth HG, Matern S. Caroli's syndrome associated with medullary sponge kidney and nephrocalcinosis. Nephrol Dial Transplant. Jun 1996;11(6):1142-5. [Medline]. [Full Text].
Schell-Feith EA, Holscher HC, Zonderland HM, et al. Ultrasonographic features of nephrocalcinosis in preterm neonates. Br J Radiol. Nov 2000;73(875):1185-91. [Medline]. [Full Text].
Schepens D, Verswijvel G, Kuypers D, Vanrenterghem Y. Images in nephrology. Renal cortical nephrocalcinosis. Nephrol Dial Transplant. Jul 2000;15(7):1080-2. [Medline]. [Full Text].
Shaer AJ. Inherited primary renal tubular hypokalemic alkalosis: a review of Gitelman and Bartter syndromes. Am J Med Sci. Dec 2001;322(6):316-32. [Medline].
Shuman WP, Mack LA, Rogers JV. Diffuse nephrocalcinosis: hyperechoic sonographic appearance. AJR Am J Roentgenol. Apr 1981;136(4):830-2. [Medline]. [Full Text].
Solbiati L, Giangrande A, De Pra L, et al. Percutaneous ethanol injection of parathyroid tumors under US guidance: treatment for secondary hyperparathyroidism. Radiology. Jun 1985;155(3):607-10. [Medline]. [Full Text].
Ter Meulen CG, Pieters GF, Huysmans FT. Flaccid paresis due to distal renal tubular acidosis preceding systemic lupus erythematosus. Neth J Med. Mar 2002;60(1):29-32. [Medline]. [Full Text].
Toyoda K, Miyamoto Y, Ida M, Tada S, Utsunomiya M. Hyperechoic medulla of the kidneys. Radiology. Nov 1989;173(2):431-4. [Medline]. [Full Text].
Verge CF, Lam A, Simpson JM, et al. Effects of therapy in X-linked hypophosphatemic rickets. N Engl J Med. Dec 26 1991;325(26):1843-8. [Medline].
Yeung SJ, McCutcheon IE, Schultz P, Gagel RF. Use of long-term intravenous phosphate infusion in the palliative treatment of tumor-induced osteomalacia. J Clin Endocrinol Metab. Feb 2000;85(2):549-55. [Medline]. [Full Text].
Further Reading
Keywords
nephrocalcinosis, male urogenital disease, urologic diseases, kidney disease, medullary sponge kidney, renal lithiasis, urolithiasis, medullary calcification, diffuse renal calcification, nephrolithiasis, medullary nephrocalcinosis, cortical nephrocalcinosis, hypercalcemia, hypercalciuria, hyperoxaluria, Bartter syndrome, hyperparathyroidism, primary, hyperparathyroidism,secondary, Butler-Albright disease
