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Pediatrics: General Medicine > Nephrology
Renal Cortical Necrosis
Article Last Updated: Dec 13, 2007
AUTHOR AND EDITOR INFORMATION
Section 1 of 9  
Author: Elif Erkan, MD, Assistant Professor, Department of Pediatrics, Division of Pediatric Nephrology, University of Rochester School of Medicine
Coauthor(s):
Prasad Devarajan, MD, Louise M Williams Endowed Chair in Pediatrics, Professor of Pediatrics and Developmental Biology, Director of Nephrology and Hypertension, Director of Clinical Nephrology Laboratories, Chief Executive Officer of Dialysis Unit, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine
Editors: Laurence Finberg, MD, Clinical Professor, Department of Pediatrics, University of California at San Francisco and Stanford University; Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine.com, Inc; Luther Travis, MD, William W Glauser Professor of Pediatrics and Pediatric Nephrology, Department of Pediatrics, Divisions of Nephrology and Diabetes, University of Texas Medical Branch and Children's Hospital; Howard Trachtman, MD, Program Director, Pediatrics Research, Schneider Children's Hospital, Department of Pediatrics, Division of Nephrology, Professor, Albert Einstein College of Medicine; Craig B Langman, MD, The Isaac A Abt, MD, Professor of Kidney Diseases, Feinberg School of Medicine, Northwestern University; Division Head of Kidney Diseases, Children's Memorial Hospital, Chicago
Author and Editor Disclosure
Synonyms and related keywords:
renal cortical necrosis, RCN, acute renal failure, acute renal failure in pregnancy, kidney failure, dehydration, placental abruption, ischemic necrosis of the renal cortex, renal arterial perfusion, acute tubular necrosis, hemolytic uremic syndrome, HUS, septic abortion, acute renal failure, oliguria, hematuria, perinatal asphyxia, cyanotic heart disease, eclampsia, hypotension, congenital heart disease, anemia, hemolytic disease, gastroenteritis
Background
Renal cortical necrosis (RCN) is a rare cause of acute renal failure secondary to ischemic necrosis of the renal cortex. The lesions are usually caused by significantly diminished renal arterial perfusion secondary to vascular spasm, microvascular injury, or intravascular coagulation. RCN is usually extensive, although focal and localized forms occur. In most cases, the medulla, juxtamedullary cortex, and a thin rim of subcapsular cortex are spared.
Pathophysiology
Cases are usually bilateral. Although the pathogenesis remains unclear, the presumed initiating factor is intense vasospasm of the small vessels. If this vasospasm is brief and vascular flow is reestablished, acute tubular necrosis results. More prolonged vasospasm can cause necrosis and thrombosis of the distal arterioles and glomeruli, and RCN ensues. In hemolytic-uremic syndrome (HUS) and septic abortion, an additional mechanism involves endotoxin-mediated endothelial damage that leads to vascular thrombosis. RCN in placental abruption may be due to a combination of a hypercoagulable state, endothelial injury, and intravascular thrombosis.
Frequency
United States
RCN accounts for 2% of all cases of acute renal failure in adults and more than 20% of acute renal failure during the third trimester of pregnancy. RCN was detected by postmortem examination in 5% of infants aged 3 months or younger at death.
International
RCN incidence is higher in developing countries, ranging from 6-7% of all cases of acute renal failure. The incidence of acute cortical necrosis has been decreasing in the developing countries over the past years. The incidence of RCN was reported to be 3.12% of all cases of acute renal failure based on a study from India.1 Acute cortical necrosis due to obstetric causes was observed in 56.2% of patients whereas nonobstetric causes accounted for acute renal failure in 43.8% of the patients.
Mortality/Morbidity
- In untreated patients, the mortality rate exceeds 50%. Early initiation of dialysis significantly diminishes this rate.
Race
- RCN has no racial predilection.
Sex
- In childhood, RCN equally affects both sexes.
- In adults, RCN occurs more frequently in women because the most common cause is placental abruption (50% of all cases).
Age
- The first peak of RCN occurrence is in early infancy and is associated with severe perinatal events or conditions.
- RCN in childhood is usually secondary to HUS or severe volume depletion.
- Occurrence also peaks in women of childbearing age because of obstetric causes.
History
- Renal failure
- Neonatal conditions
- Perinatal asphyxia
- Bleeding
- Cyanotic heart disease
- Childhood conditions
- Diarrhea
- Vomiting
- Blood in stools
- HUS
- Pregnancy
- Bleeding
- Abortion
- Symptoms of eclampsia
- Other
- Severe trauma
- Snakebite (eg, sea snake, cobra, green pit viper, Russell viper)
Physical
- Kidney
- Abdominal or bilateral costovertebral tenderness
- Palpable, tender kidneys
- Shock
- Hypotension
- Tachycardia
- Delayed capillary refill
- Pregnancy
- Lower abdominal tenderness
- Contracted uterus
- Vaginal bleeding
Causes
- Neonatal conditions
- Congenital heart disease
- Fetal-maternal transfusion
- Dehydration
- Perinatal asphyxia
- Anemia
- Placental hemorrhage
- Severe hemolytic disease
- Sepsis
- Childhood conditions
- HUS
- Acute gastroenteritis with dehydration
- Pregnancy-related conditions (more than 50% of cases)
- Placental abruption
- Infected abortion
- Prolonged intrauterine fetal death
- Severe eclampsia
- Miscellaneous
- Sepsis
- Shock
- Trauma
- Snakebite
- Hyperacute kidney transplant rejection
- Poisons
- Drugs (eg, nonsteroidal anti-inflammatory drugs)
- Contrast media
Acute Tubular Necrosis
Other Problems to be Considered
Renal artery thromboembolism
Renal infarction
Renal vein thrombosis
Lab Studies
- Serum electrolyte measurements and renal function tests are used to check for hyperkalemia, hypocalcemia, metabolic acidosis, and elevated creatinine.
- A CBC count may reveal hemolytic anemia and thrombocytopenia.
- Coagulation studies detect low fibrinogen levels and increased fibrin-degradation products.
- Urinalysis detects hematuria, proteinuria, RBC casts, and granular casts.
Imaging Studies
- Radiography: Thin cortical shells or tram lines caused by calcification are a radiologic hallmark, but they develop only 4-5 weeks after the initial insult.
- Ultrasonography
- The sonogram initially shows enlarged kidneys with reduced blood flow.
- Cortical tissue becomes shrunken later in disease progression.
- Contrast-enhanced CT scanning
- CT scanning with contrast are the most sensitive imaging modality.
- Diagnostic features include absent opacification of the renal cortex and enhancement of subcapsular and juxtamedullary areas and of the medulla without excretion of contrast medium.
- Initiating hemodialysis immediately after the procedure may be necessary to minimize further contrast-mediated renal damage.
- Renal scanning
- Diethylenetriamine pentaacetic acid (DTPA) scan reveals markedly diminished perfusion with delayed or no function.
- Renal scan is the imaging technique of choice to diagnose renal cortical necrosis (RCN) in transplant kidneys or if contrast-enhanced CT scanning are unavailable.
Procedures
- Kidney biopsy findings provide the definitive diagnosis and prognostic information; biopsy is indicated if the diagnosis is unclear and when no contraindications are present.
Histologic Findings
- RCN is classified into 5 pathologic forms, depending on severity, as shown below. RCN classifications are as follows:
- Focal pathologic form: Kidneys show focally necrotic glomeruli without thrombosis and patchy necrosis of tubules.
- Minor pathologic form: Larger foci of necrosis are evident with vascular and glomerular thrombi.
- Patchy pathologic form: Patches of necrosis may occupy two thirds of the cortex.
- Gross pathologic form: Almost the entire cortex is involved. Thrombosis of the arteries is more widespread.
- Confluent pathologic form: Kidneys show widespread glomerular and tubular necrosis with no arterial involvement.
- Studies have shown that patients with HUS with thrombotic microangiopathy (TMA) involving arteries have a higher likelihood of progressing into acute cortical necrosis compared with patients with predominant glomerular TMA.2
Medical Care
- The cornerstones of therapy are to restore hemodynamic stability, institute early dialytic therapy, and treat the underlying cause.
- Most cases initially require intensive care.
- Restoration of hemodynamic stability may require use of IV crystalloids, colloids, blood products, and/or pressors to maintain blood pressure and cardiac output.
- Early institution of dialysis treatment for renal failure is crucial for patients who are oliguric. Refer to relevant chapters for medical management of acute renal failure, including Hyperkalemia, fluid overload, and Acidosis, Metabolic.
Surgical Care
- Most patients require an access (eg, hemocatheter, peritoneal dialysis catheter) to institute dialysis.
Consultations
- Consult a pediatric nephrologist to manage acute renal failure and for ongoing chronic renal replacement therapy.
- Consultation with other specialties may be needed, depending on the etiology of the renal cortical necrosis (RCN).
Diet
- Ensure adequate energy intake.
- Patients with compromised kidney function require a low-potassium, low-phosphorus diet.
Activity
Activity should continue as tolerated.
Complications
- Acute renal failure is typical, with associated complications (eg, hyperkalemia, fluid overload).
- Chronic renal failure, occurring in 30-50% of patients, requires dialysis and transplantation.
Prognosis
- The most important prognostic factors are the extent of necrosis, duration of oliguria, and severity of associated conditions.
- Infant survival rates are low because of associated conditions.
- Severe congenital heart disease is a major risk factor for death.
- Of those patients who survive, most require dialysis for variable periods of time, depending on the extent of necrosis.
- Some patients have recovered renal function even after several months of oliguria.
Patient Education
Medical/Legal Pitfalls
- Failure to consider the diagnosis in a pregnant woman with sudden onset of abdominal pain, a tender uterus, and hematuria, especially during the third trimester
- Failure to consider the diagnosis in a newborn or young child with dehydration, oliguria, and hematuria
- Prakash J, Vohra R, Wani IA, et al. Decreasing incidence of renal cortical necrosis in patients with acute renal failure in developing countries: a single-centre experience of 22 years from Eastern India. Nephrol Dial Transplant. Apr 2007;22(4):1213-7. [Medline].
- Kamioka I, Nozu K, Fujita T, et al. Prognosis and pathological characteristics of five children with non-Shiga toxin-mediated hemolytic uremic syndrome. Pediatr Int. Apr 2007;49(2):196-201. [Medline].
- Ali BH, Al-Qarawi AA, Mahmoud OM, Hashad M. Influence of spironolactone treatment on gentamicin-induced nephrotoxicity in rats. Basic Clin Pharmacol Toxicol. Jul 2004;95(1):20-3. [Medline].
- Ali SS, Rizvi SZ, Muzaffar S, et al. Renal cortical necrosis: a case series of nine patients & review of literature. J Ayub Med Coll Abbottabad. Apr-Jun 2003;15(2):41-4. [Medline].
- Chugh KS, Jha V, Sakhuja V, Joshi K. Acute renal cortical necrosis--a study of 113 patients. Ren Fail. 1994;16(1):37-47. [Medline].
- Hashimoto S, Shiroshita K, Sakurai T, et al. Unilateral renal cortical necrosis with contralateral hydronephrosis after surgery for uterus carcinoma. Clin Exp Nephrol. Mar 2003;7(1):72-6. [Medline].
- Lerner GR, Kurnetz R, Bernstein J, et al. Renal cortical and renal medullary necrosis in the first 3 months of life. Pediatr Nephrol. Nov 1992;6(6):516-8. [Medline].
- Mertens PR, Duque-Reina D, Ittel TH, et al. Contrast-enhanced computed tomography for demonstration of bilateral renal cortical necrosis. Clin Investig. Jul 1994;72(7):499-501. [Medline].
- Racusen LC, Solez K. Renal infarction, cortical necrosis, and atheroembolic disease. In: Tisher CC, Brenner BM, eds. Renal Pathology. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 1994:810-31.
Renal Cortical Necrosis excerpt Article Last Updated: Dec 13, 2007
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