Kidney Infarction - Causes, Clinical Features, Diagnosis, and Treatment

Introduction

Infarction is the death of the cells or tissues (necrosis) because of insufficient blood supply to a particular region. It could be due to blockage, rupture, or constriction of the blood vessels. When cell death occurs in the kidneys, it is called kidney infarction. Kidney infarction is a rare condition. It can progress to different kidney ailments depending upon the severity. It is mainly missed as the patients complain of abdominal or flank pain resembling other common conditions such as kidney stones and kidney infections, suggesting that the frequency is higher than reported.

What Causes Kidney Infarction?

Causes of kidney infarction include:

• Thromboembolism- Thromboembolism is the blockage of a blood vessel by a blood clot (emboli) dislodging from another part of the circulation. This is one of the common causes of renal infarction. Emboli are mostly dislodged during a heart attack, heart diseases related to the valves, or irregular heartbeats.

• Aortic Dissection- Aorta is the main blood vessel of the body. Aortic dissection is a severe condition caused due to a rupture in the aorta. Blood leaks through the rupture, causing the aorta to split into two.

• Renal artery Dissection- This condition is the dissection of the kidney blood vessel due to any kind of injury, injury to the abdomen, aortic dissection, accumulation of cholesterol in the blood vessels (atherosclerosis), connective tissue disorder, or the narrowing of the medium-sized blood vessels of the body (fibromuscular dysplasia).

• Iatrogenic- Iatrogenic disorders are diseases that occur in the process of medical treatment, such as angiography.

• Vasculitis- This condition arises due to inflammation of the blood vessels.

• Malignant Hypertension- This is an abrupt increase in high blood pressure.

• Renal Vein Occlusion- The blockage of one or both kidney blood vessels leads to chronic kidney disease. It is a rare condition occurring in infants due to dehydration.

• Kidney Transplant Torsion- This is a complication of a kidney transplant where the transplanted kidney rotates, leading to the constriction of the blood vessels and causing kidney infarction.

• Sickle Cell Disease- This group of inherited blood disorders leads to misshapen red blood cells.

• Cocaine- The misuse of cocaine or a stimulant can cause kidney infarction.

• Kidney trauma.

• Kidney cancer.

• Kidney Vascular Disease- This disease affects the blood flow in and out of the kidneys.

• Systemic Candidiasis is a group of fungal infections affecting the body's blood, heart, brain, eyes, and other organs.

• Takotsubo Syndrome- This is a heart disease characterized by momentary loss of function in the heart's left chamber.

What Are the Clinical Features of Kidney Infarction?

Kidney infarction is usually asymptomatic and detected late. The sign and symptoms include:

Pain in the abdomen or the flank.

• Hematuria- The presence of blood in the urine.

• Proteinuria- This is a condition where there is a presence of protein in the urine.

• Nausea and vomiting.

• Fever.

• Hypertension- A high blood pressure.

How Is Kidney Infarction Diagnosed?

Various tests are carried out to diagnose the condition. They are:

• Complete Blood Count- To find any possible abnormality in the blood test.

• Renal Function Panel- This group of tests gives information about the health of the kidneys.

• Urinalysis- A urine test is carried out to detect the presence of protein or blood in the urine.

• LDH (Lactate Dehydrogenase) Test- The lactate dehydrogenase test is the test to detect the presence of any damage to the tissues.

• CT (Computed Tomography) Scan- Computed tomography is a procedure that combines X-rays and computer technology to make images of internal organs. A CT scan is the first test carried out on individuals with flank pain with or without hematuria. CT angiograms can detect blocked blood vessels. In case of injury, detection of hematoma (blood clot outside the blood vessels) is necessary. In sporadic cases, the kidney vein may also be occluded. Renal infarctions are mainly detected on contrast images of the kidneys carried out with the help of contrast media or dyes. A wedge-shaped defect of the kidneys is demonstrated. In around fifty percent of the cases, a thin line of blood (cortical rim sign) is seen in the cortex or outer layer of the kidneys. This sign is not usually present immediately after infarction but can be detected after eight hours of infarction.

• Ultrasound- Ultrasound is the imaging procedure that uses sound waves to form images of the organs. Although a CT scan is the first diagnosis choice, an ultrasound might be performed if the condition's clinical presentation is indistinct. Acute infarction appears as an absence of blood supply on color doppler examination. If the whole kidney is involved, there will be a complete absence of blood supply, or it can vary if a few blood vessels are involved. The lack of blood flow can also be detected in renal blood vessels. Contrast-enhanced ultrasound is an ultrasound that uses dyes or contrast media to detect the anomaly and can confirm the diagnosis. The infarcts or blockages appear as wedge-shaped areas of no blood supply.

How Is Kidney Infarction Treated?

The treatment of kidney infarction depends upon the cause. Restoring the blood flow can be difficult if the renal blood vessel is completely blocked. Endovascular treatment can save the kidneys if the patient is on the edge of kidney failure. The treatment plans include the following:

• Anticoagulation- This treatment inhibits blood clot formation within the blood vessels. This is a treatment choice if the infarction is due to a displaced blood clot. The therapy begins with the drug heparin, followed by warfarin.

• Endovascular Treatment- This is the most effective treatment modality. This treatment involves the use of a catheter to remove the cause of blockage within the blood vessels. If the main artery of the kidney is infarcted for not more than two days, then endovascular therapy is carried out to remove the blockage. If the individual has high blood pressure, then the blood pressure should be normalized with drugs such as ACE (angiotensin-converting enzyme) inhibitors or angiotensin receptor blockers.

• Open Surgery- Surgery is generally performed in individuals who develop infarction due to significant kidney injury.

Conclusion

Kidney infarction is a rare condition where the kidney blood vessels get blocked, causing less or no blood flow to the kidney tissues, leading to death. The symptoms are often similar to kidney stones and other kidney diseases. Early diagnosis and treatment are important in preventing further kidney damage. The prognosis of the treatment is suitable if diagnosed early.