Introduction:
Fraley syndrome is a rare condition in which distention and dilation of the calyx occur due to the obstruction of the collecting system of the kidneys. This syndrome is characterized by nephralgia and calyectasis. It is also referred to as hydrocalyx. Hydrocalyx can be congenital or acquired. Fraley syndrome usually remains asymptomatic. This condition is common in young women, and the upper calyx of the kidneys is commonly affected.
What Is Fraley Syndrome?
Fraley syndrome is named after a urologist Elwin E. Fraley. Fraley first described this condition in December 1996 in the New England Journal of Medicine. Fraley syndrome is a rare disease in which obstruction of the superior infundibulum of the upper calyx of the kidney causes dilation and distention of the calyx. The obstruction in the collecting system of the kidney is caused by the compression of the calyceal infundibulum by a branch of the renal artery. The obstruction of the proximal collecting system by the renal artery can cause filling defects in the calyx, pelvis, or ureter.
What Is Calyx and Infundibulum of the Kidney?
The renal pelvis, or the renal infundibulum, is a large chamber in the kidney that collects urine when it is produced. It is a part of the pelvicalyceal system of the kidney. It forms the connection between the calyces and the ureter of the kidneys. Calyces are cuplike projections that interrupt the periphery of the renal pelvis. The minor calyx surrounds the renal papillae of the pyramid and collects urine present in the pyramid. The union of several minor calyces forms a major calyx.
What Are the Causes of Fraley Syndrome?
Fraley syndrome usually occurs in individuals with anatomically low-lying kidneys, which is called ptosis of the kidney. It usually occurs on the right side, but both kidneys can be affected in some cases. Fraley syndrome is commonly seen on the right kidneys because the blood vessels on the right side are longer due to the position of the aorta, which is present slightly on the left from the midline. The crossing renal vessels may cover a portion of the superior infundibulum and cause compression. This obstructs the upper calyx of the kidneys and causes distention of the calyx.
How Does Fraley Syndrome Occur?
If the renal artery crosses over the superior infundibulum of the kidneys, fluid accumulation occurs in the calyx due to the compression of the infundibulum by the renal artery. This leads to distension of the calyx. The distension of the calyx allows even distribution of the backed-up fluid and slows down the amount of damage to the kidneys. This impairs the ability of the kidney to remove waste and disrupts the mineral and fluid balance. This impairment increases the risk of infection and stone formation. The infections can lead to inflammation of the lining of the urinary tract. The walls of the calyces are thickened, and the blood flow is interrupted. This may result in tissue damage if left untreated. Further, the damaged tissue is replaced by fibrous scar tissue. Renal scarring may result in high blood pressure.
What Are the Signs and Symptoms Associated With Fraley Syndrome?
Fraley syndrome usually does not present any symptoms. If present, the symptoms can be asymptomatic microhematuria, severe and recurrent flank pain, kidney stone formation, and infections. The classic symptoms of Fraley syndrome are ipsilateral flank pain and hematuria. It can also cause fever, dysuria, polyuria, nausea, and vomiting. Chronic infections may progress to cause renal damage if left untreated. In rare cases, it can also result in sepsis and kidney failure.
How Is Fraley Syndrome Diagnosed?
The clinical presentation of Fraley syndrome is uncharacteristic and variable. Hence, this condition is diagnosed bearing in mind other conditions such as calyceal diverticulum, renal cyst, and Fraley syndrome. The diagnostic tests are performed based on the symptoms of the patient.
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Urinalysis and Complete Blood Count - These tests are performed if the patient presents with flank pain and hematuria.
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Ultrasound or CT scan (Computed Tomography) - It is performed to visualize the affected side. It shows the presence of distension on the affected side.
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CT Angiogram - It is performed to confirm the diagnosis. It tracks the vascular path of the vessels over the kidney and shows the presence of obstruction of the superior calyx by the renal artery.
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A Cystoscopy With a Retrograde Pyelogram - It is performed to determine the level of obstruction and to rule out the presence of nephrolithiasis.
For asymptomatic individuals, hematuria may be detected during routine urinalysis. Further, imaging tests are performed to determine the cause.
How Is Fraley Syndrome Treated?
The treatment for Fraley syndrome is based on the severity of the symptoms and the presence of renal damage. Conservative management is preferred if the kidneys are normal and the symptoms are minimal. Surgical intervention is required if severe symptoms are present.
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A Partial Nephrectomy - It is performed to remove the affected calyces to relieve the obstruction. But, this procedure causes loss of nephrons and reduces renal function. A simple nephrectomy is performed if multiple and mega-calycosis are present with renal damage.
Recent advancements in microscopic surgical techniques help the surgeon re-route the renal artery and relieve the compression on the calyces. This also preserves the nephrons and renal function.
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Laparoscopic Nephron-Sparing Calycectomy - It is performed if laparoscopic ablation is required to ablate the renal parenchyma that drains into the affected calyx. For treating infundibular stenosis, intrarenal surgery may be performed with ureteroscopy using holmium: yttrium-aluminum-garnet (YAG) laser incision.
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Other Procedures - Procedures like infundibulo-infundibulostomy, Fraley’s infundibulopyelostomy, a Heineke-Mikulicz-type infundibulorrhaphy with vasopexy, simple vasopexy are performed in Fraley syndrome.
What to Expect With Fraley Syndrome?
The patients with Fraley syndrome perform well. Advancements in surgical techniques are effective in relieving obstruction and treating Fraley syndrome. The treatment outcomes are good, and the patients do not experience any long-term problems after the treatment.
Conclusion:
Fraley syndrome is a rare syndrome that can become a life-threatening condition. If left untreated, it can cause chronic infections and may progress to kidney failure and sepsis. Early diagnosis is essential to prevent the progression of this disease. Advanced surgical techniques are helpful in managing individuals with Fraley syndrome.
