Varicocele and its causes

• The causes of varicocele can be divided into primary and secondary causes.
• It has been found that one of the causes of varicocele is a genetic predisposition to suffer from it, which is one of the primary causes.
• Among the secondary causes of varicocele are diseases or dysfunctions that cause it, such as liver cirrhosis or carcinomas or tumours.

A varicocele is a soft, movable mass of blood of venous origin that forms by venous retention and pooling in a collection of veins around the testicles in a network called the pampiniform plexus.

The accumulation of venous blood that we call varicocele is an entity that occurs in approximately 15% of the male population. 

It usually does not cause symptoms until advanced stages of the disease and is usually discovered in a primary care or urology consultation during a physical examination to look for causes of infertility or non-specific pain in the area.

Sometimes it is necessary to confirm the initial suspicion of varicocele by performing a testicular ultrasound. Colour Doppler ultrasound is usually the most useful tool in these cases as it provides information on blood flow and is more sensitive than the usual testicular ultrasound in detecting this venous accumulation, which we call varicocele.

The main symptom or sign of varicocele is the enlargement of the scrotal sac on one side in relation to the other. It is much more common on the left side than on the right, and in a small percentage of the population it is possible to find it on both sides at the same time.

The growth of the venous accumulation that we call varicocele can degenerate into pain if the size reaches a significant volume. A feeling of heaviness on the side with the varicocele is more common, with the sensation of a weight pushing down on the scrotal sac, especially when the patient is standing upright.

Infertility is possible in males with varicocele. Only 16% of patients with varicocele suffer from infertility due to this cause, although it is the most prevalent cause of male infertility that is amenable to surgical intervention.

The possibility of genetically altering the spermatozoa produced inside the testicle and testicular atrophy may be related to the presence of a varicocele. 

It seems correct to think, at least this is the direction taken by the latest scientific studies on the subject, that the difficulty in the vascularisation of the testicle and the increase in temperature that occurs in the scrotal sac in the presence of a varicocele may cause dysfunction of the testicular hormonal apparatus, leading to atrophy of the testicle and possibly causing alterations in the maturation of the male gametes that may cause genetic alterations in future mature spermatozoa.

Varicocele as a venous formation "per se" is caused by a dysfunction of the venous circulatory system in which venous stasis and accumulation occurs, forming a mobile and sometimes palpable and painful mass. 

This dysfunction of the venous circulatory system can have many causes, so we will divide the causes of varicocele into primary and secondary causes.

We call primary causes of varicocele all those origins that cause dysfunction by themselves and are the main sources of the disease. In the case of varicocele and its causes, the primary root cause of the dysfunction that provokes the venous accumulation that forms the varicocele has not been clearly demonstrated. It is considered that it is a conglomerate of alterations (multifactorial origin) that makes it difficult for the venous blood that seeks to leave the testicle and the scrotal sac to do so.

In favour of this type of primary origin that causes varicocele, it has been shown that siblings of patients with varicocele have a 4.5 times higher risk of suffering from the disease than those who do not have direct relatives with the disease. This speaks in favour of the association of genetic vascular alterations that may cause this pathological entity.

Within the primary origin as a cause of varicocele, attempts have also been made to find an anatomical explanation as the original cause of the disease. Anatomically, the left spermatic vein has no venous valves. These venous valves, which are found inside the veins, serve to help push the blood upwards as a form of vascular stop which the blood uses to propel itself.

The absence of these valves could favour the stagnation of part of this venous blood, leading to the appearance of varicocele. 

The left spermatic vein flows directly into the left renal vein, a system with much greater pressure than the inferior vena cava, which means that small changes in the pressures of the venous system can cause alterations and dysfunctions in the circulation, as we will explain below.

Secondary causes of varicocele are defined as any entity, disease or circumstance that can cause the secondary creation of a varicocele by its mere formation. In any study of varicocele, the presence of renal carcinoma, peritoneal tumour, peritoneal fibrosis and cirrhosis of the liver must be ruled out, as it has been shown that, although with a very low prevalence, these are diseases that can be associated with the formation of a varicocele.

Renal carcinoma as a cause of varicocele

Renal carcinoma as a cause of varicocele is rare, although it has been shown that in at least 3% of cases of renal carcinoma a varicocele is secondarily associated with the presence of a varicocele.

Renal carcinoma is very rare within the probability of finding neoplasms in the general population (around 2-3% of all neoplasms) although it is the most frequent of all kidney neoplasms (85% of cases). The first symptoms usually appear as haematuria, pain and the finding of an abdominal mass.

The mechanism by which renal carcinoma can cause a varicocele is purely physical. 

The enlarged kidney compresses the left or right renal vein depending on the location of the kidney and this obstruction causes an increase in venous pressure in the inferior vena cava which worsens venous flow. 

The spermatic vein formed by the venous blood leaving the testicle and the pampiniform plexus (origin of the varicocele) flows into the inferior vena cava in the case of the right and into the left renal vein in the case of the left spermatic vein. In the case of the right spermatic vein, which drains directly into the inferior vena cava, this alteration is direct.

In the case of the left spermatic vein, which flows directly into the left renal vein, the effect of a left carcinoma is much more evident on the left side, as subtle changes in the renal vein have a much more direct influence on the left side than on the right, explaining, among other variants, why a left varicocele is much more frequent than a right varicocele. 

As a consequence, an increase in venous stasis in any of its variants causes difficulty in the venous return of the pampiniform plexus, leading to and causing varicocele.

Peritoneal tumour and peritoneal fibrosis as a cause of varicocele

The presence of a peritoneal tumour or peritoneal fibrosis as a cause of varicocele presents a similar mechanism to that explained above with renal carcinoma.

The peritoneum is a sheet of connective tissue that envelops the abdomen, all its vital organs and the blood vessels, lymphatics and nervous system. 

When a tumour of the peritoneum itself or an increase in its thickness, whatever its cause (peritoneal fibrosis) occurs in the lower or medial part of the peritoneum, it can produce a compression mechanism of the inferior vena cava that can lead to dysfunction or difficulty in the venous return of all the circulatory vascular structures below it, including the pampiniform plexus, resulting in a varicocele, in this case, caused by a tumour or peritoneal fibrosis.

Liver cirrhosis as a cause of varicocele

Cirrhosis of the liver as a cause of varicocele has its origin in portal hypertension secondary to cirrhosis of the liver.

Cirrhosis of the liver is a condition characterised by an increase in the hardness of the liver. 

By increasing the hardness of the liver, it causes the structures within the liver to be subjected to more pressure and, in the case of arteries and veins, to increase their internal pressure. This is known in one of the many manifestations that characterise liver cirrhosis as portal hypertension.

The definition of portal hypertension is the increased pressure of the venous circulation transiting the vein with consequent dysfunction of the preceding venous circulatory system. In this case, an increase in portal hypertension can lead to impaired circulation in the inferior vena cava, as we have explained in previous cases, making it possible to form a venous mass in the pampiniform plexus known as a varicocele.

The only definitive option to repair varicocele is surgery. It is a quick and risk-free procedure, so in cases where the symptoms of pain or infertility are severe, it is recommended. To find out more about this surgical procedure, click on the following banner: