Adrenal cyst in adults and children

A cavity in the adrenal endocrine glands limited by a capsule - an adrenal cyst - is a rare pathology and is often completely unexpectedly detected during imaging (during ultrasound or computed tomography). This gave grounds to classify cysts of this localization as incidentalomas, that is, accidentally identified tumor-like formations. According to ICD-10 code E27.8 (other disorders of the adrenal glands).[1]

Epidemiology

When examining the organs of the abdominal and abdominal cavity using computed or magnetic resonance imaging, in 4-5% of patients, random findings in the form of various formations of the adrenal glands, called incidentalomas by specialists, are revealed. Moreover, most often these are adenomas (more than 67%) and cystic lesions (9.7%). Endothelial or lymphangiomatous cysts account for almost 45% of these lesions and are usually small in size, 0.1 to 1.5 cm in diameter. Pseudocysts of the adrenal gland without epithelial lining are the next most common type (39%) and most likely represent the encapsulated remnants of previous hemorrhages in the adrenal glands.

However, according to the data of clinical surgery, among the pathologies of this localization, the share of cysts falls on 0.68% of cases.

According to statistics, the most common adrenal cysts are endothelial (from 2 to 24% of cases), and the most rare is parasitic echinococcal (0.5%).

Most often, the formation is unilateral, that is, a cyst of the right adrenal gland or the left.

Moreover, the adrenal cyst in men is found three times less often than in women. [2], [3]

Causes adrenal cysts

As in many cases of abdominal cystic lesions, specialists often fail to establish the cause of adrenal cysts. But among the versions of their origin, first of all, there are congenital anomalies of embryogenesis of the tissues of the cortex and medulla of the adrenal glands and the injuries of the abdominal region affecting them.[4]

Adrenal cysts are divided into:

• an epithelial or true cyst with a clearly distinguishable membrane lined with epithelium;
• endothelial or vascular cysts - lymphangiomatous (lymphangiectatic) and hemangiomatous (angiomatous);
• a pseudocyst or hemorrhagic cyst, which occurs either as a result of a hematoma, or forms in  adrenal tumors  (benign or malignant) - as part of them.

A parasitic cyst of the adrenal gland is also allocated - when the gland is damaged by the larvae of  Echinococcus  (Echinococcus granulosus).[5]

In children, the adrenal cyst is not only vascular, [6]but can also be pseudocyst: with a tumor in the adrenal medulla -  pheochromocytoma , cystic neuroblastoma or  teratoma .[7]

An adrenal cyst in a newborn belongs to congenital anomalies, and can also be the result of a birth injury - perinatal hemorrhage, that is, hemorrhage in the adrenal glands. [8]

In addition, adrenal hemorrhage in adults is possible with shock, trauma, meningococcal septicemia,  disseminated intravascular coagulation syndrome (DIC) .

Risk factors

In the same way, specific risk factors for the occurrence of an adrenal cyst have not been identified, although, according to foreign studies, some conditions and diseases have been identified in which these formations are often found.

So, adrenal cysts are detected in patients with refractory arterial hypertension, polycystic and kidney cancer, an aneurysm of the abdominal aorta, a pancreatic cyst (then a cyst of the left adrenal gland is found), with congenital  Klippel-Trenone syndrome  and some other genetically determined anoregiasis, for example, cerebrovascular accidents.

It is extremely rare for an adrenal cyst in women to be accidentally detected by ultrasound during pregnancy or as a metastasis of a malignant breast tumor.

Pathogenesis

It is believed that the pathogenesis of a vascular lymphangiomatous cyst is associated with an ectatic change (dilation) of lymphatic vessels in the adrenal medulla or cystic degeneration of an existing nodular benign formation - mesenchymal hamartoma. And pathological changes or abnormalities of small blood vessels of the adrenal gland, including aneurysms and hemorrhage of the adrenal veins, lead to the formation of angiomatous cysts.

An epithelial cyst develops from cells of the embryonic tissue - mesenchyme and is a consequence of intrauterine developmental disorders.

The mechanism of formation of adrenal cysts with foci of primary neoplasms of these glands (adenoma of the adrenal cortex, carcinoma or pheochromocytoma) is unclear.

Symptoms adrenal cysts

As experts note, an accidentally detected adrenal cyst rarely causes symptoms: most of these formations, especially epithelial cysts, are asymptomatic (and do not need treatment).

The first signs in the form of pain in the abdomen or side and gastrointestinal disorders appear when the cyst is large: it can be detected by palpation. A lymphangiomatous cyst can be of such a size that it can partially or completely replace the adrenal gland.[9]

A palpable mass in the abdominal region, anemia and jaundice are observed with adrenal cysts in infants.

Symptoms of an echinococcal cyst include general ill health and weakness, lack of appetite, fever, constant dull pain in the hypochondrium.

Complications and consequences

The main complications and consequences of cystic formations in the adrenal glands: compression of the surrounding vessels and tissues, infection and development of inflammation, bleeding, rupture of the cyst with hemorrhage and shock. [10]

Diagnostics adrenal cysts

In addition to examination and anamnesis, the diagnosis of a cyst of the adrenal endocrine glands requires laboratory tests. Required: clinical and biochemical blood tests; to exclude hormonally active (functional) formations - blood tests are taken for the serum level of adrenal hormones (cortisol, ACTH, aldosterone, renin); general and daily urine analysis - for metanephrine and catecholamine metabolites. A blood test for eosinophils and antibodies to Echinococcus granulosus is also needed.

Instrumental diagnostics includes ultrasound, CT and MRI.

An adrenal cyst on ultrasound of the abdominal cavity appears as a homogeneous hypoechoic structure with smooth contours. However, in adults, the adrenal glands are often poorly visualized on ultrasound.

The cyst of the adrenal gland is more clearly visible on CT, and this method makes it possible to determine the density of the formation, the thickness of the walls of the capsule, internal septa, contents, calcification (detected by 15-30% of cysts), the state of the surrounding tissues. For the purpose of differentiation, computed tomography with contrast and MRI is performed.

Differential diagnosis

Differential diagnosis should take into account the possibility of hyperplasia and adenoma of the adrenal cortex, pheochromocytoma with cystic changes, adrenocortical carcinoma, myelolipoma, etc.

Treatment adrenal cysts

With a large cyst (more than 4-5 cm), as well as with symptoms, surgical treatment is performed. This is a resection or laparoscopic removal of the adrenal cyst. See -  Removing a cyst [11]

In addition, the decompression of the cyst is carried out by percutaneous fine-needle aspiration of its contents (followed by its examination). But there is a high probability of repeated accumulation of fluid in the cystic cavity.[12]

Laparoscopic removal of the cyst membrane (decortication), marsupialization, puncture sclerosis of the cavity with ethanol can be performed. [13]

In cases of pseudocysts with foci of primary adenoma of the adrenal cortex or carcinoma, laparoscopic adrenalectomy is used.

Small, asymptomatic cystic lesions should be monitored regularly by ultrasound or CT and tested for adrenal hormone levels. [14]

After the removal of the parasitic cyst, drugs of the anthelmintic group are prescribed:  Medizol  (Albendazole) or  Vermox  (Mebendazole).

Read also:

• Cyst treatment
• Alternative treatment for cysts

Prevention

Special preventive measures for adrenal cysts have not been developed.

Forecast

For the vast majority of accidentally diagnosed benign adrenal cysts, the prognosis is favorable.