Kidney cyst
| Classification according to ICD-10 | |
|---|---|
| N28.1 | Kidney cyst, acquired |
| Q61 | Cystic kidney disease |
| ICD-10 online (WHO version 2019) | |
Under renal cysts is meant individual, liquid-filled and surrounded by a capsule cavities in the parenchyma of the kidney .
The majority of cases are developmental anomalies that can occur sporadically or through heredity . Solitary (single) kidney cysts are located in the renal cortex , whereby smaller cysts usually remain unnoticed for life or can be discovered by chance during an examination ( sonography ). Individual kidney cysts can occur in anyone and are usually harmless. They usually do not cause discomfort and do not require treatment.
Large kidney cysts can become symptomatic, for example with tenderness, due to displacement of the kidney.
Occurrence
Kidney cysts are rare under the age of 50 and their incidence increases with age. Kidney cysts are normally undetectable in healthy individuals under the age of 29, the incidence of at least one kidney cyst between the ages of 30 and 49 is 1.7%, between the ages of 50 and 70 it is 11.5% and over the age of 70 it is 22.1%. The frequency of cysts on both kidneys is 1% between the ages of 30 and 49, 4% between the ages of 50 and 70 and 9% above the age of 70.
Kidney cysts can occur as part of the following diseases:
- Cyst kidney
- Medullary Cystic Kidney Disease Type 1 (MCKD1) and Medullary Cystic Kidney Disease Type 2 (MCKD2)
- Nephronophthisis with small cysts of the renal medulla
- Meckel syndrome
- Hippel-Lindau syndrome
- Birt-Hogg-Dupé syndrome
- Tuberous sclerosis
- Acquired cystic kidney diseases: in <1% of children, mostly solitary and unilateral with a diameter of about 1 cm, mostly asymptomatic, can also occur after prolonged dialysis treatment.
Classification of kidney cysts according to Bosniak
The division of cysts is carried out according to the classification of Bosniak into simple and complicated cysts:
-
Simple cysts (no follow-up required)
- Type I: Benign kidney cyst : fluid-filled, invisible or wafer-thin cyst wall, in the ultrasound sound amplification behind the cyst, no transverse walls (septa), no calcium deposits (calcification) in the cyst wall, no solid parts, in computed tomography and magnetic resonance tomography no contrast enhancement .
- Type II: Benign, minimally complicated cyst : Few, thin septa, fine calcifications in the septa or in the cyst wall. Dense (hyperdense) lesions : thickened, but still homogeneous content, sharply demarcated wall, without contrast agent absorption and without tissue parts (cysts with thickened content accordingly; containing blood breakdown products or proteins).
-
Complicated cysts, follow-up checks required
- Type IIF: Minimal thickening of the cyst wall or septa, thick or granular calcifications, no areas with contrast agent absorption. It will follow-up ( F ollow up) necessary to exclude a change in the properties or a cyst growth.
-
Surgical intervention recommended
- Type III: Thickening of the cyst wall or septa, irregular or granular, possibly with contrast medium uptake in the CT. Malignancy can not be ruled out with this appearance . But it can also be infected or bleeding cysts.
- Type IV: Clearly cystic malignancy (kidney cancer) with irregular, solid, contrast medium-absorbing tissue as a criterion for malignancy.
See also
Individual evidence
- ^ D Ravine et al .: Evaluation of ultrasonographic diagnostic criteria for autosomal dominant polycystic kidney disease . In: Lancet . No. 343 , 1994, pp. 824-827 , PMID 7908078 .
- ^ MA Bosniak: The current radiological approach to renal cysts . In: Radiology . No. 158 , 1986, pp. 1-10 , PMID 3510019 ( radiology.rsnajnls.org ).
