The renal pelvis or pelvis of the kidney is the funnel-like dilated part of the

ureter The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epit ...

in the

kidney The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blo ...

. It is formed by the covnvergence of the

major calyces The renal calyces are chambers of the kidney through which urine passes. The minor calyces surround the apex of the renal pyramids. Urine formed in the kidney passes through a renal papilla at the apex into the minor calyx; two or three minor c ...

, acting as a funnel for urine flowing from the major calyces to the ureter. It has a

mucous membrane A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It i ...

and is covered with

transitional epithelium Transitional epithelium also known as urothelium is a type of stratified epithelium. Transitional epithelium is a type of tissue that changes shape in response to stretching (stretchable epithelium). The transitional epithelium usually appears ...

and an underlying lamina propria of loose-to-dense connective tissue. The renal pelvis is situated within the

renal sinus The renal sinus is a cavity within the kidney which is occupied by the renal pelvis, renal calyces, blood vessels, nerves and fat. The renal hilum extends into a large cavity within the kidney occupied by the renal vessels, minor renal calyces, m ...

alongside the other structures of the renal sinus. The renal pelvis is the location of several kinds of

kidney cancer Kidney cancer, also known as renal cancer, is a group of cancers that starts in the kidney. Symptoms may include blood in the urine, lump in the abdomen, or back pain. Fever, weight loss, and tiredness may also occur. Complications can include sp ...

and is affected by infection in

pyelonephritis Pyelonephritis is inflammation of the kidney, typically due to a bacterial infection. Symptoms most often include fever and flank tenderness. Other symptoms may include nausea, burning with urination, and frequent urination. Complications may ...

Clinical significance

The renal pelvis is the location of several kinds of

and is affected by infection in

. A large "staghorn" kidney stone may block all or part of the renal pelvis. The size of the renal pelvis plays a major role in the grading of hydronephrosis. Normally, the anteroposterior diameter of the renal pelvis is less than 4 mm in

fetus A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal dev ...

es up to 32 weeks of

gestational age In obstetrics, gestational age is a measure of the age of a pregnancy which is taken from the beginning of the woman's last menstrual period (LMP), or the corresponding age of the gestation as estimated by a more accurate method if available. Su ...

and 7 mm afterwards.Page 189
in: In adults, 13% of the normal population have a transverse pelvic diameter of over 10 mm.

Etymology and pronunciation

Like the bony pelvis, the renal pelvis () gets its English name via

New Latin New Latin (also called Neo-Latin or Modern Latin) is the revival of Literary Latin used in original, scholarly, and scientific works since about 1500. Modern scholarly and technical nomenclature, such as in zoological and botanical taxonomy ...

from the older

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

word '' pelvis'', "basin", as in "

wash basin A sink is a bowl-shaped plumbing fixture for washing hands, dishwashing, and other purposes. Sinks have Tap (valve), a tap (faucet) that supply hot and cold water and may include a spray feature to be used for faster rinsing. They also include ...

". In both cases the name reflects the shape of the structure, and in the case of the renal pelvis, it also reflects the function. The name reflects that each renal pelvis collects

urine Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excreted from the body through the urethra. Cellular ...

from the calyces and funnels it into the

like a wash basin collects

water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...

and funnels it into a drain pipe. The renal pelvis is occasionally called the pyelum (from Greek πύελος ''pýelos'', "trough", ‘anything hollow’), and the

combining form Neoclassical compounds are compound words composed from combining forms (which act as affixes or stems) derived from classical Latin or ancient Greek roots. New Latin comprises many such words and is a substantial component of the technical an ...

pyelo- The renal pelvis or pelvis of the kidney is the funnel-like dilated part of the ureter in the kidney. It is formed by the covnvergence of the major calyces, acting as a funnel for urine flowing from the major calyces to the ureter. It has a mucous ...

'' denotes the renal pelvis (''pyelo-'' is not to be confused with '' pyo-''). The words ''

infundibulum An infundibulum (Latin for ''funnel''; plural, ''infundibula'') is a funnel-shaped cavity or organ. Anatomy * Brain: the pituitary stalk, also known as the ''infundibulum'' and ''infundibular stalk'', is the connection between the hypothalamus an ...

'' and ''

choana The choanae (singular choana), posterior nasal apertures or internal nostrils are two openings found at the back of the nasal passage between the nasal cavity and the throat in tetrapods, including humans and other mammals (as well as crocodilia ...

'' are other words for funnel-shaped cavities (which medical English got from the Latin and Greek words for "funnel", respectively), and the renal pelvis is sometimes called the renal infundibulum. The form ''*renal choana'' is logical but is not used.

Additional images

File:Gray1118.png, Depiction of the developing renal pelvis. File:Slide17iii.JPG, Cutaway section of a preserved human kidney

References

External links

* —"Section of the kidney, anterior view." * * —"Mammal, renal pelvis (Gross, Medium)" * —"Mammal, renal pelvis (LM, Medium)" {{Authority control Kidney anatomy

Clinical significance

Etymology and pronunciation

Additional images

See also

References

External links