Autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease
Most common genetic renal disease 1:1000 affected. 4-6 million worldwide. It is also known as polycystic kidney syndrome. It is a progressive, ciliopathic, genetic disorder of the kidneys. It is characterized by the presence of multiple cysts (hence, "polycystic") in both kidneys. The disease can...

Calyx (singular) or calyces

The recesses in the internal medulla which hold the pyramids. They are used to subdivide the sections of the kidney.


The outer layer over the internal medulla. It contains blood vessels, glomeruli (which are the kidneys' "filters") and nephrons which are supported by a fibrous matrix.

Diffuse proliferative lupus nephritis

Diffuse proliferative lupus nephritis
Lupus nephritis is an inflammation of the kidney caused by systemic lupus erythematosus (SLE), a disease of the immune system. Apart from the kidneys, SLE can also damage the skin, joints, nervous system and virtually any organ or system in the body. Image courtesy of...

Ectopic kidney

An abnormal location of the kidney, usually in the pelvis. This may cause ureteral obstruction resulting in renal damage and kidney stone formation. It affects 1 in 800.


The opening in the middle of the concave medial border for nerves and blood vessels to pass into the renal sinus.

Horseshoe kidney

Horseshoe kidney
Affects 1 in 400. The kidneys are fused in the midline. It is generally lower than normal. It may be associated with ureteral obstruction and kidney stone formation. Image courtesy of This image is in the public domain


Underdevelopment or incomplete development of a tissue or organ. One or both kidneys are small in size. Prone to infection and kidney stone formation.


Also called floating kidney. It is an inferior displacement of the kidney which occurs when the kidney slips from its normal position because it is not securely held in place by adjacent organs. This causes the kink of the ureter and blockage of urine flow.

Papilla (singular) or papillae

The small conical projections along the wall of the renal sinus. They have openings through which urine passes into the calyces.

Renal agenesis

Failure to develop kidneys occurs in about 1 in every 2500 foetuses, and is not compatible with life (associated with pulmonary hypoplasia it is known as Potter’s syndrome. More common in infants born of a parent who has a kidney malformation. It is genetically related. Most infants that are born...

Renal artery

Two renal arteries come from the aorta, each connecting to a kidney. The artery divides into five branches, each of which leads to a ball of capillaries. The arteries supply (unfiltered) blood to the kidneys. The left kidney receives about 60% of the renal bloodflow.

Renal capsule

The membranous covering of the kidney.

Renal column

The structures which support the cortex. They consist of lines of blood vessels and urinary tubes and a fibrous material.

Renal pelvis

 Basically just a funnel, the renal pelvis accepts the urine and channels it out of the hilus into the ureter.

Renal pyramids

The conical segments within the internal medulla. They contain the secreting apparatus and tubules and are also called malpighian pyramids.

Renal sinus

The cavity which houses the renal pyramids.

Renal vein

The filtered blood returns to circulation through the renal veins which join into the inferior vena cava (IVC) 

Unilateral agenesis

Only one kidney is developed and affects about 1 in 1000 of the population. The single kidney becomes hypertrophied, and may be in a wrong location. Easy to get infected and damaged