CT scan

computed tomographyCTCT scans
There is a higher risk of mortality in those who are female, elderly or in poor health, usually secondary to either anaphylaxis or acute renal failure. The contrast agent may induce contrast-induced nephropathy. This occurs in 2 to 7% of people who receive these agents, with greater risk in those who have preexisting kidney failure, preexisting diabetes, or reduced intravascular volume. People with mild kidney impairment are usually advised to ensure full hydration for several hours before and after the injection. For moderate kidney failure, the use of iodinated contrast should be avoided; this may mean using an alternative technique instead of CT.

Collecting duct system

collecting ductcortical collecting ductcollecting ducts
In the absence of ADH, water in the renal filtrate is left alone to enter the urine, promoting diuresis. When ADH is present, aquaporins allow for the reabsorption of this water, thereby inhibiting diuresis. "Collecting Duct (Kidney)". – "Urinary System: kidney, medulla, collecting duct and ascending tubule". – "Urinary System: kidney, H&E, collecting duct and ascending tubule".


podocytesfiltration slitsslit diaphragm
When infants are born with certain defects in these proteins, such as nephrin and CD2AP, their kidneys cannot function. People have variations in these proteins, and some variations may predispose them to kidney failure later in life. Nephrin is a zipper-like protein that forms the slit diaphragm, with spaces between the teeth of the zipper, big enough to allow sugar and water through, but too small to allow proteins through. Nephrin defects are responsible for congenital kidney failure. CD2AP regulates the podocyte cytoskeleton and stabilizes the slit diaphragm. Podocytes are found lining the Bowman's capsules in the nephrons of the kidney.

Renal blood flow

renal plasma flowblood flow to the kidneykidney blood flow
Renal plasma flow is the volume of plasma that reaches the kidneys per unit time. Renal plasma flow is given by the Fick principle: This is essentially a conservation of mass equation which balances the renal inputs (the renal artery) and the renal outputs (the renal vein and ureter). Put simply, a non-metabolizable solute entering the kidney via the renal artery has two points of exit, the renal vein and the ureter.

Pleural cavity

pleuralpleural spacepleura
Transudative pleural effusions occur in congestive heart failure (CHF), cirrhosis or nephrotic syndrome. Localized pleural fluid effusion noted during pulmonary embolism (PE) results probably from increased capillary permeability due to cytokine or inflammatory mediator release from the platelet-rich thrombi. When accumulation of pleural fluid is noted, cytopathologic evaluation of the fluid, as well as clinical microscopy, microbiology, chemical studies, tumor markers, pH determination and other more esoteric tests are required as diagnostic tools for determining the causes of this abnormal accumulation. Even the gross appearance, color, clarity and odor can be useful tools in diagnosis.

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, major renal calyces, renal pelvis and some adipose tissue.

Ascending limb of loop of Henle

thick ascending limbthin ascending limbthick ascending limb of loop of Henle
The thin ascending limb is found in the medulla of the kidney, and the thick ascending limb can be divided into a part that is in the renal medulla and a part that is in the renal cortex. The ascending limb is much thicker than the descending limb. At the junction of the thick ascending limb and the distal convoluted tubule are a subset of 15-25 cells known as the macula densa that are part of renal autoregulation through the mechanism of tubuloglomerular feedback. As in the descending limb, the epithelium is simple squamous epithelium. The thin ascending limb is impermeable to water; but is permeable to ions allowing for some sodium reabsorption.

Retroperitoneal space

retroperitoneumretroperitonealretro-peritoneal organs
Primarily retroperitoneal, meaning the structures were retroperitoneal during the entirety of development:. urinary. adrenal glands. kidneys. ureter. circulatory. aorta. inferior vena cava. anal canal. Secondarily retroperitoneal, meaning the structures initially were suspended in mesentery and later migrated behind the peritoneum during development. the duodenum, except for the proximal first segment, which is intraperitoneal. ascending and descending portions of the colon (but not the transverse colon, sigmoid and the cecum). pancreas, except for the tail, which is intraperitoneal. Adrenal gland. Kidney. Renal vessels. Pancreas. Ascending and descending colon. duodenum.


Hyponatraemialow blood sodiumlow blood sodium levels
This is particularly the case in men and in the elderly. * cirrhosis of the liver. congestive heart failure. nephrotic syndrome in the kidneys. Excessive drinking of fluids. SIADH (and its many causes). Hypothyroidism. Not enough ACTH. Beer potomania. Normal physiologic change of pregnancy. Reset osmostat. any cause of hypovolemia such as prolonged vomiting, decreased oral intake, severe diarrhea. diuretic use (due to the diuretic causing a volume depleted state and thence ADH release, and not a direct result of diuretic-induced urine sodium loss).


hyperlipoproteinemiahyperlipidaemiaPrimary hyperlipoproteinemia
Kidney failure. Nephrotic syndrome. Alcohol consumption. Some rare endocrine disorders and metabolic disorders. List of xanthoma variants associated with hyperlipoproteinemia subtypes. Combined hyperlipidemia.

Aquaporin 2

AQP2 is found in the apical cell membranes of the kidney's collecting duct principal cells and in intracellular vesicles located throughout the cell. It is the only aquaporin regulated by vasopressin. The basic job of aquaporin 2 is to reabsorb water from the urine while its being removed from the blood by the kidney. Aquaporin 2 is in kidney epithelial cells and usually lies dormant in intracellular vesicle membranes. When it is needed, vasopressin binds to the cell surface vasopressin receptor thereby activating a signaling pathway that causes the aquaporin 2 containing vesicles to fuse with the plasma membrane, so the aquaporin 2 can be used by the cell.

Intermediate mesoderm

intermediate cellintermediate cell mass
The intermediate mesoderm will eventually develop into the kidney and parts of both male and female reproductive systems. Early kidney structures include the pronephros and mesonephros, whose complexity, size and duration can vary greatly between vertebrate species. The adult kidney, also referred to as the metanephric kidney, forms at the posterior end of the intermediate mesoderm after the degeneration of previous, less complex kidney structures. During early development (approximately day 22 in humans), the pronephric duct forms from the intermediate mesoderm, ventral to the anterior somites.

Renal hilum

Hilum of kidneyhilumhila of kidneys
The superior, middle, and inferior vessels enter or leave the hilum of kidney: from anterior to posterior is renal vein, renal artery and renal pelvis, respectively. * Renal artery. Renal vein. Renal pyramids. Renal medulla.

Atrial natriuretic peptide

atrial natriuretic factorANPAtriopeptin
Receptor-agonist binding causes the increase in renal sodium excretion, which results in a decreased ECF and blood volume. Secondary effects may be an improvement in cardiac ejection fraction and reduction of systemic blood pressure. ANP acts on the kidney to increase sodium and water excretion (natriuresis) in the following ways: ANP has the opposite effect of angiotensin II on the kidney: angiotensin II increases renal sodium retention and ANP increases renal sodium loss. * Reduces aldosterone secretion by the zona glomerulosa of the adrenal cortex.

Thoracic diaphragm

The thoracic diaphragm, or simply the diaphragm, is a sheet of internal skeletal muscle in humans and other mammals that extends across the bottom of the thoracic cavity. The diaphragm separates the thoracic cavity, containing the heart and lungs, from the abdominal cavity and performs an important function in respiration: as the diaphragm contracts, the volume of the thoracic cavity increases, creating a negative pressure there, which draws air into the lungs.


amyloid degenerationamyloidosesfamilial amyloidosis
The kidney and heart are the most common organs involved. Amyloid deposition in the kidneys can cause nephrotic syndrome, which results from a reduction in the kidney's ability to filter and hold on to proteins. The nephrotic syndrome occurs with or without elevations in creatinine and blood urea concentration, two biochemical markers of kidney injury. In AA amyloidosis, the kidneys are involved in 91–96% of people, symptoms ranging from protein in the urine to nephrotic syndrome and rarely chronic kidney disease. Amyloid deposition in the heart can cause both diastolic and systolic heart failure.


erythropoieticerythropoeisisproduction of red blood cells
Erythropoietin is produced in the kidney and liver in response to low oxygen levels. In addition, erythropoietin is bound by circulating red blood cells; low circulating numbers lead to a relatively high level of unbound erythropoietin, which stimulates production in the bone marrow. Recent studies have also shown that the peptide hormone hepcidin may play a role in the regulation of hemoglobin production, and thus affect erythropoiesis. The liver produces hepcidin. Hepcidin controls iron absorption in the gastrointestinal tract and iron release from reticuloendothelial tissue.

Sympathetic nervous system

sympatheticsympathetic nervesympathetic nerves
The synthesis and release of epinephrine as opposed to norepinephrine is another distinguishing feature of chromaffin cells compared to postganglionic sympathetic neurons. 3) Postganglionic sympathetic nerves terminating in the kidney release dopamine, which acts on dopamine D1 receptors of blood vessels to control how much blood the kidney filters. Dopamine is the immediate metabolic precursor to norepinephrine, but is nonetheless a distinct signaling molecule. Epinephrine. History of catecholamine research. Limbic system. Norepinephrine. Sympathetic ganglia. Sympathetic trunk.

Afferent arterioles

afferent arterioleafferent
If the afferent arterioles are constricted then the blood pressure in the capillaries of the kidneys will drop. Efferent arteriole. Tubuloglomerular feedback. Macula densa. - "Renal Vasculature: Efferent Arterioles & Peritubular Capillaries". - "Mammal, renal vasculature (EM, Low)".

Endocrine system

endocrineendocrinologicalendocrine organ
In addition to the specialized endocrine organs mentioned above, many other organs that are part of other body systems, including bone, kidney, liver, heart and gonads, have secondary endocrine functions. For example, the kidney secretes endocrine hormones such as erythropoietin and renin. Hormones can consist of either amino acid complexes, steroids, eicosanoids, leukotrienes, or prostaglandins. The endocrine system can be contrasted to both exocrine glands, which secrete hormones to the outside of the body using ducts and paracrine signalling between cells over a relatively short distance.

Transversalis fascia

transverse fasciafascia transversalis
Behind, it is lost in the fat which covers the posterior surfaces of the kidneys. Below, it has the following attachments: posteriorly, to the whole length of the iliac crest, between the attachments of the transverse abdominal and Iliacus; between the anterior superior iliac spine and the femoral vessels it is connected to the posterior margin of the inguinal ligament, and is there continuous with the iliac fascia. Medial to the femoral vessels it is thin and attached to the pubis and pectineal line, behind the inguinal falx, with which it is united; it descends in front of the femoral vessels to form the anterior wall of the femoral sheath.

Tamm–Horsfall protein

Tamm-Horsfall proteinUMODuromodulin
THP may also be important in protection from kidney injury by down-regulating inflammation. Uropontin, nephrocalcin and uromodulin (this protein) are the three known urinary glycoproteins that affect the formation of calcium-containing kidney stones or calculus. Tamm–Horsfall protein is part of the matrix in renal calculi but a role in kidney stone formation remains debatable. However, decreased levels of Tamm–Horsfall in urine have been found to be a good indicator of kidney stones. Defects in this gene are associated with the autosomal dominant renal disorders medullary cystic kidney disease-2 (MCKD2) and familial juvenile hyperuricemic nephropathy (FJHN).


hypercoagulabilityhypercoagulable statehypercoagulable
Nephrotic syndrome, in which protein from the bloodstream is released into the urine due to kidney diseases, can predispose to thrombosis; this is particularly the case in more severe cases (as indicated by blood levels of albumin below 25 g/l) and if the syndrome is caused by the condition membranous nephropathy. Inflammatory bowel disease (ulcerative colitis and Crohn's disease) predispose to thrombosis, particularly when the disease is active. Various mechanisms have been proposed. Pregnancy is associated with an increased risk of thrombosis. This probably results from a physiological hypercoagulability in pregnancy that protects against postpartum hemorrhage.

Parasympathetic nervous system

parasympatheticparasympathetic nerveparasympathetic nerves
From these four ganglia the parasympathetic nerves complete their journey to target tissues via trigeminal branches (ophthalmic nerve, maxillary nerve, mandibular nerve). 2) The vagus nerve does not participate in these cranial ganglia as most of its parasympathetic fibers are destined for a broad array of ganglia on or near thoracic viscera (esophagus, trachea, heart, lungs) and abdominal viscera (stomach, pancreas, liver, kidneys, small intestine, and about half of the large intestine).

Muehrcke's nails

Muehrcke's linesMuehrcke lines
The appearance of Muehrcke's lines is associated specifically with marked hypoalbuminemia (serum albumin ≤ 2.2 g/dL) indicating decreased protein synthesis, which may occur during periods of metabolic stress (e.g. systemic infection, trauma, AIDS, chemotherapy), or in hypoalbuminemic states such as the nephrotic syndrome or dietary protein deficiency. They are also seen in patients with end-stage kidney disease on hemodialysis, Hodgkin's disease, pellagra, and sickle cell anaemia. The lines remain visible as long as protein intake is inadequate or synthesis is impaired, and they should disappear upon return to normal function.