urinary Flashcards
- Renal corpuscle
* site of plasma filtration found in renal cortex - Renal tubule
* Tube extending from the glomerular
capsule divided into parts
* proximal convoluted tubule
* loop of Henle dips down into medulla
* distal convoluted tubule - Collecting ducts and papillary ducts
* Drain urine to the renal pelvis and ureters
The Normal Nephron
This is dependant on
1. Blood flow
2. Adequate hydration
3. Anatomically normal
function of the urinary tract is to form urine.
- Prerenal
* Due to shock or heart insufficiency (heart attack)
* Usually reversible - Intra renal
* E.g.. Tubular necrosis
* Also reversible
* Chronic failure is lethal, and will lead to dialysis - Post renal
– Prostatic disease
– Stones of the bladder
Both are treated surgically
Failure to produce adequate amount of urine
Renal tubules are very specialized cells therefore sensitive to
lack of O2 and toxins. PCT are the most sensitive to lack of O2
* Many of the cells in the urinary tract are mitotic therefore undergo division. Also may have carcinogens in the urine
Major Kidney Diseases
– Circulatory disturbances (e.g., prerenal renal
failure)
- Hemodynamic Disorders
- Typically occurs after cardiac arrest
and any form of Hypotensive shock
(massive bleeding)
Acute Tubular Necrosis
Atherosclerosis of major arteries (aorta
and major branches of the renal artery)
may lead to decreased lumen and thus
decreased blood flow to kidneys.
– loss of glomeruli, due to ischemic
glomerulosclerosis
– Problem of ischemia
– Tubular atrophy
Nephroangiosclerosis
Arterial hypertension often affects
intrarenal arteries and arterioles
Hypertension
Tumors are more often malignant than
benign.
Neoplasms of the Urinary Tract
Tumor of infancy and childhood
Wilms’ Tumor or
Nephroblastoma
- Lack of early warning signs so tumors are
often far advanced at diagnosis
Renal Cell Carcinoma
Signs and Symptoms
* Hematuria—most common finding (50%)
* Typical triad (hematuria, flank pain, palpable
abdominal mass) found only in 10%
* Nonspecific symptoms (weight loss, fever,
hypertension) common, often found accidentally
(“internist’s tumor”)
* Paraneoplastic syndromes—hypercalcemia,
erythrocytosis, or amyloidosis (20%)
* 5 year survival is only 45%, if tumour is
asymptomatic and small it is 70%
Renal Cell Carcinoma—Clinical
- Most are caused by bacteria
- Bacteria can reach the urinary tract from either
hematogenous infection or more often through an
ascending infection
Hematogenous Infection - Typically preceded by septicemia
- Bacteria spreads through blood from another source to
the urinary tract
Urinary Tract Infections
Ascending Infections
* Most common form
Urinary Tract Infections
results from
bacterial invasion of the renal
parenchyma
* Typically presents with :
– fever, back pain over the kidneys, dysuria,
hematuria, and frequency are possible but
not necessary
Acute Pyelonephritis