Kidney Infections and Inflammation Notes

Kidney Infections and Inflammation

Pyelonephritis

• Ascending infection of the kidneys (starts low, rises up the hypervolemiat).

• May affect one or both kidneys.

• Can be acute or chronic (recurrent or long-term).

• Symptoms:

  • Flank pain (mid-back pain).

  • High fever and chills.

  • Confusion.

  • Nausea and vomiting.

  • Hematuria (blood in urine).

• Urinalysis:

  • Leukocytes (white blood cells).

  • Nitrate.

  • Protein in the urine.

  • Culture.

• Abnormal findings: white blood cells, nitrate, and protein in the urine.

• Most common causative organism: E. coli.

Acute Glomerulonephritis

• Secondary immune response by the kidneys following an acute beta-hemolytic strep infection.

• Strep infection: typically an upper respiratory infection or middle ear infection (most commonly strep throat).

• Other causes: variety of other types of infections and autoimmune disorders.

• Inflammatory response in the kidneys is triggered by activation of the complement by formation of an antigen-antibody complex that lodges in the glomeruli of the kidneys.

• Large amounts of red blood cells and protein leak into the urine (abnormal finding).

• Damage to the kidneys decreases the glomerular filtration rate.

• Symptoms begin 7-21 days after a strep infection.

• Damage to glomerular capillaries causes protein (including albumin) to leave the blood and be excreted in the urine (proteinuria).

• Less protein in the blood (hypoalbuminemia).

• Albumin is crucial for fluid balance (full force of oncotic pressure).

• $Hypoalbuminemia$: "Hypo" = low, "albumin" = albumin, "emia" = in the blood.

• Hydrostatic pressure is greater than oncotic pressure, causing fluid to be pushed out of the blood vessel into the tissues, resulting in edema (e.g., facial edema).

• Low glomerular filtration rate due to kidney damage.

• Oliguria: "Olig" = very little, "uria" = urine (very little urine).

• The body holds on to more fluid, leading to fluid overload, edema, and hypertension.

• Hematuria: "Hemat" = blood, "uria" = urine (blood in the urine), causing dark cola-colored urine.

• Most individuals recover without significant loss of renal function or recurrence, but renal failure and death can result.

Nephrotic Syndrome

• Combination of clinical findings that occur as the glomeruli are damaged.

• Proteinuria (protein in the urine) and low oncotic pressure causing edema.

• One of the common causes is glomerulonephritis.

• Primary cause is diabetes, specifically diabetic nephropathy from diabetes mellitus.

• Other common causes include lupus, amyloidosis, and glomerulonephritis.

• Symptoms are the same as glomerulonephritis.

• Glomerulonephritis specifically is caused by strep infection (symptoms start 7-21 days after).

• Nephrotic syndrome is caused by reasons other than just glomerulonephritis (e.g., diabetes, lupus, amyloidosis).

Polycystic Kidney Disease

• Genetic disorder affecting the kidneys and other organs due to the development of cysts in the renal tissue.

• Renal function is impaired, and cysts can develop in other organs (e.g., the liver).

• Symptoms include:

  • Pain from the pressure of the fluid in the cysts.

  • Renal calculi (kidney stones).

  • Hematuria (blood in the urine).

• Pressure from cysts near blood vessels blocks blood flow, which stimulates the RAAS system, leading to more volume and hypertension.

• Kidneys aren't getting perfusion because of the cyst putting pressure on the blood vessels and limiting the amount of blood that's coming through them.

• Kidney still kicks on the RAAS system and you end up having too much volume (hypervolemia) and with too much volume, your blood pressure is going to rise as well and so you'll have hypertension.