manifestations/ presentation of fibromuscular dysplasia☆Fibromuscular webs (luminal stenosis) alternating with areas of aneurysmal dilation
☆Loss of the internal elastic lamina
Most common in women, age <55
IVC(inferior vena cava) obstruction caused by RCC(renal cell carcinoma)IVC obstruction can occur due to intraluminal extension and thrombus formation, rather than mass effect from the tumor itself.
The obstruction can occur acutely or gradually over time. In chronic cases, collateral venous circulation may develop based on the site of the obstruction. Prominent abdominal wall collateral veins(☆tortuous abdominal veins), and ☆symmetric bilateral lower extremity pitting edema suggest obstruction of the upper segment of the IVC. renalanatomyUWorld HirotoShishido
site of the nephron with the lowest osmolarityhigh ADH→ distal convoluted tubule (100mOsm/L)
mechanism of correction of metabolic acidosis by kidney・Increased HCO3- reabsorption
・Increased H+ secretion
・Increased acid buffer excretion: In order to facilitate excretion of much larger amounts of acid, the kidney utilizes acid buffers to trap H+ without markedly lowering urinary pH. The 2 most important acid buffers in urine are ☆hydrogen phosphate (HPO4 2-) and ammonia (NH3). renalendocrinologyUWorld HirotoShishido
which cells experience hyperplasia as a result of renal hypoperfusion?JG cells (☆modified smooth muscle
cells with renin-containing zymogen granules) of the affected kidney(s)to undergo hyperplasia as a result of chronic stimulation
Macula densa cells are tall, narrow cells located in the distal tubule that monitor salt content and tubular flow rate. This information is transmitted to nearby JG cells that are located mainly in the wall of the afferent arteriole. renalUWorld HirotoShishido
renal functions of pregnant womanIncreased blood volume and cardiac output result in the following alterations in renal hemodynamics:
• Increased renal plasma flow (RPF), ☆which peaks at 12 weeks gestation.
• Increased glomerular filtration rate
• Increased creatinine clearance, leading to decreased serum creatinine levels, typically by an average reduction of approximately 0.4 mg/dL renalOBGYUWorld HirotoShishido
non-permeable part of nephron to waterthick&thin ascending limbs of Henle's loop+ early distal convoluted tubule renalUWorld HirotoShishido
why does the patient with heart failure(HF) often have hyperkalemia despite adequete aldosterone formationpatients with HF have low effective arterial volume(EAV) due to third-spacing of retained fluid into the interstium(eg pulmonary, extermity edema)
→low EAV will cause ☆reduced sodium and water delivery to the collecting duct, which impairs sodium/potassium exchange by thn Na-K-ATPase, resulting in hyperkalemia renalcardiologyUWorld HirotoShishido
cause of hypophosphatemia・Internal redistribution
→ especially refeeding malnourished patients
Reintroduction of carbohydrates (ie, dextrose-containing intravenous fluids) increases insulin secretion, which stimulates the ☆redistribution of phosphate from the serum into muscle and hepatic cells for use during glycolysis (eg, formation of ATP, 2-3 diphosphoglycerate)
renal potassium excretion with high dietary
K+ loadbowman's capsule 100%
end of proximal tubule 35%
end of ascending limb of Henle's loop 10%
end of collecting duct 110% renalUWorld HirotoShishido
Renal segment which is damaged first and severely¥straight segment of proximal tubule (PST) and the distal straight tubule (aka thick ascending limb, or TAL) are both located in the outer renal medulla and are the nephron segments damaged first and most severely during renal hypoperfusion. renalAmboss level4 HirotoShishido
normal anion gap metabolic acidosisHARD F ASS
Hyperalimentation
Addison disease
Renal tubular acidosis
Diarrhea
★pancreatic or intestinal Fistula
Acetazolamide
Spironolactone
Saline infusion renalUWorld step2CK HirotoShishido
fanconi syndrome
manifestationpolyuria, polydipsia, and ☆failure to thrive tend to occur in the first years of life
☆Glucose, bicarbonate, amino acids, calcium, and phosphate are normally filtered by the glomerulus and reabsorbed by the proximal tubule. When proximal tubular transport is defective (as in Fanconi syndrome), these substances appear in the urine despite being present at normal concentrations in serum. renalUWorld HirotoShishido
