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Acute tubular necrosis
Renal cortical necrosis
Renal papillary necrosis
IgA nephropathy (NORD)
Rapidly progressive glomerulonephritis
Focal segmental glomerulosclerosis (NORD)
Minimal change disease
Medullary cystic kidney disease
Medullary sponge kidney
Multicystic dysplastic kidney
Polycystic kidney disease
Chronic kidney disease
Renal tubular acidosis
Nephroblastoma (Wilms tumor)
Renal cell carcinoma
Renal artery stenosis
Acid-base disturbances: Pathology review
Congenital renal disorders: Pathology review
Electrolyte disturbances: Pathology review
Kidney stones: Pathology review
Nephritic syndromes: Pathology review
Nephrotic syndromes: Pathology review
Renal and urinary tract masses: Pathology review
Renal failure: Pathology review
Renal tubular acidosis: Pathology review
Renal tubular defects: Pathology review
Urinary incontinence: Pathology review
Urinary tract infections: Pathology review
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‘Hyper-’ means ‘over’ and ‘-magnes-’ refers to magnesium, and -emia refers to the blood, so hypermagnesemia means higher than normal magnesium levels in the blood, and symptoms typically develop at a level over 4 mEq/L.
An average adult has about 25 grams of magnesium in their body.
About half is stored in the bones, and most of the other half is found within cells.
In fact, magnesium is a really common positively charged ion found within the cell, second only to king potassium.
A very tiny fraction, roughly 1% of the total magnesium in the body, is in the extracellular space which includes both the intravascular space - the blood and lymphatic vessels, and the interstitial space - the space between cells.
About 20% of the magnesium in the extracellular space, which would be about 0.2% of the total magnesium, is bound to negatively charged proteins like albumin, but the other 80% or 0.8% of the total magnesium, can be filtered into the kidneys.
So in the kidney, that magnesium gets filtered into the nephron, andi about 30% gets reabsorbed at the proximal convoluted tubule, 60% gets reabsorbed in the ascending loop of Henle, and 5% get reabsorbed at the distal convoluted tubule.
That leaves only 5% to get excreted by the kidneys.
So, in order for there to be too much magnesium in the blood, this normal balance has to be disturbed.
Another cause of hypermagnesemia is ingesting more magnesium than the kidneys can excrete.
Sometimes this can be due to an intravenous infusion of magnesium that isn’t prepared correctly.
If these medications are taken in excess over a long period of time, it can lead to hypermagnesemia.
There are some less common causes of hypermagnesemia.
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