Anion Gap

Category: generalpediatrics-Electrolytes

Findings: methanol, uremia, DKA, paraaldehyde, iron ingestion, lactic acid, ethanol or ethylene glycol, salicylates

Notes: MUDPILES. Should see normal chloride and low bicarbonate

Question: Do these conditions cause an anion gap or non-anion gap metabolic acidosis?

Central Diabetes Insipidus

Category: generalpediatrics-Electrolytes

Findings: hypernatremia, polyuria, dilute urine with low osmolality, treated with DDAVP

Notes: If diagnosis is confirmed obtain brain imaging and pituitary hormones.

Question: What fits these findings?

Cerebral Salt Wasting

Category: generalpediatrics-Electrolytes

Findings: hyponatremia, high urine sodium and osmolality, hypotension, poor skin turgor, seizures

Notes: Similar to SIADH but has a volume-depleted state instead of being euvolemic or hypervolemic

Question: What fits these findings?

Chloride Responsive

Category: generalpediatrics-Electrolytes

Findings: vomiting, dehydration and contraction alkalosis, loop or thiazide diuretics

Notes: You may need to treat with a normal saline bolus, if there is contraction alkalosis. You will see a urine chloride less than 15 as the body is trying to hold onto chloride.

Question: Do these cause a chloride responsive or unresponsive metabolic alkalosis?

Chloride Unresponsive

Category: generalpediatrics-Electrolytes

Findings: Cushing syndrome, hyperaldosteronism, Bartter syndrome, Gitelman syndrome, Liddle syndrome

Notes: Urine chloride is more than 15 as the body as enough chloride.

Question: Do these cause a chloride responsive or unresponsive metabolic alkalosis?

Hypercalcemia

Category: generalpediatrics-Electrolytes

Findings: Williams syndrome, vitamin D or A overingestion, thiazide diuretics, skeletal immobilization, hyperparathyroidism, malignancy

Notes: Will see shortened ST and QT intervals. Bones, stones, abdominal groans and psychiatric moans.

Question: What electrolyte abnormality do these conditions cause?

Hyperkalemia

Category: generalpediatrics-Electrolytes

Findings: kidney failure, aldosterone deficiency, potassium sparing diuretics, rhabdomyolysis

Question: What electrolyte abnormality do these conditions cause?

Hypocalcemia

Category: generalpediatrics-Electrolytes

Findings: respiratory alkalosis, hyperventilation

Question: What electrolyte abnormality does this cause?

Hypocalcemia

Category: generalpediatrics-Electrolytes

Findings: chvostek sign, trousseau sign, tetany, paresthesias

Hypokalemia

Category: generalpediatrics-Electrolytes

Findings: U-waves, flattened T-waves, constipation, weakness

Nephrogenic Diabetes Insipidus

Category: generalpediatrics-Electrolytes

Findings: high urine output, hypernatremia, lack of response to DDAVP, X-linked recessive

Notes: Treat with salt restriction and hydrochlorothiazide

Non-anion Gap

Category: generalpediatrics-Electrolytes

Findings: diarrhea, small bowel fistula, carbonic anhydrase inhibitors such as acetazolamide, rental tubular acidosis, adrenal insufficiency, ureterostomy

Notes: Will see hyperchloremia and low bicarbonate level

Question: Do these conditions cause an anion gap or non-anion gap metabolic acidosis?

Renal Tubular Acidosis Type 1

Category: generalpediatrics-Electrolytes

Findings: hypokalemia, caused by inability to excrete hydrogen ions, urine pH more than 5.5, associated with autoimmune conditions

Renal Tubular Acidosis Type 2

Category: generalpediatrics-Electrolytes

Findings: hypokalemia, caused by loss of bicarbonate in urine, urine pH less than 5.5

Renal Tubular Acidosis Type 4

Category: generalpediatrics-Electrolytes

Findings: hyperkalemia, urine pH less than 5.5, seen in hypoaldosteronism and diabetes

Syndrome Of Inappropriate ADH Secretion (SIADH)

Category: generalpediatrics-Electrolytes

Findings: increased total body water, low urine output, low serum osmolality, hyponatremia, high urine osmolarity and sodium, treated with fluid restriction

Notes: If persists despite fluid restriction, treat with diuretic or fludrocortisone. Kidney is holding onto water but losing sodium as there is a hypervolemic state.