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Author2 Posts
  #1

I need some help with the fallowing question...

mother notes in her 1-month-old baby girl clear fluid in the umbilicus. She brings this to the attention of her pediatrician, who not only verifies the presence of the fluid but also palpates a midline mass. At surgery a cystic mass is noted that connects to the urinary bladder. What is the most likely diagnosis?




Answer Choices Correct answer Your answer
A. A
B. B
C. C
D. D
E. E
F. F
Explanation
Option D is correct. In congestive heart failure, the cardiac output is decreased and the kidney reabsorbs a slightly hypotonic fluid producing hyponatremia (↓ serum Na+ = ↑TBNa+/↑↑TBW). An increase in total body sodium (TBNa+) is clinically manifested by weight gain, dependent pitting edema, and body effusions. Since POsm and serum Na+ parallel each other, hyponatremia produces a decreased POsm; therefore, the overall height of the interrupted squares is decreased. Since excess fluid is being added to the ECF compartment (primarily the interstitial space), the ECF compartment is expanded. Hyponatremia establishes an osmotic gradient causing water to shift from the ECF into the ICF compartment causing expansion of that compartment as well. This emphasizes the importance of restricting water and sodium in heart failure and using diuretics to eliminate excess sodium and water. Other edema states that can be associated with schematic D are cirrhosis and the nephrotic syndrome.

Option A is incorrect. A represents an isotonic loss of fluid (e.g., secretory diarrhea in cholera and traveler’s diarrhea; loss of whole blood). Serum sodium remains normal (also POsm) when equal amounts of water and sodium are lost (↔serum Na+ = ↓TBNa+/↓TBW). Only the ECF compartment is contracted. A decrease in TBNa+ produces signs of volume depletion (hypotension, dry mucous membranes, tenting of the skin). There is no osmotic gradient; therefore, the ICF compartment is normal.

Option B is incorrect. Schematic B occurs when there is a hypertonic loss of fluid (e.g., diuretics, Addison’s disease, 21-hydroxylase deficiency). Loss of hypertonic fluid produces a hyponatremia (↓serum Na+ = ↓↓TBNa+/↓TBW). Since fluid is lost, the ECF compartment is contracted. Hyponatremia establishes an osmotic gradient; therefore, water shifts into the ICF compartment.

Option C is incorrect. Schematic C occurs when there is an isotonic gain of fluid (e.g., excessive infusion of normal (0.9&percntwink saline. The serum sodium remains normal (↔serum Na+ = ↑TBNa+/↑TBW); therefore, the POsm is normal. Since fluid is being added to the ECF, it is expanded. There is no osmotic gradient; therefore, the ICF remains normal. The treatment is diuretics.

Option E is incorrect. Schematic E occurs when there is a hypotonic loss of sodium (e.g., sweating, osmotic diuresis, glucosuria). The serum sodium is increased (hypernatremia; ↑ serum Na+ = ↓TBNa+/↓↓TBW), causing an increase in POsm and an increase in the height of the interrupted squares. Since fluid is being lost, the ECF compartment is contracted. Hypernatremia establishes an osmotic shift; therefore, water moves out of the ICF compartment.
F is incorrect. Schematic F occurs when there is a hypertonic gain of sodium (e.g., excessive infusion of sodium bicarbonate; infusion of a sodium containing antibiotic). The serum sodium is increased (hypernatremia; ↑ serum Na+ = ↑↑TBNa+/↑TBW), causing an increase in POsm and an increase in the height of the interrupted squares. Since fluid is being added, the ECF compartment is expanded (pitting edema; body effusions). Hypernatremia establishes an osmotic shift; therefore, water moves out of the ICF compartment.





  #2

I think it should be persistent urachus...!!!





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