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Old 09-04-2012
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Default Hypokalemia

A 20 yr old Caucasian woman comes to the physician because of weakness, fatigue, polyuria and polydipsia.She has had these symptoms for the past 3 months.She has no other medical problems.She has smoked one pack of cigarettes daily for 2 years,drinks alcohol on weekends, and denies illicit drugs use.Her mother has diabetes .Her father died of a myocardial infarction at the age of 40 years.Her temp is 37.2(99F),BP 110/70 mmHg, and pulse is 74/min.Lab studies reveal:

Serum NA 140mEq/L
Serum K 2.2mEq/L
Bicarbonate 4.2mEq/L
Blood glucose 90 mg/L
Aldosterone Elevated
Renin activity Elevated

The urine assay for diuretics is negative. Urine chloride conc is 60 mEq/L (normal is =20mEq/L).Which of the following is the most likely diagnosis ?

A. Primary hyperaldosteronism
B. Diuretic abuse
C. Bartter syndorme
D. Surreptitous vomiting
E. Renin-secreting tumor
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Old 09-04-2012
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Originally Posted by step_enhancer View Post
A 20 yr old Caucasian woman comes to the physician because of weakness, fatigue, polyuria and polydipsia.She has had these symptoms for the past 3 months.She has no other medical problems.She has smoked one pack of cigarettes daily for 2 years,drinks alcohol on weekends, and denies illicit drugs use.Her mother has diabetes .Her father died of a myocardial infarction at the age of 40 years.Her temp is 37.2(99F),BP 110/70 mmHg, and pulse is 74/min.Lab studies reveal:

Serum NA 140mEq/L
Serum K 2.2mEq/L
Bicarbonate 4.2mEq/L
Blood glucose 90 mg/L
Aldosterone Elevated
Renin activity Elevated

The urine assay for diuretics is negative. Urine chloride conc is 60 mEq/L (normal is =20mEq/L).Which of the following is the most likely diagnosis ?

A. Primary hyperaldosteronism
B. Diuretic abuse
C. Bartter syndorme
D. Surreptitous vomiting
E. Renin-secreting tumor
Oh gosh!!!! Uhhhhh..... I say E.
Bartter has low potassium but they have alkalosis. This question is terrible
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Old 09-04-2012
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Quote:
Originally Posted by step_enhancer View Post
A 20 yr old Caucasian woman comes to the physician because of weakness, fatigue, polyuria and polydipsia.She has had these symptoms for the past 3 months.She has no other medical problems.She has smoked one pack of cigarettes daily for 2 years,drinks alcohol on weekends, and denies illicit drugs use.Her mother has diabetes .Her father died of a myocardial infarction at the age of 40 years.Her temp is 37.2(99F),BP 110/70 mmHg, and pulse is 74/min.Lab studies reveal:

Serum NA 140mEq/L
Serum K 2.2mEq/L
Bicarbonate 4.2mEq/L
Blood glucose 90 mg/L
Aldosterone Elevated
Renin activity Elevated

The urine assay for diuretics is negative. Urine chloride conc is 60 mEq/L (normal is =20mEq/L).Which of the following is the most likely diagnosis ?

A. Primary hyperaldosteronism
B. Diuretic abuse
C. Bartter syndorme
D. Surreptitous vomiting
E. Renin-secreting tumor
Nice question, r u sure bicarbonate is 4.2?
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Originally Posted by Dr_Laura View Post
Oh gosh!!!! Uhhhhh..... I say E.
Bartter has low potassium but they have alkalosis. This question is terrible
If the pt. have E we need to see high blood pressure
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You're right... The Bicarb is

Bartters?
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Sorry Bicarbonate is 42 mEg/L
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C. Bartter syndorme

Quote:
Bartter's syndrome consists of hypokalaemia, alkalosis, normal to low blood pressures, and elevated plasma renin and aldosterone. Numerous causes of this syndrome probably exist. Diagnostic pointers include high urinary potassium and chloride despite low serum values, increased plasma renin, hyperplasia of the juxtaglomerular apparatus on renal biopsy, and careful exclusion of diuretic abuse. Excess production of renal prostaglandins is often found. Magnesium wasting may also occur.
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Quote:
Originally Posted by step_enhancer View Post
A 20 yr old Caucasian woman comes to the physician because of weakness, fatigue, polyuria and polydipsia.She has had these symptoms for the past 3 months.She has no other medical problems.She has smoked one pack of cigarettes daily for 2 years,drinks alcohol on weekends, and denies illicit drugs use.Her mother has diabetes .Her father died of a myocardial infarction at the age of 40 years.Her temp is 37.2(99F),BP 110/70 mmHg, and pulse is 74/min.Lab studies reveal:

Serum NA 140mEq/L
Serum K 2.2mEq/L
Bicarbonate 4.2mEq/L
Blood glucose 90 mg/L
Aldosterone Elevated
Renin activity Elevated

The urine assay for diuretics is negative. Urine chloride conc is 60 mEq/L (normal is =20mEq/L).Which of the following is the most likely diagnosis ?

A. Primary hyperaldosteronism
B. Diuretic abuse
C. Bartter syndorme
D. Surreptitous vomiting
E. Renin-secreting tumor
Yes its C, whichs defective Na & Cl reabsorption at TALH, cause more Na wasting which in turn stimulate renin-angiotensin-aldosterone system . Hyperaldosteronism cause K loss with H retention to keep neutrality but This would cause overwhelming HCO3 retention resulting in alkalosis. Again body should keep its ions in equilibrium , alkalosis caused by negatively charged HCO3 should be associated with loss of the same charge ion (CL) in the urine.
The overall blood tests would be hypo K, CL & hyper HCO3. High Urine K & CL.
This finding would be the same as diuretic overuse, but since the screen was negative, its unlikely to be the cause.
Renin secreting tumor should cause hight Bl.P.
A, would be associated with low renin.
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My Answer also C Barter syndrome..

Renin - Aldosterone combinations.

Conn's Syndrome : Hyporeninemic Hypoaldosteronism.
Liddle Syndrome : Hyporeninemic Hyperaldosteronism.
Barter Syndrome : Hyperrenimic Hyperaldosteronism.
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Thank God you cleared that up... This question was haunting me!!!

Now it makes sense.... Alkalosis, hypoK Bartters
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Quote:
Originally Posted by cingulate.gyrus View Post
My Answer also C Barter syndrome..

Renin - Aldosterone combinations.

Conn's Syndrome : Hyporeninemic Hypoaldosteronism.
Liddle Syndrome : Hyporeninemic Hyperaldosteronism.
Barter Syndrome : Hyperrenimic Hyperaldosteronism.

Just to clarify, Conn's is Hyporeninemic HYPERalsoteronism (that is why is called primary HYPERaldosteronism)
Whereas Liddle syndrome is HYPOreninemic HYPOaldosteronism (its a pseudoaldosteronism state)

This is from eMedicine (I do it like this because im not as cool as Novobiocin and suck at editing and putting quotes )


Liddle syndrome
Liddle syndrome is an autosomal dominant disorder that can partially mimic hyperaldosteronism. Patients present at a young age with hypertension and hypokalemia. Both PRA and aldosterone levels are suppressed. It is caused by mutations of the carboxy terminus of the beta-subunits or gamma-subunits of the renal epithelial sodium channel (ENaC), which result in a constitutively open channel. Treatment with the potassium-sparing diuretic triamterene is often effective.

Last edited by XpaezX; 09-05-2012 at 07:15 AM.
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This Question has subtle differences between the options,which requires clear knowledge and fast thinking.

The differetial diagnosis of normotensive patients with hypovolemia and metabolic alkalosis include :
1. Diuretic Use
2.Surreptitious vomiting
3.Bartter syndrome
4.Gitelman syndrome

Classic Bartter syndrome usually presents early in life as polyuria,polydypsia and growth and mental retardation.However,presentation can occur later in life , as in this patient .
Quote:
Source http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001352/
Bartter syndrome
The condition is caused by a defect in the kidney's ability to reabsorb sodium. Persons with Bartter syndrome lose too much sodium through the urine. This causes a rise in the level of the hormone aldosterone and makes the kidneys remove too much potassium from the body. This is known as potassium wasting.

The condition also results in an abnormal acid balance in the blood called hypokalemic alkalosis, which causes too much calcium and chloride in the urine
Gitelman syndrome is a subset of Bartter syndrome with a defect in the distal convoluted tubule(as opposed to Bartter syndrome in which defect is in loop of henle) causing the same sequence of events.Activated RAAS causes an increase in potassium and hydrogen ion secretion leading to hypokalemia and metabolic alkalosis.

All four conditions listed above have elevated plasma and renin levels,hypokalemia and metabolic alkalosis. Urine chloride level is markedly elevated in bartter and Gitelman syndrome but not in diuretic use or surreptitious vomiting,making Bartter syndrome the diagnosis.

Conclusion-Patient with Bartter syndrome have hypokalemia,urinary cholride level>20 mEg/L(mostly >40 mEq/L), metabolic alkalosis and normal blood pressure.

Choice A and E -Primary hyperaldosteronism and renin secreting tumor are charchterized by hypertension (not seen in this patient) ,metabolic alkalosis and hypokalemia.Moreover Serum Sodium tends to be higher in both these conditions ,which is normal in this normotensive patient.

Choice B. It can be difficult to differentiate diuretic use from bartter syndrome.However,if Diuretic abuse is suspected ,measurement of Urine diuretic level (negative in this patient) can be performed.

Choice D. In patient with serreptitious vomiting , characteristic physical finding(eg scars/calluses on the dorsum of the hands,dental erosions) might be present.These patient also have a low urine chloride concentration due to hypovolemia and hypochloremia.
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Quote:
Originally Posted by step_enhancer View Post
A 20 yr old Caucasian woman comes to the physician because of weakness, fatigue, polyuria and polydipsia.She has had these symptoms for the past 3 months.She has no other medical problems.She has smoked one pack of cigarettes daily for 2 years,drinks alcohol on weekends, and denies illicit drugs use.Her mother has diabetes .Her father died of a myocardial infarction at the age of 40 years.Her temp is 37.2(99F),BP 110/70 mmHg, and pulse is 74/min.Lab studies reveal:

Serum NA 140mEq/L
Serum K 2.2mEq/L
Bicarbonate 4.2mEq/L
Blood glucose 90 mg/L
Aldosterone Elevated
Renin activity Elevated

The urine assay for diuretics is negative. Urine chloride conc is 60 mEq/L (normal is =20mEq/L).Which of the following is the most likely diagnosis ?

A. Primary hyperaldosteronism
B. Diuretic abuse
C. Bartter syndorme
D. Surreptitous vomiting
E. Renin-secreting tumor
C.) bartter syndrome
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