[Haisook]

Another question that I've written.

A 55 year old Caucasian man comes into your office. He seems very distressed. He tells you about an incident that happened to him earlier this morning while he was in a meeting at work. He says that all of a sudden he uncontrollably urinated on himself. Moreover, his wife had been telling him for weeks that he had been acting all childish. He says he does not know what's wrong with him and that he feels like he's a little boy. While talking with you he suddenly urinates a large amount of urine on himself . He seems very embarrassed and apologizes repeatedly. The most likely cause for this patient's condition is:

A. Cerebral lesion
B. Lesion in the sacral region of the spinal cord
C. Denervation of the urinary bladder
D. Detrusor muscle inactivity
E. Schizophrenia, disorganized type
F. Acute psychosis

Please attach an explanation to your choice.

 

[drmodi44]

well i was confused with
B. Lesion in the sacral region of the spinal cord
C. Denervation of the urinary bladder
D. Detrusor muscle inactivity

hmm...u said large amount of urine....so there cant be D. Detrusor muscle inactivity or C. Denervation of the urinary bladder.....because in these 2 detruser muscle hypoactivity occurs...with urinary retention n overflow incontinence....which cant be of large amount....

A. Cerebral lesion.....in cerebral lesion inhibitory control is lost so....bladder become hyperactive....The bladder empties too quickly and too often...with relatively low quantities and storing urine in the bladder is difficult.... people with this problem rush to the bathroom and even leak urine before reaching their destination.... They may wake up frequently at night to void.

so m going with B. Lesion in the sacral region of the spinal cord.... sensory neurogenic bladder....pt may not be able to sense when the bladder is full...n through detruser reflex voiding of large amount of urine occurs....

 

[step1an]

E. Schizophrenia, disorganized type

 

[drmodi44]

i overlooked " his wife had been telling him for weeks that he had been acting all childish. He says he does not know what's wrong with him and that he feels like he's a little boy."...

hey Haisook thanks to god that u r not Qs writter in USMLE....
it was a bit tough for me.....

 

[donofitaly]

One thing i have a good feeling is that it is overflow incontinence. And i feel his wife's history about him behaving as a child is pointing towards

E. Schizophrenia, disorganized type.

 

[Pixie]

i would go with cerebral lesion because acting childish+loss of bladder control.possible that he has suffered some sort of small lacunar stroke.

 

[MWM1988]

a) Cerebral lesion ... particularly in the frontal lobe .. because of the childish behavior with affection of the limbic system and presence of the centres of voluntary control of urination at the medial side of the cerebral cortex

I was confused between cerebral lesion and Schizophrenia .. but I think Schizophrenia can't be the answer because the patient is aware of his abnormal behaviors and appologizes after doin' it and this is not a feature of Schizophrenia or any other psychotic disorder

 

[Haisook]

Faith and MWM1988 got it right!

Correct answer is:
A. Cerebral lesion

MWM1988's post summarizes the whole thing, but I'll write down the full explanation.

The patient presents with a very distressing problem which is involuntary uncontrollable voiding of large amounts of urine. This is called uninhibited neurogenic bladder. Only one cause among the listed causes can be responsible for this; cerebral lesion. A lesion in the cerebrum, particularly in the frontal lobe, may affect the corticopontine pathway that's normally responsible for controlling the pontine micturition center. A lesion like this one can produce involuntary voiding that is well-coordinated (because every structure downstream is functioning), hence the large amounts of urine voided (i.e. bladder emptied). The diagnosis is backed up by the childish features the patient's wife had been accusing him, a sign of personality changes that are common in patients with a frontal lobe lesion.

Immaturity of this pathway is seen in children prior to toilet training.

B. Lesion in the sacral region of the spinal cord: lesion in sacral segments (S2, 3, 4) can produce an autonomous bladder. Because such lesion technically denervates the bladder, there will be flaccid paralysis, with urging, and dribbling of urine (overflow incontinence). Coordinated voiding is not possible.

C. Denervation of the urinary bladder: this defines both a motor and a sensory neurogenic bladder. Voiding is not possible, and the patient is not aware of bladder fullness (no urge). Overflow incontinence may occur, and even rupture of the bladder is possible.

D. Detrusor muscle inactivity: when this muscle contracts, it empties the bladder. Inactivity of this muscle denotes urine retension, not voiding.

Moreover, choices B, C, D do not explain the childishness the patient had been accused of by his wife.

E. Schizophrenia, disorganized type: the patient does not show any signs of schizophrenia. Urination on one's self is common in the disorganized type of schizophrenia, but such patient would be indifferent to his behavior. The patient presented here seems distressed about it, and he shows signs of embarrassment and apologizes repeatedly after the incident.

F. Acute psychosis: the patient does not show any signs of mania. In mania, the patient is egosyntonic (he likes his behaviors), while this patient is clearly egodystonic (he dislikes his behaviors).

 

[step1an]

thanks for sharing this question & nice explanation...

Can u plz mention the source of this question

 

[Haisook]

thanks for sharing this question & nice explanation...

Can u plz mention the source of this question

I've written this question and explanation myself, but I was inspired by question no. 34 in Pathology & Pathophysiology Test 4 in Kaplan Qbook.

 

[drmodi44]

doesn't hyperactive bladder empty too quickly n too often with less amount of urine...??:notsure:

 

[Haisook]

doesn't hyperactive bladder empty too quickly n too often with less amount of urine...??:notsure:

If you mean by hyperactive bladder an uninhibited neurogenic bladder, then no, the bladder will void only when it's full. When the bladder is not full, the internal urethral sphincter is closed and it stops the bladder from emptying. When it's full, the internal sphincter opens. The corticopontine pathway acts as the "Stop! Not now!" order to voiding when the bladder is full & the internal sphincter is open. This order is removed in this condition. It's the same case with toddlers; they'll void once in a while to empty the bladder completely.

May be a hyperactive bladder is a term for another condition? :notsure:

 

[drmodi44]

hmm...overactive bladder occurs in spinal cord injury...

http://www.medicinenet.com/overactive_bladder/article.htm

 

[dazzles]

Awesome question. Please keep writing these. You're good at it. After your exam, you may want to write some questions for a question bank that hires students to make some cash on the side.