constipation

Question 1

what is constipation defined as ?

Answer 1

either difficulty passing stool
or passing stool too infrequently ( for a period of 4 days or more )

Question 2

what are the two types of constipation according to cause ?

Answer 2

primary : functional
secondary : organic

Question 3

what are the different causes of functional constipation ?

Answer 3

normal transient
slow transient
pelvic floor dysfunction

Question 4

what facilitates the removal of water from faeces ?

Answer 4

CFTR channel

Question 5

what is the cause of normal transient constipation ?

Answer 5

decreased water and fiber content

Question 6

what is the clinical application of the CFTR gene ?

Answer 6

CF patients - have dry stools and lead to constipation
cholera toxin - stimulates CFTR and causes diarrhea
lubi or amiprostone - a CFTR analogue causing diarrhea

Question 7

what is the criteria for the diagnosis of constipation ?

Answer 7

according to the Rome IV criteria :
at least 2 symptoms of the following 6 , for the past 6 months :
1- fewer than 3 spontaneous bowel movements per week
2- straining for more than 25% of defecation attempts
3- lumpy or hard stools
4- sensation of anorectal obstruction or blockage
5- sensation of incomplete defecation
6- manual manoeuvers required

Question 8

what are the two characteristic movements associated with colonic movement ?

Answer 8

1- repetitive non propulsive contractions
2- high amplitude propagated contractions HAPC which usually happen iin the morning

Question 9

which colonic movement is decreased during constipation ?

Answer 9

HAPC

Question 10

what is the major movement neurotransmitter ?

Answer 10

serotonin
5HT3 and 5HT4

Question 11

what is the clinical application of 5HT in colonic motility ?

Answer 11

carcinoid syndrome , where theerre is too much seretonin and hence the diarrhea

Question 12

what drugs are associated with 5HT ?

Answer 12

5HT4 agonist - prucalopride
5HT3 agonist - ondansetron ( antiemetic)

Question 13

what is the anatomy associated with the pelvic floor ?

Answer 13

1- internal anal sphincter - not under conscious control
2- external anal sphincter
3- puborectalis ( relaxes with defecation)

Question 14

what is the rectoanal inhibitory reflex ?

Answer 14

RAIR - rectal distention by stool or gas induces relaxation of the internal anal sphincter

Question 15

what is the clinical application of RAIR ?

Answer 15

hirschsprung disease , a congenital disorder where the internal anal sphincter fails to relax in response to distention by stool or gas

Question 16

in the diagnosis of the cause of constipation what is the algorithm ?

Answer 16

history and examination
baseline labs
therapeutic trial of fiber/laxatives
inadequate response then anorectal manometry

Question 17

what are the the results that can be concluded from anorectal manometry ?

Answer 17

1- if normal , determine the colonic transit
2- if inconclusive - perform barium or MR enema
3- if abnormal - defecatory disorder

Question 18

what are the alarming symptoms associated with constipation ?

Answer 18

unexplained weight loss
unexplained anemia
acute constipation in elderly
inability to pass flatus
hematochezia

Question 19

what must be done during examination for a patient complaining of constipation ?

Answer 19

digital examination during valsalva maneuver

Question 20

what lab investigations should you ask for for a constipated patient ?

Answer 20

CBC
TFT
electrolyte panel

Question 21

what is the most useful imaging modality in acute setting of constipation ?

Answer 21

plain abdominal xray

Question 22

when do we move on to physiologic testing ?

Answer 22

if there is no response to laxatives or fiber trial

Question 23

what is anismus ?

Answer 23

dyssynergic defecation , inadequate widening of the anorectal angle

Question 24

what is the first linee mnmnt for norrmal or slow transit constipation ?

Answer 24

laxatives

Question 25

what is the first line management for defecatory disorder ?

Answer 25

pelvic floor training , dietitian and psychology
if no improvement - repeated balloon expulsion

Question 26

what does a defecatory disorder actually mean ?

Answer 26

failure of normal relaxatioion of the puborectalis and the xternal anal sphincter

Question 27

which individuals are more commonly to have slow transit constipation ?

Answer 27

young women who have infrequent bowel movements
may be associated with failure of meal stimulated colonic motility