Module 9 - Gastrointestinal Disorders Flashcards
-1- results from an absence of ganglion cells in the mucosal and muscular layers of the colon. Ganglion cell absence results in failure of the colonic muscles to relax in front of an advancing bolus. In 80% of individuals, aganglionosis is restricted to the rectosigmoid colon (short-segment disease); in 15%–20%, aganglionosis extends proximal to the sigmoid colon (long-segment disease); in about 5%, aganglionosis affects the entire large intestine (total colonic aganglionosis).
Aganglionic segments have normal or slightly narrowed caliber with dilation of the normal colon proximal to the obstructing aganglionic segment.
A familial pattern has been described, particularly in total colonic aganglionosis. The incidence of -1- is 1 in 5000 live births; it is four times more common in boys than girls.
Mutations in the ret proto-oncogene have been identified in about 15% of nonsyndromic cases. The most common chromosomal abnormality associated with -1- is -2-; 2%–10% of all individuals with -2- may have -1-.
CONGENITAL AGANGLIONIC MEGACOLON (HIRSCHSPRUNG DISEASE)
- Hirschsprung disease
- Down syndrome
Failure of the newborn to pass meconium, followed by vomiting, abdominal distention, and reluctance to feed suggest the diagnosis of -1-.
- Hirschsprung disease
On rectal suction biopsy samples, ganglion cells are absent in both the submucosal and muscular layers of involved bowel.
CONGENITAL AGANGLIONIC MEGACOLON (HIRSCHSPRUNG DISEASE)
Plain abdominal radiographs may reveal dilated proximal colon and absence of gas in the pelvic colon. Barium enema using a catheter without a balloon and with the tip inserted barely beyond the anal sphincter usually demonstrates a narrow distal segment with a sharp transition to the proximal dilated (normal) colon.
CONGENITAL AGANGLIONIC MEGACOLON (HIRSCHSPRUNG DISEASE)
Rectal manometric testing reveals failure of rectoanal inhibitory reflex (RAIR), relaxation of the internal anal sphincter after distention of the rectum in all patients with …, regardless of the length of the aganglionic segment.
Hirschsprung disease
-1- accounts for 15%–20% of cases of neonatal intestinal obstruction. It must be differentiated from the -2- syndrome by -3-.
- Hirschsprung disease
- small left colon
- biopsy
Treatment for Hirschsprung disease is surgical. Depending on the child’s size and state of health, a -3- may be performed or the surgeon may undertake a primary repair.
Complications after -3- or primary repair include fecal -5-, fecal -6-, anastomotic breakdown, or anastomotic stricture. -8- occurs postoperatively in 15% of patients. Recent studies have shown that patients even after -3- or primary repair have an altered -9-; the role this may play in -8- or other long-term issues for children is still under investigation.
- diverting colostomy (or ileostomy)
- retention
- incontinence
- Enterocolitis
- microbiome
Chronic constipation in childhood is defined as two or more of the following characteristics for -3-: (1) -4- bowel movements per week; (2) more than one episode of -5- per week; (3) impaction of the rectum with stool; (4) passage of stool which -7- ; (5) retentive posturing and fecal -9-; and (6) pain with defecation.
- 2 months
- fewer than three
- encopresis
- obstructs the toilet
- withholding
Infants younger than 3 months often -1-, and -2- the face while passing normal stools. Failure to appreciate this -3- may lead to the -4- use of laxatives or rectal stimulation.
- grunt, strain
- turn red in
- normal developmental pattern
- unwise
Causes of Constipation:
Dietary causes (Undernutrition/dehydration; -3-; Lack of bulk)
Drugs (-6-, antihistamines, vincristine)
GI Structural defects (anal fissure, tumor of small bowel/colon, -12-)
Smooth Muscle Diseases [dermatomyositis, SLE, chronic intestinal pseudo-obstruction (CIPO)]
Myenteric ganglion abnormalities (Hirschprung, Waardenburg, multiple endocrine neoplasia 2a)
Hypo-/hyperganglionosis (Multiple -22-; Intestinal neuronal dysplasia; Chronic intestinal pseudo-obstruction)
-25-
Metabolic/endocrine disorders [Hyperparathyroidism; Renal tubular acidosis; Vitamin D intoxication (hypercalcemia); Idiopathic hypercalcemia]
Skeletal muscle weakness or incoordination (CP, MD, myotonia)
- Excessive milk intake
- narcotics
- chronic volvulus
- endocrine neoplasia 2b
- Spinal cord defects
Onset: 1. 2–3 y 2. At birth
Abdominal distention: 1. Rare 2. Present
Nutrition and growth: 1. Normal 2. Poor
Soiling and retentive behavior: 1. Intermittent or constant 2. Rare
Rectal examination: 1. Ampulla full 2. Ampulla may be empty
Rectal biopsy: 1. Ganglion cells present 2. Ganglion cells absent
Rectal manometry: 1. Normal rectoanal reflex 2. Nonrelaxation of internal anal sphincter after rectal distention
Barium enema: 1. Distended rectum 2. Narrow distal segment with proximal megacolon
- Retentive Constipation
2. Hirschsprung Disease
In children with poor diets, increased intake of -1-, and -2- may be sufficient therapy in mild constipation.
-3- should not be given to nonambulatory infants, physically handicapped or bed-bound children, or any child with GE reflux. Aspiration of -3- may cause -4-. Recurrence of -5- is common and should be treated promptly with a short course of stimulant laxatives or an enema.
- high-residue foods (such as bran, whole wheat, fruits and vegetables)
- water
- Mineral oil
- lipid pneumonia
- encopresis
-1- is a slit-like tear in the squamous epithelium of the -2-, which usually occurs secondary to the passage of large, hard fecal masses, typically at the superior and inferior aspects of the -2-.
The infant or child with -1- typically cries with defecation and will try to hold back stools. Sparse, bright red bleeding is seen on the outside of the stool or on the toilet tissue following defecation.
When a(n) -1- cannot be identified, it is essential to rule out other causes of rectal bleeding such as -3-, perianal inflammation due to -4-, or -5- Rarely, silver nitrate cauterization or surgery is indicated. Surgery of the -2- should be avoided in patients with Crohn disease because of the high risk of recurrence and progression after surgery.
- Anal fissure
- anus
- juvenile polyp
- GAβHS
- inflammatory bowel disease (IBD).
… is a common anomaly of infant girls. Its usual presentation in infants is constipation and straining with stool with the introduction of solids.
Anterior anal displacement (Anterior displacement of the anus)
-1- -2- usually presents in the newborn period. The -1-aperture may be very small and filled with a dot of meconium.
- Anal
2. stenosis
-1- -3- typically develops during the fifth to seventh week of pregnancy and occurs in 1 of 5000 live births, slightly more common males.
Defects are generally classified as -2- where the rectum may not connect to the -3-, a membrane may be present over the -3- opening, or the -3- opening may be narrow or misplaced.
In -4- -1- -3-, physical examination usually shows no -3- musculature. There may be a rectoperineal, rectovesicular, rectourethral, or rectovaginal fistula; hypoplastic buttocks; cloacal anomalies; and sometimes evidence of distal neurologic deficit.
- Imperforate
- low (rectoperineal malformation)
- anus/anal
- high
… in children leads to a spectrum of clinical disease, from asymptomatic colonization to severe pseudomembranous colitis with fever, severe abdominal pain, and bloody diarrhea.
Risk factors for … disease include previous antibiotic use and a variety of chronic diseases, including immunodeficiency, cystic fibrosis, Hirschsprung disease, IBD, oncology patients, and solid-organ transplant recipients.
Community-acquired … disease in healthy hosts is increasing in incidence.
C difficile
… is a spore-forming gram-positive bacillus that causes human disease via the secretion of enterotoxins that cause necrotizing inflammation of the colon.
C difficile
