DIT review - GI 2 Flashcards
Diagnostic criteria of IBS
- Recurrent abdominal pain associated with > 2 of the following:
- Pain improves with defecation
- Change in stool frequency
- Change in stool appearance
- Can be associated with diarrhea, constipation, or both
- Not associated with rectal bleeding, nocturnal abd pain, weight loss, elevated inflammatory markers, or electrolyte abnormalities
What is the most common congenital anomaly of the GI tract
Meckel diverticulum
What is the defect in Meckel diverticulum?
Persistance of vitelline duct
2 types of epithelium in Meckel’s?
Gastric, pancreatic
Characteristic presentation of intussusception
Currant jelly stools
Diseases associated with meconium ileus
- Meconium plug obstructs intestine, preventing stool passage at birth
- Seen in Hirschprung disease and Cystic Fibrosis
What is intestinal ileus
- Intestinal hypomotility (lack of peristalsis) without obstruction
- Leads to constipation and decreased flatulence
What is angiodysplasia?
- Tortuous dilation of vessels within the bowel, leading to hematochezia
- Unexplained GI bleeding and anemia
Describe carcinoid tumor and carcinoid syndrome
- Carcinoid tumor:
- Neuroendocrine cells that secrete serotonin
- Most often found in appendix, ileum, rectum, and lung
- Carcinoid syndrome
- Occurs if there is metastasis outside GI tract (otherwise 5HT will be metabolized in the liver)
- Symptoms à BFDR
- Bronchospasm
- Flushing
- Diarrhea
- Right-sided heart disease/murmur
What are the GI problems associated with Down Syndrome
- Duodenal atresia
- Hirschsprung disease
- Celiac disease
- Annular pancreas
Lymph drainage and arterial blood supply above and below pectinate line
- Pectinate line
- Where endoderm meets ectoderm
- Above pectinate line:
- Lymph drainage = internal iliac
- Blood supply = superior rectal artery (branch of IMA)
- Below pectinate line:
- Lymph drainage to superficial inguinal
- Blood supply = inferior rectal artery (branch of internal pudendal)
Most common cancer above and below pectinate line
Above = adenocarcinoma
Below = squamous cell
what is proctitis?
- Inflammation of perianal region and rectum
- Usually due to fecal matter in the area for an extended period of time
Describe the progression from adenoma to carcinoma in colorectal cancer
- Normal colon
- APC gene mutation
- Colon at risk for polyps
- KRAS mutation
- Development of polyps
- p53 mutation + increased expression of COX
- Progression to carcinoma
What is Turcot syndrome
FAP + malignant CNS tumor (medulloblastoma)
What is Lynch Syndrome
- Aka Hereditary Nonpolyposis Colorectal Cancer (HNPCC)
- Autosomal dominant
- Defect in DNA mismatch repair
- Cancer that does NOT arise from polyps
Most common location of diverticulitis
Sigmoid colon (LLQ pain)