GI tract #1: Witwer Flashcards
1
Q
Air sacs in lungs, and vessels= ______ epithelium
A
simple squamous fx: allows materials to pass through by diffusion, and secretes lubricating substance
2
Q
Kidney tubules= made of ______ epithelium
A
simple cuboidal fx: secretes/absorbs
“simple cube in the kidney tube”
3
Q
Bronchi, uterus, GIT= ______ epithelium
A
simple columnar (these ciliated tissues are in bronchi, uterine tubes, and uterus smooth muscle(nonciliated) fx: absorbs, it also secretes **mucous/enzymes****
4
Q
Trachea, upper resp. tract= _____ epithelium
A
Pseudostratified columnar epith. (=ciliated tissues) fx: Secretes mucous, ciliated tissue moves mucous
5
Q
Stratified Squamous epithelium lines the:
A
Esophagus, mouth and vagina –protects against abrasion
6
Q
Stratified Cuboidal epithelium lines the:
A
sweat, salivary, and mammary glands –protective tissue
7
Q
Stratified columnar epithelium lines the:
A
male urethra –secretes and protects
8
Q
Transitional epithelium lines the:
A
genitourinary tract (GUT) (aka bladder, urethra and ureters) –allows the urinary organs to expand and stretch
9
Q
Gastrointestinal wall has 4 layers (list)
A
-Mucosa – inner layer -Submucosa -Muscular Layer -Serosa/Adventitia
10
Q
Describe the Mucosa (of the GI wall)
A
(inner layer) -Epithelium with glandular elements (goblet cells secreting mucus – lubricates) –highly specialized depending on role, esophagus, stomach (secretion), small bowel (absorption) and large bowel. -Lamina propria is under the epithelium and contains blood vessels, nerves, immune cells -Muscularis mucosae – aids peristalsis
11
Q
Describe the Submucosa of the GI wall
A
contains nerves, blood vessels, and elastic and collagen fibers that supports mucosa
12
Q
Describe the muscular layer of the GI wall
A
contains both longitudinal and circular smooth muscle – peristalsis.
13
Q
Describe the Serosa/Adventitia (of the GI wall)
A
loose CT on outside of the bowel wall
14
Q
What holds the GI wall (4 layers) in place?
A
*Mesentery holds all of this in place.
15
Q
Key components of Generic Bowel:
A
Mucosa – epithelium protects and lines bowel, secretes mucus , lamina propria supports and nourishes epithelium Submucosa – Supports mucosa, contains glands **Muscularis – muscles of peristalsis **Serosa/Adventitia – serosa secretes fluid to decrease friction of bowel on bowel, adventitia is supporting connective tissue.
16
Q
Meissner’ Plexus=
A
aka Submucosal plexus =PNS secretomotor innervation to mucosa **located in Submucosa within bowel wall
(extrinsic!!)
17
Q
Auerbach’s Plexus=
A
-aka Mysenteric plexus =PSN and SNS peristalsis motor innervation **located in Muscularis Propria within bowel wall
(**intrinsic)
18
Q
Mucosa consists of 3 things:
A
(inner layer) -epithelium -Lamina propria -Muscularis mucosae
19
Q
Glands contained within the submucosa:
A
-glands in mucosa -ducts of glands located outside of tract
20
Q
Muscularis= _____ muscle and ____ muscle
A
circular muscle and longitudinal muscle
21
Q
Serosa=
A
areolar CT and epithelium
22
Q
Mesentary goes around the ______
A
peritoneum (comprised of mesenteric folds (includes veins and nerves )
23
Q
Myenteric Plexus isPart of the _____ Enteric Nervous System -provides BOTH sympathetic and ______
A
Intrinsic -Meissner plexus= secretomotor -Myenteric plexus (Auerbach) provides both sympathetic and parasympathetic input to the muscular layers of the muscularis – circular and longitudinal muscles of peristalsis -lots located in the large bowel and distal large bowel (areas of peristalsis) (If you cut the vagus nerve, you will still get bowel function and peristalsis due to the intrinsic nervous system. KNOW )
24
Q
The area of the GIT is about the size of a _____
A
football field!
25
Mucous membranes line:
gut, lungs, nose, genitalia, urinary tract, eyes, middle ear
26
Mucous is composed of:
-\*Mucin: Glycoproteins, a central core of protein with thousands of sugar molecules branching off added with water making gel. -Also contains antiseptic enzymes and immunoglobulins
27
Average human nose produces ____ liters of mucous per day
1 Liter
28
Phlegm= _______ mucous
respiratory mucous -Green or yellow mucus 2/2 viral or bacterial infection. --\*Increased production found in infections, allergies, asthma, increased histamines (movement of mucus via the cilia to the pharynx)
29
Why don’t the bacteria in the GIT overwhelm the body??
\*\*There are Immune Barriers assisted by a dense mucus layer.
30
Describe the Immune barriers that are assisted by a dense mucus layer
1. There are two layers of mucus on the GIT wall. 2. A thin outer mucus layer that microbes can thrive in. 3. A dense inner mucus layer (yellow in picture below) on top of epithelium that has lots of antimicrobial peptides (AMP secreted by Paneth Cells) and immunoglobulins IgA. 4. And there is an immune cell layer in the intestinal epithelial cells. 5. Reticuloendothelial immune cells in the liver. SFB=segmented filamentous bacteria (Mucous is SO important in the GI tract -problem with cholera– mucous is eliminated, these Pts die primarily from dehydration and vulnerable to superimposed infections that break through mucosa)
31
In the future: Inflammatory Bowel Disease, ie Ulcerative Colitis and Crohn’s Disease may be secondary to a \_\_\_\_\_, and imbalance between the patient’s diet, immune system and the intestinal microbiome.
dysbiosis= imbalance b/w Pt’s diet, immune system, and intestinal microbiome
32
\*\*GI fluid volumes: -Ingest ____ mL/day H20 -saliva= \_\_\_\_mL/day
KNOW FOR EXAM!! -2000 mL/day H20 -1500 mL/day
33
Bile: \_\_\_\_mL/day Gastric secretions: \_\_\_\_\_mL/day
-500 - 2000
34
Pancreatic juices: ____ ml/day produced
1500
35
Small intestine absorbs ____ mL/day
8500 mL/day
36
Intestinal secretions: ____ mL/day
1500
37
Colon absorbs: ____ mL/day
400
38
\_\_\_\_mL of H20 excreted per day
100 mL/day
39
Pain in Right upper Quadrant ddx:
-R/O gall bladder dz (cholecystitis) -Choledocolithiasis (= gallstones) -\*\*\*\*Glisson's capsule!!= stretching of it= intense pain! -Hepatitis -Pyelonephritis -herpes Zoster -PNA -empyema -Duodenitis
40
Right lower Quadrant pain ddx:
\*\*appendicitis -ectopic pregnancy -Ovarian cyst -salpingitis -endometriosis -Diverticulitis -Pyelonephritis -hernia perforated ulcer
41
Epigastric region pain ddx:
(epigastric region=midline) -peptic ulcer -Gastritis -\*\*pancreatitis -duodenitis -gastroenteritis -MI
42
Left upper quadrant pain ddx
-gastritis -pancreatitis -Splenic enlargement/rupture -Infarction -Pyelonephritis -Nephrolithiasis -Herpes zoster -MI PNA -IBD
43
Left lower Quadrant pain ddx
-diverticulitis -intestinal obstruction -IBD -appendicitis -Salpingitis
44
Pt presents with lower mid abdomen pain, do you have to worry about ectopic pregnancy?
YES!!! KNOW for exam
45
Key components of Generic bowel (again, list 4)
Mucosa – epithelium protects and lines bowel, secretes, lamina propria supports and nourishes epithelium Submucosa – Supports mucosa, contains glands Muscularis – muscles of peristalsis Serosa/Adventitia – serosa secretes fluid to decrease friction of bowel on bowel, adventitia is supporting connective Tissue.
46
Upper esophageal Sphincter: -Skeletal muscle? -Primary muscle=? KNOW
Upper Esophageal Sphincter: -Skeletal Muscle--\> no conscious control -Primary muscle is Cricopharygeus muscle\*\*\*
47
\*\*Cricopharyngeus muscle is part of the inferior _______ muscle
Pharyngeal Constrictor muscle
48
Note _______ of the inferior pharyngeal sphincter/cricopharyngeus
\*complexity Remember: the esophagus when it passes the heart, it’s right up against the Right atrium. So an enlarged heart, can cause dysphagia!!!
49
Esophageal anatomy
add pic -Esophagus Enters abdominal cavity through esophageal hiatus !!! Along the esophagus is the vagus nerve!! Vagus innervates esophagus for motility/secretions AND it goes into the stomach and creates set up for peristalsis and secretions
50
Swallowing/Degultion: is coordinated by ______ -initiated by?
-Swallowing/Deglutition Center in medulla and pons - Bulb -Initiated by touch receptors in Pharynx
51
4 phases of swallowing (list 4)
-oral preparatory phase -Oral Phase (buccal) -Pharyngeal phase -Esophageal phase (OOPE)
52
Describe the Oral Preparatory Phase: -which nerves are involved?
food processed by Mastication (V3) and Salivation (VII) into bolus
53
Oral Phase (Buccal)= -nerves involved?
bolus moved to back of tongue, anterior tongue lifts to hard palate and retracts posteriorly to force bolus into oropharynx. Posterior tongue lifted by Mylohyoid m, elevating soft palate and sealing the nasopharynx (V, VII, XII)
54
Pharyngeal phase= -nerves involved?
Bolus advanced from pharynx to esophagus. Soft Palate is elevated to Posterior Nasopharyngeal wall by Levator veli palatini. Superior Constrictors bring Palatopharyngeal folds together. Larynx and Hyoid are elevated and pulled forward to the Epiglottis to relax Cricopharyngeus m. (V, X, XI, XII)
55
Swallowing: -Trigeminal nerve (CN V) involvement?
important in Chewing and sensation (pain, temperature, touch) to the mouth and anterior 2/3 of tongue. PSNS to Salivary Glands in Mouth and Parotid Gland.
56
Swallowing: -Facial Nerve (CN VII) involvement?
taste on anterior 2/3 of tongue via Chorda Tympani
57
Swallowing: -Glossopharyngeal Nerve (CN IX) involvement?
taste and sensation on posterior 1/3 of Tongue, sensation in oropharynx and upper pharynx
58
Swallowing: -Vagus Nerve (CN X) involvement?
-sensation from mucous membranes of pharynx, larynx, esophagus, and abdominal viscera of foregut and midgut -taste from epiglottis -motor of soft palate, pharynx and larynx and smooth muscle of abdominal viscera. -Important for airway protection.
59
Swallowing: -Spinal Accessory Nerve (CN XI) involvement?
Assists in the swallowing function
60
Swallowing: -Hypoglossal nerve (CN XII) involvement?
motor nerves to the Tongue
61
Schema of Swallowing Function: -A -B? -C-?
A: Soft palate in neutral position, laryngeal inlet and laryngeal cavity open B: Back of tongue elevated, palate depressed. Oropharyngeal isthmus closed C: opening b/w nasal and oral parts of pharynx closed by soft palate. Oropharyngeal isthmus open. Epiglottis closed over laryngeal inlet. Larynx & hyoid pulled up and forward resulting in opening of the esophagus
62
Tensor Veli Palatini M. is innervated by?
CN 5--\> muscle when you chew that masticates!! Your food (=muscle of mastication) -Tensor vali pallatini– opens up opening (tube that goes from pharynx to middle ear)
63
Levator Veli Palatini is innervated by?
10th CN,
64
S/Sx of Esophageal disease (list 3)
-heartburn -Dysphagia -dysphagia for SOLID food
65
Heartburn=
Most commonly 2/2 Gastroesophageal Reflux Disease = GERD
66
Dysphagia= dysphagia for solids=
-Difficulty swallowing -Dysphagia for solids--\> THINK obstructive lesion (this is a sx of an obstructive lesion\*\* ON EXAM --Esophageal cancer, esophageal web, stricture, Zenker’s diverticulum
67
Dysphagia for solids and liquids= symptom of a _______ disorder
motility -Oropharyngeal (upper esophageal) dysphagia OR -Lower esophageal dysphagia
68
Describe Oropharyngeal (upper esophageal) dysphagia
-Striated muscles dysmotility -Dermatomyositis, Myasthenia gravis, stroke(causing bulbar signs\*\*)
69
Bulbar Paralysis=
Bulbar paralysis= autoimmune disorder of the muscles Bulbar paralysis= impaired fx of lower cranial nerves (9, 10, 11 ,12). CN 9 (glossopharyngeal) is involved in salivation, swallowing, and the gag reflex. If CN 9 is injured this can lead to dysphagia and reduced gag reflex. Sx: atrophic tongue
70
Describe Lower Esophageal Dysphagia
=Smooth muscle dysmotility -Systemic sclerosis, achalasia, CREST Syndrome (calcinosis/centromere antibodies, Raynaud phenomenon, esophageal dysmotility, sclerodactyly(thickening of the skin), telangiectasia)
71
What is the MC congenital anomaly of the esophagus?(on exam)
\*\*Tracheoesophageal Fistula -A2 most common form
72
Child with Tracheoseophageal Fistula: Sx -dx?
Sx: the child will aspirate into the trachea (and get PNA) or spit up food -Sx: -Air in stomach from TE fistula -Difficulty with feeding -Aspiration pneumonia in newborn -Can be part of other congenital anomalies -Diagnosis: get a 5 inch catheter and if it doesn’t go all the way into the stomach YOU know the child has an obstruction and TE fistula is MC
73
Maternal Polyhydramnios=
\*\*swallowed amniotic fluid not reabsorbed in fetal small bowel (MC source of amniotic fluid in baby is infants urine and baby is constantly swallowing that fluid. BUT if there is an obstruction of that fluid--\> MOM will have polyhydramnios= lots of excess fluid -you may know prior to birth that there is an issue with the babies esophagus if the mom has Maternal Polyhydramnios )
74
Zenker’s Diverticulum= -KNOW!!!
-Pulsion diverticulum through area of weakness (Killian’s Dehiscense) in the Cricopharygeus muscle. Dysphagia, halitosis, regurgitation of food, can become inflamed
75
Normal Gastroesophageal Junction:
-Review slide 30 -Note: Phrenoesophageal Ligament -A fascial ligament allowing independent movement of Diaphragm and esophagus and stomach -Gastoesophageal junction (right by Z line) -note there’s high levels of acid (that may go back up the esophagus--\> and irritate it) --\> you can get break down and metaplasia in the esophagus (pre cancerous ligaments) If the supporting ligaments are lax--\>you will get a hiatal hernia -Fundus of stomach- you have circular and longitudinal muscles
76
Hiatus Hernia: -found in \_\_\_\_% of persons over 50 -Associated with?
50% -Likelihood increases with age -Associated with: --Sigmoid diverticulosis 25% --Esophagitis 25% --Duodenal Ulcers 20 % --Gallstones 18%
77
Sliding Hiatus Hernia: -how common? -clinical Sx?
-MC 99% -clinical Sx: -Heartburn -Nocturnal epigastric distress from acid reflux -Hematemesis -Ulceration and stricture
78
Sliding Hiatus Hernia: -tx?
-Reduce intake of foods that decrease lower esophageal tone – coffee, chocolate, CCB's (Ca 2+ channel blockers) -Avoid large amounts of food -Elevate head of bed -H2 antagonists -Proton pump inhibitors -Prokinetic agent – enhances gastrointestinal motility
79
Hiatus Hernia: -Describe Schatzki Ring -A ring location? -B ring location?
--Common: 10% of patients -Narrowing of lower esophagus caused by a ring of mucosal tissue -\*\*A Ring=above esophagogastric junction -B Ring= at esophagogastric junction -Can cause dysphagia
80
How common are para-esophageal hernias? -associated with high or low mortality?
-\*\*Unusual, about 1% of hernias -Can be fixed and NOT reduced -\*\*associated with HIGH mortality, Abx dont work well
81
GERD: -approx. \_\_\_% of adults have GERD daily -Approx. \_\_\_\_% of pregnant women have GERD -\_\_\_\_\_ _____ present in approx. 70% with GERD
-Approx 10% of adults have GERD daily -Approx 80% of pregnant women have GERD -\*\*Hiatal Hernia present in approx 70% with GERD
82
GERd: risk factors?
Smoking, alcohol, caffeine, fatty foods, chocolate, pregnancy, obesity, and hiatal hernia
83
GERD: -pathogenesis?
-Transient relaxation of the lower esophageal sphincter LES -Reflux of acid and bile into the distal esophagus -Ineffective esophageal clearance of reflux material -Relaxation of the Upper Esophageal Sphincter allows food and acid to enter pharynx and mouth with occasional aspiration into trachea.
84
GERD: clinical sx?
-Non-cardiac Chest Pain -Heartburn, indigestion -Nocturnal cough, nocturnal asthma -Acid injury to enamel -Early satiety, abdominal fullness -Bloating and belching -\*\*Barrett Esophagus
85
GERD: -Diagnosis? -Treatment?
dx: -Esophageal pH monitoring for 24 hours -\*\*Esophageal endoscopy (helps you determine whether the Pt has Barrett Esophagus=pre cancerous condition!!) -Manometry LES pressure \< 10 mmHg -Endoscopy Tx: -see hiatal hernia -Fundoplication
86
GERD: -Esophageal spasm can mimi \_\_\_\_\_\_\_
=can mimic myocardial infarction
87
Reflux Esophagitis: -Barrett Esophagus=
Metaplasia of normal stratified squamous epithelium of lower esophagus into glandular simple columnar epithelium (found in lower GIT) from acid injury (Stratified squamous epithelium--\> changing to Glandular simple columnar epithelium (adenocarcinoma of glandular simple columnar)\*\*\*
88
Barrett's esophagus has a strong association with:
-Ulceration with stricture -Increased risk for adenocarcinoma of esophagus
89
Infectious Esophagitis= is usually a complication of \_\_\_\_
AIDS or in immunocompromised patients
90
Infectious Espohagitis: -MC pathogens? -Presenting Sx?
-Herpes simplex virus (HSV) Cytomegalovirus (CMV) Candida – common in AIDS, can be presenting sign (ex's: candida esophagitis, corrosive esophagitis, eosinophilic esophagitis) -\*\*Presents with odynophagia (painful swallowing)
91
Eosinophilic Esophagitis: -thought to be an _______ \_\_\_\_\_\_ to an allergen
inflammatory response -“Feline esophagus”
92
Corrosive Esophagitis: -Occurs 2/2:
-Secondary to ingestion of a corrosive material, strong alkali (lye) or acid -findings: Stricture formation, perforation
93
Esophageal Varices: -dilated _______ \_\_\_\_ ____ veins?
-Dilated submucosal left gastric veins 2/2 Portal HTN from cirrhosis -Rupture with massive hematemesis -\*\*MC cause of death in cirrhosis (Common cause of death 2/2 to chronic alcoholism= rupture of esophageal varices and bleeding to death)
94
Portal HTN=
-main vein going into the liver, hepatic portal vein is draining the spleen, the stomach, duodenum, terminal ilium and colon and down to the rectum. PORTAL vein brings all that blood flow into the liver soooo the liver can store glucose and fat etc and detox. (portahepatis= has triad of structures: common bile duct, hepatic artery proper, and portal vein) -IF the liver has cirrhosis (Extensive scarring) 2/2 alcohol, hep C, Cirrhosis of the liver with hep C has HIGH incidence of hepatocellular carcinoma!!! -instead of GI tract being trained by portal vein of the liver, it will instead drain into the wrong veins (esophageal veins) that can rupture
95
Diagnosis of Esophageal Varices:
-endoscopy
96
Esophageal Varices: -intrahepatic causes?
cirrhosis of the liver--\> schistosomiasis=disease caused by parasitic flatworm, or from portal vein thrombosis (causes fluid back up that goes into the spleen -blood flow is centrifugal
97
CT scan findings for esophageal varices?
massive!!! Look at the cat scan, shows massive retroperitoneal varicosities
98
Mallory Weiss Tear (KNOW FOR EXAM)
-Severe tear of the distal esophagus/proximal stomach secondary to retching. -Most often associated with alcoholism or bulimia -Pain and hematemesis (tear of the mucosa and parts of the muscularis, commonly seen w/ alcoholism and bulimia)
99
Boerhaave’s Syndrome=rupture of the \_\_\_\_
Distal Esophagus secondary to retching
100
Boerhaave’s Syndrome: -causes of the esophageal rupture?
-Endoscopy 50+% - technically a complication -Retching – Boerhaave’s -Barretts, ulcers, malignancy
101
Boerhaave’s Syndrome: -complications?
-Pneumomediastinum: \*\*Hamman Sign – crunching sound (crepitus) on auscultation -Pleural effusion contains acid, food, amylase -Mediastinitis -
102
Boerhaave Syndrome: -Sx? -untreated mortality %? -treated mortality %?
Odynophagia \*\*Hamman’s sign Tachypnea Dyspnea Cyanosis Fever Shock -\*\*Mackler's triad -\*\*Untreated mortality 100% -Treated: 25% fatal
103
What is Mackler's triad
KNOW!! seen with Boerhaave syndrome -Vomiting -Chest pain -Subcutaneous Emphysema
104
Achalasia: pathogenesis
-Normal relaxation of the smooth muscle in the lower esophageal sphincter (LES) during swallowing is due to nitric oxide and vasoactive intestinal peptide (VIP) -\*\*In Achalasia, there is incomplete relaxation of the LES, a loss of myenteric nerve fibers and inhibitory neurons in myenteric plexus- -Possibly autoimmune -Dilation of esophagus proximal to LES and peristalsis is absent -\*\*Chaga’s Disease is an acquired form, there is destruction of the ganglion cells by amastigotes (parasite)
105
Chaga's Disease (American Trypanosomasis): -etiology (MC organism)? -Acute? -Chronic?
-Trypanosoma cruzi parasite infection resulting from the bite of a Triatomine (reduviid) bug -Acute: Fever and swelling around bug bite -Chronic: Cardiac rhythm abnormalities Myocarditis Dilated esophagus
106
Achalasia: clinical Sx
-Nocturnal regurgitation of food -Dysphagia for solids and liquids -Chest pain and heart burn -Hiccups -\*\*Nocturnal cough from aspiration -Difficulty belching
107
Achalasia: -Sx on X ray?
"bird's beak" appearance -MC due to the autoimmune disease OR with chaga's disease
108
What is the MC primary cancer of the esophagus? -what is the MC precursor?
\*\*adenocarcinoma -Distal esophagus most commonly -Barrett esophagus MC precursor
109
What is the MC cancer of the esophagus in the middle 1/3 of the esophagus?
\*\*Squamous cell carcinoma -Middle third of esophagus Smoking Alcohol Achalasia Plummer Vinson
110
Cancer of the esophagus: (adenocarcinoma, squamous cell carcinoma) -Sx?
-Dysphagia/Odynophagia -Weight loss -Painless supraclavicular nodes -Dry cough and hemoptysis if tracheal invasion -\*\*Hoarseness – recurrent laryngeal nerve
111
Digestion: -Glycocalyx?
=Glycoprotein-polysaccharide covering epithelial cells that aid digestion
112
Carbohydrate and protein digestive products go to the \_\_\_\_
liver via the portal vein
113
Fats go to the lymphatic system via the \_\_\_\_\_\_\_\_
thoracic duct and end up in the venous system
114
Flow of chemicals into stomach controlled by \_\_\_\_
autonomic nervous system and hormones.
115
Where is Gastrin produced? -Gastrin increases ____ secretion
from G cells in stomach secondary to antral distension --\> increases HCl secretion from Parietal cells \*\*KNOW for exam: gastrin is produced by G cells of the stomach. Secondary to ANTRAL distension!!!! This increases HCL secretion from parietal cells
116
Cholecysokinin is produced by?
from I cells in mucosa of small bowel-- \> gallbladder contractions --\>release of bile salts into duodenum (hormone from I cells in mucosa of the SMALL BOWEL. And it causes gallbladder contractions and bile salts to go into the duodenum)
117
Secretin: -produced by? -regulates?
-From duodenum S cells -regulates H20 homeostasis (Secretin= absorbs water when needed, and secretes water when not needed)
118
Gastic inhibitory peptide: -decreases both ______ \_\_\_\_\_ release and \_\_\_\_
decreases both gastric acid release and motility
119
Enteroglucagon: -decreases \_\_\_\_\_
gastric acid and motility (inject Pt with glucagon to relax the bowel)
120
Stomach: -Fx? -Carbs are broken down via ? -Acid produced?
-fx: Digestion -Carbohydrates – are broken down by amylase -Proteins – Chief Cells produce Pepsinogen-- \> which is broken down into pepsin (note: pepsinogen DOES not react to acid of the stomach, but Pepsin CAN get broken down by hydrochloric acid of the stomach) -Hydrochloric acid -\*\*Intrinsic factor – B12
121
Pernicious anemia=
=megaloblastic anemia--\> means the parietal cells no longer fx (slow process) , \*pernicious anemia= means intrinsic factor issue that causes poor absorption of B12!!
