Robbins Flashcards
(166 cards)
1
Q
1-2 decades of life, Extremely painful, recurrent sores, associated with IBD, Celiac, and Behcet disease?
A
Aphthous ulcers
2
Q
Shallow hyperemic ulcerations covered by gray exudate and surrounded by rim of erythema?
A
Aphthous ulcer
3
Q
Recurrent oral ulcers, genital ulcers, and uvietis?
A
Behcet disease
4
Q
Superficial, curdlike exudate gray/white inflammatory membrane composed of matted organisms in a fibrinosuppurative exudate that can be easily scraped off?
A
Oral candidiasis
5
Q
Submucosal nodular lesion that forms due to chronic irritation causing reactive CT hyperplasia?
A
Fibroma
6
Q
Pedunculated, richly vascularized, red-purple masses usually found on gingiva of children, adults, pregnant women?
A
Pyogenic Granuloma
7
Q
“White patch or plaque that cannot be scraped off and cannot be characterized clinically or pathologically as any other disease?
A
Leukoplakia-> considered pre-cancerous until proven otherwise
8
Q
Red velvety eroded area that is fat and depressed relative ti the surrounding mucosa?
A
Erythroplakia-> High risk of Cancer than Leuloplakia
9
Q
Most common risk factor for Leukoplakia and erythroplakia?
A
Smoking
10
Q
What are the two major RF for Oral SCC?
A
Smoking-> P53 + NOTCH1 mutations
HPV16-> p16 mutation + located in tonsillar crypts and base of tongue (better prognosis)
11
Q
Mumps virus is known to causes inflammation of what 3 organs?
A
Parotid gland-
Orchitis-> sterility
Pancreatitis
12
Q
Toddlers, fluctuant swelling of lower lip, cyst with Mac infiltrations that may change in size is association with meals?
A
Mucocele
13
Q
Bacterial sialadenitis is often predisposed by what factors and caused by what organisms?
A
RF= Stones, dehydration, injury, phenothiazine use Organisms= S, aureus + Strep viridans
14
Q
The likelihood that a salivary gland tumor is malignant is inversely related to what?
A
ITS SIZE
submandibular- 45% malignant
Sublingual= 90% malignant
15
Q
What are the 2 most common salivary tumors?
A
Pleomorphic adenoma (50%) Warthin tumor (5%)
16
Q
Most common Malignant tumors?
A
Mucoepidermoid carcinoma (15%) Acinic cell carcinoma (6%) Adenocarcinoma NOS (6%)
17
Q
Painless, slow growing, mobile parotid gland mass?
A
Pleomorphic adenoma= consist of ductal and myoepithelial cells
18
Q
Parotid mass displaying Heterogenic histology with evidence of cartilage and bone?
A
Pleomorphic adenoma
19
Q
parotid gland Tumor containing cords, sheets or cysts lined by squamous, mucous, or intermediate cells?
A
Mucoepidermoid carcinoma
20
Q
Cystic growth arising around crown of unruptured tooth resulting in degeneration of dental follicle, lined by squamous epithelium as a sign of Chronic inflammation?
A
Dentigerous cysts
21
Q
Ora cyst that is locally aggressive and high recurrence rate?
A
Odontogenic keratocyst
22
Q
Benign cystic tumor of parotid gland with abundant lymphocytes and Germinal centers?
A
Warthin tumor
23
Q
Parotid gland tumor consisting of mucinous and squamous cells commonly damaging Facial nerve?
A
Mucoepidermoid carcinoma
24
Q
Swollen, painful, parotid gland with purulent discharge. MCC?
A
Acute Sialadenitis= S. aureus
25
Episodic pain and swelling of parotid gland prior to eating a meal. MCC?
Chronic Sialadenitis== Due to Sialotlith (STONE)
26
Middle aged female, slow growing, painless, movable, firm mass for years NOW rapidly growing?
Pleomorphic Adenoma--> Becoming Malignant Carcinoma
27
Round, well circumscribed, non tender, movable rubbery mass on 50 yo female parotid gland. What is the most likely pathology?
Pleomorphic Adenoma= Encapsulated + Ductal or cystic formations with Epithelium + Myxoid or chondroid matrix (2 Germ layers)
28
MC complication of Pleomorphic adenoma treatment?
Facial nerve injury
29
60 yo male smoker, with Slow growing mass, painless, firm @ the tail of Parotid gland?
Warthins tumor
30
What is the histology of Warthins tumor?
Cystic spaces lined by double layer of oncocytes, and Prominent LYMPHOID STROMA + GERMINAL CENTERS
31
59 yo female, parotid gland mass that is asymptomatic. Biopsy shows mixture of mucous and squamous cells. What is the prognosis of this mass dependent on?
Mucoepidermpoid Carcinoma=
GRADE
location
Stage
32
What esophageal abnormalities are discovered shorty after birth due to regurgitation during feeding?
Atresia
Fistulas
Duplications
33
Atresia are often associated with Eso-Tracheal fistulas causing what pathologies?
Aspiration pneumonia
Suffocation
Severe fluid and electrolyte imbalance
34
Characterized by the triad of:
1. incomplete LES relaxation
2. Increased LES tone
3. Esophageal aperistalsis
```
Esophageal Achalasia (Chalasia= Relaxation)
primary-> idopathic
```
35
What is the MCC of secondary Esophageal Achalasia?
Chagas Dz= Trypanosoma cruzi
36
What is the pathogenesis of Chagas disease causing Achalasia?
Trypanosoma cruzi destroys the myenteric plexus= failure of LES relaxation + esophageal dilation
37
What are some other causes of Achalasia like disease?
```
Diabetic autonomic neuropathy
Malignancy
Amyloidosis
Sarcoidosis
Polio
```
38
What are the 2 MCC of Esophageal varices?
Cirrhosis
| Schistosomiasis
39
MCC of death of advanced Cirrhosis patient?
Esophageal varices
40
Chronic alcoholics and bulimics present with Hematemesis due to GEJ tears?
Mallory-Weiss tears = Linear + longitudinally oriented tears heal rapidly
41
Transmural esophageal tears and Mediastinitis caused by Chronic vomiting?
Boerhaave syndrome= (Cutaneous Emphysema)
42
What conditions decrease LES tone and contribute to GERD?
```
Tobacco
ETOH
Obesity-> increase Abdominal pressure
CNS depressants
Pregnancy
Hiatal hernia
Delayed gastric emptying
Increased Gastric volume
```
43
What can be seen on the Esophagus during mild or Severe GERD?
```
Mild= Hyperemia (redness)
Severe= Eosinophils + PMNs + Basal zone Hyperplasia
```
44
Pt with dysphagia, feeding intolerance, and large # of Eosinophils in esophageal biopsy far from GEJ?
Eosinophilic Esophagitis
45
Endoscopy shows patches of red, velvety mucosa extending upward from GEJ will most likely reveal what on microscopy?
Metaplastic Columnar cells with GOBLET cells= Barrett's esophagus
**increased risk for Adenocarcinoma
46
MC esophageal neoplasm in US?
Adenocarcinoma= Due to GERD
47
Chronic alcoholic presents with Dysphagia, Odynophagia, wght loss, chest pain, and vomiting needs to be checked for what?
Adenocarcinoma= Barrett esophagus
48
What are the risk factors for Esophageal SCC?
```
ETOH
Tobacco
Poverty
Achalasia
Plummer-Vinson syndrome
HOT TEA
previous radiation
```
49
What is the lymph node spread for Esophageal SCC?
upper 1/3= Cervical LN
middle 1/3= Thoracic LN
Lower 1/3= Celiac LN
50
Esophagitis is most frequent in what kind of patients?
Immunocomprimised pts= Candidiasis is sign of HIV-> AIDS
51
What are foveolar cells?
Mucus secreting cells in the Antrum (cardia) of stomach
52
What factors lead to developing Gastritis/ damage stomach mucosa?
```
H pylori
NSAIDS
ETOH
Radiation/ Chemo
Aspirin
Smoking
Hyperacidity
Duodenal-gastric reflux
```
53
What is the significant finding indicating inflammation of the Stomach lining?
PMNs above basement membrane--> IN direct contact with Epithelial cells
54
What are the defensive forces that protect the stomach lining?
```
Mucus
HCO3 in mucus
Mucosal Blood flow
Apical membrane transport
Epithelial regeneration
Elaboration of PGs
```
55
What are the mCC of focal acute peptic injury?
NSAIDs
| STRESS--> hypoxia induced
56
Peptic injury most commonly occurring in critically ill pts with Shock, sepsis, or severe trauma?
Stress Ulcers--> Systemic Acidosis
57
Peptic injury occurring in the proximal duodenum associated with severe burns or trauma?
Curling Ulcers
58
Peptic injury arising in stomach, duodenum, or esophagus of persons with intracranial disease with High incidence of perforations?
Cushing Ulcers-->
| Intracranial injury= Increased Vagus stimulation= Acid Hypersecretion
59
What are the protective affects of PGs?
Induce HCO3 secretion
| Enhance mucosal blood flow
60
Patient with nausea, vomiting, and "Coffee ground" hematemesis?
Gastric Ulcer
61
Nausea, upper abdominal discomfort, vomiting, but no Hematemesis?
Chronic Gastritis
62
MCC of chronic + atrophic?
```
Chronic= H pylori
Atrophic= Autoimmune
```
*less common= Radiation or Chronic bile reflux
63
What manifests as predominately antral gastritis with HIGH acid production despite Hypogastrinemia?
H pylori infection= increased risk for Duodena ulcers and ANTRAL gastritis
64
What are the four virulence factors of H pylori that allow it to infect the stomach?
```
Flagella= confers motility in mucus
Urease= generates NH3 from Urea to Lower pH
Adhesions= adhere to foveolar cells
Toxins= Cytotoxin-associated gene A (CagA) increases risk for ULCERS + CANCER
```
65
Chronic antral H pylori gastritis may progress to Pangastritis resulting in multifocal atrophic gastritis with Reduced acid secretion which Increases risk of what?
Metaplasia--> ADENOCARCINOMA
66
What tests can be used to detect H pylori infection?
Biopsy to identify organism or PCR
Serology for Anti- H pylori antibodies
Fecal bacterial detection
Urea breath test
67
What antibodies can be detected in serum and gastric secretions in autoimmune gastritis?
Antibodies to Parietal cells and Intrinsic factor
68
```
Gastric disorder characterized by
Reduced serum Pepsinogen I levels
Antral endocrine cell Hyperplasia
V B12 deficiency
Defective gastric acid secretion (achlorhydria)?
```
Autoimmune Gastritis
69
What is the pathogenesis for the findings in Autoimmune Gastritis?
Antibodies destroy Parietal cells
Reduced HCl = Increased Gastrin release
Increased Gastrin= Hyperplasia of antrum G cells
Reduced IF= V B12 def= megaloblastic anemia
Chief cell loss= Reduced Pepsinogen
70
What is often associated with both Achlorhydria and pernicious anemia?
Autoimmune Gastritis
71
Contrast the difference in location differences btwn H pylori and AI gastritis?
H pylori= ANTRUM
| AI= BODY and FUNDUS
72
```
Gastic pathology associated with:
PMNs and Subepithelial plasma cells
Increased Acid secretion
Normal Gastrin release
Hyperplastic/inflammatory polyps
What is RF and sequelae?
```
H pylori induced Antral Gastritis
RF: Low SE status + poverty + Rural areas
Sequelae: Peptic Ulcers + adenocarcinoma + Lymphoma
73
```
Gastric pathology defined by:
Lymphocytes and Macs invasion
Decreased HCl production
Increased Gastrin
Neuroendocrine hyperplasia
What is the Dx test and Sequelae?
```
Autoimmune Gastritis
Dx test: Antibodies to Parietal cells (Proton pump or IF)
Sequelae: Atrophy, Pernicious anemia, Adenocarcinoma, Carcinoid tumor
74
What are the MC sites of PUD?
Antrum + 1st part of Duodenum
75
PUD occurring in the small intestines of a child is often secondary to what?
Gastric heteropia within-->Meckel Diverticulum
76
What is the fundamental cause of PUD?
Gastric Hyperacidity= MCC by H pylori
77
What are some known Cofactors for developing PUD?
```
chronic NSAIDS
Cigarettes-> impairs blood flow/ healing
ETOH
HD Corticosteroids= Inhibit PG synthesis/healing
Hyperparathyroidism
Chronic Renal failure
```
78
What is the pathogenesis for Hyperparathyroidism and Chronic Renal failure causing PUD?
HYPERCALCEMIA= stimulates Gastrin release
79
MC in the proximal duodenum, sharply punched-out lesion with smooth and richly vascularized granulation tissue?
PUD
80
Pt complains of epigastric burning or aching, anemia, with pain occurring 1-3 hrs after meals and Worse at NIGHT. N/V and bloating?
PUD
81
Causes increased Gastric production and MALT transformation into Lymphoma?
H pylori gastritis
82
Found in patients with Hx of Familial adenomatous polypsosis and increased risk with proton pump inhibitors (due to Increased Gastrin)?
Fundic gland Polyps
83
What are the MC risk factors for Gastric adenocarcinoma?
Mutations- CDH1 + APC genes
H pylori
EBV--> Diffuse with Lymphocytic infiltrates
84
CDH1 mutation increased the risk of what type of gastric neoplasia and why?
Adenocarcinoma
| Mutation= LOSS of E-cadherins
85
Lauren classification of Gastric adenocarcinoma:
1: Elevated mass with heaped boarders and central ulceration
2. Dischohesive cells with SIGNET RING cells + Desmoplastic reaction causing Loss of RUGAE = Linitis plastic?
1. Intestinal Adenocarcinoma-> closely associated with Atrophic gastritis
2. Diffuse Adenocarcinoma= "leather bottle"
86
What are the most powerful diagnostic indicators of Gastric adenocarcinomas?
Depth of invasion-> Locally invades
| Nodal/ distant mets
87
What are the most common types of Lymphomas in the GI tract?
Diffuse Large B cell
| MALTomas
88
Tan intramural or submucosal masses that elicit intense desmoplastic reaction causing kinking or bowel obstruction and histology shows trabeculae/ sheets of uniforms cells with Stippled nuclei?
Carcinoid tumor
89
Often causes Cutaneous flushing, sweating. bronchospasms, colicky abdominal pain, diarrhea, and right sided cardiac valvular fibrosis?
Carcinoid tumor secreting Vasoactive substances
90
What is the pathogenesis of 75-80% of Gastrointestinal stromal tumors (GIST)?
cKIT or PDGFRA mutations--> tyrosine Kinase
| **Arises from Interstitial cells of CAJAL
91
What is the most important factor when i comes to Carcinoid tumors?
LOCATION
Small intestines= Malignant
Appendix= Benign
92
Small flask-like outpouchings that occur in btwn taeniae coli of the Sigmoid colon most commonly in pts >60yo?
Diverticulosis
93
Thinning of the diverticula walls and fecal entrapment can lead to?
Diverticulitis --> perforation
94
Often asymptomatic, or 60 yo male with Low fiber diet with intermittent cramping, lower abdominal pain, constipation, and diarrhea?
Diverticulosis
95
Chronic condition of bowl resulting from inappropriate mucosal immune activation?
Inflammatory bowel disease
96
Inflammation limited to COLON and RECTUM, and extends only into mucosa and submucosa?
Ulcerative colitis
97
Transmural inflammation of Ileum leading to Strictures?
Crohn disease
98
Skip lesions, transmural inflammation, ulcerations, and fissures?
Crohn disease
99
Continuous colonic involvement beginning at RECTUM, and pseudo polyps and ulcer formations?
Ulcerative colitis
100
What are the genetic links for Crohns vs. ulcerative colitis?
```
Crohn= 50% rate in monozygotic twins
UC= 16% rate in monozygotic twins
```
101
What is the gene responsible for increase susceptibility to Crohns disease?
NOD2= protein binds bacterial peptidoglycans and activated NF-kB
102
What immune cells are the primary target of Crohns disease therapy?
Th1 and Th17 cells
| **Th1 secrete IFN= activates Macs= Granulomas
103
What cells are overreacting in ulcerative colitis?
Th2 --> overproduce IL-13
104
What epithelial defects are associated with Crohsna and UC?
Defective intestinal epithelial tight junctions= NOD2
| Paneth Cell granules= abnormal in Crohns
105
How do appendicitis and smoking affect Crohns and UC?
```
Appendicitis= reduced risk of UC
Smoking= Reduced risk of UC + increased Crohns
```
106
Most common site of Crohn disease involvement?
Terminal Ileum
Ileocecal valve
Cecum
107
What is the earliest lesion in Crohns disease?
Aphthous ulcer--> Cobblestone appearing--> Fissures between mucosal folds
108
Transmural inflammation of Crohns causes what kind of reaction in Small bowel wall?
Wall thickening
Submucosal fibrosis
hypertrophy of muscularis propria
Creeping fat= strictures or perforations
109
What are the microscopic features of Crohn disease?
Crypt abscess= PMNs within crypt + ulcers + branching crypts + GRANULOMAS
110
Paneth cell metaplasia in Left colon + noncaseating granulomas are a hallmark of what disease?
Crohn disease
111
Pt with mild NON-bloody diarrhea + fever, and abdominal pain?
Crohn disease
112
What are the Extraintestinal manifestations of Crohn disease?
```
Uveitis
Migratory polyarthritis
sacroiliitis
ankylosing spondylitis
Ertythema Nodosum
Clubbing
```
113
Always involves Rectum and ascends into colon?
Ulcerative colitis
114
Colonic mucosa appearing as granular, broad-based ulcers, mucosal atrophy, NO Strictures?
Ulcerative colitis
115
Pt with ulcerative colitis develops a condition caused by inflammation and inflammatory mediators damaging muscularis mucous and disturb the neuromuscular function?
Toxic megacolon
116
What are the histological features of Ulcerative colitis?
```
Generalized superficial Inflammation
Crypt abscesses
Crypt distortion
Epithelial metaplasia
NO GRANULOMAS
```
117
Pt with attacks of Bloody diarrhea, expulsion of stringy mucoid material, and Lower abdominal pain and cramping relieved by defecation?
Ulcerative colitis
118
30 yo white female, abdominal cramps, bloody stool for 6 mo, wght loss, oral ulcers, blood on rectal exam and Fistula draining foul smelling fluid?
Crohn Disease
119
What is the DDx for Toxic megacolon?
1. C. difficile pseudomembranous colitis
2. IBD (UC or Crohn dz)
3. Obstruction: tumor or inflammation
4. Functional disorder associated with psychiatric disease or meds
5. Chagas Disease
120
What is associated with failure of urorectal septum formation in cloaca (wk7) or failure of anal membrane opening (wk8) or Down syndrome?
Anorectal stenosis or Atresia
121
Male 60 yo, with chronic gastritis and atrophy/ intestinal metaplasia is diagnosed with gastric adenoma. The risk of this lesion becoming an adenocarcinoma is related to what?
SIZE= >2cm = Higher risk
122
Familial diffuse gastric adenocarcinoma is associated with what genetics?
CDH1 mutation= Loss of E-cadherins
123
Patients with FAP have a mutation in what gene that increases their risk for Intestinal Gastric adenocarcinoma?
APC= deactivates Beta catenin
124
Pt with sweating, redness, colicky abdominal pain, bronchospasms, diarrhea, and Right sided valvular fibrosis?
Carcinoid syndrome
125
75% of GIST have what gain of function mutation and arises from what GI cells?
c-KIT= Tyrosine kinase
| Interstitial cells of Cajal
126
Microscopic examination of intestines reveals atrophy and sloughing of surface epithelial cells but hyperplastic crypts?
Ischemic bowel
127
Older patient with sudden severe abdominal pain, tenderness, N/V, bloody diarrhea, and melanotic stool?
Acute transmural intestinal infarction
| **Decreased bowel sounds-> shock
128
Patient present with rectal bleeding, mucus discharge, and inflammatory lesion on anterior rectal wall?
Solitary rectal ulcer syndrome
| **caused by impaired relaxation of anorectal sphincter
129
5 yo male with rectal bleeding, and prolapsed mass in the rectum?
Juvenile polyp
| **SMAD4 mutation
130
AD disorder characterized by multiple GI hamartomatous polyps in small intestines and mucocutaneous hyper-pigmentation?
Peutz Jeghers syndrome
131
Smooth nodular protrusions of mucosa, most common in Left colon, with SERRATED glands and lots of goblet cells?
Hyperplastic polyps
132
Pre-cancerous colonic lesions in 50 yo patients?
Adenomas
133
Polyp with surface erosions, cystically dilated crypts filled with mucus, PMNs, and debris in a childs rectum?
Juvenile polyp
134
Polyp in small intestine with complex glandular architecture and bundles of Smooth Muscle?
Peutz-Jeghers polyp
135
Pt with intestinal polyps, osteomas of mandible, and desmoid and thyroid tumors?
Gardners Syndrome
136
Pt with intestinal adenomas, CNS tumors
| (medulloblastomas or glioblastomas)?
Turcot syndrome
137
DNA mismatch repair mutation or MSH2/MLH1, causing predominately RIGHT sided sessile serrated adenomas or mucinous adenocarcinomas?
HNPCC
138
APC/WNT pathway mutation causing LEFT sided colonic tubular or villous adenomas or adenocarcinoma?
Sporadic Colon cancer
139
What syndrome was described as a familial clustering of colorectal, endometrial, stomach, ovarian, ureter, brain, small bowel, and skin cancers?
LYNCH syndrome or HNPCC
140
Describe the APC/Beta catenin pathway to colonic adenocarcinoma?
APC is negative regulator of Beta catenin
Beta catenin is part of WNT proliferative pathway
Mutation in APC= Increased Beta catenin
Beta catenin-> translocates into nucleus and activates MYC and cyclin D= Increased Prolif
141
Describe the molecular changes in the adenoma-carcinoma sequence?
Normal= Inherited APC mutation
Second HIT= LOSS of APC= Increased Bcatenin
Adenoma-Early > KRAS mutations
Adenoma Late--> SMAD 2+4 + p53 mutations
Carcinoma- Telomerase mutation
142
What are the Early and Late mutations in the Adenoma-> carcinoma sequence of colon cancer?
```
Early= KRAS
Late= p53
```
143
What is microsatellite instability?
DNA mismatch repair deficiency mutations accumilate in microsatellite repeats
**Silence unless in BAX or TGF-beta encoding sequences
144
What is the molecular changes leading to colonic carcinoma in the mismatch repair pathway?
Normal= Inherited MSH2 + MLH 1 mutations
Sessile serrated adenoma= Microsatellite instability
Carcinoma= BAX & BRAF mutations
145
What kind of tumors are found in the RIGHT vs LEFT colon?
```
Right= polypoid, exophytic, bleeding
Left= Annular + obstructive
```
146
Hyperplastic polyps must be distinguished from what due to their malignant potential?
Sessile serrated polyps
147
What is the difference in cancer transformation timelines btwn FAP and HNPCC?
```
FAP= develop cancer EARLY (<30yo)
HNPCC= Cancer late in life
```
148
Comma shaped organism found in warm waters around Ganges valley in India and Bangladesh causing severe watery diarrhea?
V cholera
149
What are the complication associated with C jejuni infections?
Guillian Barre
Erythema Nodosum
Reactive arthritis= HLA-B27 +
150
G- bacillus, Uncapsulated and nonmotile. Important cause of Bloody diarrhea?
Shigellosis
151
Pt with 6 days of diarrhea that started off watery but changes to Bloody, and complications include Reiters syndrome ("cant pee, see, climb Tree")?
Shigella
152
Primary cause of Travelers diarrhea, Expresses LT that acts similar to Cholera toxin and ST that increases cGMP intracellular?
ETEC (enterotoxigenic E coli)
153
After inadequately cooked ground beef consumption patients develops dysentery and kidney failure caused by what organism that secrete Shiga like toxin?
EHEC (O157:H7)
154
Serotype of normal GI flora that causes bloody diarrhea via invasion of gut epithelium but does NOT produce toxins?
Enteroinvasive E coli
155
Causes gastroenteritis via spread through uncooked poultry and eggs?
Salmonella enteritidis
156
What is the pathogenesis of Salmonella induce gastroenteritis?
* *T3 secretion system transfers Bacterial proteins into M cells
* *Proteins activate host Rho GTPase causing bacterial endocytosis
* *Causes chemoattractant release- PMNs damage mucosa
157
Pt with acute onset of abdominal pain, N/V, bloody diarrhea, progresses to HIGH fever, small maculopapular lesions, and in LLQ?
Salmonella typhi= Typhoid fever
* *Rose spots= maculopapular lesions
* *SCD= Osteomyelitis
158
What is the morphology seen in MCC of antibiotic associated colitis?
C difficile= Pseudomembranes
159
Hospitalized patient with fever, leukocytosis, abdominal pain, cramps, Hypoalbuminemia, watery diarrhea, and dehydration?
C difficile
160
30 yo Pt returning from cruise suffer acute onset of N/V, watery diarrhea and abdominal pain. Fecal culture show no bacterial growth. Most likely diagnosis?
Norovirus infection
161
MCC of severe childhood (6-24mo) diarrhea and related deaths worldwide?
Rotavirus
162
What is the pathogenesis of Rotavirus induced bacteria?
Selectively infects and destroys Mature Enterocytes in small intestines
Villus surface is repopulated by IMMATURE cells causing decreased Absorption= Osmotic diarrhea
163
Nematode that infects intestinal mucosa by ingested eggs that hatch and penetrate mucosa, Circulate to LIVER and cause Abscesses and even Pneumonitis?
Ascaris lumbricoides
164
Larvae lives in fecally contaminated soil and penetrates broken skin. Larvae mature in intestines , release eggs and cause LIFE long auto infections?
Stronglyoides
165
This parasite is the leading cause of IRON deficiency anemia in the developing World?
Hookworms
166
Most common human parasitic infections, resistant to chloride treatment, Decreases Brush boarder enzymes and causes apoptosis of epithelial cells. Causes CHRONIC diarrhea and malabsorption?
Giardia
