n Case 1: At the age of 63 years, Mr. O. had an operation to remove a tumor that obstructed - PowerPoint Presentation

Slide1

n

Case 1:

At the age of 63 years, Mr. O. had an operation to remove a tumor that obstructed his stomach.

The surgeon

resected part of stomach

and

connected

the

remainder part

with

the jejunum

,

bypassing

the un-resected duodenum.

Two years later, Mr. O. developed

chronic diarrhea

, and his weight dropped from

139

to

97

pounds.

On examination he was extremely

thin

,

fatigued

with short of breath and

numbness and tingling

in his hands and feet.

N

Laboratory tests showed a

severe anemia

with large red blood cells (

ovalocytes

) and

hypersegmented

neutrophils

.

Serum levels of

Vitamin A

, and

Carotene

were

depressed

.

Serum

Vitamin B

12

was

undetectable

.

Specific test for

fat contents

in stool analysis revealed

steatorrhea

.

10

9

CFU

of

Bacteroides

fragilis

and

10

6

E.coli

CFU per mL were isolated from small bowel specimens.

N

1- What is your

diagnosis

?

2- What is the

cause of this abnormality

?

3-How can you confirm your answer?

4-What is the

underlying cause

of the numbness

and

tingling

experienced by Mr. O?

5- What is the mechanism of the diarrhea that

established due to this conditions?

n

Case 2:

Mr. R., an 85-year-old resident of a nursing home was visited by E., his 3-year-old granddaughter. The two shared a

fast-food hamburger

for lunch.

One day later, Mr. R had a

watery diarrhea

every 15 to 30 minutes, initially with

small amount of visible blood

. Later that day,

bright red stools

consisting of

pure blood

appeared. Mr. R was hospitalized and a

barium enema

revealed

edema

of the

ascending

and

transverse colon

.

n

Routine stool cultures were

negativ

e for

Salmonella

and

Shigella

. However,

Sorbitol non-fermenting

E.

coli

was identified by Lab as a serotype

O157:H7

.

One day after Mr. R fell ill, E. developed

watery bloody diarrhea

that increased over the next 2 days. When E. began to vomit and her

urine output

appeared to

diminish

, her parents took her to the pediatrician. The

laboratory

reported a

significant decrease

in

platelets

and

red blood cells

, many of which

looked abnormal

.

Serum

creatinine level

was slightly elevated.

N

The patient was treated with

intravenous fluids

and

no antibiotics were given

. No hypertension developed and she was discharged 1 week later due to improvement in the blood count and kidney function test.

1-What is the likely source of infection?

2-Diagnosis of E. case.

3-How can you confirm this diagnosis?

4-By which mechanism does the responsible etiological

agent cause these diseases in Mr. R and E case?

5-What are the principle therapeutic concerns in such case.

N

Case 3:

Mr. L., a 23-year-old patient came to the emergency department because of

jaundice

. For several days he had felt increasingly weak, nauseated, and feverish and had

pain on the right side of his abdomen

. He reported that he had experimented with a variety of oral and injectable drugs. The emergency physician suspected that Mr. L. had acute hepatitis.

The laboratory reported

increased SGPT

,

Alkaline phosphatase

, and

total

and

direct bilirubin

.

N

HBsAg

was detected

in

serum.

Anti-

HBsAg

Antibodies

were negative.

1-By what route might Mr. L. have become infected?

2-What is the period of Hepatitis B infection seen in this

case?

3- How can you confirm your answer?

4-What follow-up tests will be required to determine his

long-term prognosis?

5-What advice can Mr. L be given to avoid further

transmission of infection.

N

Case 4:

An elderly patient is placed on

ampicillin

and develops fever, and

acute diarrhea

with

blood

and

mucus

. Laboratory results of Complete blood count (C.B.C) reported

leukocytosis

and

elevated neutrophils

count.

Which one of the following organisms is the most likely cause of this patient’s diarrhea?

A.

Staphylococcus

aureus

.

B.

Streptococcus pyogenes

.

C.

Clostridium

difficile

.

D.

Clostridium perfringens

.

E.

Bacillus cereus

.

N

Case 5:

A 45-year-old tourist returned from a trip to South America and began having cramps and

diarrhea

. The

watery bowel movements

came rapidly, one after another, and contained

small bits

of

grayish-white stool

. The man was sweaty and nauseated. Upon admission to hospital,

2 liters of fluid were administered intravenously

, which was supplemented by oral fluid. The patient was discharged 48 hours after admission. A

Gram’s negative

non-lactose fermenting

non-halophilic

rods was isolated by

alkaline peptone

media.

Which of the following microbes produces these symptoms?

A.

Vibrio parahaemolyticus

. D.

Helicobacter pylori

.

B. ETEC. E.

Vibrio cholerae

.

C.

Campylobacter jejuni

.