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Final Project

Introduction

The Final Lab Project is an active-learning, problem-based activity that enables you to work collectively in a small group to diagnose an infectious disease and apply what was learned in this course. The goal of this final project is for you and your lab partners as a group to:

1. Come up with a valid diagnosis of the type of infectious disease seen in your case study and identify the bacterium causing that infection; and

2. Support your group’s diagnose based on:

a. Any relevant facts in the patient’s history.(A reliable on-line source will be used to support this.)
b. The patient’s signs and symptoms. (A reliable on-line source will be used to support this.)
c. Each of the individual lab tests given in your case study.
d. All microbiological lab tests you performed as part of the project.

The due date for this report can be found on the class calendar. Remember, you are working as a group to solve a problem.  Your grade for this lab is based on the completeness of your report and written evidence of the critical thinking process that went into making and supporting your diagnosis, therefore, it is critical that all members of the group participate, question any conclusions being made by the group, and contribute to the report. Remember, you are trying to convince your instructor that you understand how the diagnosis was made by supporting that diagnosis with data. Your group will work together to write the report and submit one hard copy of that report for your group. Part of your grade will be based on evaluation of your work by your team members.

You will be working in groups of 3. Your group will first choose one of the unknown bacteria provided by your instructor. Look your unknown number up in the instructor’s case study key to determine which case study goes with your unknown.

 

Each member of the group must:

1. Print a copy of the rubric from the link above.

2. Print and fill out a copy of the Team Member Evaluation Form from the link above.

3. Staple them together and hand them in to me the day your Final Lab Project Lab Report is due.

 

For more information on writing your Lab Report, see Course evaluation for Lab (Core labs, case studies, lab quizzes) under Course Info in the menu of my BIOL 230 website or on your course Blackboard site.

 

Your name:

Your unknown number:

Your case study letter:

Your lab section:

Others in your group:

 

 

Be sure to handle all the bacterial cultures you are using in lab today as if they are pathogens!  Be sure to wash and sanitize your hands well at the completion of today’s lab.

 

Case Studies

 

Case Study A

  A 69 year old male with a history of recurring urinary tract infections and multiple antibiotic therapies presents with frequency and urgency of urination, dysuria, suprapubic discomfort, lower back pain, and a temperature of 99.9°F. A complete blood count (CBC) shows 18,000 white blood cells per µL with a left shift. A urine dipstick shows a positive leukocyte esterase test, a positive nitrite test, 30mg of protein per deciliter, and red blood cells in the urine. Microscopic examination of the urine shows 4-9 white blood cells and 15-19 bacteria per high-power microscopic field.

 

Case Study B

A hospitalized 60 year old female with an indwelling urinary catheter and multiple antibiotic therapies presents suprapubic discomfort, lower back pain, and a temperature of 102°F. A complete blood count (CBC) shows a total of 20,000 white blood cells per µL with a left shift. A urine dipstick shows a positive leukocyte esterase test, a negative nitrite test, 30mg of protein per deciliter, and red blood cells in the urine. Microscopic examination of the urine shows 3-7 white blood cells and 16-20 bacteria per high-power microscopic field.

Case Study C

A 61 year old male who is diabetic and a smoker was admitted to the hospital with a leg wound that is not healing. He appears confused and anxious, has a temperature of 101° F, a heart rate of 130 beats per minute, a respiration rate of 42 breaths per minute, a blood pressure of 90/40 mm Hg, a urine output of only 110 cc for the last 8 hours, and a total white blood cell count of 2500/µL. A blood culture is taken.

Case Study D

A 78 year old female who for several days had a severe cough and chest pain when breathing deeply, is admitted to the hospital. Symptoms include confusion and agitation, difficulty in breathing, peripheral edema, and shaking and chills. She has a temperature of 96.1° F, a heart rate of 112 beats per minute, a respiration rate of 45 breaths per minute, a blood pressure of 105/60 mm Hg, and a total white blood cell count of 13,000/µL. A blood culture is taken.

Final Project Lab Report

Each member of the group must:

1. Print a copy of the rubric from the link above.

2. Print and fill out a copy of the Team Member Evaluation Form from the link above.

3. Staple them together and hand them in to me the day your Final Lab Project Lab Report is due.

 

Click Here to Print a PDF Copy of Your Final Project Lab Report

Procedure and Results

 

 1. Patient’s history and predisposing factors

Read the case study. Explain how any relevant parts of the patient’s history contributed to your final diagnosis as to the type of infectious disease seen here. You are urged to use the computers in lab to search reliable medically oriented Internet sources to support this. Reliable sources you might consider are Medscape (http://emedicine.medscape.com/infectious_diseases) and The Centers for Disease Control and Prevention (CDC) at http://www.cdc.gov/. Cite any sources you use at the end of this Patient's History section in APA style (http://www.apastyle.org/).

The patient's history should suggest a general type of infectious disease that is present, such as a urinary tract infection, a wound infection, gastroenteritis, pharyngitis, pneumonia, septicemia, etc. Do not look up the bacterium you eventually identify as the cause of this infectious disease. You don't know the causative bacterium at this point. You need to determine the general type of infection in order to determine what microbiological tests to perform to identify the bacterium causing the infection. Search at least one medically-oriented reference article from a reliable site such as Medscape and use this article to support your diagnosis of the type of infectious disease seen here. Don't forget to cite any sources you used in APA style directly under this Patient's History and Patient's Symptoms sections of this Lab Report.

 

2. Patient’s signs and symptoms

Read the case study. Explain how the patient’s signs and symptoms contributed to your final diagnosis as to the type of infectious disease seen here. You are urged to use the computers in lab to search reliable medically oriented Internet sources to support this. Reliable sources you might consider are Medscape (http://emedicine.medscape.com/infectious_diseases) and The Centers for Disease Control and Prevention (CDC) at http://www.cdc.gov/. Cite any sources you use at the end of this Patient's Symptoms section in APA style (http://www.apastyle.org/). Also see appendix F (SIRS and Sepsis) in your lab manual for an indication of whether or not the patient has SIRS.

The patient's signs and symptoms should suggest a general type of infectious disease that is present, such as a urinary tract infection, a wound infection, gastroenteritis, pharyngitis, pneumonia, septicemia, etc. Do not look up the bacterium you eventually identify as the cause of this infectious disease. You don't know the causative bacterium at this point. You need to determine the general type of infection in order to determine what microbiological tests to perform to identify the bacterium causing the infection. Search at least one medically-oriented reference article from a reliable site such as Medscape and use this article to support your diagnosis of the type of infectious disease seen here. Don't forget to cite any sources you used in APA style directly under this Patient's History and Patient's Symptoms sections of this Lab Report.t.

 

3. Results of laboratory test given in the case study

List each lab test given and explain how the results of that test helps to contribute to your final diagnosis.  Refer to appendix C (Complete Blood Count), appendix D (Urinalysis), and appendix F (SIRS and Sepsis) in your lab manual.

 

4. Gram stain

Give the Gram reaction (Gram-positive or Gram-negative and how you reached this conclusion) and the shape and arrangement of the unknown you were given. State how this contributed to your choice of microbiological tests and/or media to use next. The Gram stain is discussed in Lab 6. If the result of the arrangement is inconclusive after seeing Gram-positive cocci, try doing the catalase test described in Lab 8 and state specifically how the results of the catalase test helped to confirm the arrangement.

Make sure you check your Gram stain results with your instructor before determining which microbiological lab tests you will perform.

 

5. Based on the results of your Gram stain, determine which of the following isolation media you will inoculate. Refer back to Labs 12, 14, and 15 to help determine your selection.

a. MacConkey agar (Lab 12)
b. Blood agar with NB disc (Lab 15)
c. Mannitol salt agar (Lab 15)
d. Bile esculin agar (Lab 14)

Also inoculate a tube of Trypticase soy broth (TSB) with your unknown to be used next time for antibiotic susceptibility testing.

Inoculate each medium you chose, making sure to streak all petri plates for isolation. Incubate the plates upside down and stacked in the petri plate holder on the shelf of the 37°C incubator corresponding to your lab section. Incubate the TSB and Bile esculin agar tube (if used) in your test tube rack on the shelf of the 37°C incubator corresponding to your lab section.

 

Isolation Results

Explain why you chose to use or not use each of the isolation media.

 

a. Maconkey agar (Lab 12)

Why did you choose to use or not use this medium?

If you used this medium, describe the results of the MacConkey agar plate you inoculated with the sample from the patient.State specifically how this contributed to your decision as to what bacterium is causing the infection.

 

b. Blood agar with NB disc.(Lab 15)

Why did you choose to use or not use this medium and disc?

If you used this medium, describe the results of the Blood agar plate you inoculated with the sample from the patient. State specifically how this contributed to your decision as to what bacterium is causing the infection.

 

 c. Mannitol salt agar (Lab 15)

Why did you choose to use or not use this medium?

If you used this medium, describe the results of the Mannitol salt agar plate you inoculated with the sample from the patient. State specifically how this contributed to your decision as to what bacterium is causing the infection.

 

 d. Bile esculin agar (Lab 14)

Why did you choose to use or not use this medium?

If you used this medium, describe the results of the Bile esculin agar you inoculated with the sample from the patient. State specifically how this contributed to your decision as to what bacterium is causing the infection.

 

6. Based on the results of your isolation media used in step 5 above, determine which of the following media you will inoculate or tests you will perform. Refer back to Labs 12, 14, and 15 to help determine your selection of media/tests and how to correctly perform the lab procedures.

a. Oxidase Test (Lab 12)
b. Cetrimide agar (Lab 12)
c. EnteroPluri-Test (Lab 12)
d. SF broth (Lab 14)
e. DNase agar (Lab 15)
f. Coagulase test (Lab 15)
g. Bauer-Kirby antibiotic susceptibility testing on Mueller-Hinton agar (Lab 19)

 

Incubate the plates upside down and stacked in the petri plate holder on the shelf of the 37°C incubator corresponding to your lab section. Incubate the tubes in your test tube rack on the shelf of the 37°C incubator corresponding to your lab section.

 

Results of Additional Lab Media or Lab Tests Performed

Explain why you chose to use or not use each of the following tests or media.

 

a. Oxidase test (Lab 12)

Why did you choose to use or not use this test?

If you used this test, describe the results of the oxidase test and state specifically how this contributed to your decision of media to use.

 

 b. Cetrimide agar (Lab 12)

Why did you choose to use or not use this medium?

If you used this medium, describe the results of the Cetrimide agar and state specifically how this contributed to your decision as to what bacterium is causing the infection.

 

c.EnteroPluri-Test (Lab 12)

Why did you choose to use or not use this test?

Using your Enterotube®II, identify the unknown you were given.

1. In the table below, put a (+) or a (-) in the Result row for each test.
2. Add up the value of each positive test in a group and put that number in the code for each group.
3. The 5 digit number is the CODICE number. Look that number up in the Codebook and identify your unknown.

 

 

Group 1

Group 2

Group 3

Group 4

Group 5

Test

Glucose

Gas

Lysine

Ornithine

H2S

Indole

Adonitol

Lactose

Arabinose

Sorbitol

VP

Dulcitol

PA

Urea

Citrate

 

Value

 

4

 

2

 

1

 

4

 

2

 

1

 

4

 

2

 

1

 

4

 

2

 

1

 

4

 

2

 

1

 

Result

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Code

 

 

 

 

 

 

CODICE NUMBER:

Genus and species from the EnteroPluri-Test: _____________________________________

 

d. SF broth (Lab 14)

 Why did you choose to use or not use this medium?

If you used this medium, describe the results of SF broth and state specifically how this contributed to your decision as to what bacterium is causing the infection.

 

e. DNase agar (Lab 15)

Why did you choose to use or not use this medium?

If you used this medium, describe the results of DNase agar and state specifically how this contributed to your decision as to what bacterium is causing the infection.

 

f. Coagulase test (Lab 15)

Why did you choose to use or not use this test?

If you used this test, describe the results of Coagulase test and state specifically how this contributed to your decision as to what bacterium is causing the infection.

 

g. Bauer-Kirby antibiotic susceptibility testing on Mueller-Hinton agar (Lab 19)

 

Gram-Positive Unknown
Disc code Antimicrobial agent Zone in mm R I MS S
AmC-30 amoxicillin/
clavulanic acid
         
CTX-30 cefotaxime          
FOX-30 cefoxitin          
CIP-5 ciprofloxacin          
CC-2 clindamycin          
E-15 erythromycin          
K-30 kanamycin          
OX-1 oxacillin          
SXT sulfamethoxazole
+ trimethoprim
         
Te-30 tetracycline          
TZP110 piperacillin/tazobactum          
Va-30 vancomycin          

R = Resistant
I = Intermediate
MS = Moderately Susceptible
S = Susceptible

 

 

Gram-Negative Unknown
disc code antimicrobial agent zone in mm R I MS S
An-30 amikacin          
AMC-30 amoxicillin/
clavulanic acid
         
AM-10 ampicillin          
CB-100 carbenicillin          
CTX-30 cefotaxime          
FOX-30 cefoxitin          
CIP-5 ciprofloxacin          
GM-10 gentamicin          
K-30 kanamycin          
SXT sulfamethoxazole
+ trimethoprim
         
Te-30 tetracycline          
TZP-110 piperacillin/tazobactum          

R = Resistant
I = Intermediate
MS = Moderately Susceptible
S = Susceptible

 

Final diagnosis:

What infectious disease does the patient have?

 

What is the name of the bacterium causing this infectious disease?

 

Based on your Bauer-Kirby results, what antibiotics might be effective against this bacterium?

 

 Using at least one reliable Internet source, your Lab Manual, and Unit 2 (Bacterial Pathogenesis) of my Lecture Guide, write a one to two page description of your unknown, including a description of the bacterium, the types of infections it can cause, possible virulence factors that contribute to the bacterium’s pathogenesis, and predisposing factors that might have contributed to the patient in your case study being at increased risk for an infection with that bacterium.

 

Print a PDF of Final Project Lab Report

Contributors

  • Dr. Gary Kaiser (COMMUNITY COLLEGE OF BALTIMORE COUNTY, CATONSVILLE CAMPUS)