The Sherlock Holmes Assignment AKA The Unknown Lab  

Objectives                                                          Name____________________

Following this lab exercise and project the student will be able to:

1.  Integrate lab skills and tests to identify an unknown.

2.  Justify the lab procedures used, identification, and treatment of the patient.

3.  Evaluate the patient in light of the unknown identification and patient's immune status.

4.  Determine the proper care and treatment for the patient using and citing valid references.

 Unknown Number______________ 

Patientís Name____________________ 


1.      assess your patientís condition

2.      propose a differential diagnosis from the history

3.       determine the necessary tests for a definitive diagnosis

4.       identify the etiologic agent infecting your patient

5.      propose a treatment and long-term care for the patient

Prepare a chart for your patient. The first page should include the patient history and any relevant research you do with regards to any of your patientís conditions relevant to the history. This page should also include a differential diagnosis.

The second page should include any tests that you determine are necessary for the proper identification and treatment of the patient. You are to order and perform only the necessary tests, you will lose points of you do any tests that are unnecessary or do the shotgun method using every test you have ever done or read about. If there are other tests you feel are necessary, but they can not realistically be performed in our lab, indicate these and why they would be important. In addition to microbiological tests you may want to include orders for a CBC, X-Ray, skin test, etc.

The third page should be a record of every test you performed (and the date), the rationale for doing the test, and the results of the test (and the date the test was completed). Explain how these tests helped to rule out the differential diagnosis.

The fourth page will include a summary of the definitive diagnosis, identification of the etiologic agent, information about the agent, a proposed course of treatment and long-term care.


Step 1 Getting Started (Beginning on this page, you will fill out and turn in these charts showing the logical progressive thinking and lab work you have done along with the final report that should respond to the rubric.)

Before you begin observe your specimen. Using the checklist make important observations from the clinical specimen.

Specimen Checklist


List significant concerns or comments about the specimen source.


Condition of specimen

What characteristics may be important concerning the original specimen? Is there blood? Is it moist? Are there any foreign objects, pus, clots etc?



Time specimen taken


Time Cultured

How recently was the specimen taken and will this have any influence on the results? Are there any transportation concerns regarding this type of specimen and culture?



Differential diagnosis or hypothesis

What are the most likely pathogens found in this type of specimen?


Normal flora

Would you expect to find normal flora present in specimens from this source location? If so, what would be most common?



What types of media are commonly used for this specimen?



Incubation Considerations

Considering the location of the specimen are there any special incubation conditions you should consider?


Step 2           Fill in the table below.

Media Inoculated

Rationale for using this media

Date Inoculated/Date read

Results/ Notes/ Thoughts









































Record the Gram stain reaction of each different colony type found on the media.

Gram Stain (create a number to identify the colonies and mark it on the plate)/ Colony description

Recovered from which plate/On what date

Notes (Is this potentially normal flora? Is this a typical result? Anything unexpected? Does the colony morphology match the Gram stain and media selectivity?)


















Determine the appropriate lab tests you will need to continue the investigation. In addition, if you think there should be other tests, such as a cbc or x-ray, that we can not do, indicate that you would order those tests.

Step 3 Test Results

Lab test

Date inoculated/date read

rationale for lab test

Result and interpretation





































 Step 4 Ė Identification and Sensitivity

Determine the identification of your etiologic agent.

What particular types of pathogenic capabilities (if any) does this pathogen display?

Using the Sanford Guide select at least 8 antibiotics in order to test the sensitivity of the agent. Remember to consider cost, narrow and broad spectrum, target agent, target tissue, and administration as well as any side-effects.

Test the appropriate antibiotics for your particular organism and patient. 

Step 5- Resolution, Treatment and Prognosis

Determine factors concerning your patient that are relevant to resolving the patientís condition. Review the immune status of your patient. Determine future treatment and care of your patient and their unique situation.

 Step 6 Ė Create a patient chart that will be graded with the rubric on the following page.
Grading Rubric for the Unknown Case Report

Using MLA format to create a report with the following components:

Skill or assignment

Grading criteria and points

Your points

Gram Stain

1 point each

Total 6 points

Correctly focusing on the bacteria
Correctly performing the Gram stain
Correctly interpreting the Gram reaction
Correctly interpreting the Cell shape
and arrangement


Culture for Isolation
& Description
Total 4 pts

Correctly isolating colonies by isolation technique (2pts)

Correctly describing the colony type (2pt)



        2 pts                      4 pts                                    6 pts                   8 pts

The report shows evidence of spelling and grammar errors

 No spelling and grammar errors exist.

The report displays uniform formatting, proper grammar and spelling.

The report displays no errors and a high level of appropriate scientific vocabulary creatively presented.



Analysis of Patient History

The patient history was included.

The patient history was analyzed with regards to significant factors.

The patient history was analyzed using outside sources and relevant data.

The patient history was thoroughly analyzed integrating excellent supportive resources.




and proper selection and performance of tests

A diagnosis is provided lacking some essential tests or tests were performed incorrectly.

A diagnosis with supporting data and tests are included but the inadequate differential diagnoses
resulted in reliance on research without data or appropriate testing.

A reasonable list of potential differential diagnoses was evaluated. The final diagnosis was explained & supported. The appropriate tests were performed correctly.

A differential diagnosis, evaluative criteria to eliminate unlikely agents or causes, and a final diagnosis is explained and supported with properly performed tests. No nonessential tests were done.



Normal Flora

& Immune Status

No discussion of the immune status or normal flora of the patient.

Incorrect discussion of the immune status and/or the normal flora of the patient.

Discussion of the immune status and normal flora of the patient.

Discussion of the immune status and normal flora were integrated into the diagnosis and treatment.



Patient Care Strategy and Treatment & Prognosis

A patient strategy, 
treatment and  prognosis were included with little or no research indicated.


The patient strategy and treatment include a holistic perspective.
A prognosis is hypothesized using researched information.

A holistic patient care strategy and treatment are suggested with supportive data and a well integrated prognosis.

A long term, holistic patient care strategy and  treatment considering various options and effectiveness was developed with regards to a well- supported prognosis.






Date last updated  

11/21/2007 ©Janet Fulks

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Bakersfield College | Kern Community College District | Janet Fulks
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Date last updated 11/23/2011
©Janet Fulks