CASE ANALYSIS IN PATHOLOGY

Thomas H. Kent M.D.

Professor of Pathology

University of Iowa College of Medicine
Iowa City, Iowa 52242

(+) 1-319-335-8196

The process by which an individual learns a discipline involves learning the basic knowledge of the discipline and practicing application of that knowledge to real situations. Later, one can practice more, refine one’s knowledge base, and even add new discoveries to the discipline. In my medical student days, the practice was mostly oriented toward the discipline (e.g., hundreds of microscopic slides to look at in the pathology laboratory), rather than toward application of the discipline to the practice of medicine. I personally believe that it is useful to learn the basics of each of the basic science disciplines, but most medical students will be better motivated by practical applications that are highly related to the practice of medicine. Another aspect of basic science education that frustrated me as a student was the lack of opportunity to use my new knowledge to solve problems and to present orally to faculty and student colleagues.

In 1969-1970 I had an unusual opportunity to guide a major change in our General and Systemic Pathology courses. We decided to allocate the students’ efforts roughly as follows: two-thirds toward knowledge acquisition, one-fourth toward practice in using the knowledge, and one-twelfth toward development of a limited number of skills (primarily basic laboratory tests). We decided to use real cases for the practice exercises, using four or more per week over two semesters. Each group of 10 students is assigned a faculty facilitator for the semester. The students prepare the cases, present them, and discuss them. The cases are designed so that the students encounter all of the basic disease processes and many of the common organ-related problems in a clinical setting. Cases may be morphology oriented (microscopic slides available to check out), laboratory diagnosis oriented (data provided with the case history or by computer simulation), or both.

Since 1974 we have been using computer simulations for three of the weekly exercises. These work best for syndromes that have a common clinical presentation buy varying underlying pathophysiologic abnormalities that require laboratory tests and clinical procedures to uncover. Anemia, bleeding, and jaundice are the topics currently in use. From an outline of causes of a syndrome, we select representative diseases and then find patient charts to illustrate them. The authoring program uses a mater file of all laboratory tests and clinical procedures available in our hospital, including normal values (numeric values given to the student vary based on a mean and standard deviation), cost, time for completion, and information about the test that is accessible to the student during the simulation. Fases are created from smaller files that contain only the results of tests for which there are abnormal results. ASCII files with history and physical examination and a case summary complete the database that is then compiled to create a patient simulation.

Patients are easy to create — pick a patient with the desired disease, abstract a complete history and physical, and abstract or anticipate every abnormal test and procedure. The computer program that delivers the simulation acts as a blck box that allows the student access to information sequentially on a day by day basis for as many days as it takes to arrie at a diagnosis and treatment. The mean screen contains an outline of tests and procedures organized as they would be in our hospital (e.g., routine screening, chemistry, gastroenterology, radiology). Feedback includes a summary of the case and a comparison of costs, efficient (low number of unnecessary tests), and completeness (high number of necessary tests). The optimum work-up is determined by faculty consensus.

We use our computer simulations in our Case Analysis setting. Each student has a different patient, which is presented to and analyzed by the group. Once developed, the simulations are very cost effective and have provided thousands of educational experiences. Actually, these experiences cannot be duplicated in our hospital, because with live patients we cannot guarantee each student the opportunity to work up patients with a specific disease, nor the opportunity to do it without cluing from the house staff and referring physician.

It is difficult to measure the effect of case-related problem solving on the educational process. It seems right to practice using newly acquired knowledge. The amount and type of practice probably is not very important. Unless the faculty really goofs, the students are going to think it is worthwhile — it’s fun, it gives relevance, and it gives them a chance to participate for a change. I have tried many times to prove the usefulness of practical exercises. The most useful information has been the happiness data, and specific analysis of computerized patient work-ups, which reveals that some information needed to write up the cases in not readily available to the students. A byproduct of our cases, especially the computer simulations, is the familiarization of the students to the categories of the history and physical examination and to the organization of our laboratories. The discovery method seems to speed the learning of morphology, and this is done with no laboratory instruction other than discussion that goes on in the groups as students describe the projected photographs taken from microscopic sides that they have looked at while working up the case. Another outcome that is difficult to quantify is the ability of our students to present clearly a fresh case and give a creditable evaluation of the morphology and laboratory test results.

Pathology lends itself unusually well to the use of case-related exercises. It is easy to put the student in the role of a clinician who needs results from the pathology laboratory. We have ready access to case material and can select patients on the basis of clinical frequency and illustration of basic pathophysiologic abnormalities. Most of the Pathology faculty are comfortable playing the role of either clinician or pathologist.