Fourth Year Medical Students are Effective Case Discussion Leaders

Uldis N. Streips Ph.D. and Ronald M. Atlas Ph.D.*

Department of Microbiology and Immunology

University of Louisville School of Medicine
Louisville, KY 40292 U.S.A.

(+) 1-502-852-5365
(+) 1-502-852-7531

*Current position-Dean, Graduate School, University of Louisville, Louisville, KY


Medical seniors have been used extensively as discussion leaders in small group settings for sophomore Medical Microbiology students. There is a benefit for both the seniors and the sophomores. In addition, this obviates the need for faculty discussion leaders.


Clinical case presentation is an integral part of medical education from the preclinical years to clinical studies and postgraduate rounds. We have found that clinical case presentation can be enhanced in the second year Medical Microbiology and Immunology course by bridging the medical education experience between fourth year students and second year students. Fourth year students were used as discussion leaders for small groups of second year students. There is educational value for both student groups.


A straightforward, effective way was instituted to bring fourth year medical students to a basic science setting and develop a mutual learning experience for fourth and second year medical students. Our course in Medical Microbiology and Immunology has extensive clinical correlation by featuring numerous clinically relevant activities throughout the course. In fact, our course only has 58% formal lectures. We do not use a classical problem-based learning (PBL) format. To initiate the 8 clinical case discussions each year, volunteers from the senior class are sought to be leaders for these discussion groups. The response has been excellent and universal. From a class of 142, about 40 volunteered immediately and rarely will anyone refuse if asked later, even without volunteering. A valuable inducement is an agreement with the Associate Dean for Students, whereby a sentence is inserted into every participating senior’s residency application letter stating that this student helped in teaching second year students.

The mechanics for running these sessions are straightforward. Each senior received an envelope with the case to be discussed (see sample case Figures) and instructions for the session, a few days prior to their session, to facilitate preparation. The second year students received the case to read and review the day prior to discussion. The seniors each had a group of 24 students and went through the case in detail, making sure the sophomores understood all the clinical terms, implications of the physical findings, as well as an appreciation for what should be done initially for the patient. Then, through discussion, they helped the group develop a differential diagnosis of each case, not necessarily with microbiology and immunology in mind initially, even though all cases were ultimately course-related in nature. Once the differential diagnosis was finished, more data on the case were provided to the students (either freely or having the sophomores ask for specific tests) to narrow the differential, and the students were ultimately led to the cause of the medical problem. As a variation, the seniors in some of the cases acted as the patient, and the sophomores had to elicit relevant history to reach conclusions about the cause of the medical problem. Next, treatment was discussed and any unique clinical information available to the seniors was introduced. Often, the seniors can relate the development of the case to questions they had seen in the United States Medical Licensing Exam (USMLE) Part 1. Finally, the second year students separated into smaller groups of 4-6 for discussing 3-4 questions relevant to the case and the senior student was a much used facilitator for this exercise. The seniors were also provided a key of preferred answers to these questions. At the end, the second year students turned in their question sheets for course credit. The entire exercise takes about one hour.

Sample case
The sample case is presented in Figure 1 (adapted from Underground Clinical Vignettes1) and the informational material on the case provided for the senior discussion leaders is shown in Figure 2. Figure 3 represents the questions used for discussion on this case. This particular case was deliberately misleading to show the sophomores that clinical findings should not be prejudged. The case was presented when the sophomores had finished immunology in our course and had received a correlation on Streptococcus pyogenes infection and its sequela-induced rheumatic fever and glomerulonephritis.

Figure 1. Discussion Case #3

A 12-y/o female is brought to her pediatrician and complains of headache, chest palpitation, and ringing in her ears, and is found to have generalized edema. She denies any dyspnea, sore throat, skin infection, or fever. On extended and very careful questioning, she admits she had hematuria. On physical exam, her BP is found to be 140/110, she has generalized (including periorbital) pitting edema; jugular venous pressure is normal; the lung base is clear; neither kidney is palpable; there is no evidence of pleural effusions or ascites.

What would you do initially?

Their first inclination during discussion was that this case could be lupus, or glomerulonephritis. On that basis, they ordered from the senior the results for anti-DNA antibody, streptolysin O antibody, as well as bacterial cultures and antibody titers for some viral infections, just to be sure. However, as you can see in Figure 2, all those were negative. The critical finding is serum hypocomplementia. They were also provided with results from the urinalysis as well as micropathology. They then, ultimately, arrived at the diagnosis of idiopathic membrane proliferative glomerulonephritis. This interfaced strongly with pathology, which our sophomores were just beginning, but the seniors knew well. So, there was also correlative, course-bridging teaching that can take place in these types of exercises. A “hidden agenda” in this process is that the seniors also have to review basic sciences to function as “effective” leaders. The seniors often bring clinical material (X-rays, literature) to illustrate cases and provide further integration with the clinical sciences. The questions shown in Figure 3 allow the sophomores to compare the results from this case to diseases they have already learned about in our course, introduce an ethical question on value and necessity of biopsies as well as information on how to do them, and then specifically center on the problem that this patient is experiencing.


An added benefit to this methodology was the interaction between the fourth and second year students. First, the seniors used clinical terminology and intuitive analysis skills, which gave the second year students a look at their own future development. Second, the seniors rapidly realized that the terminology was relatively foreign to the second year students, and they had a look at their future interaction with patients and how they will need to talk to them. Third, the seniors received valuable practice in case presentation before an audience which will help them in future grand round presentations and in teaching, if they choose an academic career. In addition, our medical school has historically sent very few graduates into academic medicine careers and this exposure to teaching may influence more students to consider an academic future.

Both groups of students benefited and moreover, thoroughly enjoyed the exercise. The only difficulty came in arranging the final schedules with the seniors. Some had to drop out because their fourth year rotation would not let them take the time.

Figure 2. Discussion Case #3
(Session Leader Copy)

(Seniors-make sure they understand the symptoms, the medical terms, and the nature of the physical)

A 12-y/o female is brought to her pediatrician and complains of headache, chest palpitation, and ringing in her ears, and is found to have generalized edema. She denies any dyspnea, sore throat, skin infection, or fever. On extended and very careful questioning, she admits she had hematuria. On physical exam, her BP is found to be 140/110, she has generalized (including periorbital) pitting edema (seniors-go over this); jugular venous pressure is normal; the lung base is clear; neither kidney is palpable; there is no evidence of pleural effusions or ascites. (Seniors-go over these to make sure sophomores understand the examination and findings)

What would you do initially?

(Get blood chemistries and check for antibody titers for possible bacterial, or even viral infections; think of immunological problems)

Ask them what they would like to order. If they order:
Urinalysis- fatty casts and oval bodies in addition to heavy proteinuria (explain what this means) Immunology

  • antinuclear antibody-negative,
  • Anti-streptolysin O antibody ? normal
  • Complement-serum hypocomplementia

(if they don’t order, give this result after discussion)
No antibodies to expected infections with bacteria or viruses Chemistries

  • High BUN and serum creatinine
  • Decreased serum albumin;
  • Elevated serum triglycerides

Ask them if they would want to order anything else? If they don’t come up with this, suggest it.

Micropathology-Light microscopy reveals a diffuse glomerular involvement with thickening of capillary walls and enlargement of glomerular tufts, many times in a lobular pattern. Thickening of the capillary wall comes from interposition of mesangial matrix between GBM and endothelial cells which results in a splitting or double contour of the capillary wall, also known as “railroad tracks”. Staining with periodic acid- Schiff reagent or silver stain visualizes this. Immunofluorescence shows coarsely granulated deposits of complexes with complement components. (Seniors: make sure they understand the pathology report)

Identification: membrane proliferative glomerulonephritis, idiopathic.

The clinical diagnosis of this disease cannot be differentiated from other glomerular diseases and may require renal biopsy to diagnose definitively. Membrane proliferative glomerulonephritis should be strongly considered in young patients who demonstrate nephrotic syndrome and hematuria, as did this patient, and whose serum is shown to have hypocomplementia.

Treatment: (They most likely have no idea so discuss this with them). No immediate response to oral steroid therapy, though prolonged therapy may be beneficial in preserving renal function in children. Renal transplant may be necessary though the disease can recur in transplanted kidneys. Within 6-10 years 1/3 of untreated patients progress to chronic renal failure, 1/3 have persistent nephrotic syndrome, 1/3 have persistent non-nephrotic proteinuria or hematuria

An additional variability comes from the seniors themselves. Not all are great teachers, however that does not seem to impede the value of the sessions to the sophomores. Most seniors arrived ahead of time and could not wait to run their session. They all said they would do it again. This year one wanted to participate in all the discussion sessions. For the first time, the second year students were unanimously satisfied with their discussion groups and put high educational value on the exercise. Prior to the use of seniors, our discussion groups rated at 2.8-3.2 on the scale of 1(best) to 5 (worst). For the three years we have used seniors for clinical discussion the rating is consistently between 1.4-1.8. In the yearly course evaluation for the Fall 2000 session a student wrote: “I hope someday I’ll have the knowledge those 4th years have, so I can teach 2nd year students!? The use of seniors to lead discussion for sophomores is self-propagating for future discussion leaders. Also, it is difficult to recruit faculty with the experience and freshness of knowledge that the senior possesses.


This method for using fourth year students in basic science instruction should be equally applicable to other basic science courses, where discussions on clinical material are presented in either PBL or non-PBL formats. Also, this type of presentation allows the instructor to alter the exercise in whatever way is most suitable for the course, while still maintaining the benefits of this direct interaction among the students for mutual learning.


  1. Bhushan, V., Amin, C., Nguyen, H., Fierro, J., Pall, V. and Grimm, A. Case 89. In: Underground Clinical Vignettes: Pathophysiology, Vol. II. Student to Student Medical Publishing, distributed by Blackwell Science, Malden, MA, 1999.

Figure 3. Discussion Case #3


1)How is this case similar or different from:
a)a case where the findings would have revealed a positive antinuclear antibody?
b)a case where the findings would have revealed a positive antistreptolysin O antibody with high titer?
2)Would you want to take a biopsy of this girl’s kidney? Why or why not?
3)How does the lack of complement components contribute to this disease?

Idiopathic membrane proliferative glomerulonephritis is an inherited deficiency of complement components. This girl could be C2 minus and cannot clear immune complexes. This would be most common. Complement would be absent under these conditions. She could also be C4 minus- there are two allotypes that make different proteins. If deficient in one, then there would be immune complex disease and hypocomplementia. This is probably what this girl has.