Disease Summaries for Medical Students: A Simple Structure and Approach.
Introduction
Pathophysiology is a full-on and heavy subject to learn in medical school, and with so much going on during the clinical years, it is essential to create a streamlined and efficient way to describe diseases/conditions. By the end of the year, you may have a long list of diseases to learn and remember: hence, I recommend keeping it brief, succinct and easy to explain.
There are numerous ways to create a disease summary. I recommend keeping the diseases in systems making it a lot easier to remember and use plenty of creativity. I had many creative colleagues, each with different learning styles, making interesting disease summaries such as the example below. If possible, use mnemonics (such as the 6 Fs of cholesterol gallstones) and lots of drawings to keep it fun and easy to remember. Whatever your style is, it needs to make sense to you for your understanding.
Remember to use KISS: Keep It Simple, Stupid or Keep It Super Simple.
Image from: K Popham. Flourish Notepads: Disease Summary. Instagram website: https://www.instagram.com/flourish_notepads/.
Disease summary structure
Below is the backbone structure to make notes on a particular disease. It is bland but essentially it is the basics, thus try to add in each headline. Some diseases might not even fill all the headlines, which is fine. After getting the hang of it, use colours, flowcharts, cycles, tables, memes/cartoons, et cetera. As an example, I shall use acute rheumatic fever (ARF), focusing on patients living in Australia as that is where we were taught and most likely will see patients with ARF. Keep it relevant to your clinical settings.
Disease/condition: title of your disease/condition of study.
Definition: in a short sentence, describe the condition. Do add the most crucial information, but keep it simple.
Epidemiology & aetiology: you can break this down into three different headlines -> epidemiology (who gets it, how often and where), aetiology (what is the causative agent, how did it start), and risk factors.
Causes: what is the cause of the disease/condition? Sometimes it can be complex and not as straightforward, so keep it succinct.
Pathophysiology: write the pathogenesis in a compelling description that makes sense and is easily explained.
Pathology (gross and microscopy): describe what you would see grossly, meaning the tissue without a microscope, and then microscopically whilst analysing the cells present. I recommend using photos of real specimens and slides.
Presentation: incorporate physical examination findings and focussed history. Highlight what to look (signs) for and what to ask (symptoms).
Differentials: list your top diagnosis and three differentials.
Investigations: what is needed to rule in or rule out. Includes: bedside, bloods, imaging and special tests.
Scoring system: if available, use criteria that help in ruling-in/out.
Management and treatment: may include (be brief):
Emergency intervention,
Non-pharmacology/conservative,
Lifestyle changes,
Pharmacology,
Follow-ups,
Referral with who and,
Medical/surgical intervention.
Complications and prognosis: what are the immediate, long term and life-threatening complications?
Prevention: what can be done to prevent this disease/condition? Think about your primordial, primary, secondary, tertiary and quaternary prevention. This proves to be challenging in certain conditions, and some won’t have all of the prevention levels.
References: keeping references is helpful in quickly going back for fact-checking or looking for more details and information. Stay on trusted and reliable websites.
Disease/Condition
Acute rheumatic fever (ARF).
Definition
Multisystem autoimmune disease affecting the heart, joints, skin and brain following an autoimmune response to group A streptococcus infection.
Epidemiology & aetiology
Epidemiology
Predominantly affects Aboriginal and Torres Strait Islander children aged 5-14 years living in regional and remote areas of central and north Australia.
Incidence: 250-350 per 100 000 in Aboriginal and Torres Strait Islander population.
Rare in the Western world.
ARF is more common in females than males.
Aetiology (ARF is an autoimmune disease, thus always includes genetic susceptibility, environmental factors, and autoimmunity)
Genetic susceptibility: there is some genetic susceptibility, but it is relatively weak.
Environmental factors: overcrowding and hygiene.
Autoimmunity: T cell, anti-DNAse B and autoantibodies.
Risk factors
Being exposed to group A streptococcus (GAS).
Overcrowding and poor hygiene.
Poor dental care.
Nutrition, IV drug usage.
Causes
ARF, for example, the primary causative agent is GAS but is integrated with genetics, environment and autoimmunity. It is a good idea to get its microbiology information such as shape (cocci/rod), gram +/- and so on.
Pathophysiology
Repeat infection with GAS -> produces hypersensitivity reaction (1-3 weeks after exposure) -> antibodies against GAS cross-react with myocardial (M proteins) and valvular proteins (molecular mimicry) -> CD4+ T cells cross react and cytokine mediated inflammatory response (acute) then to scarring (chronic) -> repeated ARF episodes = recurrent endocarditis and permanent valve damage-> rheumatic heart disease (RHD).
Pathology (gross and microscopy)
Gross: endocarditis damage, fibrinous pericarditis (bread and butter looking). In RHD, the gross specimen is evident when looking at a heart valve, leaflets, chordae tendineae and papillary muscles.
Microscope: Aschoff bodies + Anitschkow cells in the myocardium, central fibrinoid necrosis, T-lymphocytes and plasma cells are all present.
Presentation
Focussed history
Have you recently had a sore throat or rash or nodules?
Have you ever been diagnosed with rheumatic fever?
Do you become breathless during exertion?
Does anyone in your family have to have medicine every month?
Has a doctor ever told you that you have a heart problem?
Have you ever had to take medication before working on your teeth?
Examination findings
General and vitals: fever, arrhythmia (AF), JONES criteria, mitral facies (CO2 is vasodilatory), worsening SOB (due to cardiac involvement).
Cardiovascular examination:
Weak heart sounds: reduced heart function.
Mitral stenosis = opening snap, mid-diastolic murmur, tapping apex beat, loud S1, parasternal heave.
Mitral regurgitation = pansystolic murmur, radiates to axillae.
Aortic stenosis = midsystolic ejection murmur, loud at the aorta, radiates to carotids.
May also hear a pericardial rub in ARF (pericarditis does not present chronically).
Dyskinetic apex beat, S3 and bibasilar crackles: if heart failure is present (dyskinetic = larger apex beat, uncoordinated).
AF: HR may be fast and irregular, pulse deficit may be present (in AF, ventricular contraction may not produce a palpable pulse with each contraction).
Respiratory examination:
Basilar crackles: due to pulmonary oedema. May also cause white sputum on a cough.
Skin and neurology examination will be relevant for JONES criteria.
Differentials
Most likely: acute rheumatic fever.
Differentials: infective endocarditis, reactive/septic or rheumatoid arthritis, SLE, tinea corporis (for erythema marginatum), et cetera.
Investigations
Evidence of GAS infection: throat swab culture, rapid strep Ag test, high strep Ab titre (ASO or DNase B).
Electrocardiogram: right ventricular hypertrophy -> tall R waves in V1-3, possible in AF.
ESR/CRP level.
Chest X-Ray: enlarged LA and appendage (double density sign).
Cardiomegaly due to pancarditis.
Bilateral, diffuse ‘fluffy’ opacification (APO).
Echocardiogram: thickened, immobile cusps.
FBC – leucocytosis.
Scoring system
JONES criteria.
Management & treatment
Antibiotics: single-dose benzylpenicillin IM or phenoxymethylpenicillin PO to eliminate strep (erythromycin or a cephalosporin if allergic) for ten days.
Bed rest until CRP normal: to lessen cardiac workload and arthritic pain.
Arthritis and fever: paracetamol or codeine if unconfirmed diagnosis. Confirmed, severe arthritis: analgesics such as aspirin or steroids, and immobilise the joints.
Sydenham’s chorea: carbamazepine/haloperidol. No treatment in most cases.
Congestive heart failure: urgent echo, diuretics/fluid restriction, ACE inhibitors.
Atrial fibrillation: digoxin, beta-blockers or electrical cardioversion.
Secondary prophylaxis: benzathine penicillin IM monthly or oral phenoxymethylpenicillin BD if non-compliant. Sulfadiazine or erythromycin if penicillin-allergic. Give for ten years or until 21 (whichever is longer).
Other: access to oral healthcare services. Access to specialist physicians such as paediatricians and cardiologists.
Complications and prognosis
Rheumatic heart disease is the most crucial disease to prevent as a complication from reoccurring ARF as it causes severe disabilities, resulting in death. Untreated ARF drastically increases a person’s risk of recurrent attacks and worsens prognosis. The prognosis of ARF corresponds to the recurrent episodes, degree of cardiac valvular damage, and degree of overall cardiac involvement. These cardiac complications can vary in severity and often includes pericarditis, endocarditis, arrhythmias, valvular damage, and congestive heart failure.
Prevention
In ARF, you have:
Primordial (prevent from the causative agent): improve the social-economic status, education and awareness, improve crowding and access to health, discuss hygiene, have adequate water and sewer systems. Employ Aboriginal and Torres Strait Islander Health Workers in closing the gaps.
Primary (prevent from acquiring the disease): antibiotics to treat a strep A infection before ARF develops.
Secondary (prevent from acquiring complications): regular secondary (antibiotic) prophylaxis is recommended for people diagnosed with ARF and RHD.
Tertiary (prevent death and improve quality of life): slow the progression of RHD by preventing and managing complications to maintain quality of life and prevent premature death.
Quaternary: aim to prevent over medicalisation and polypharmacy. Keep up to date with the general practitioner monitoring as well as keeping up with the specialists. Use the allied health workers (dietician, district nurse, pharmacists, et cetera) accordingly.
References
Centers for Disease Control and Prevention Acute Rheumatic Fever
The Royal Australian College of General Practitioners Acute Rheumatic Fever
Final say
A disease summary can be tedious and may take much time, but keep going at it whenever you learn a new topic. Pay more attention to the major/significant and most common disorders, and don’t spend too much time on the rare ones. Just be brief about the rare diseases and write a few lines. Make friends and work collaboratively if you can, as it will speed the process and use plenty of creativity! Otherwise, it will be a painful experience to learn such a vast amount of knowledge for your examinations. It is pretty rewarding to look back on your work proudly with appreciation, and who knows, one day you could pass it down.
Published 15th September 2021. Last reviewed 5th January 2022.
Reference
Aqua Asif. Medical Students – Transitioning Tips into Clinical Years. Learn Surgery Online website. https://www.learnsurgeryonline.com/medical-students-transitioning-tips-into-clinical-years/. Published May 16, 2020. Accessed April 29, 2021.
Australian Family Physician authors. Rheumatic fever Identification, management and secondary prevention. The Royal Australian College of General Practitioners website. https://www.racgp.org.au/afp/2012/january-february/rheumatic-fever. Published January-February, 2012. Accessed January 7, 2022.
CDC author. Acute Rheumatic Fever. CDC website .https://www.cdc.gov/groupastrep/diseases-hcp/acute-rheumatic-fever.html. Reviewed July 12, 2018. Accessed January 7, 2022.
K Popham. Flourish notepads. Instagram website. https://www.instagram.com/flourish_notepads/. Accessed January 7, 2022.
Sara Noonan. Prevention of ARF and RHD - in detail. RHD Australia website. https://www.rhdaustralia.org.au/prevention-arf-and-rhd-detail. Updated October 27, 2020. Accessed January 7, 2022.
Sara Noonan. What is acute rheumatic fever? RHD Australia website. https://www.rhdaustralia.org.au/what-acute-rheumatic-fever. Updated October 27, 2020. Accessed January 7, 2022.
WHO authors. Rheumatic Heart Disease. World Health Organization website. https://www.who.int/news-room/fact-sheets/detail/rheumatic-heart-disease. Updated November 6, 2020. Accessed January 7, 2022.