Mnemonics for Medicine: Differential Diagnoses and Other Pearls

By Robert M Gullberg MD

Mnemonics are extremely useful in learning the details of medicine, especially when there are "lists of key causes" to remember. These lists are often on written and clinical exams and medical board tests (such as National Boards and PANCE, Nursing Boards), so it is incumbent on the student to know them well. After a while, the use of mnemonics will become easy.

This book contains over 200 "easy to recall" mnemonics and other pearls that will aid the student in grasping important lists of differential diagnoses concerning common medical problems. I have chosen the most common internal medicine problems in 13 main categories.

The sheer volume of facts to learn and memorize in the study of Medicine can be daunting. Double boarded in both Internal Medicine and Infectious Diseases, I have been teaching clinical adult medicine to students for over 30 years (Medical, Physician Assistant, and Nursing) and it is not unusual for us to deal with 25 different diagnoses while on daily hospital rounds. I teach the students the importance of having a "differential diagnosis" of a medical problem at their fingertips.

Each mnemonic has an associated picture which will help you to visually engrain it in your mind. A keypoint is included with the mnemonic for 'KEY POINT' emphasis.

I have included my "Triples, Tetrads, and Pentads" and other charts to help you review the numerous 'pearls of medicine'.

-Robert M. Gullberg, M.D., F.A.C.P.

• Language: English
• Publisher: BookBaby
• Release date: Nov 30, 2020
• ISBN: 9781953131058

Book preview

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Anaphylactic Shock Treatment

A teenager presents with increasing SOB, wheezing, delirium, cyanosis, a swollen tongue, and a blood pressure of 75/50. You diagnose anaphylactic shock. IV fluids are ordered stat.

Treatment: Mnemonic: P H O N E S

P-Pulmonary treatments. Stat. Use Albuterol- 0.5 ml in 2.5 ml saline q 3 hours; small volume nebulizer. H-Histamine blockers. Benadryl 25 mg IV stat, then Q 6 hours or cetirizine 10 mg BID with Cimetidine, 300 mg IV q 8 hour. O-Oxygen. Keep pulse oximetry >90%. Respiratory Therapy to assess and rx. N-Norepinephrine (Levophed). 8-12 mcg/min IV. E-Epinephrine. Acute bronchodilator. 1/1000 strength. Use 0.5 ml IM q 10 minutes or 1-4 mcg/min IV. S- Solumedrol (methylprednisolone). 250 mg IV STAT, then 125 mg q 6 hours.

KEY POINT: Remember for future avoidance you must find the triggers of the anaphylaxis- this is often obvious, but sometimes allergy consult is needed. Be sure to prescribe an Epi-pen for future use.

Common Causes of Anaphylaxis

A patient presents with a history of recurrent hives, recurrent tongue swelling, and wheezing. You investigate the cause of her severe allergy.

Causes: Mnemonic: S I M N E L

S-Shellfish and other finned fish. I-Insect bites and stings. M-Medications. Especially antibiotics, ASA, NSAIDS, ACE inhibitors and IV contrast. N-Nuts. Especially tree nuts and peanuts. E-Eggs. Also: other dairy such as milk. L-Latex rubber. A common problem in the healthcare field.

KEY POINT: Bees (honeybees, hornets, yellow jackets), wasps, and fire ants are common causes.

Hypersensitivity Reactions

A patient presents with anaphylaxis from eight wasp stings. What kind of hypersensitivity reaction is this? Type 1. What are the other three?

Four types of hypersensitivity: Mnemonic: A C I D

A-Anaphylaxis. Type 1- allergic, atopy. Mediated by IgE, IgG4. C-Cytotoxic. Type 2- antibody dependent -Grave’s, Hem. Anemia. Goodpasture’s, Myasthenia gravis. Mediated by IgM or IgG and complement. I-Immune. Type 3- IgG-IgM complexes and complement- serum sickness, Arthus reaction, SLE, RA, Stevens-Johnson Syndrome, hypersensitivity pneumonitis. D-Delayed. Type 4- delayed hypersensitivity, cell-mediated immunity. Contact dermatitis, MS, transplant rejection. Mediated by T-cells.

KEY POINT: Hypersensitivity reactions cause a wide variety of symptoms and physical findings.

Types of Allergens

A patient presents with an eczematoid skin rash, itchy, watery eyes, and asthma. You think of allergies.

Causes of allergies: Mnemonic: M A D F L I P

M-Mold spores. Airborne basidiospores such as mushrooms, rusts, puffballs, aspergillus. Metal- nickel. A-Animal products. Fel d-1 protein in cat saliva, dog/cat dander, cockroach, dust mite excreta, sheep, wool. D-Drugs. Penicillin, salicylates, sulfa. // F-Foods. Celery, corn, egg whites, pumpkin, legumes- peanuts (peas, soybeans) milk, seafood, sesame, tree nuts-pecans/almonds, wheat, banana, pineapple, avocado, kiwi, strawberry, shellfish-shrimp, oysters. L-Latex. Type 1 anaphylaxis and Type 4 allergic dermatitis. Watch for in healthcare settings. I-Insect stings. Bee/wasp venom, mosquito bites. P-Plant pollen. Rye grass, weeds such as ragweed, trees like birch, willow, poplar, pine.

KEY POINT: Use oral steroids, and antihistamines like cetirizine and H1 antagonists in treatment.

Mast Cell Disease

A patient presents with increasing flushing, itching, runny nose, tearing eyes, bronchospasm, and abdominal pain with bloating, N/V and diarrhea. You think of Mast Cell Disease (Mastocytosis).

Mnemonic: M A T H

M-Mast cells are the master regulators of the immune system. They contain basophilic granules that release histamine and other chemicals. They are overproduced in this disease to produce flushing, itch, hives, headache, and low BP. A-Abdominal pain. And other GI symptoms are common such as bloating and diarrhea. T-Tryptase levels. Elevated in this disease. Also 24-N-methylhistamine levels are high. H-H1 and H2 antagonists for Rx. Also mast cell stabilizers such as cromolyn Na.

KEY POINT: No good treatment. Over-abundance of mast cells in peripheral blood and bone marrow. Can become cancerous with the deposit of mast cells in organs. Associated with leukemia and sarcoma. Associated with KIT gene mutation. Activators include opioids, antibiotics, NSAIDs, and ETOH.

Allergic Rhinitis

A 21 y/o patient presents with increase in nasal stuffiness, lacrimation, itchy throat, wheezing and sneezing. There is a history of eczema and asthma.

Mnemonic: S A I L O R

S-Sneezing. Prominent symptom of allergic rhinitis. A-Atopic individuals. Common in patients with eczema, hives, or asthma. I-Itch. Known as pruritis. Common of the eyes, nose, throat. L-Lacrimation. Frequently patients with AR have increase in tearing. O-Obstruction of nasal passages. Very stuffy is the rule. R-Rhinorrhea. Nose runs like a faucet is common. Must find allergy trigger.

KEY POINT: AR patients frequently have eosinophilia. Treatment is topical steroid sprays (like Flonase or Nasonex), or Ipratropium. Consider decongestants, oral antihistamines such as cetirizine or Xyzal. Oral prednisone may be needed for short term treatment.

Acute MI 14 Day Mortality Rate

A patient with history of angina presents with an acute MI. You want to calculate the mortality rate. Check the TIMI trial. Thrombolysis In Myocardial Infarction.

Mnemonic: A M E R I C A (each letter gets 1 point)

A->65 y/o. M- Markers. Increased (CPK, trop). E- EKG. ST segment changes R- Risk factors. 3 or more risk factors- age, family history, diabetes, high cholesterol, HTN, smoking, obesity, sedentary lifestyle, metabolic syndrome. I-Ischemia. 2 or more anginal events in last 24 hours C- CAD- prior 50% coronary stenosis. A-Aspirin use in last week.

KEYPOINT: Point Score for mortality rate- 0-1- 4.7%, 2- 8.3%, 3- 13.2%, 4- 19.9%, 5-26.2%, 6-7- 40.9%.

Aortic Stenosis

A patient presents with a new Grade 3/6 systolic heart murmur right second ICS and syncope. You suspect aortic stenosis.

Mnemonic: C A B S

C-Congestive Heart Failure. One aspect of the clinical triad along with syncope and angina/LVH. A-Aortic sclerosis. Common cause in the elderly. (Calcium build-up in the valve). Also: A-Angina. One of the triads along with syncope and CHF. B-Bifid aortic valve. Common cause of aortic stenosis. Seen in 1/300 of the general population. Normal valve is trifid. S-Syncope. One aspect of the triad of CHF, angina and syncope seen with severe AS.

KEYPOINT: The aortic valve area is normally 1.5-2 square cms. Severe AS valve area decreases to 0.8 square cms. AS is seen in 25% of the elderly population. TAVR procedure popular to fix AS.

Atrial fibrillation

A patient presents new onset SOB with an elevated, irregular pulse of 120. EKG reveals Atrial Fibrillation.

Mnemonic: R E A C H

R-Rate Control. Goal resting pulse < 100. Use metoprolol (tartrate is short acting; succinate is long acting) or diltiazem. Rhythm control- amiodarone, Multaq (dronedarone), Tikosyn (dofetilide), or ablation. E-Eight %. 8% over age 80 has AF. Common cause of morbidity in the elderly. A-Anticoagulation. CHADS2-VASC score for risk of stroke. Warfarin, Eliquis, Xarelto used; 98.7% reduction of CVA. Alcohol- over consumption is common cause of AF. C-Coronary artery disease. A common cause of atrial fibrillation; also left atrial stretch, along with COPD. H-Hypertension. Common cause of AF, as well as hyperthyroidism.

KEYPOINT: Atrial fibrillation is common cause of acute embolic stroke. Many people who have TIAs have paroxysmal atrial fibrillation only found with a implanted loop recorder.

Cardiomyopathy

A patient presents with SOB and a cardiomyopathy on Echocardiogram. EF on ECHO is 26%.

Causes: Mnemonic: I N T E R I M

I-Ischemic. Most common. Also: Infectious causes- Chagas (Trypanosomiasis), viral such as Coxsackie. Flu, HIV. N-Neuromuscular. Muscular dystrophy, Mitochondrial myopathy. T-Toxins. Chronic ETOH abuse, chemotherapy (Adriamycin) E-Eosinophilic. Loeffler’s Syndrome. Also: Endocrine- DM, hyperthyroid, acromegaly. R-Restrictive- Hemochromatosis, Sarcoidosis I- IHSS. Idiopathic hypertrophic subaortic stenosis, or ASH (asymmetric septal hypertrophy). M-Metabolic. Amyloidosis, obesity.

KEYPOINT: No matter the cause, once the EF drops to less than 35%, there is increased risk of death and an AICD (automatic implantable cardioverter-defibrillator) may be indicated.

Chest Pain

A patient presents with chest pain of unknown etiology. BP is elevated and they are SOB.

Causes: Mnemonic: C A P E

C-Costal Chondritis. Musculoskeletal. Common in patients with fibromyalgia, trauma. A-Angina pectoris, MI. Also: Aortic dissection. P-Pulmonary embolus/infarction. Also: Pericardial disease, Pleuritis/Pleurisy- inflammation of pleura-seen in infections like Coxsackie, also Prolapse of the mitral valve. E-Esophageal spasm. From esophagitis, GERD, dysphagia, or presbyesophagus.

KEYPOINT: W/U- press against chest for reproducible pain,1 oz. Maalox, SL Nitroglycerin, EKG, Troponin, D-dimer, chest x-ray (or CT is best for dissection), ECHO to check for MVP.

Diastolic Dysfunction

A patient presents signs of congestive heart failure-SOB, orthopnea, and PND. However, ECHO shows a normal EF of 55%, and you suspect diastolic dysfunction.

Mnemonic: D E C I L E

D-Decrease in cardiac compliance. E-End Diastolic Pressure elevation. C- Congestive Heart Failure symptoms. SOB, fatigue, PND, orthopnea. BNP is elevated >200. I-Increase in Blood Pressure. Chronic HTN is the most common cause. L-Left ventricular stiffness. Stiff left ventricle leads to elevation of the atrial kick wave. E- End Diastolic wave < Atrial Kick wave. Normally, the End Diastolic wave>Atrial Kick wave. Opposite