Skip to Main Content

How to Approach Clinical Problems

++

  • Part 1 Approach to the Patient

  • Part 2 Approach to Clinical Problem Solving

  • Part 3 Approach to Reading

++

Part 1. Approach to the Patient

++

The transition from the textbook or journal article to the clinical situation is one of the most challenging tasks in medicine. Retention of information is difficult; organization of the facts and recall of a myriad of data in precise application to the patient is crucial. The purpose of this text is to facilitate in this process. The first step is gathering information, also known as establishing the database. This includes taking the history (asking questions), performing the physical examination, and obtaining selective laboratory and/or imaging tests. Of these, the historical examination is the most important and useful. Sensitivity and respect should always be exercised during the interview of patients.

++

CLINICAL PEARL

  • The history is the single most important tool in obtaining a diagnosis. History-taking for the older patient is more challenging because of complexity of the medical or therapeutic problems, and possible cognition or hearing issues. Patience and a caring attitude are paramount.

++

History

++

  1. Basic information: Age, gender, ethnicity, and reliability must be recorded because some conditions are more common in various ethnicities. Reliability may be questionable; for instance, a patient may not want to appear to not recall what medications or what surgeries s/he has had and volunteer various facts in an assured fashion. These findings should be gently and discretely verified.

  2. Chief complaint: What is it that brought the patient into the hospital or clinic? Is it a scheduled appointment, or an unexpected symptom? The patient's own words should be used if possible, such as, “I feel like a ton of bricks are on my chest.” The chief complaint, or real reason for seeking medical attention, may not be the first subject the patient talks about (in fact, it may be the last thing), particularly if the subject is embarrassing, such as a urinary incontinence, or highly emotional, such as elder abuse. It is often useful to clarify exactly what the patient's concern is; for example, they may fear their headaches represent an underlying brain tumor.

  3. History of present illness: This is the most crucial part of the entire database. The questions one asks are guided by the differential diagnosis one begins to consider the moment the patient identifies the chief complaint, as well as the clinician's knowledge of typical disease patterns and their natural history. The duration and character of the primary complaint, associated symptoms, and exacerbating/relieving factors should be recorded. Sometimes, the history will be convoluted and lengthy, with multiple diagnostic or therapeutic interventions at different locations. For patients with chronic illnesses, obtaining prior medical records is invaluable. For example, when extensive evaluation of a complicated medical problem has been done elsewhere, it is usually better to first obtain those results than to repeat a “million-dollar workup.” When reviewing prior records, it is often useful to review the primary data (eg, biopsy reports, echocardiograms, serologic evaluations) rather than to rely upon a diagnostic label applied by someone else, which then gets replicated in medical records and by repetition acquires the aura of truth, when it may not be fully supported by data. Many older patients will be poor historians because of dementia, confusion, or language barriers; recognition of these situations and querying of family members is useful. Yet, sensitivity and allowing the patient to retain their self-respect and dignity are important. When little or no history is available to guide a focused investigation, more extensive objective studies are often necessary to exclude potentially serious diagnoses.

  4. Past medical history:

    1. Illness: Any illnesses such as hypertension, hepatitis, diabetes mellitus, cancer, heart disease, pulmonary disease, and thyroid disease should be elicited. If an existing or prior diagnosis is not obvious, it is useful to ask exactly how it was diagnosed; that is, what investigations were performed. Duration, severity, and therapies should be included.

    2. Hospitalization: Any hospitalizations and emergency room (ER) visits should be listed with the reason(s) for admission, the intervention, and the location of the hospital.

    3. Blood transfusion: Transfusions with any blood products should be listed, including any adverse reactions.

    4. Surgeries: The year and type of surgery should be elucidated and any complications documented. The type of incision and any untoward effects of the anesthesia or the surgery should be noted.

  5. Allergies: Reactions to medications should be recorded, including severity and temporal relationship to the medication. An adverse effect (such as nausea) should be differentiated from a true allergic reaction.

  6. Medications: Current and previous medications should be listed, including dosage, route, frequency, and duration of use. Prescription, over-the-counter, and herbal medications are all relevant. Patients often forget their complete medication list; thus, asking each patient to bring in all their medications—both prescribed and nonprescribed—allows for a complete inventory.

  7. Family history: Many conditions are inherited, or are predisposed in family members. The age and health of siblings, parents, grandparents, and others can provide diagnostic clues. For instance, an individual with first-degree family members with early onset coronary heart disease is at risk for cardiovascular disease.

  8. Social history: This is one of the most important parts of the history which includes the patient's functional status at home, social and economic circumstances, and goals and aspirations for the future. These are often critical in determining the best way to manage a patient's medical problem. Living arrangements, economic situations, and religious affiliations may provide important clues for puzzling diagnostic cases, or suggest the acceptability of various diagnostic or therapeutic options. Marital status and habits such as alcohol, tobacco, or illicit drug use may be relevant as risk factors for disease. A patient's sexual history should be asked in a nonthreatening manner.

  9. Activity level: An older patient's level of activity and functioning is important to document in a systematic and accurate manner. Activities of daily living and being able to care for self are critical areas to record.

  10. Review of systems: A few questions about each major body system ensure that problems will not be overlooked. The clinician should avoid the mechanical “rapid-fire” questioning technique that discourages patients from answering truthfully because of fear of “annoying the doctor.”

++

Physical Examination

++

The physical examination begins as one is taking the history, by observing the patient and beginning to consider a differential diagnosis. When performing the physical examination, one focuses on body systems suggested by the differential diagnosis, and performs tests or maneuvers with specific questions in mind; for example, does the patient with jaundice have ascites? When the physical examination is performed with potential diagnoses and expected physical findings in mind (“one sees what one looks for”), the utility of the examination in adding to diagnostic yield is greatly increased, as opposed to an unfocused “head-to-toe” physical.

++

  1. General appearance: A great deal of information is gathered by observation, as one notes the patient's body habitus, state of grooming, nutritional status, level of anxiety (or perhaps inappropriate indifference), degree of pain or comfort, mental status, speech patterns, and use of language. Bruising that may indicate physical abuse, or withdrawn affect that may indicate depression or abuse are important to elicit. This forms your impression of “who this patient is.”

  2. Vital signs: Vital signs such as temperature, blood pressure, heart rate, respiratory rate, height, and weight are often placed here. Blood pressure can sometimes be different in the 2 arms; initially, it should be measured in both arms. In patients with suspected hypovolemia, pulse and blood pressure should be taken in supine and standing positions to look for orthostatic hypotension. It is quite useful to take the vital signs oneself, rather than relying upon numbers gathered by ancillary personnel using automated equipment, because important decisions regarding patient care are often made using the vital signs as an important determining factor.

  3. Head and neck examination: Facial or periorbital edema and pupillary responses should be noted. Inspection for cataracts should be performed. Funduscopic examination provides a way to visualize the effects of diseases such as diabetes on the microvasculature; papilledema can signify increased intracranial pressure. Estimation of jugular venous pressure is very useful to estimate volume status. The thyroid should be palpated for a goiter or nodule, and carotid arteries auscultated for bruits. Cervical (common) and supraclavicular (pathologic) nodes should be palpated.

  4. Breast examination: Inspect for symmetry, skin or nipple retraction with the patient's hands on her hips (to accentuate the pectoral muscles) and also with arms raised. With the patient sitting and supine, the breasts should then be palpated systematically to assess for masses. The nipple should be assessed for discharge and the axillary and supraclavicular regions should be examined for adenopathy.

  5. Cardiac examination: The point of maximal impulse (PMI) should be ascertained for size and location, and the heart auscultated at the apex as well as at the base. Heart sounds, murmurs, and clicks should be characterized. Murmurs should be classified according to intensity, duration, timing in the cardiac cycle, and changes with various maneuvers. Systolic murmurs are very common and often physiologic; diastolic murmurs are uncommon and usually pathologic.

  6. Pulmonary examination: The lung fields should be examined systematically and thoroughly. Wheezes, rales, rhonchi, and bronchial breath sounds should be recorded. Percussion of the lung fields may be helpful in identifying the hyperresonance of tension pneumothorax, or the dullness of consolidated pneumonia or a pleural effusion.

  7. Abdominal examination: The abdomen should be inspected for scars, distension, or discoloration (such as the Grey Turner sign of discoloration at the flank areas indicating intra-abdominal or retroperitoneal hemorrhage). Auscultation of bowel sounds to identify normal versus high-pitched and hyperactive versus hypoactive is required. Percussion of the abdomen can be used to assess the size of the liver and spleen, and to detect ascites by noting shifting dullness. Careful palpation should begin initially away from the area of pain, involving one hand on top of the other, to assess for masses, tenderness, and peritoneal signs. Tenderness should be recorded on a scale (eg, 1 to 4 where 4 is the most severe pain). Aortic aneurysms should be assessed. Guarding, whether voluntary or involuntary, should be noted.

  8. Back and spine examination: The back should be assessed for symmetry, tenderness, and masses. Compression fractures may lead to a hunched appearance. The flank regions are particularly important to assess for pain on percussion, which might indicate renal disease.

  9. Genitalia:

    1. Females: The pelvic examination should include an inspection of the external genitalia, and with the speculum, evaluation of the vagina and cervix. A pap smear and/or cervical cultures may be obtained if relevant, although these are rarely needed after age 65 to 70 years unless a prior cervical dysplasia history is present. A bimanual examination to assess the size, shape, and tenderness of the uterus and adnexa is important.

    2. Males: An inspection of the penis and testes is performed. Evaluation for masses, tenderness, and lesions is important. Palpation for hernias in the inguinal region with the patient coughing to increase intra-abdominal pressure is useful.

  10. Rectal examination: A digital rectal examination is generally performed for individuals with possible colorectal disease or gastrointestinal bleeding. Masses should be assessed. In men, the prostate gland can be assessed for enlargement and for nodules.

  11. Extremities: An examination for joint effusions, tenderness, edema, and cyanosis may be helpful. Clubbing of the nails might indicate pulmonary diseases such as lung cancer or chronic cyanotic heart disease.

  12. Neurological examination: A routine mental status examination and gait examination should be performed on every old patient. Patients who present with neurological complaints usually require a thorough assessment, including the mental status, cranial nerves, motor strength, sensation, and reflexes.

  13. Skin examination: The skin should be carefully examined for evidence of pigmented lesions (melanoma), cyanosis, or rashes that may indicate systemic disease (malar rash of systemic lupus erythematosus).

++

Laboratory and Imaging Assessment

++

  1. Laboratory:

    1. Complete blood count: CBC (complete blood count) to assess for anemia and thrombocytopenia.

    2. Evaluation: Chemistry panel is most commonly used to evaluate renal and liver function.

    3. Lipid panel: Lipid panel is particularly relevant in cardiovascular diseases.

    4. Urinalysis: Urinalysis is often referred to as a “liquid renal biopsy,” because the presence of cells, casts, protein, or bacteria provides clues about underlying glomerular or tubular diseases.

    5. Infection: Gram stain and culture of urine, sputum, and cerebrospinal fluid, as well as blood cultures, are frequently useful to isolate the cause of infection.

  2. Imaging procedures:

    1. Chest radiography: Chest radiography is extremely useful in assessing cardiac size and contour, chamber enlargement, pulmonary vasculature and infiltrates, and the presence of pleural effusions.

    2. Ultrasonographic examination: Ultrasonographic examination is useful for identifying fluid–solid interfaces and for characterizing masses as cystic, solid, or complex. It is also very helpful in evaluating the biliary tree, kidney size, and evidence of ureteral obstruction, aortic aneurysms, and can be combined with Doppler flow to identify deep venous thrombosis. Ultrasonography is noninvasive and has no radiation risk, but cannot be used to penetrate through bone or air, and is less useful in obese patients.

      CLINICAL PEARL

      • Ultrasonography is helpful in evaluating the biliary tree, looking for ureteral obstruction, and evaluating vascular structures, but has limited utility in obese patients.

    3. Computed tomography: Computed tomography (CT) is helpful in possible intracranial bleeding, abdominal and/or pelvic masses, and pulmonary processes, and may help delineate the lymph nodes and retroperitoneal disorders. CT exposes the patient to radiation and requires the patient to be immobilized during the procedure. Generally, CT requires administration of a radiocontrast dye, which can be nephrotoxic and older individuals often have a degree of renal insufficiency.

    4. Magnetic resonance imaging: Magnetic resonance imaging (MRI) identifies soft-tissue planes very well and provides the best imaging of the brain parenchyma. When used with gadolinium contrast (which is not nephrotoxic), MR angiography (MRA) is useful for delineating vascular structures. MRI does not use radiation, but the powerful magnetic field prohibits its use in patients with ferromagnetic metal in their bodies, for example, many prosthetic devices.

    5. Cardiac procedures:

      • (i) Echocardiography: Uses ultrasonography to delineate the cardiac size, function, ejection fraction, and presence of valvular dysfunction.

      • (ii) Angiography: Radiopaque dye is injected into various vessels and radiographs or fluoroscopic images are used to determine the vascular occlusion, cardiac function, or valvular integrity.

      • (iii) Stress treadmill tests: Individuals at risk for coronary heart disease are monitored for blood pressure, heart rate, chest pain, and electrocardiogram (ECG) while increasing oxygen demands on the heart, such as running on a treadmill. Nuclear medicine imaging of the heart can be added to increase the sensitivity and specificity of the test. Individuals who cannot run on the treadmill (such as those with severe arthritis), may be given medications such as adenosine or dobutamine to “stress” the heart.

++

Part 2. Approach to Clinical Problem Solving

++

There are typically 4 distinct steps to the systematic solving of clinical problems:

++

  1. Making the diagnosis

  2. Assessing the severity of the disease (stage)

  3. Rendering a treatment based on the stage of the disease

  4. Following the patient's response to the treatment

++

Making the Diagnosis

++

There are 2 ways for making a diagnosis. Experienced clinicians often make a diagnosis very quickly using pattern recognition, that is, the features of the patient's illness match a scenario the physician has seen before. If it does not fit a readily recognized pattern, then one has to undertake several steps in diagnostic reasoning:

++

  1. The first step is to gather information with a differential diagnosis in mind. The clinician should start considering diagnostic possibilities with initial contact with the patient, which is continually refined as information is gathered. Historical questions and physical examination tests and findings are all pursued tailored to the potential diagnoses one is considering. This is the principle that “you find what you are looking for.” When one is trying to perform a thorough head-to-toe examination, for instance, without looking for anything in particular, one is much more likely to miss findings.

  2. The next step is to try to move from subjective complaints or nonspecific symptoms to focus on objective abnormalities in an effort to conceptualize the patient's objective problem with the greatest specificity one can achieve. For example, a patient may come to the physician complaining of pedal edema, a relatively common and nonspecific finding. Laboratory testing may reveal that the patient has renal failure, a more specific cause of the many causes of edema. Examination of the urine may then reveal red blood cell casts, indicating glomerulonephritis, which is even more specific as the cause of the renal failure. The patient's problem, then, described with the greatest degree of specificity, is glomerulonephritis. The clinician's task at this point is to consider the differential diagnosis of glomerulonephritis rather than that of pedal edema.

  3. The last step is to look for discriminating features of the patient's illness. This means the features of the illness, which by their presence or their absence narrow the differential diagnosis. This is often difficult for junior learners because it requires a well-developed knowledge base of the typical features of disease, so the diagnostician can judge how much weight to assign to the various clinical clues present. For example, in the diagnosis of a patient with a fever and productive cough, the finding by chest x-ray of bilateral apical infiltrates with cavitation is highly discriminatory. There are few illnesses besides tuberculosis that are likely to produce that radiographic pattern. A negatively predictive example is a patient with exudative pharyngitis who also has rhinorrhea and cough. The presence of these features makes the diagnosis of streptococcal infection unlikely as the cause of the pharyngitis. Once the differential diagnosis has been constructed, the clinician uses the presence of discriminating features, knowledge of patient risk factors, and the epidemiology of diseases to decide which potential diagnoses are most likely.

++

CLINICAL PEARL

There are 3 steps in diagnostic reasoning:

  • Gathering information with a differential diagnosis in mind

  • Identifying the objective abnormalities with the greatest specificity

  • Looking for discriminating features to narrow the differential diagnosis

++

Once the most specific problem has been identified and a differential diagnosis of that problem is considered using discriminating features to order the possibilities, the next step is to consider using diagnostic testing, such as laboratory, radiologic, or pathologic data, to confirm the diagnosis. Clinically, the timing and effort with which one pursues a definitive diagnosis using objective data depends on several factors: the potential gravity of the diagnosis in question, the clinical state of the patient, the potential risks of diagnostic testing, and the potential benefits or harms of empiric treatment. For example, if a 60-year-old active and functioning man is admitted to the hospital with bilateral pulmonary nodules on chest x-ray, there are many possibilities including metastatic malignancy, and aggressive pursuit of a diagnosis is necessary, perhaps including a thoracotomy with an open-lung biopsy. The same radiographic findings in an elderly 90-year-old bed-bound woman with advanced Alzheimer dementia who would not be a good candidate for chemotherapy might be best left alone without any diagnostic testing. Decisions like this are difficult, require solid medical knowledge, as well as a thorough understanding of one's patient and the patient's background and inclinations, and constitute the art of medicine.

++

In other words, judgment, prudence, and diligent counseling of the patient and family are important before embarking on a diagnostic workup, since sometimes the diagnostic interventions are more painful and uncomfortable than the disease itself.

++

Assessing the Severity of the Disease

++

After ascertaining the diagnosis, the next step is to characterize the severity of the disease process; in other words, it is describing “how bad” a disease is. There is usually prognostic or treatment significance based on the stage. With malignancy, this is done formally by cancer staging. Most cancers are categorized from Stage I (localized) to Stage IV (widely metastatic). Some diseases, such as congestive heart failure, may be designated as mild, moderate, or severe based on the patient's functional status, that is, their ability to exercise before becoming dyspneic. With some infections, such as urinary tract infection, the staging depends on the duration and extent of the infection (ie, asymptomatic, simple cystitis, pyelonephritis, and sepsis).

++

Rendering a Treatment Based on the Stage of the Disease

++

Many illnesses are stratified according to severity because prognosis and treatment often vary based on the severity. If neither the prognosis nor the treatment was affected by the stage of the disease process, there would be no reason to subcategorize as mild or severe. As an example, a man with mild chronic obstructive pulmonary disease (COPD) may be treated with inhaled bronchodilators as needed and advised for smoking cessation. However, an individual with severe COPD may need round-the-clock oxygen supplementation, scheduled bronchodilators, and possibly oral corticosteroid therapy. An older individual's physiological reserve should be evaluated, including end organ function.

++

The treatment should be tailored to the extent or "stage" of the disease in the context of the individual patient's circumstances. In making decisions regarding treatment, it is also essential that the clinician identify the therapeutic objectives—is it comfort and being able to spend quality time with family members, or is it cure? When patients seek medical attention, it is generally because they are bothered by a symptom and want it to go away. When physicians institute therapy, they often have several other goals besides symptom relief, such as prevention of short- or long-term complications or a reduction in mortality. For example, patients with congestive heart failure are bothered by the symptoms of edema and dyspnea. Salt restriction, loop diuretics, and bed rest are effective at reducing these symptoms. However, heart failure is a progressive disease with a high mortality, so other treatments such as angiotensin-converting enzyme (ACE) inhibitors and some β-blockers are also used to reduce mortality in this condition. Older individuals are more sensitive to medications and polypharmacy/medication interaction. It is essential that the clinician know what the therapeutic objective is, so that one can monitor and guide therapy.

++

CLINICAL PEARL

  • The clinician needs to identify the objectives of therapy: symptom relief, prevention of complications, or reduction in mortality, and review all medications before prescribing a new agent.

++

Following the Patient's Response to the Treatment

++

The final step in the approach to disease is to follow the patient's response to the therapy. The “measure” of response should be recorded and monitored. Some responses are clinical, such as the patient's abdominal pain, or temperature, or pulmonary examination. Obviously, the student must work on being more skilled in eliciting the data in an unbiased and standardized manner. Other responses may be followed by imaging tests, such as CT scan of a retroperitoneal node size in a patient receiving chemotherapy, or a tumor marker such as the prostate-specific antigen (PSA) level in a man receiving chemotherapy for prostatic cancer. For syphilis, it may be the nonspecific treponemal antibody test rapid plasma reagent (RPR) titer over time. The student must be prepared to know what to do if the measured marker does not respond according to what is expected. Is the next step to retreat, or to repeat the metastatic workup, or to follow up with another more specific test?

++

Part 3. Approach to Reading

++

The clinical problem–oriented approach to reading is different from the classic “systematic” research of a disease. Patients rarely present with a clear diagnosis; hence, the student must become skilled in applying the textbook information to the clinical setting. Furthermore, one retains more information when one reads with a purpose. In other words, the student should read with the goal of answering specific questions. There are several fundamental questions that facilitate clinical thinking. These questions are

++

  1. What is the most likely diagnosis?

  2. What should be your next step?

  3. What is the most likely mechanism for this process?

  4. What are the risk factors (both implicit and age-related) for this condition?

  5. What are the complications associated with the disease process?

  6. What is the best therapy (and does the patient's age change the therapy)?

  7. How would you confirm the diagnosis?

++

CLINICAL PEARL

  • Reading with the purpose of answering the 7 fundamental clinical questions improves retention of information and facilitates the application of “book knowledge” to “clinical knowledge.”

++

What is the Most Likely Diagnosis?

++

The method of establishing the diagnosis was discussed in the previous section. One way of attacking this problem is to develop standard “approaches” to common clinical problems. It is helpful to understand the most common causes of various presentations, such as “the most common causes of delirium in an older patient are medication effect, hypoxia, and sepsis.”

++

The clinical scenario would entail something such as:

++

An 80-year-old woman in a nursing home is acutely agitated and disoriented. What is the most likely diagnosis?

++

With no other information to go on, the student would note that this woman has a clinical diagnosis of delirium. Using the “most common cause” information, the student would make an educated guess that the patient has sepsis. If, instead, information is given regarding new medication added recently a phrase may be added such as:

++

"The patient recently has been depressed and given a new antidepressant." Then the clinical suspicion for medication-induced altered mental status goes up.

++

CLINICAL PEARL

  • Common causes of delirium in an older patient include hypoxia, medications, and sepsis.

++

In contrast, if the further history revealed that the patient had an indwelling urinary catheter, the concern may shift to urosepsis.

++

What Should be Your Next Step?

++

This question is difficult because the next step may be more diagnostic information, or staging, or therapy. It may be more challenging than “the most likely diagnosis,” because there may be insufficient information to make a diagnosis and the next step may be to pursue more diagnostic information. Another possibility is that there is enough information for a probable diagnosis, and the next step is to stage the disease. Finally, the most appropriate action may be to treat. Hence, from clinical data, a judgment needs to be rendered regarding how far along one is on the road of:

++

Make the diagnosis → Stage the disease → Treatment based on stage → Follow response

++

Frequently, the student is “taught” to regurgitate the same information that someone has written about a particular disease, but is not skilled at giving the next step. This talent is learned optimally at the bedside, in a supportive environment, with freedom to make educated guesses, and with constructive feedback. A sample scenario may describe a student's thought process as follows:

++

  1. Make the diagnosis: “Based on the information I have, I believe that Mr. Smith has stable angina because he has retrosternal chest pain when he walks 3 blocks, but it is relieved within minutes by rest and with sublingual nitroglycerin.”

  2. Stage the disease: “I don't believe that this is severe disease because he does not have pain lasting for more than 5 minutes, angina at rest, or congestive heart failure.”

  3. Treatment based on stage: “Therefore, my next step is to treat with aspirin, β-blockers, and sublingual nitroglycerin as needed, as well as lifestyle changes.”

  4. Follow response: “I want to follow the treatment by assessing his pain (I will ask him about the degree of exercise he is able to perform without chest pain), performing a cardiac stress test, and reassessing him after the test is done.”

++

In a similar patient, when the clinical presentation is unclear or more severe, perhaps the best “next step” may be diagnostic in nature such as thallium stress test, or even coronary angiography. The next step depends upon the clinical state of the patient (if unstable, the next step is therapeutic), the potential severity of the disease (the next step may be staging), or the uncertainty of the diagnosis (the next step is diagnostic).

++

Usually, the vague question, “What is your next step?” is the most difficult question, because the answer may be diagnostic, staging, or therapeutic. Additionally, older patients are sometimes placed on “Do Not Resuscitate” orders, and before performing CPR or other interventions, these directives should be reviewed.

++

What is the Most Likely Mechanism for this Process?

++

This question goes further than making the diagnosis, but also requires the student to understand the underlying mechanism for the process. For example, a clinical scenario may describe a “70-year-old woman who presents with several months of severe epistaxis, petechiae, and a normal CBC except for a platelet count of 15,000/mm3.” Answers that a student may consider to explain this condition include immune-mediated platelet destruction, drug-induced thrombocytopenia, bone marrow suppression, and platelet sequestration as a result of hypersplenism.

++

The student is advised to learn the mechanisms for each disease process and not merely memorize a constellation of symptoms. In other words, rather than solely committing to memory the classic presentation of idiopathic thrombocytopenic purpura (ITP) (isolated thrombocytopenia without lymphadenopathy or offending drugs), the student should understand that ITP is an autoimmune process whereby the body produces IgG antibodies against the platelets. The platelets-antibody complexes are then taken from the circulation in the spleen. Because the disease process is specific for platelets, the other 2 cell lines (erythrocytes and leukocytes) are normal. Also, because the thrombocytopenia is caused by excessive platelet peripheral destruction, the bone marrow will show increased megakaryocytes (platelet precursors). Hence, treatment for ITP includes oral corticosteroid agents to decrease the immune process of antiplatelet IgG production, and, if refractory, then splenectomy. In older patients, myelodysplastic processes are more common and need to be considered.

++

What are the Risk Factors (Both Implicit and Age-Related) for this Condition?

++

Understanding the risk factors helps the practitioner to establish a diagnosis and to determine how to interpret tests. For example, understanding the risk factor analysis may help manage a 65-year-old obese woman with sudden onset of dyspnea and pleuritic chest pain following an orthopedic surgery for a femur fracture. This patient has numerous risk factors for deep venous thrombosis and pulmonary embolism. The physician may want to pursue angiography even if the ventilation/perfusion scan result is low probability. Thus, the number of risk factors helps categorize the likelihood of a disease process. Age changes the risk factors and likelihood of disorders, as well as changing the manifestations. For example, because an older patient's immune system wanes, the clinical signs of infection and sepsis may be more subtle.

++

CLINICAL PEARL

  • When the pretest probability of a disease is high based on risk factors, even with a negative initial test, more definitive testing may be indicated.

++

What are the Complications Associated with the Disease Process?

++

A clinician must understand the complications of a disease so that one may monitor the patient. Sometimes the student has to make the diagnosis from clinical clues and then apply his/her knowledge of the sequelae of the pathological process. For example, the student should know that chronic hypertension may affect various end organs, such as the brain (encephalopathy or stroke), the eyes (vascular changes), the kidneys, and the heart. Understanding the types of consequences also helps the clinician to be aware of the dangers to a patient. The clinician is acutely aware of the need to monitor for the end-organ involvement and undertakes the appropriate intervention when involvement is present.

++

What is the Best Therapy (And Does the Patient's Age Change the Therapy)?

++

To answer this question, the clinician needs to reach the correct diagnosis, assess the severity of the condition, and weigh the situation to reach the appropriate intervention. For the student, knowing exact dosages is not as important as understanding the best medication, the route of delivery, mechanism of action, and possible complications. It is important for the student to be able to verbalize the diagnosis and the rationale for the therapy. A common error is for the student to “jump to a treatment,” like a random guess, and therefore being given “right or wrong” feedback. In fact, the student's guess may be correct, but for the wrong reason; conversely, the answer may be a very reasonable one, with only one small error in thinking. Instead, the student should verbalize the steps so that feedback may be given at every reasoning point, and also take into account the patient's age and activity level.

++

For example, if the question is, “What is the best therapy for a 75-year-old man who is diagnosed with a prostatic cancer?” the incorrect manner of response is for the student to blurt out “surgery” or “radiation.” Rather, the student should reason it out in a way similar to this: “This 75-year-old man is highly functional and has no comorbidities. The prostate cancer is low grade and likely cured by surgery.” Or “This 75-year-old man is debilitated and has multiple medical problems making him surgical risk high. The prostatic cancer is a concern, but he is such a high surgical risk that hormonal treatment may be the best option.”

++

CLINICAL PEARL

  • Therapy should be logical based on the severity of disease. Antibiotic therapy should be tailored for specific organisms.

++

How Would You Confirm the Diagnosis?

++

In a situation where a man has a nontender penile ulcer, it is likely to be an infection or a tumor. Confirmation may be achieved by serology (rapid plasma reagent [RPR] or Venereal Disease Research Laboratory [VDRL] test) or biopsy; however, there is a significant possibility that patients with primary syphilis may not have developed antibody response yet, and have negative serology. Thus, confirmation of the diagnosis is attained with dark-field microscopy. Knowing the limitations of diagnostic tests and the manifestations of disease aids in this area.

++

Summary

++

  1. There is no replacement for a careful history and physical examination, which must be conducted with patience and the possibility of cognitive impairment.

  2. There are 4 steps to the clinical approach to the patient: making the diagnosis, assessing severity, treatment based on severity, and following response.

  3. There are 7 questions that help in bridging the gap between the textbook and the clinical arena.

++

References

+
Bordages  G. Elaborated knowledge: a key to successful diagnostic thinking. Acad Med. 1994;69(11):883–885.
+
Bordages  G. Why did I miss the diagnosis? Some cognitive explanations and educational implications. Acad Med. 1999;74(10):138–143.
+
Fitzgerald  FT. History and physical examination: art and science. In: Henderson  M, Tierney  L, Simetana  G. The Patient History: Evidence-Based Approach. 2nd ed. New York, NY: McGraw-Hill; 2012.
+
Gross  R. Making Medical Decisions. Philadelphia, PA: American College of Physicians; 1999.
+
Johnston  CB. Geriatric assessment. In: Landefeld  C, Plamer  R, Johnson  MA  et al., eds. Current Geriatric Diagnosis and Treatment. New York, NY: McGraw-Hill; 2004.
+
Mark  DB. Decision-making in clinical medicine. In: Longo  D, Fauci  AS, Kasper  KL  et al., eds. Harrison's Principles of Internal Medicine. 18th ed. New York, NY: McGraw-Hill; 2011:16–23.