Desensitization has no effect on the incidence of Stevens-Johnson syndrome, hemolytic anemia, or serum sickness associated with penicillin because these are all non-immunoglobulin E (IgE)-mediated reactions. Fatal reactions to penicillin skin tests have been reported, but they occur in <1% of those tested.

The pneumococcal vaccination is recommended in all patients aged 65 years or older. Generally, it should also be given to immunosuppressed patients before their immunosuppression occurs or becomes advanced. Therefore, the vaccination should be given before a planned splenectomy, before the administration of chemotherapy or immunosuppressant therapy, and when HIV infection is first detected. Because of waning immunity, the vaccination should be given every 5 years in a patient with chronic renal failure who received the vaccination previously. Therefore, the correct answer is d.

A common misconception among patients is that the influenza vaccination causes an influenza infection. The vaccine may cause a local skin reaction, fever, myalgia, and malaise, side effects that the patient may mistake for influenza symptoms. The vaccine does not cause influenza because the vaccine is made from an inactivated virus. The vaccine is contraindicated in those allergic to eggs because the vaccine is made from the inactivated virus grown in eggs. It should be postponed in those with a febrile illness. It is 60% to 80% effective and can be given safely at the same time as the pneumococcal vaccination. Therefore, the correct answer is d.

This case raises many important issues encountered in the management of a patient complaining of headache. In this particular case, the history itself is worrisome and is enough to warrant further testing. Although the headaches are mild, for this patient, they are different than the usual pattern. This is probably the most important part of the history in a headache patient. Headaches that have changed in quality are more worrisome than severe headaches that are the same as always. The fact that the headaches respond to mild analgesic medication or to massage should not be reassuring to the physician. All sorts of pains respond to analgesic medication, and this in and of itself does not mean that the cause of the headache is benign. Of the greatest importance is the abnormality in the neurologic examination. A slight but definite pronation of the left arm on extension of the upper limbs indicates a mild left hemiparesis. A positive neurologic examination in the presence of headache should always lead to further evaluation. In some centers, it may be possible to do an MRI, but CT scanning is a more widespread and available technology. For this patient, there is really no reason to obtain skull radiographs or any other noninvasive evaluation other than a CT scan. The CT scan may be done without contrast, at which time a lesion may be found. If nothing is found, a decision about injecting contrast can be made later.

In asymptomatic patients, routine ECGs and screening lab tests, such as urinalysis, complete blood counts, chemistry panels, and liver function tests, are generally not recommended. All major advisory groups recommend BP screening and lipid panel testing by the age of 35 years for all male patients and 45 years for all female patients. High-risk patients are recommended to have screening sooner if they are at increased risk for coronary artery disease. This patient is not at increased risk, and therefore, should have only screening lipids at this time. The U.S. Preventive Services Task Force recommends screening for diabetes in patients with sustained BP greater than 135/85, or at increased risk for impaired glucose tolerance. Assessment for left ventricular hypertrophy, typically with an ECG, is recommended in hypertensive patients only.

An elevated zinc protoporphyrin with a normal blood lead level is most often due to iron deficiency anemia, particularly in a woman of reproductive age. Because these studies were obtained during the preplacement evaluation, the patient has not yet encountered lead exposure in the workplace. The physician always should inquire about possible environmental or household exposures, such as the use of glazed ceramic ware, folk remedies, and lead-soldered water pipes. A completely normal lead level excludes recent or ongoing lead exposure from any source.

Erythropoietic protoporphyria is a rare disorder that results in significant symptoms, including photosensitivity. Thalassemia minor and laboratory error are theoretically possible, but highly unlikely explanations for these results.

Gell and Coombs classification is a classification of the immune mechanisms of tissue injury, comprising four types: type I, immediate hypersensitivity reactions, mediated by the interaction of IgE antibodies and antigens and the release of histamine and other mediators; type II, antibody-mediated hypersensitivity reactions, due to antibody-antigen interactions on cell surfaces; type III, immune complex, local or general inflammatory responses, due to formation of circulating immune complexes and their deposition in tissues; and type IV, cell-mediated hypersensitivity reactions, initiated by sensitized T lymphocytes either by release of lymphokines or by T-cell-mediated cytotoxicity. Contact dermatitis is a type IV cell-mediated response.

Herpes zoster vaccine is recommended for patients aged 60 years and older. Definitive evidence supporting prostate cancer screening is still lacking. Patients born before 1957 are likely to have had the measles virus and need not be vaccinated. Adults born after 1957 who are not previously vaccinated and without demonstrated immunity should receive the vaccine. Advisory groups now list breast self-examination as an optional test because of lack of evidence regarding its effectiveness. Answer e is a true statement—the live attenuated influenza vaccine is only approved for use in patients younger than 50 years.

With both a normal Pap smear and negative HPV screen done 2 years ago, this patient does not need another Pap smear for another 3 years. If she just had a normal Pap smear,
but did not have HPV testing, the U.S. Preventative Services Task Force recommends to repeat cytology screening at 3 years. A Pap smear could be done sooner if this patient were considered to be at high risk for cervical cancer. There is no evidence of that in this patient. A tetanus booster immunization should be administered every 10 years after the primary series is completed. Most major advisory groups recommend cholesterol screening in asymptomatic patients with normal risk of coronary artery disease by 35 years of age for men and 45 years of age for women. Therefore, b is the correct answer.

This 68-year-old man has two separate problems. The first is a tendency not to move, known as akinesia or bradykinesia. This gives him the expressionless face and accounts for his sitting rigidly in a chair with his arms flexed and bent slightly forward. This akinesia is sometimes referred to as Parkinsonism. In addition to the akinesia, he shows the classic tremor of Parkinsonism, which is characterized as a slow alternating tremor with a frequency of about three cycles per second. This tremor is most prominent in the position of repose and improves when the limb moves into action. When a tremor is superimposed on rigidity, the phenomenon of cogwheeling develops. The tremor of his Parkinson disease is probably not bothering him because it is present only in repose and improves on action. His major complaint concerned the deterioration of handwriting. In fact, he is complaining about a second tremor, some form of postural tremor, which could be either an essential tremor or an exaggerated physiologic tremor. Tremor is defined as an alternating movement around some fulcrum. Tremors may be proximal or distal, rapid or slow, and synchronous or alternating. They may be greatest in the position of repose or on action. Action tremors are subdivided into goal-directed action tremors, which are present only when the patient attempts to make projected precise movements, and postural action tremors, which occur when the affected limb attains an antigravity posture, such as raising the hand. The physiologic tremor is a rapid postural action tremor and is most prominent in the distal extremities and interferes with carrying out fine motor activities, such as writing. It is caused by the peripheral action of catecholamines or their agonists on receptors in the muscle. It is usually not symptomatic, but it may become symptomatic, in which case it is called exaggerated physiologic tremor. Physiologic tremor is exaggerated by situations that increase the sensitivity of peripheral catecholamine receptors or increase the amount of circulating catecholamines. Such circumstances include anxiety, hyperthyroidism, or the use of drugs that functionally raise the circulating catecholamine levels, such as anti-asthmatic medications, lithium carbonate, theophylline, and caffeine. This tremor is treated best by reducing the exacerbating factors or, if necessary, with a small dose of β-blocker. Alcohol is also effective against this tremor, but it is not recommended as a therapy. The second form of postural tremor is known as essential tremor. It is slightly slower than the physiologic tremor, is also present in the extremities most commonly, may occur in families, and may develop only in older people (senile essential tremor). Treatment consists of either β-blocker or use of the antiepileptic drug primidone (Mysoline). Evidence suggests that the incidence of essential tremor is higher in patients with Parkinsonism than in agematched controls; that is, it may be true that the action tremor is part of Parkinson disease. It is also possible that this man has an exaggerated physiologic tremor, possibly caused by the peripheral metabolism of Sinemet to norepinephrine, which then acts on receptors in the muscle. A tremor study done in an experienced neurophysiology laboratory might be helpful in distinguishing these two types of tremor, but a therapeutic trial of reduction in Sinemet may work just as well. In this case, the first choice would be to decrease or discontinue his Sinemet. If there was no effect on the tremor, then treatment with primidone or β-blocker would be appropriate.

The use of the estradiol vaginal ring would be an option for local estrogen treatment in a patient with vaginal atrophy and genitourinary symptoms. The estrogen ring provides local estrogen to the vaginal mucosa to help alleviate symptoms of vaginal dryness. The use of nonhormonal over-the-counter vaginal moisturizers and lubricants, including Silk-E and K-Y Jelly, may provide some relief during sexual intercourse. In a woman not on systemic HT, it is important to establish her bone mineral density status because this might affect her decision to initiate HT, or select an alternative therapy with a bisphosphonate (Actonel or Fosamax) or selective estrogen receptor modulator (SERM) such as raloxifene (Evista).

The presence of abnormal vaginal bleeding or spotting in any postmenopausal woman on continuous combined HT should alert the physician to the possibility of endometrial hyperplasia or endometrial cancer. Other causes of spotting include endometrial polyps and uterine fibroids. The next step for therapy would be an endometrial biopsy to further evaluate the endometrial lining for changes. If the endometrial biopsy is benign, consideration should be given to a different HT such as E₂/norgestimate (Prefest), E₂/norethindrone acetate (Activella), or Femhrt (ethinylestradiol/NA), or low-dose Prempro (0.45/1.5 or 0.3/1.5) (which may offer this patient a better chance of amenorrhea).

Because of her history of using phenytoin for seizure disorder, this patient probably metabolizes estrogen at a faster rate than normal. By changing her ET to a transdermal patch, consistent estrogen levels can be maintained, which should alleviate her symptoms. Simply increasing her oral CEE dosage does not account for the fluctuations in metabolism and is less favorable than changing to a transdermal patch. Addition of progestin would not help with the hot flashes. Adding isoflavones and other plant-based estrogens in addition to her ET may or may not also help her symptoms. Other causes for her hot flashes should also be excluded, including checking for the thyroid-stimulating hormone and fasting blood sugar level. The patient will also benefit from a transdermal patch therapy instead of the oral ET due to her elevated triglyceride level. Fasting lipid levels should be periodically monitored.

Vertigo is defined as an illusion of movement and always reflects a disorder of the vestibular system. Vertigo originating from the central nervous system tends to spare hearing, produces less torsional vertigo, and is associated with other brainstem symptoms and signs, such as double vision, dysarthria, and ataxia. The horizontal nystagmus and the eyelid ptosis are concerning for a cerebrovascular stroke and consistent with her recent neck manipulation by her chiropractor. Although uncommon, extreme or abrupt twisting of the neck can damage the inner layer of vertebral arteries.

This patient’s symptoms seem to correlate with a FAD, syndrome requiring therapy. Because she is already on adequate estrogen replacement, the only method currently available for androgen therapy is oral Estratest HS (1.25 methyltestosterone and 0.625 mg of esterified estrogen). At present, no agent is the Food and Drug Administration approved for FAD. She should have periodic monitoring of her triglycerides, cholesterol profile, and free and total testosterone level before and after therapy is initiated as there is an increased risk of cardiovascular disease, presumed to at least be partially related to higher levels of total cholesterol and low-density lipoprotein. Also, ˜20% of women can have side effects of hair loss, deepening of voice, hirsutism, and so on, even with testosterone levels within the normal range, although the risk of this increases substantially with supratherapeutic levels.

This patient has OP on DXA, which is of concern and must be treated. Although calcium supplementation at 1.5 g plus vitamin D, 800 IU/day, is necessary but not sufficient to treat OP, she needs additional treatment to prevent further bone loss. The best option for treatment in this patient is a SERM such as raloxifene. Raloxifene will not only prevent further bone loss but also offer her a breast cancer risk reduction, as well as a decrease in the total cholesterol without an increase in the ultrasensitive C-reactive protein. Because of this patient’s past medical history of esophagitis and gastroesophageal reflux disease, Fosamax or Actonel can still be an option for treatment, but the gastrointestinal symptoms would have to be followed closely. Injectable Forteo, a bonebuilding agent, could be considered.

Seizures can be associated with a sudden alteration of consciousness that may interfere with the activities of daily living or put the patient in a dangerous situation. In general, patients should not drive unless the seizures are under control. Each state within the United States has specific rules about what is meant by the phrase “seizure free for a long enough period.” Generally, this period ranges between 6 and 12 months without a seizure while on an appropriate antiepileptic drug regimen. Some states require that the physician report such cases to the Registry of Motor Vehicles; in other states, this is not necessary. Familiarity with local laws on this subject is recommended. Other activities such as swimming, bathing, operating heavy machinery, and climbing great heights are usually not regulated specifically, but should be avoided when unsupervised.

Two things are important about HIV during pregnancy: first, the management of HIV and HIV-related complications in the mother; and second, minimizing the risk of vertical transmission. The management of HIV and HIV-related complications is similar to the one recommended in the patients who are not pregnant, including the prophylaxis against opportunistic infections. As such, PCP prophylaxis should be initiated with a CD4 count of <200. Either trimethoprim/sulfamethoxazole or aerosolized pentamidine is used for PCP prophylaxis if indicated. Pregnancy does not affect the progression of the disease. In addition, HIV has no effect on the pregnancy course once social factors are controlled for.

The risk of transmission from the mother to the infant is believed to be related to the viral load. The risk of vertical transmission is as high as 33% of infants born to untreated mothers versus less than 7% in those infants born to mothers receiving perinatal antiviral medication.

The optimal timing and route of antivirals is debated, but most experts believe in treating with oral triple therapy (if

possible) from 14 weeks of gestation to delivery followed by intravenous (IV) therapy during labor and oral therapy to the infant for 6 weeks. If triple therapy is not possible, intrapartum zidovudine conveys the most benefit if given alone. If a mother is on antiretrovirals at the time of conception, they should be continued during the first trimester.

Nasal sympathomimetic agents are not to be used for long-term symptom relief. Their use is limited to 2 to 3 days, to avoid the development of rhinitis medicamentosa. In rhinitis medicamentosa, rebound nasal congestion occurs after the discontinuation of a strong nasal decongestant, creating a vicious cycle, with the patient restarting the nasal spray to treat the congestion, which is directly caused by the nasal spray itself.

Minimizing the known risks of maternal hypoxia to the fetus is preferred to minimizing the theoretical risks of medications. Therefore, encouraging compliance with medications is important. Almost all asthma medications are used safely during pregnancy. The exception is epinephrine, which can decrease the uterine perfusion. A better choice is terbutaline, 0.25 mg subcutaneously, which is often used to treat preterm labor.

Insulin does not cross the placenta, but glucose does. The fetus will make its own insulin to respond to the high glucose levels. This leads to hypoglycemia after the umbilical cord is cut, as the glucose supply is interrupted. Both large-for-gestational-age and growth-restricted babies are born to diabetics, depending on the effect on the placenta, which is also an end organ like the kidneys and the eyes. Larger babies tend to have less mature lungs; the mechanism for this is unknown. Miscarriages and birth defects are more common in preexisting diabetics, as opposed to gestational diabetics.

Angiotensin-converting enzyme inhibitors (ACEIs) are associated with fetal compromise and death when exposure occurs during the second and third trimesters. ACEIs are considered class D medications during pregnancy, meaning that they have known teratogenic properties. Methyldopa is a class B medication during pregnancy, indicating that while there are no well-designed human trials, there are no teratogenic effects noted in animal models, and there is no anecdotal evidence of teratogenic effects in humans or there are teratogenic effects in animal models but not in human models. The rest of the medications above are considered class C medications, suggesting that either animal studies have shown risks and there are no human studies, or no animal or human studies have been conducted. Clinically, all the medications listed other than enalapril are used during pregnancy.

In patients with DVT/PE, early anticoagulation with heparin or LMWH decreases mortality. Also, the risk of DVT and PE is increased during pregnancy. Heparin does not cross the placenta and is easily reversed, so immediate anticoagulation carries little risk. Once that is done, do not hesitate to make the definitive diagnosis. Fetal risk from radiation is minimal compared with the risk of untreated DVT or PE, or ongoing anticoagulation without a documented diagnosis. Ventilation-perfusion scanning, spiral CT, angiography, and venography are all worth the risk. Long-term full anticoagulation with heparin or LMWH is preferred to warfarin. A filter is indicated only if anticoagulation cannot be safely accomplished.

Complete the following table using the partial information provided:

The steps to calculate the positive predictive value are as follows:

Step 1. The example specifies a population prevalence of disease X of 20%. Thus, of 100 patients who are tested, 20 are expected to have the condition disease X—that is, the frequencies A and C add to 20.

Step 2. The problem specifies that 40 of the 100 patients tested have a positive test, so A + B is 40, and the other marginal values of the table can be determined by subtracting the known values from 100, which is the total number of patients examined in this example.

Step 3. The specificity of the test is designated to be 60%, so that 60% of the 80 patients without disease X in this example have a negative X-ometry test result. Frequency D is thus 60% of 80, or 48. The frequency in each of the other cells in this 2 × 2 table can then be specified.

Step 4. Once the cells are all filled in, it is possible to calculate the value of the positive predictive value of X-ometry in this example by calculating cell A (=8) divided by the sum of cells A + B (= 8 + 32, or 40). The correct answer for the positive predictive value is therefore 8/40, or 20%, in this example.

Bayes’ theorem can be applied to calculate the positive and negative predictive values given the specified values of sensitivity, specificity, and prevalence. The Bayes’ theorem for positive predictive value is generally calculated with the following equation:

The prevalence is 0.01, so the positive predictive value is (0.01)(0.95)/[(0.01)(0.95) + ((1 – 0.01) (1 – 0.90))], which equals 0.0095/(0.0095 + 0.099), or 0.088.

Likewise, the Bayes’ theorem for negative predictive value is generally calculated with the following equation:

Therefore, the negative predictive value is (1 – 0.01) (0.90)/[(1 – 0.01)(0.90) + (0.01)(1 – 0.95)], which equals 0.891/(0.891 + 0.0005), or 0.999.

The prevalence is 0.10, so the positive predictive value is (0.10)(0.95)/[(0.10)(0.95) + (1 – 0.10)(1 – 0.90)], which equals 0.095/(0.095 + 0.09), or 0.514. Likewise, the negative predictive value is (1 – 0.10)(0.90)/[(1 – 0.10)(0.90) + (0.10) (1 – 0.95)], which equals 0.810/(0.810 + 0.005), or 0.994.

Think about how the positive and negative predictive values changed when the prevalence increased from question 25 to question 26. If one were to hold the sensitivity and specificity of a test, increasing the prevalence of a disease will increase the positive predictive value and decrease the negative predictive value.

In a statistical test, rejecting the null hypothesis given that it is truly false is called the power of the test. This is equivalent to having a diagnostic test reject the presence of “no disease” to conclude that there is disease. Hence, this is analogous to sensitivity, the probability that the diagnostic test indicates there is disease when in fact there is disease present. Likewise, in hypothesis testing, the type I error rate (i.e., significance level) of rejecting the null hypothesis when it is really true is analogous to 1 – specificity of a diagnostic test, the false-positive rate.

In the Western Hemisphere, diabetic retinopathy is the leading cause of blindness in patients younger than 65 years. While all of these conditions are associated with diabetic retinopathy, the leading cause of irreversible vision loss in patients with diabetes is macular edema given the significantly higher prevalence of macular edema compared with these other conditions. Proliferative diabetic retinopathy is rare in the initial stages of the disease, but can be as high as 11% to 15% in the end stages of the disease. Even at this time, nonproliferative diabetic retinopathy is more common. The pathophysiology of visual loss in nonproliferative diabetic retinopathy is most commonly associated with macular edema.

Most corneal ulcers are caused by infections. People who wear contact lenses are at an increased risk for corneal ulcers.
The risk of corneal ulcerations increases 10-fold when using extended-wear soft contact lenses. Patching is not indicated because it creates a warm, dark environment that allows bacterial growth. Once a pathogen has been identified, targeted antibiotic eye drops and oral pain medications are the mainstay of therapy.

The most common ocular problem in patients with rheumatoid arthritis is keratoconjunctivitis sicca or secondary Sjögren syndrome associated with connective tissue disease. Dry eyes occur in 11% to 13% of patients and this condition is characterized by lymphocytic infiltration of lacrimal and salivary glands with subsequent glandular destruction.

Scleritis is the second most common ocular finding, occurring in 1% to 6% of patients with rheumatoid arthritis. Posterior segment lesions due to rheumatoid arthritis are rare.

In the Western Hemisphere, diabetic retinopathy is the leading cause of blindness in patients younger than 65 years; AMD is the most common cause of irreversible blindness in patients older than 65 years. Macular degeneration affects up to 10% of patients between the ages of 65 and 75 years and up to 30% of patients between 75 and 85 years. There are two types of macular degeneration, dry type and wet type. Dry AMD accounts for up to 90% of cases of AMD. Patients will generally get a central visual field loss that is progressive over time.

Retinal detachment occurs when the lining of the eye comes off, thus causing loss of vision. Causes of retinal detachment include ocular trauma, posterior vitreous detachment, traction from an inflamed vitreous, long eyeballs (as in very nearsighted people), family predisposition, degenerative changes in the retina, complications from diabetes, and complications of intraocular surgery, including cataract surgery.

Using the American College of Cardiology and the American Heart Association (ACC/AHA) guidelines, this patient has several clinical risk predictors (h/o type 2 diabetes mellitus and chronic renal insufficiency) and is scheduled for an intermediate-risk surgery. Because his functional class is poor with
activity <4 metabolic equivalent of tasks (METs), he should undergo further risk stratification with noninvasive testing.

Once high risk features have been ruled out (active ischemia, decompensated congestive heart failure, and ventricular arrhythmia), patients going for intermediate-risk surgery should have their functional status assessed. If the patient is able to consistently undergo at least 4 METs of activity, then no further preoperative testing for cardiovascular disease is needed. However, this patient is not able to do 4 METs due to his osteoarthritis and has multiple (at least three) risk factors for coronary artery disease. With an abnormal baseline ECG, stress testing with an imaging modality may be indicated.

Applying the ACC/AHA guidelines to this patient with chronic stable class II angina with excellent functional class would suggest that he did not undergo any further risk stratification with a stress test unless there would be a change in management.

This patient is able to consistently do >4 METs of activity and is safe to proceed to surgery. No further testing is indicated given his good functional capacity.

The presence of active wheezing places this patient at greater risk for postoperative pulmonary complications and increased bronchospasm risk during anesthesia induction. The patient’s surgery should be delayed until her asthma treatment is optimized. The laparoscopic approach may reduce the risk of pulmonary complications compared with the open cholecystectomy, but a level of risk remains because of gaseous peritoneal distention and postoperative pain.

This patient has an ischemic stroke in the posterior-inferior cerebellar artery distribution. The normal CT scan rules out an intracerebral parenchymal hemorrhage. In a previously healthy young person, less common causes of stroke such as vertebral artery dissection should be considered. Vertebral artery dissection often occurs suddenly with or without trauma. Manipulation by chiropractors has been associated with vertebral artery dissection. Symptoms can include neck or posterior head pain, Horner syndrome (ptosis and miosis), dysarthria, dysphagia, decreased pain and temperature sensation of the face and contralateral body, dysmetria, ataxia, and vertigo. MRA is the best choice to diagnose dissection in this patient. Repeat CT scan will show the evolving stroke but not the cause. Carotid ultrasound and transcranial Dopplers do not reliably characterize vertebral artery abnormalities. Lumbar puncture is indicated to evaluate subarachnoid hemorrhage in the setting of a normal CT scan; however, his neurologic examination with localized medullary symptoms would be very uncommon for a subarachnoid bleed.

This patient presents with headache, vertigo, and ataxia, which are the classic presenting symptoms of ischemic or hemorrhagic cerebellar stroke. Although CT scan can exclude hemorrhage, infarcts may not be well visualized early, especially in the brainstem and cerebellum. The patient’s deterioration the following day, with signs of brainstem compression (altered level of consciousness and intractable hiccups), indicates a dire situation, and urgent neurosurgical decompression is required. Peripheral vertigo may be a result of many disorders of the ear, including vestibular neuronitis, benign positional vertigo, vestibular migraine, acoustic neuroma, and Ménière disease, but none of these causes limb ataxia, dysarthria, or hiccups. Headache may accompany vestibular migraine but is not a feature of the other peripheral disorders.

This patient is completely healthy, and the evidence would suggest that ordering routine preoperative blood work would be both unnecessary and costly, and not indicated in this patient’s case. A screening urine analysis is never indicated unless symptoms suggest that the patient may have an underlying infection.

The current evidence and consensus would support discontinuing vitamin E, ginkgo, and garlic about 2 weeks prior to surgery because they may all increase the risk of bleeding. Aspirin irreversibly inhibits the platelet cyclooxygenase and should be stopped 7 to 10 days before surgery. Cervical spine films are indicated in patients with rheumatoid arthritis before they undergo general anesthesia because the presence of severe atlantoaxial disease can cause a compromise of the cervical cord during manipulation of the neck during intubation; however, there is no role for further spine imaging. Although the risk of perioperative adrenal insufficiency is low, it is potentially catastrophic. Stress-dose steroids would be recommended to prevent this.

The acute onset of the change in mental status, the fluctuating course, and the altered level of consciousness are diagnostic of delirium. Although the cognitive dysfunction at night in a new environment (sundowning) can occur in patients with either dementia or delirium, the patient does not have a history of dementia, in which symptoms usually progress over a duration of months to years, and attention and level of consciousness are normal. A head CT scan is rarely useful in the diagnostic evaluation of a patient with delirium and is reserved for patients with new or focal neurologic signs or suspected head trauma. Patients with major depressive disorder often have cognitive dysfunction (“pseudodementia”), but are alert and attentive and do not have a fluctuating course. A clinical trial with hospitalized elderly patients demonstrated a 40% decrease in the incidence of delirium with an intervention that targeted the risk factors for delirium (cognitive impairment, sleep deprivation, immobility, visual and hearing impairment, and dehydration); the total number of days with delirium was also reduced by the intervention.

Recurrent falls occur in patients with disorders of balance and gait, lower extremity weakness (often from muscular deconditioning or atrophy), polypharmacy, and fear of falling. Drugs with cardiovascular (e.g., α-adrenergic blockers and vasodilators) or central nervous system (e.g., benzodiazepines) effects may worsen the postural stability or balance, increasing the risk of falling. Clinical trials provide strong evidence that balance and gait training, low-intensity resistive exercise (e.g., with weights, bands, or tubes), walking, or Tai Chi exercises can reduce the incidence of falls.

The patient has a urinary tract infection and is likely to respond to an antibiotic that will reduce his lower urinary tract symptoms
as well. Acute causes of urinary incontinence can be recalled by the pneumonic DRIP: Delirium, Restricted mobility, Impaction or Iatrogenic (physical restraints and excessive IV fluids) or Infection, Polyuria (glucosuria, loop diuretics, and anticholinergics), or Pharmaceuticals. The transurethral resection of prostate is indicated for men with severe lower urinary tract symptoms and/or bladder outlet obstruction unrelieved by medications, but this patient’s symptoms are acute and not associated with a large postvoid residual urine. An α-adrenergic blocker is often effective in reducing the irritative and obstructive symptoms of benign prostatic hyperplasia, but the patient did not have a history of chronic symptoms and an improvement with these medications might not be seen for several days or weeks. A bladder relaxant might reduce the intensity of the urinary urgency but would not eliminate the infection. A cholinergic agent would not eradicate the infection and might exacerbate the urge symptoms because it increases the detrusor muscle contractions.

The patient probably has deconditioning associated with major surgery and prolonged immobility. With prolonged bed rest, a generalized weakness of the extensor and flexor muscles of the knees and hip muscles is common. Low-intensity exercises, active resistance against flexion or extension, and therapeutic bands or tubes increase muscle strength and lessen the chance of a fall. A β-blocker with intrinsic sympathomimetic activity could cause orthostatic hypotension and more light-headedness. A psychostimulant might be considered for a patient with depression and delayed recovery from surgery but would not increase the muscle strength. A four-prong cane is helpful when patients have weakness in one extremity, but is not indicated for patients with generalized weakness due to deconditioning. An anxiolytic could cause gait impairment and increase the risk of a fall.

The patient has mixed stress and urge incontinence. The stress incontinence is most likely a result of urethral hypermobility, whereas the urge incontinence likely represents an overactive bladder. Although bladder relaxants alone reduce the frequency of incontinent episodes due to urge incontinence, they have little or no effect on stress incontinence. Behavioral therapies (training), including pelvic floor exercise, pelvic floor stimulation, and biofeedback, are more effective than placebo or bladder muscle relaxants for mixed forms of incontinence. In one study, biofeedback to teach pelvic floor muscle control, verbal feedback based on vaginal palpation, and a self-help booklet in a first-line behavioral training program all achieved comparable improvements in urge incontinence in communitydwelling older women. Periurethral injections with bulking agents (collagen) are indicated for intrinsic sphincter deficiency (ISD) and have no effect on urge incontinence. The α-agonists and vaginal estrogen are of questionable value in the treatment of stress incontinence and have no proven effect in women with ISD.

This patient has organophosphate poisoning as evidenced by his muscarinic and nicotinic overactivation, which may include altered mental status, diaphoresis, lacrimation, miosis, urination, defecation, bradycardia, and diffuse wheezing. Atropine blocks the muscarinic effects of organophosphates and should be administered promptly. Pralidoxime chloride (Protopam) reactivates the enzyme cholinesterase by breaking the acetylcholinesterase-phosphate complex. Its advantages over atropine include its ability to reverse muscle paralysis and possibly central nervous system depression.

Decontamination procedures may include removal of contaminated clothing, washing of skin and hair, and, if indicated by route of exposure, emptying the stomach. In severe cases, a patent airway needs to be established for the removal of excess secretions and institution of ventilatory support.

Sodium nitrite is used in cyanide poisoning. It has no role in the management of organophosphate toxicity.

SSRIs are the most often prescribed medication class in depression. While a relatively safe and effective medication class, they are associated with some side effects. Sexual dysfunction is a very common side effect. Patients taking SSRIs (fluoxetine, sertraline, paroxetine, citalopram, and escitalopram) are more likely to report sexual dysfunction than those taking other agents such as bupropion and mirtazapine. The other side effects, notably weight gain and sedation, have been associated with many SSRIs, but not nearly as frequently as sexual dysfunction. QTc prolongation, while reported, is very rare and should often prompt investigation of other medications.

The Diagnostic and Statistical Manual of Mental Disorders criteria include finding a history of many physical complaints beginning before age 30 years that occur over a period of several years and result in a treatment being sought or a significant impairment in the social, occupational, or other area of functioning.

Treating the patient with short but regularly scheduled visits; reassurance; referral to a psychoeducational group, if available, to enhance optimal health; ordering only “necessary” testing; and treating comorbid psychiatric disorders, such as depression, are the cornerstones of managing these cases.

Panic attacks are characterized by intense fear triggering many somatic symptoms when no apparent threat is present. Panic attacks are very debilitating and while most individuals tend to only have one or two, the fear of having recurrent panic attacks can be crippling. Symptoms of panic attacks are generally quick in onset and can mimic a hyperadrenergic state, including chest pain, palpitations, light-headedness, dizziness, shortness of breath, nausea, difficulty swallowing, and paresthesias. Diarrhea is not a characteristic feature of panic attacks and should prompt an investigation of an alternative or concurrent diagnosis. Nausea and abdominal distress may be seen.

Lithium has renal clearance and is not hepatically metabolized. Therefore, any medications that alter sodium excretion and subsequently lithium excretion should be used with caution (e.g., diuretics, ACEIs, and nonsteroidal anti-inflammatory

drugs) because lithium levels may increase to the point of toxicity in only several days.

Haloperidol may alter the cardiac conduction and prolong QT Interval; life-threatening arrhythmias have occurred with therapeutic doses of antipsychotics, but the risk may be increased with doses exceeding recommendations and/or with IV administration (unlabeled route). Haloperidol should be used with caution or avoided in patients with electrolyte abnormalities (e.g., hypokalemia and hypomagnesemia), hypothyroidism, familial long QT syndrome, concomitant medications that may augment QT prolongation, or any underlying cardiac abnormality that may also potentiate the risk.