Questions 101-150 Flashcards
- A 66-year-old male with known GOLD stage 3 COPD is admitted to the hospital with pneumonia. His pneumonia improves and he is discharged with home oxygen because of hypoxemia. He did not require home oxygen before this.
Which one of the following would be most appropriate regarding his future use of home oxygen?
A) Reduce oxygen use to nighttime only
B) Stop oxygen when his course of antibiotics and corticosteroids is completed
C) Reassess the need for oxygen within 3 months
D) Stop oxygen within 6 months
E) Continue oxygen indefinitely
Item 150
ANSWER: C
The American College of Chest Physicians and the American Thoracic Society recommend that for patients discharged on supplemental home oxygen following hospitalization for an acute illness, the prescription for home oxygen should not be renewed without assessing the patient for ongoing hypoxemia (SOR C). The rationale for this recommendation is that hypoxemia often resolves after recovery from an acute illness. The guidelines recommend that a plan be established to reassess the patient no later than 90 days after discharge and that Medicare guidelines and evidence-based criteria should be followed to determine whether the patient meets the criteria for supplemental oxygen.
Continuous oxygen therapy is indicated in patients with COPD and severe hypoxemia. There is good evidence that the addition of home long-term continuous oxygen therapy for COPD increases survival rates in patients with severe hypoxemia, defined as an oxygen saturation less than 90% or a PaO2 less than 8 kPa (60 mm Hg), but not in patients with moderate hypoxemia or nocturnal desaturation.
Continuous supplemental oxygen should be used to improve exercise performance and survival in patients with moderate to severe COPD who have severe daytime hypoxemia. The Centers for Medicare and Medicaid Services (CMS) provides guidelines for supplemental oxygen therapy and sets the standard for nearly all adult oxygen prescriptions. According to these standards, oxygen therapy is covered for patients with a documented PaO2 less than or equal to 55 mm Hg or an oxygen saturation less than or equal to 88% on room air at rest.
- A 32-year-old male presents with a 1-year history of increasing fatigue, polyuria, and a gradual 30-lb weight loss. Serum chemistries reveal a bicarbonate level of 23 mEq/L (N 22–28), a corrected anion gap of 8 mEq/L (N 3–11), and a glucose level of 658 mg/dL (N 60–110). The patient is admitted to the hospital and his serum glucose drops to 174 mg/dL after he is given 2 L of intravenous normal saline and 10 units of regular insulin subcutaneously. He is observed overnight and further laboratory testing is done the next morning.
Which one of the following is more consistent with type 2 diabetes mellitus than with type 1 diabetes mellitus?
A) The patient’s history of weight loss
B) The patient’s response to the initial dose of insulin
C) The time course of symptom onset
D) Morning laboratory studies showing a C-peptide level of less than 1.1 ng/mL (N 1.1–4.4)
Item 149
ANSWER: C
This patient presents with marked hyperglycemia but no evidence of ketoacidosis or nonketotic coma. Differentiating between type 1 and type 2 diabetes mellitus is important for guiding therapy. The gradual onset of symptoms is more consistent with type 2 diabetes mellitus, whereas type 1 diabetes typically has a more rapid onset. Patients with type 1 diabetes typically need lower doses of insulin to correct hyperglycemia, as they lack the insulin insensitivity that is the hallmark of type 2 diabetes. Positive anti-GAD antibodies and low C-peptide at the time of the initial diagnosis are also consistent with type 1 diabetes, although C-peptide levels can also be low in long-standing type 2 diabetes. Weight loss occurs in both types of diabetes mellitus when glucose is profoundly elevated.
- A 28-year-old previously healthy male nonsmoker has a 3-day history of fever and a productive cough. He presents to the urgent care clinic for evaluation after developing pain in the right lower chest when breathing deeply. He has not sought medical care for over 5 years and has never been immunized for influenza.
On examination you note a temperature of 38.6°C (101.4°F), a blood pressure of 136/74 mm Hg, a pulse rate of 90 beats/min, an oxygen saturation of 93% on room air, and a respiratory rate of 20/min. The patient appears uncomfortable but is not in significant distress. The presence of crackles over the right lower anterior chest prompts an order for chest radiography, which reveals an air bronchogram and a patchy alveolar infiltrate involving the medial middle lobe.
Which one of the following treatment options would be most appropriate at this time?
A) Outpatient treatment with oral azithromycin (Zithromax)
B) Outpatient treatment with oral ciprofloxacin (Cipro)
C) Outpatient treatment with oseltamivir (Tamiflu)
D) Inpatient treatment with intravenous ceftriaxone (Rocephin) and oral azithromycin
E) Inpatient treatment with intravenous ceftriaxone and ciprofloxacin
Item 148
ANSWER: A
This patient’s presentation is consistent with community-acquired pneumonia (CAP). Pathogens commonly involved include viruses such as influenza, as well as Mycoplasma pneumoniae and Streptococcus pneumoniae. This patient’s history and findings are most consistent with early lobar pneumonia, given the sputum production, presence of rales, and radiographic findings, and empiric antibiotic treatment is most appropriate. His premorbid history of good health and the lack of findings such as confusion, tachypnea, hypotension, or multilobar infiltrates that would indicate severe CAP make outpatient antibiotic treatment the most appropriate option. He is outside of the time frame when anti-influenza treatments would be expected to be effective, even if influenza seemed likely.
For previously healthy individuals who have not taken antibiotics in the previous 3 months the most appropriate treatment for CAP is empiric treatment with an oral macrolide such as azithromycin, clarithromycin, or erythromycin (level I evidence) or doxycycline (level III evidence). In the presence of comorbidities such as diabetes, alcoholism, or chronic heart, lung, liver, or renal diseases, the treatment of CAP should provide broader coverage with dual antibiotic treatment regimens including combinations of fluoroquinolones, B-lactam drugs, and macrolide options, and hospitalization is often indicated.
- During a preparticipation examination of a 5-year-old male for summer soccer camp, his mother states that he frequently awakens during the night with complaints of cramping pain in both legs, and that he seems to experience this after a day of heavy physical activity. She says that she has never noticed a definite limp. A physical examination of the hips, knees, ankles, and leg musculature is entirely normal.
Which one of the following would be the most appropriate next step in the evaluation and management of this patient?
A) Reassurance, with no activity restrictions or treatment
B) Recommending that he not participate in running sports
C) Plain films of both hips and knees
D) Serum electrolyte levels
E) Referral to a pediatric orthopedist
Item 147
ANSWER: A
Benign nocturnal limb pains of childhood (growing pains) occur in as many as one-third of children, most often between 4 and 6 years of age. The etiology is unknown, but the course does not parallel pubescent growth, as would be expected if bone growth were the source of the pain. Pain often awakens the child within hours of falling asleep following an active day. It is generally localized around the knees, most often in the shins and calves, but also may affect the thighs and the upper extremities. A characteristic history coupled with a normal physical examination will confirm the diagnosis. Reassurance that no additional tests or treatments are necessary and that the condition is self-limiting is the most appropriate response.
- A 30-year-old male presents to the emergency department after spraining his ankle while playing basketball. He has pain over the lateral malleolus.
Radiographs of the ankle would be indicated if he has which one of the following?
A) An inversion injury B) Swelling over the lateral malleolus C) Ecchymosis over the lateral malleolus D) The inability to bear weight to walk since the injury E) A previous history of ankle injury
Item 146
ANSWER: D
The Ottawa Ankle Rules should be used to rule out fracture and prevent unnecessary radiographs. According to these guidelines, ankle radiographs are needed if there is pain over the malleolus plus bony tenderness over potential fracture areas, or an inability to bear weight and walk four steps immediately after the injury and in the emergency department or physician’s office (SOR A).
- The National Weight Control Registry includes individuals who have lost substantial weight without surgery, and have maintained the weight loss for an average of 5 years. Which one of the following behaviors is typical of these individuals?
A) Eating breakfast every day
B) Taking daily vitamin and mineral supplements
C) Weighing themselves daily
D) Being physically active >2 hours a day
E) Eating a low-protein diet
Item 145
ANSWER: A
Individuals on the National Weight Control Registry typically eat a low-fat diet rich in complex carbohydrates, eat breakfast daily, weigh themselves at least once a week, and are physically active for 60–90 minutes a day.
- A patient with advanced dementia is bed-bound and requires total assistance with all activities of daily living. She was treated recently for pneumonia, which has raised concerns that she is aspirating. Her oral intake has decreased and is not adequate for the patient’s nutritional requirements. She does not have an advance directive. You schedule a family conference.
Which one of the following is your recommended approach to this problem?
A) Clear liquids B) Intravenous fluids C) Hand feeding D) Percutaneous endoscopic gastrostomy (PEG) tube feeding E) Nasogastric tube feeding
Item 144
ANSWER: C
The American Geriatrics Society (AGS) position statement on feeding tubes states that percutaneous feeding tubes are not recommended for older adults with advanced dementia, and that careful hand feeding should be offered instead. This is the first recommendation by the AGS in the Choosing Wisely campaign.
Careful hand feeding for patients with severe dementia is at least as good as tube feeding with regard to the outcomes of death, aspiration pneumonia, functional status, and patient comfort. Regular food is preferred. Tube feeding is associated with agitation, increased use of physical and chemical restraints, and worsening pressure ulcers.
The preponderance of evidence does not support the use of tube feedings, based upon expert opinion and extensive observational data. Published empirical work using observational data is highly consistent regarding the lack of efficacy for tube feeding in this population.
- In a woman whose group B Streptococcus status is unknown, which one of the following is a risk factor requiring empiric intrapartum antibiotic prophylaxis against early-onset group B streptococcal infection in her newborn?
A) Fetal tachycardia
B) Delivery at less than 35 weeks gestation
C) Rupture of the membranes 12 hours before delivery
D) Gestational diabetes during the pregnancy
E) Use of vacuum extraction during delivery
Item 143
ANSWER: B
Of the choices listed, prematurity is the greatest risk factor for group B streptococcal infection. The most important risk would be signs or symptoms of sepsis in a neonate. The other conditions listed are not risk factors for early-onset GBS in neonates.
- A 47-year-old male is hospitalized for severe lower-extremity methicillin-resistant Staphylococcus aureus (MRSA) cellulitis. He is started on intravenous vancomycin and his home medications, which include metoprolol and escitalopram (Lexapro), are continued. On day 3, in preparation for discharge, he is transitioned to oral trimethoprim/sulfamethoxazole (Bactrim). Two hours after taking his first dose he reports severe swelling of his lips, wheezing, hoarseness, and hives. His blood pressure, which was previously normal, is now 84/62 mm Hg. You order emergent therapy with intramuscular epinephrine, 0.3 mg; intravenous methylprednisolone sodium succinate (Solu-Medrol), 125 mg; and intravenous diphenhydramine (Benadryl), 50 mg. However, no clinical improvement is noted after 15 minutes.
Which one of the following should you recommend now?
A) Another dose of intramuscular epinephrine
B) Another dose of intravenous methylprednisolone
C) Another dose of intravenous diphenhydramine
D) Intramuscular glucagon
E) Intramuscular betamethasone sodium phosphate/betamethasone acetate (Celestone
Soluspan)
Item 142
ANSWER: D
Patients taking B-blockers may be resistant to treatment with epinephrine. Glucagon has positive inotropic and chronotropic effects that are not mediated through B-receptors, and should be administered to anaphylactic patients on B-blockers when their response to epinephrine is either poor or absent. In patients not taking B-blockers a repeat dose of epinephrine is recommended when the response to the first dose is either poor or absent. Intravenous methylprednisolone and diphenhydramine may also be repeated based on clinical response (SOR C). An H2-blocker such as cimetidine may provide additional benefit in combination with an H1 antihistamine. In an emergency situation such as this, there is no benefit to using a long-acting corticosteroid.
- A 23-year-old female presents with menstrual irregularity, increased facial hair, and acne. Your evaluation leads to a diagnosis of polycystic ovary syndrome.
Which one of the following is the first-line management for her constellation of symptoms?
A) Clomiphene (Clomid) B) Hormonal contraceptives C) Metformin (Glucophage) D) Pioglitazone (Actos) E) Spironolactone (Aldactone)
Item 141
ANSWER: B
Hormonal contraceptives are the first-line therapy for menstrual abnormalities, hirsutism, and acne in polycystic ovary syndrome. Clomiphene is used for infertility. Thiazolidinediones have an unfavorable risk-benefit ratio overall. Metformin is beneficial for metabolic/glycemic abnormalities and menstrual irregularities, but does not improve hirsutism or acne. Spironolactone may be used as an add-on to hormonal contraceptives for treatment of hirsutism and acne.
- A 7-year-old female is brought to your office with a complaint of right hip pain and a limp with an insidious onset. There is no history of injury or repetitive use. Her vital signs are within normal limits and she has no history of fever or chills or other systemic symptoms. On examination you note that she cannot fully abduct her hip and she winces with pain on internal rotation. A FABER test is normal. Her right leg is 2 cm (æ in) shorter than the left. Plain films reveal flattening and sclerosis of the proximal femur with joint space widening.
What is the most likely diagnosis in this patient?
A) Iliopsoas bursitis B) Labral tear C) Legg-Calvé-Perthes disease D) Septic arthritis E) Stress fracture
Item 140
ANSWER: C
Legg-Calvé-Perthes disease results from interruption of the blood supply to the still-growing femoral head. It occurs in children 2–12 years of age and presents with hip pain and an atraumatic limp. Common physical findings include leg-length discrepancies, and limited abduction and internal rotation. Radiographs reveal sclerosis of the proximal femur with joint space widening. MRI confirms osteonecrosis.
Septic arthritis also causes atraumatic anterior hip pain but occurs in the acutely ill, febrile patient. A CBC, erythrocyte sedimentation rate, C-reactive protein level, and guided hip aspiration are recommended if septic arthritis is suspected. A diagnosis of stress fracture should be considered in patients with a history of overuse and weight-bearing exercise. These patients have pain that is worse with activity, and pain on active leg raising. MRI can detect fractures not seen on plain films.
Iliopsoas bursitis presents with snapping or popping of the hip on extension from a flexed position. Labral tears present with sharp anterior hip pain at times, with radiation to the thigh or buttock. Usually patients will have mechanical symptoms such as clicking with activity. The FABER (flexion, abduction, external rotation) and FADIR (flexion, adduction, internal rotation) impingement tests are sensitive for labral tears.
- A 25-year-old male presents to your office after recently being diagnosed with HIV infection at the health department. You obtain blood work and note that his CD4+ count is 180 cells/mm3.
This patient should receive prophylaxis against which one of the following opportunistic infections?
A) Histoplasma capsulatum B) Microsporidiosis C) Mycobacterium avium-intracellulare complex D) Pneumocystis E) Toxoplasma gondii
Item 139
ANSWER: D
Patients with HIV infection and severe immunodeficiency are at risk for certain opportunistic infections. Susceptibility to opportunistic infections can be measured by CD4+ T lymphocyte counts. Patients with a CD4+ count less than 200 cells/mm3 should receive trimethoprim/sulfamethoxazole for prevention of Pneumocystis pneumonia, and prophylaxis against Toxoplasma gondii should also be given if the CD4+ level is less than 100 cells/mm3. Azithromycin is used to prevent infection with Mycobacterium avium-intracellulare complex when CD4+ counts are less than 50 cells/mm3. Itraconazole is used to prevent Histoplasma capsulatum infection when the CD4+ count is less than or equal to 150 cells/mm3 if the patient is at risk due to occupational exposure or living in a community with a hyperendemic rate of histoplasmosis (greater than 10 cases per 100 patient years). There is no recommendation for prophylaxis against microsporidiosis.
- A 52-year-old female with a history of well-controlled diabetes mellitus presents with right shoulder pain for 2 months. She cannot recall any injury. The pain is fairly constant, has a burning quality, and disturbs her sleep.
On examination the patient has no redness or swelling. Passive and active abduction are limited to 45°. There is some limitation of shoulder flexion and internal rotation, but it is less pronounced. No focal tenderness is found. Plain films are negative.
Which one of the following is the most likely diagnosis for this patient?
A) Calcific tendinitis B) Diabetic neuropathy C) Partial rotator cuff tear D) Locked posterior dislocation E) Frozen shoulder
Item 138
ANSWER: E
Frozen shoulder is an inflammatory contracture of the shoulder capsule and mostly affects the anterosuperior and anteroinferior capsular ligaments, limiting glenohumeral movement. Diabetic patients have a 10%–20% lifetime risk of frozen shoulder. Only two other common conditions selectively limit passive external rotation: locked posterior dislocation and osteoarthritis. Plain films of the shoulder should reveal both conditions. Rotator cuff tears do not limit passive range of motion, and calcific tendinitis has a characteristic radiographic appearance.
- A 75-year-old female presents with a complaint of paresthesias in her feet. On examination she has mild erythema of her tongue and decreased vibratory sensation in her feet. A CBC reveals a hemoglobin level of 11.1 g/dL (N 12.0–16.0) and a mean corpuscular volume of 105 :m3 (N 78–102).
The patient takes the following over-the-counter drugs: aspirin, 81 mg/day; ranitidine (Zantac), 150 mg twice daily; and acetaminophen, 325 mg twice daily. Which one of the following prescription medications the patient takes is most likely causing her problem?
A) Hydrochlorothiazide B) Lisinopril (Prinivil, Zestril) C) Amlodipine (Norvasc) D) Simvastatin (Zocor) E) Omeprazole (Prilosec)
Item 137
ANSWER: E
The use of gastric acid inhibitors, particularly when a proton pump inhibitor and H2-receptor antagonist are combined, is significantly associated with vitamin B12 deficiency. This is more common when combined therapy has been used for 2 years or longer. Because gastric acid is required for the liberation of vitamin B12 bound to food protein before it is bound to intrinsic factor for absorption, suppression of gastric acid may lead to vitamin B12 deficiency.
- Which one of the following screening practices is recommended for the adolescent population
by the U.S. Preventive Services Task Force?
A) Lipid screening
B) Scoliosis screening
C) Testicular examination
D) Papanicolaou tests starting 3 years after first sexual intercourse
E) Chlamydia screening in sexually active females
Item 136
ANSWER: E
The U.S. Preventive Services Task Force recommends screening for Chlamydia infection in all sexually active, nonpregnant young women under the age of 25 (grade B recommendation). Papanicolaou testing is recommended starting at 21 years of age. Testicular cancer screening, whether by self-examination or as part of the physical examination, is not recommended. Scoliosis screening for asymptomatic adolescents is also not recommended. There is insufficient evidence to recommend for or against lipid screening.
- A 38-year-old female presents to the emergency department with an acute onset of fever, chills, and rapidly progressive right lower extremity redness. She reports being in her usual state of health until a few hours ago when she developed shaking chills and noted a fever of 103.0°F (39.4°C).
Shortly after she arrives she complains of right lower extremity pain and a bright red skin discoloration from her ankle to her right knee. She is also noted to have a heart rate of 123 beats/min and a WBC count of 22,000/mm3 (N 4300–10,800). Her past medical history is significant for congenital arthritis, a recent bilateral hip replacement, and recurrent lower extremity cellulitis.
You admit the patient to the hospital. When selecting an empiric treatment for this patient, which
one of the following organisms should you be most concerned about?
A) Candida albicans B) Chlamydia trachomatis C) Mycoplasma hominis D) Group A Streptococcus E) Trichophyton rubrum
Item 135
ANSWER: D
This patient has rapidly progressive erythema and pain in her right lower extremity, along with fever, tachycardia, and leukocytosis. Group A Streptococcus (GAS) is a common monomicrobial cause of type II necrotizing skin infections, which are often referred to as necrotizing fasciitis and warrant immediate attention (SOR C). Type I infections are often polymicrobial due to combinations of staphylococci (especially Staphylococcus epidermidis in combination with B-hemolytic streptococci), enterococci, Enterobacteriaceae species (commonly Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, and Pseudomonas aeruginosa), streptococci, Bacteroides/Prevotella species, anaerobic gram-positive cocci, and Clostridium species.
For this patient with a suspected necrotizing skin infection, aggressive treatment with a broad-spectrum empiric antibiotic is recommended along with hemodynamic support and consideration of surgical exploration and debridement of necrotic tissue (SOR C). Empiric antibiotic treatment of a potential necrotizing infection should consist of broad-spectrum antimicrobial therapy with activity against gram-positive, gram-negative, and anaerobic organisms; special consideration should be given to group A Streptococcus, Clostridium species, and methicillin-resistant Staphylococcus aureus (MRSA).
- A 50-year-old female with significant findings of rheumatoid arthritis presents for a preoperative evaluation for planned replacement of the metacarpophalangeal joints of her right hand under general anesthesia. She generally enjoys good health and has had ongoing medical care for her illness.
Of the following, which one would be most important for preoperative assessment of this patient’s surgical risk?
A) Resting pulse rate B) Resting oxygen saturation C) Erythrocyte sedimentation rate D) Rheumatoid factor titer E) Cervical spine imaging
Item 134
ANSWER: E
While all of the options listed may have some value in evaluating the preoperative status of a patient with long-standing rheumatoid arthritis, imaging of the patient’s cervical spine to detect atlantoaxial subluxation would be most important for preventing a catastrophic spinal cord injury during intubation. In many cases cervical fusion must be performed before other elective procedures can be contemplated. Although rheumatoid arthritis may influence oxygen saturation and the erythrocyte sedimentation rate, these tests would not alert the surgical team to the possibility of significant operative morbidity and mortality. Resting pulse rate and a rheumatoid factor titer are unlikely to be significant factors in this preoperative scenario.
- A 45-year-old male is hospitalized for the management of alcohol withdrawal syndrome. His symptoms include tachycardia, diaphoresis, tremors, and visual hallucinations. His CIWA-Ar (Clinical Institute Withdrawal Assessment for Alcohol, Revised) score is 18, indicating moderate alcohol withdrawal.
Which one of the following medications has been shown to reduce the risk of developing seizures in this situation?
A) Carbamazepine (Tegretol) B) Lorazepam (Ativan) C) Gabapentin (Neurontin) D) Phenytoin (Dilantin) E) Valproic acid (Depakene)
Item 133
ANSWER: B
Benzodiazepines play a key role in the management of alcohol withdrawal syndrome (AWS), especially as they are highly effective in the prevention and treatment of seizures associated with this syndrome. In general, nonbenzodiazepine anticonvulsants are not effective for preventing seizures in patients with AWS. Therefore, their use is not recommended in those at risk for seizures or those who have a CIWA-Ar score in the moderate or severe range. The potential for abuse with these agents is much lower than with benzodiazepines, and they are preferred over benzodiazepines for outpatient management of AWS, especially in those with a past history of substance abuse. Carbamazepine and valproic acid may be effective for managing the symptoms associated with AWS. Gabapentin has been shown to be as effective as lorazepam in treating AWS and reducing alcohol use during withdrawal. Phenytoin is not effective for the treatment or prevention of seizures associated with AWS (SOR B).
- While making rounds on the rehabilitation floor of your hospital, you see a 62-year-old female who was recently transferred from the acute-care section of the hospital where she was admitted for urosepsis. She is a liver-transplant recipient and her specialist has been tapering her immunosuppressive drug regimen for the last 2 months. According to the nursing staff the patient became hypoxic suddenly and had a low-grade fever and cough. You note that she looks ill and uncomfortable, and has an increased respiratory rate. A chest radiograph reveals diffuse bilateral interstitial infiltrates.
Which one of the following is the most likely diagnosis?
A) Pneumococcal pneumonia B) Staphylococcal pneumonia C) Pneumocystis pneumonia D) Pulmonary tuberculosis E) Pneumothorax
Item 132
ANSWER: C
The most likely diagnosis is Pneumocystis pneumonia. Initially named Pneumocystis carinii, the causative organism has been reclassified and renamed Pneumocystis jiroveci. It causes disease in immunocompromised patients. In non–HIV-infected patients, the most significant risk factors are defects in cell-mediated immunity, glucocorticoid therapy, use of immunosuppressive agents (especially when dosages are being lowered), hematopoietic stem cell or solid organ transplant, cancer, primary immunodeficiencies, and severe malnutrition.
The clinical presentation in patients without HIV/AIDS is typically an acute onset of hypoxia and respiratory failure, associated with a dry cough and fever. Characteristic radiographic findings include diffuse bilateral interstitial infiltrates.
Pneumococcal pneumonia typically presents with fever, chills, cough, and pleuritic chest pain. A sudden onset of severe hypoxia is less common. Radiologic findings typically include lobar infiltrates or bronchopneumonia (with a segmental pattern of infiltrate), whereas diffuse bilateral infiltrates are much less common. Staphylococcal pneumonia usually has radiologic findings of focal, multiple infiltrates or cavitary lesions.
Pulmonary tuberculosis presents most commonly with pleuritic or retrosternal chest pain. Fever is present in about 25% of patients. Cough is actually less common, and a sudden onset of acute hypoxia would be a very rare presentation. Radiographs typically reveal hilar adenopathy and pleural effusion. Diffuse bilateral interstitial infiltrates would be a very rare finding.
Spontaneous pneumothorax does present with an acute onset of hypoxia, tachypnea, and respiratory distress. However, fever would be unlikely and the radiologic findings in this patient are not consistent with pneumothorax.
- A 20-year-old college student who has been working in the woods on a forestry project presents with a 3- to 4-day history of a severely pruritic rash on his arms, hands, and face. There is erythema with multiple bullae and vesicles, some of which are in a streaked linear distribution on the arms. There are patches of erythema on his face with some vesicles. The itching is intense and he sleeps fitfully.
In addition to cool compresses and antihistamines for the itching, which one of the following is the best treatment option for this patient?
A) Triamcinolone, 20 mg intramuscularly as a single dose
B) A 6-day oral methylprednisolone (Medrol) dose pack, starting at 24 mg
C) A 7- to 10-day course of topical halobetasol propionate (Ultravate), 0.05% ointment
D) A 7- to 10-day course of topical mupirocin (Bactroban) 2%, after decompression of vesicles and bullae
E) A 10- to 14-day tapering course of oral prednisone, starting at 60 mg
Item 131
ANSWER: E
Poison ivy dermatitis is caused by urushiol, a resin found in poison ivy, poison oak, and poison sumac plants. Direct contact with the leaves or vines will result in an acute dermatitis manifested initially by erythema, and later in more severe cases by vesicles and bullae. This is a type IV T cell–mediated allergic reaction, so it typically takes at least 12 hours and often 2–3 days before the reaction is fully manifested. Depending on the degree of contact (i.e., the amount of resin on the skin), the rash often progresses over a couple of days, giving the impression that it is spreading. Also, delayed contact with resin from contaminated clothing, gloves, or pets may result in new lesions appearing over several days. Brushing against the leaves of the plant causes the linear streaking pattern characteristic of poison ivy dermatitis. It has been demonstrated that the resin can be inactivated with any type of soap, thereby preventing the reaction, but the sooner the better. Approximately 50% of the resin can be removed by soap and water within 10 minutes of contact, but after 30 minutes only about 10% can still be removed.
Therapy depends on the severity of the reaction. Group I–V topical corticosteroids are effective for limited eruptions (less than 3%–5% body surface area) but are ineffective in areas with vesicles or bullae. Group I–II fluorinated agents are at the strongest end of the spectrum and are not recommended for use on the face or intertriginous areas. Short bursts of low-potency oral corticosteroids such as a methylprednisolone dose pack have a high rate of relapse as the taper finishes, so the expert consensus is to use a higher dosage tapered over a longer period, generally 10–14 days, in order to prevent a relapse. Most experts recommend oral corticosteroids over intramuscular corticosteroid suspensions, which may not provide high enough concentrations in the skin (SOR C). However, 40–80 mg of intramuscular triamcinolone (or an equivalent) is an alternative to oral treatment, especially if adherence is an issue. Pruritus can be treated with oral antihistamines. Secondary infection, which is common with vesiculobullous involvement, is treated with appropriate oral antibiotics.
