Questions 151-200

Question 1

151. A 2-year-old male is brought to your office for a well child examination. Developmental screening reveals that he has about a 10-word vocabulary. His mother attributes this to their bilingual home but admits she is concerned about autism.

Which one of the following behaviors would provide additional evidence that the child may have autism?

A) Use of gestures rather than words to communicate ideas

B) Frequently being engrossed in pretend play with dolls

C) Becoming upset by normal noises

D) Seemingly excessive attempts to attract attention with his behavior

E) Repeated copying of parental facial expressions

Answer 1

ANSWER: C

Evidence shows that early treatment of autism is beneficial (SOR B), and the American Academy of Pediatrics recommends screening with a validated autism-specific tool such as the MCHAT at 18 and 24 months (SOR C). Delayed social development is typically the first sign of autism. Language delay can be another finding, but it is less specific. Of the behaviors listed, only abnormal sensitivity to sound is consistent with autism. Gesturing, pretend play, mimicking, and attempting to attract caregiver attention all suggest other diagnoses.

Question 2

152. A 16-year-old female presents for follow-up after a tibial stress fracture. The fracture was diagnosed 5 weeks ago by characteristic physical examination findings and radiographs showing a transverse fracture of the tibial diaphysis. She was placed on non–weight-bearing status for 2 weeks and after that was advised to limit activities that caused discomfort. In addition, she was placed on appropriate calcium and vitamin D supplementation based on results of her laboratory workup. The patient is a basketball player and would like to begin practicing with the team in 1 week. She says she is now able to walk without discomfort but has not tried running or jumping.

Which one of the following is necessary for this patient to be able to return to basketball participation next week?

A) Consultation with a sports medicine physician

B) A normal physical examination of the affected area

C) Normal radiographs of the tibia

D) A normal hydroxyvitamin D level

Answer 2

ANSWER: B

Stress fractures are common in teenage athletes. Because this patient has a normal physical examination and can walk without pain, she can return to basketball as long as her symptoms do not return.

Most stress fractures heal in 6–10 weeks with conservative management such as non–weight bearing and activity limitation. Athletes can return to play once they are pain free and have a normal physical examination, even if the time since diagnosis is less than 6 weeks. However, they should refrain from all high-impact activities such as running and jumping until they can walk without pain. Repeat radiographs are rarely indicated. Calcium and vitamin D supplementation are recommended as part of the management of stress fractures, but checking blood levels of vitamin D is not necessary either at the time of the injury or prior to return to play. Most stress fractures in low-risk locations such as the tibia can be managed in a primary care office without consulting a sports medicine or orthopedic physician. Fractures in high-risk locations are at increased risk for malunion and thus are often managed by specialists. This patient has a low-risk stress fracture.

Question 3

153. A 28-year-old male has had bright red blood in his semen with his last three ejaculations. He is sexually active. He considers himself in good health, takes no medications, has no other symptoms to suggest a coagulopathy, and has no other genitourinary symptoms. Examination of the testes shows no masses or tenderness. Findings on a digital rectal examination are normal.

Which one of the following would be appropriate at this time?

A) Coagulation studies including a platelet count and a prothrombin time

B) A serum PSA level

C) A urine probe for Neisseria gonorrhoeae and Chlamydia trachomatis

D) CT of the pelvis

E) Referral to a urologist

Answer 3

ANSWER: C

In males younger than 40, hematospermia is usually benign and self-limited. Examination of the testes and prostate is warranted but findings are usually normal. If the patient is sexually active a screen for STDs is reasonable. Imaging of the genitourinary tract, a serum PSA level, and urology referral are unnecessary in this age group unless the history or physical examination suggests an unusual cause.

Question 4

154. A 34-year-old female with newly diagnosed diarrhea-predominant irritable bowel syndrome (IBS) presents with worsening abdominal discomfort. Her abdominal discomfort is not severe but it is constant. She has tried dicyclomine (Bentyl) without relief and is interested in trying a different approach.

The patient has had negative testing for inflammatory bowel disease and celiac disease, along with normal blood tests. She asks about specific dietary modifications or medications that may be helpful for her abdominal discomfort.

Which one of the following interventions would you recommend?

A) Amitriptyline

B) Clarithromycin (Biaxin)

C) Loperamide (Imodium)

D) Increased intake of insoluble dietary fiber

Answer 4

ANSWER: A

Tricyclic antidepressants (TCAs) such as amitriptyline have shown benefit in patients with irritable bowel syndrome (IBS), as have SSRIs. Because of the anticholinergic properties of TCAs it is thought that TCAs may be more beneficial than SSRIs in patients with diarrhea-predominant IBS, such as this patient.

Unfortunately, studies have not shown a significant benefit from increasing either insoluble or soluble fiber to the diet of patients with IBS. Although increasing fiber may help improve constipation in patients with constipation-predominant IBS, this does not improve abdominal pain. In some studies adding insoluble fiber resulted in either worsening of symptoms or no change in symptoms.

Clarithromycin was studied in a single randomized, controlled trial and found not to be effective compared with placebo. Loperamide has not been successful for reducing abdominal pain compared with placebo in patients with IBS.

Question 5

155. A 22-year-old male presents to your office for evaluation of fatigue, poor appetite, and nausea. He states that when he stands too long he often gets dizzy but this is relieved by sitting. His symptoms have been gradually getting worse over the past year. His vital signs are normal but he is found to be orthostatic. A physical examination is unremarkable except for hyperpigmentation in his palmar creases and around his nipples. A basic metabolic panel is notable for a sodium level of 131 mEq/L (N 135–145) and a potassium level of 5.1 mEq/L (N 3.5–5.0).

Which one of the following is the most likely cause of this patient’s symptoms?

A) Addison’s disease

B) Cushing syndrome

C) Neurally mediated hypotension

D) Postural orthostatic hypotension and tachycardia syndrome

E) Hypothyroidism

Answer 5

ANSWER: A

This patient presents with classic symptoms of Addison’s disease, which is an autoimmune adrenalitis in which the adrenal cortex is destroyed. This results in the loss of mineralocorticoid, glucocorticoid, and adrenal androgen hormone production. Common symptoms of Addison’s disease include anorexia, weakness, fatigue, gastrointestinal symptoms, hypotension, salt cravings, postural dizziness, vitiligo, muscle pain, and joint pain. Hyperpigmentation is the most common physical finding and is generally distributed diffusely over the entire body. It can also be seen in the palmar creases, at the vermillion border of the lips, on the buccal mucosa, around the nipples, and around scars.

Low serum cortisol measured at 8 a.m. suggests adrenal insufficiency. Hyponatremia may also be seen, due to cortisol and mineralocorticoid deficiencies, and hyperkalemia may occur as a result of the lack of mineralocorticoids. If cortisol is low, a cosyntropin stimulation test is the first-line test for diagnosing adrenal insufficiency.

People with Addison’s disease require lifelong hormone therapy with glucocorticoids and mineralocorticoids. They also require stress-dose glucocorticoids for illnesses and before surgical procedures because they are unable to mount an adequate response to stress. Generally, the treatment will be prednisone or hydrocortisone along with fludrocortisone. Men with Addison’s disease do not need testosterone replacement because their testes will produce adequate levels. Women may benefit from testosterone replacement because the adrenal glands are their primary source of testosterone.

Question 6

156. A 26-year-old female has had a severe anaphylactic reaction to eggs in the past. Which one of the following influenza vaccines would be safest for her?

A) Live attenuated trivalent influenza vaccine

B) Recombinant trivalent influenza vaccine

C) Inactivated trivalent influenza vaccine

D) Inactivated quadrivalent influenza vaccine

Answer 6

ANSWER: B

Recombinant influenza vaccine is formulated without using eggs. Live attenuated influenza vaccine comes only in a trivalent formulation. The other vaccines listed are all prepared using eggs.

Question 7

157. A 35-year-old male with a 4-month history of pain in the medial aspect of his right knee sees you for follow-up. He has been doing physical therapy for the past month with minimal benefit. A plain radiograph is negative and MRI shows a tear in the medial meniscus.

Which one of the following is most likely to yield the best long-term result?

A) Referral for meniscectomy

B) Corticosteroid injection

C) Hylan GF 20 (Synvisc) injection

D) Continued physical therapy

E) A knee brace

Answer 7

ANSWER: D

Arthroscopic partial meniscectomy is the most common orthopedic procedure performed in the United States. For patients without osteoarthritis of the knee, studies show meniscectomy for a tear of the meniscus is no more beneficial than conservative therapy in terms of functional status at 6 months. In a high-quality randomized, controlled trial involving patients with a medial meniscus tear but no osteoarthritis, meniscectomy and sham surgery were equally effective (SOR B). The optimal approach in patients with a degenerative tear of the meniscus is a physical therapy and exercise regimen.

Question 8

158. Which one of the following effects of antioxidant supplementation has been demonstrated in randomized clinical trials?

A) Decreased mortality with vitamin A supplementation

B) Decreased mortality with B-carotene supplementation

C) Decreased mortality with vitamin E supplementation

D) Increased mortality with some antioxidant supplements

Answer 8

ANSWER: D

Analysis of 78 randomized clinical trials has shown an increase in all-cause mortality associated with supplementation with vitamin E, vitamin A, and B-carotene. No benefits or reductions in all-cause mortality were demonstrated for vitamin C or selenium (SOR A).

Question 9

159. A 42-year-old male has symptoms of hypogonadism. Which one of the following should be ordered first?

A) Early morning total serum testosterone

B) Early morning total and free serum testosterone

C) Early morning total and late afternoon total serum testosterone

D) Early morning and late afternoon free serum testosterone

E) Early morning and late afternoon total and free serum testosterone

Answer 9

ANSWER: A

The best initial test for the diagnosis of male hypogonadism is measurement of total testosterone in serum in a morning sample. Low concentrations of testosterone in serum should be confirmed by repeat measurement. If abnormalities in concentrations of sex hormone–binding globulin are suspected, measurement of free or bioavailable testosterone is indicated. Examples of conditions associated with altered sex hormone–binding globulin include liver disease, obesity, and diabetes mellitus.

Question 10

160. Which one of the following is the recommended first-line test for investigating suspected hyper- or hypothyroidism?

A) Free T3

B) Free T4

C) TSH

D) Antithyroglobulin

E) Antithyroid peroxidase

Answer 10

ANSWER: C

When investigating presumed hyper- or hypothyroidism, TSH is the first-line test (SOR A). If the patient is found to have an abnormal TSH level, free T4 is the next test to order. A free T3 test can also be helpful, but the free T4 assay is not affected by changes in iodothyronine-binding proteins, and T3 is often a peripheral product and can be abnormal due to nonthyroid diseases or medications. Occasionally, free T4 and T3 tests are performed as second-line tests, even if the TSH is normal, if the results do not match the clinical picture. Other second- and third-line tests include measurement of thyroid antibodies, such as antithyroid peroxidase and antithyroglobulin. Routine thyroid screening tests are not indicated for asymptomatic adults (SOR A).

Question 11

161. A 34-year-old G2P0101 at 11 weeks gestation comes to your office to establish care for her pregnancy. In reviewing her history you find that her first pregnancy was complicated by preeclampsia and she required induction of labor at 33 weeks. She also has chronic hypertension treated with chlorthalidone. Her blood pressure today is 128/78 mm Hg.

Which one of the following medications, if started today, will lower her risk of preeclampsia in this pregnancy?

A) Aspirin

B) Calcium

C) Labetalol

D) Nifedipine (Procardia)

E) Vitamin E

Answer 11

ANSWER: A

A 2013 update from the American College of Obstetricians and Gynecologists on hypertension in pregnancy summarizes the evidence regarding prevention of preeclampsia. The only medication with sufficient evidence to support its routine use is aspirin at dosages of 60–80 mg daily. In a high-risk population, defined as women with a history of preeclampsia in two or more pregnancies or a history of preeclampsia with delivery at less than 34 weeks, the risk of preeclampsia is sufficiently high to justify the use of aspirin, with a number needed to treat of 50 to prevent one case of preeclampsia. Calcium supplementation may help prevent preeclampsia in women with a very low calcium intake, but in the United States and other developed countries routine calcium supplementation has not been found to provide a benefit with regard to preeclampsia. Vitamin E has also been studied and found to be of no benefit. Antihypertensive agents such as labetalol and nifedipine may be used to control blood pressure in pregnant patients but they have not been shown to reduce the risk of preeclampsia.

Question 12

162. A 45-year-old female has ultrasonography of her kidneys as part of an evaluation for uncontrolled hypertension. The report notes an incidental finding of stones in the gallbladder, confirmed on right upper quadrant ultrasonography. She has no symptoms you can relate to the gallstones. Other than hypertension she has no chronic medical problems.

Which one of the following should you recommend to her at this time regarding the gallstones?

A) Expectant management

B) Oral dissolution therapy

C) Extracorporeal lithotripsy

D) Endoscopic retrograde cholangiopancreatography (ERCP)

E) Laparoscopic cholecystectomy

Answer 12

ANSWER: A

Most patients with asymptomatic gallstones can be managed expectantly with no treatment unless symptoms of biliary colic develop (SOR B). Only about 2% of such patients will develop symptoms. Once symptoms start, recurrence of pain, obstruction of the biliary or pancreatic duct, and the potential for attendant complications such as pancreatitis or ascending cholangitis become significantly more likely. In selected patients, oral dissolution therapy, ERCP, or lithotripsy may be effective alternative therapies, but laparoscopic cholecystectomy is clearly the treatment of choice for symptomatic cholelithiasis (SOR A).

Question 13

163. A mother brings her 7-year-old son in for a well child check and you find that their main concern is bedwetting. He has never achieved consistent nighttime continence. He currently wets the bed about 4 nights per week but has no difficulty maintaining continence during the day and reports no symptoms such as dysuria or urinary frequency. The parents have tried limiting his evening fluid intake but this has not helped. He is otherwise healthy. The patient wants to stop wearing nighttime diapers.

Which one of the following interventions has the best evidence of long-term success in addressing this condition?

A) A reward system for achieving dry nights

B) Use of a bed alarm

C) Desmopressin (DDAVP)

D) Imipramine (Tofranil)

E) Oxybutynin

Answer 13

ANSWER: B

This patient has primary monosymptomatic enuresis, the most common type of nocturnal enuresis. Primary refers to a child who has never achieved 6 months of continuous dry nights. Monosymptomatic refers to the absence of daytime symptoms such as dysuria or urinary frequency. Children with daytime urinary symptoms have a higher incidence of urinary tract pathology and require further diagnostic evaluation.

Primary monosymptomatic enuresis has a spontaneous annual remission rate of about 15% and does not require treatment unless the patient (not just the parent) is concerned about the issue. Treatment requires participation from both the child and the parents, so ensuring interest from both parties is key. Bed alarms have the best evidence for long-term success in that they train children via classical conditioning to awaken at the onset of urination and get up to finish voiding into the toilet.

Reward systems for achieving dry nights have some evidence of benefit but it is difficult to determine if they are superior to the spontaneous remission rate. Medications such as desmopressin, imipramine, and oxybutynin have a role in addressing nocturnal enuresis if bed alarm use is unsuccessful or if parents and children are not willing to engage in the activities necessary to implement the therapy. Medications may work well while they are used, but enuresis commonly recurs when they are stopped.

Question 14

164. A 55-year-old nonsmoking African-American female with diabetes mellitus sees you for a routine visit. She has no other cardiac risk factors. Her blood pressure is 120/74 mm Hg and she has a fasting total cholesterol level of 180 mg/dL, an HDL-cholesterol level of 52 mg/dL, and an LDL-cholesterol level of 100 mg/dL. Her calculated 10-year risk of atherosclerotic cardiovascular disease is 5.8%.

According to the 2013 American College of Cardiology/American Heart Association cholesterol guidelines, which one of the following is recommended for this patient?

A) No statin therapy

B) Low-intensity statin therapy

C) Moderate-intensity statin therapy

D) High-intensity statin therapy

Answer 14

ANSWER: C

The 2013 ACC/AHA cholesterol guidelines outline four major groups in whom statin therapy is beneficial: (1) individuals with clinical atherosclerotic cardiovascular disease (ASCVD), (2) those with primary elevations of LDL-C greater than 190 mg/dL, (3) patients age 40–75 with diabetes mellitus, an LDL-C level of 70–189 mg/dL, and no clinical ASCVD, (4) patients age 40–75 without clinical ASCVD or diabetes, an LDL-C level of 70–189 mg/dL, and an estimated 10-year ASCVD risk greater than 7.5%. For patients age 40–75 with diabetes, an LDL-C level of 70–189 mg/dL, and no clinical ASCVD, a moderate-intensity statin is recommended.

Question 15

165. A 65-year-old male with end-stage renal disease requires postoperative pain management. Which one of the following medications would be safest to use?

A) Fentanyl

B) Hydrocodone

C) Hydromorphone (Dilaudid)

D) Meperidine (Demerol)

E) Morphine

Answer 15

ANSWER: A

Fentanyl is one of the preferred narcotics in patients with end-stage renal disease. Fentanyl’s elimination is 99% hepatic and it has a long history of safe use in patients with renal failure. Morphine, hydromorphone, and hydrocodone can be used in these patients, but these drugs require close monitoring for side effects and indications for dosage reduction because they have active metabolites that accumulate in patients with renal failure. Meperidine, codeine, and propoxyphene are all contraindicated in chronic kidney disease because of the accumulation of toxic metabolites.

Question 16

166. A 30-year-old male presents with a 2-week history of swelling of the right posterior elbow. He recalls bumping his elbow against a door, but his pain quickly subsided. He began to notice the swelling over the next 2 days. On examination he has normal range of motion with a boggy, nontender mass over the olecranon.

Which one of the following would be most appropriate at this point?

A) A posterior splint

B) Aspiration

C) A corticosteroid injection

D) A uric acid level and erythrocyte sedimentation rate

E) A compression dressing

Answer 16

ANSWER: E

Aseptic olecranon bursitis is often preceded by minor trauma to the elbow followed by a nontender, boggy mass over the olecranon. Septic olecranon bursitis causes not just swelling, but also erythema, warmth, and pain. Half of affected individuals will have a fever. If septic bursitis is suspected, aspiration with bursal fluid analysis should be done and antibiotic therapy should be initiated. Aspiration is not recommended for the initial treatment of aseptic bursitis, as complications such as infection may occur. Management initially is with ice, compression dressings, and avoidance of activities that aggravate the problem. If conservative therapy is unsuccessful the problem can be managed by aspiration followed by compression dressings for 2 weeks. The bursa may be injected with a corticosteroid, but this could cause skin atrophy or infection. Surgical bursectomy can be offered for refractory cases lasting over 3 months.

Question 17

167. A 23-year-old female sees you for the first time for a routine health maintenance evaluation. She tells you that her father just had a “heart valve replacement” at age 47. On examination you note a harsh 3/6 systolic murmur at the right upper sternal border. She feels well and her exercise tolerance is normal. Her history indicates that she has been well throughout her life and received appropriate childhood vaccinations and care for routine illnesses. She denies tobacco, alcohol, and drug use now and in the past. Her blood pressure today is 132/84 mm Hg. You are concerned about aortic valve disease and order an echocardiogram for further evaluation.

Which one of the following is the most likely cause of aortic valve disease in this patient?

A) Hypertension

B) Endocarditis

C) Bicuspid aortic valve

D) Rheumatic heart disease

E) Coronary atherosclerosis

Answer 17

ANSWER: C

Bicuspid aortic valve is the most likely cause of heart valve disease in this family. It is the most common congenital heart defect in the United States, with a prevalence of approximately 1%–2%. This valve disorder appears to have a genetic basis, with an autosomal dominant pattern of inheritance and incomplete penetrance. The children of a patient with a bicuspid aortic valve have about a 10% chance of having this condition; it is therefore recommended to screen first degree relatives of affected patients with echocardiography. Most patients with a bicuspid aortic valve will eventually have significant aortic valve dysfunction (stenosis or insufficiency) and/or aortopathy such as aortic root dilation.

Rheumatic heart disease can also cause valve disease but its incidence is low in the United States, especially with appropriate treatment for streptococcal pharyngitis. Endocarditis is unlikely in the absence of systemic symptoms. Hypertension and coronary atherosclerosis are unlikely in this patient because of his normal blood pressure. These conditions also are more likely to cause obstructive coronary disease and heart failure than valve disease.

Question 18

168. A resting ankle-brachial index of 1.50 indicates which one of the following?

A) Normal circulation to a lower extremity

B) Borderline normal circulation which may not be problematic in an asymptomatic patient

C) Mild peripheral artery disease in a lower extremity

D) Severe peripheral artery disease in a lower extremity

E) Incompressible vessels in a lower extremity

Answer 18

ANSWER: E

An ankle-brachial index (ABI) is considered normal between 1.00 and 1.40, borderline from 0.91 to 0.99, and abnormal if less than or equal to 0.90. The lower the ABI, the more severe peripheral artery disease is likely to be. Values greater than 1.40 indicate incompressible vessels and are not reliable. Incompressible vessels may be found in patients with long-standing diabetes mellitus, or in older persons. A toe-brachial index measurement may be used in persons with incompressible arteries of the more proximal lower extremity.

Question 19

169. A 69-year-old male sees you for a routine evaluation. He has been in good health and takes no medication other than tamsulosin (Flomax) for symptoms of benign prostatic hyperplasia. He has never smoked. His blood pressure is 121/78 mm Hg, pulse rate 72 beats/min, and respiratory rate 18/min. His general physical examination is unremarkable, including cardiac and abdominal examinations. A digital rectal examination reveals mild enlargement of the prostate, without nodules.

According to the U.S. Preventive Services Task Force, this patient should be screened for

A) elder abuse

B) aortic aneurysm

C) multifactorial fall risk

D) dementia

E) hepatitis C

Answer 19

ANSWER: E

The U.S. Preventive Services Task Force recommends one-time screening for hepatitis C for individuals born between the years 1945 and 1965 (USPSTF B recommendation). As far as screening for the other problems listed, there is no significant evidence to determine whether this should be done on a widespread basis.

Question 20

170. Which one of the following has been shown to be effective for Lyme disease prophylaxis after removal of an engorged deer tick?

A) Amoxicillin

B) Ceftriaxone (Rocephin)

C) Cefuroxime axetil (Ceftin)

D) Doxycycline

E) Clarithromycin (Biaxin)

Answer 20

ANSWER: D

While all of the antibiotics listed have been used to treat Lyme disease, the only antibiotic that has been shown to be effective for chemoprophylaxis is doxycycline. A randomized, controlled trial showed that a single 200-mg dose of doxycycline was 87% effective for preventing Lyme disease if given within 72 hours after removal of a deer tick. Nevertheless, a meta-analysis showed that the number needed to treat to prevent one case of erythema migrans was 50, and routine prophylaxis is not recommended. It may be indicated, however, after removal of an engorged nymphal deer tick.

Question 21

171. A 58-year-old female sees you 3 days after she was clearing her sinuses with steam and burned her face. She developed small patches of dry, painful erythema without blisters on her chin, the left side of her mouth, and her left cheek. She had no difficulty breathing. She applied cold water to the burn and decided to self-treat initially but came in because she was experiencing some pain. Her injury is shown below.

She received Td vaccine last year. In addition to analgesics for pain control, which one of the following would be appropriate?

A) Cleaning the wound with povidone iodine (Betadine)

B) Covering the wound with an occlusive dressing

C) Applying aloe

D) Applying hydrocortisone 1% cream

E) Starting broad-spectrum antibiotics

Answer 21

ANSWER: C

Burns can be classified based on the depth and area of the burn. Only superficial and deep-thickness burns are included in the calculation of the burn area. Minor burns cover less than 10% of the body for patients 10–50 years old and less than 5% of the body for patients less than 10 or greater than 50 years old. Any burn involving the face, hands, or a major joint may be more complicated and should be promptly evaluated.

Superficial burns involve the epidermis and appear as painful patches of erythema and dry skin. Superficial partial-thickness burns involve part of the dermis and all of the epidermis. They cause painful blanching erythema with small blisters and weeping skin. This patient has a superficial burn but in a high-risk area.

Immediate management of a minor burn may include cooling with water but should not involve ice water as this may lead to further injury (SOR C). All wounds should be cleaned with sterile water but not a cleansing agent such as povidone iodine (SOR C). The skin should remain intact if possible and small blisters should not be debrided. Topical corticosteroids should be avoided, as they do not reduce inflammation.

Superficial burns do not require antibiotics or wound dressings. They can be treated with aloe vera, lotion, antibiotic ointment, or honey (SOR B). There is evidence that these treatments promote skin repair and prevent drying. Aloe vera may also decrease pain. There is also evidence that honey heals partial thickness wounds more quickly than conventional dressings.

Question 22

172. A 61-year-old female tells you that her brother was recently diagnosed with hereditary hemochromatosis and his physician suggested that she get tested. She feels well and has no significant health problems.

Which one of the following would be most appropriate for initial screening?

A) Serum transaminases

B) A CBC and a serum iron level

C) Testing for the HFE gene

D) Ferritin and transferrin saturation

E) Total iron binding capacity

Answer 22

ANSWER: D

The diagnosis of hereditary hemochromatosis requires a random measurement of serum ferritin and calculation of transferrin saturation. The transferrin saturation is calculated by dividing the serum iron level by the total iron binding capacity. If the serum ferritin level is elevated (greater than 200 ng/mL in women) or the transferrin saturation is greater than or equal to 45% the HFE gene should be checked. Measurement of liver transaminases plays a role in determining liver disease but is not helpful in the diagnosis.

Question 23

173. Complications of hypoparathyroidism include

A) somnolence

B) low vitamin D

C) muscle flaccidity

D) hyperkalemia

E) refractory heart failure

Answer 23

ANSWER: E

The classic symptoms of hypoparathyroidism are those of insufficient calcium. Typically these include refractory heart failure, tetany, seizures, altered mental status, and stridor. Refractory heart failure is related to the low calcium interfering with the normal contractility of myocytes. Low vitamin D can cause hypocalcemia but is not caused by it. Patients are not at risk for hyperkalemia if they have hypoparathyroidism. Seizures, not somnolence, and muscle twitching, not flaccidity, are symptoms of low calcium.

Question 24

174. A 42-year-old female presents to the emergency department with a 2-hour history of palpitations. Her physical examination is normal except for what seems to be a regular rhythm tachycardia and a blood pressure of 84/54 mm Hg. An EKG reveals a regular narrow-complex tachycardia at a rate of 180 beats/min without clear atrial activity.

The optimal treatment for this patient is

A) intravenous adenosine (Adenocard)

B) intravenous amiodarone (Cordarone)

C) intravenous diltiazem

D) intravenous verapamil

E) electrical cardioversion

Answer 24

ANSWER: A

Vagal maneuvers and administration of adenosine are useful in the diagnosis and treatment of narrow-complex supraventricular tachycardias. Adenosine, a very short-acting endogenous nucleotide that blocks atrioventricular nodal conduction, terminates nearly all atrioventricular nodal reentrant tachycardias and atrioventricular reciprocating tachycardias, as well as up to 80% of atrial tachycardias. Although intravenous verapamil and diltiazem, which also block the atrioventricular node, have a potential diagnostic and therapeutic use in narrow-complex tachycardia, they may cause hypotension and thus are not a first choice in the emergency setting. Electrical cardioversion is reserved for patients who do not respond to adenosine. Antiarrhythmic agents are rarely necessary in the early management of supraventricular tachycardias, with the exception of the management of arrhythmias that have caused hemodynamic instability and that have not responded to electrical cardioversion. In these cases, procainamide and ibutilide can be used.

Question 25

175. You see a 2-year-old African-American male for a well child check. He is a new patient and his examination is within normal limits except for an approximately 0.75-cm umbilical hernia that is easily reducible. The father states that the hernia has been present since birth, although he thinks it has grown slightly over the last year. The child does not seem to be bothered by the hernia and the father does not think it has ever become incarcerated.

Which one of the following should you do now?

A) Reassure and observe

B) Advise daily application of pressure dressings

C) Order an ultrasound examination

D) Refer for surgical repair

Answer 25

ANSWER: A

It is important to be able to tell children and their families that many small umbilical hernias resolve without surgical repair and that the rate of both incarceration prior to surgery and complications from surgery are very low. Surgical repair of pediatric umbilical hernias is indicated if the hernia has not resolved by 3–5 years of age or for incarcerated hernias at any age. The primary care physician may observe younger children who are asymptomatic, limiting the need for surgical referral. Smaller hernias (less than 1.0–1.5 cm in diameter) typically resolve more quickly than larger hernias. The surgery is usually done on an outpatient basis, which is often reassuring to parents. Less than 1% of patients experience incarceration. Imaging studies are not routinely required and applying pressure over the defect has no benefit.

Question 26

176. Which one of the following medications is associated with a higher risk of death due to stroke or sudden cardiac death in patients with dementia?

A) Diazepam (Valium)

B) Fluoxetine (Prozac)

C) Paroxetine (Paxil)

D) Quetiapine (Seroquel)

E) Venlafaxine

Answer 26

ANSWER: D

In April 2005 the FDA issued a boxed warning for second-generation antipsychotics, including quetiapine, after a meta-analysis demonstrated a 1.6- to 1.7-fold increase in the risk of death associated with their use in elderly patients with dementia, related in part to sudden cardiac death and also to stroke. In June 2008, after two large cohort studies showed a similar risk with first-generation antipsychotics, boxed warnings were added to this class as well. The other medications listed do not have this association or warning.

Question 27

177. A 65-year-old female is admitted to the hospital for a carotid endarterectomy and you are asked to make preoperative recommendations in advance of her surgery scheduled for tomorrow. She takes only low-dose aspirin. The physical examination is normal, including her blood pressure, as is an EKG. She has good exercise capacity and denies any symptoms of angina. You judge her to be stable for surgery.

Which one of the following should you recommend that the patient start today?

A) An ACE inhibitor

B) A B-blocker

C) A statin

D) A diuretic

Answer 27

ANSWER: C

If recommended prior to surgery, B-blockers should be started several weeks beforehand and carefully titrated. They may be harmful if initiated in the immediate perioperative period. Statins are recommended in the perioperative period for vascular surgery regardless of other cardiac risk factors; a statin would ideally have been initiated previously in this case, but may still be started in the immediate preprocedural period. There is no specific indication in this case for an ACE inhibitor.

Question 28

178. The intensely pruritic rash shown below is typical of

A) contact dermatitis

B) herpes simplex

C) pityriasis rosea

D) tinea corporis

Answer 28

ANSWER: A

Allergic contact dermatitis is secondary to a trigger that incites a delayed (type IV) hypersensitivity reaction. The most common sensitizers include plants (poison ivy, poison oak, and poison sumac), metals (nickel found in jewelry or belt buckles), and fragrances. Patch testing data has shown that out of 3700 known contact allergens, nickel caused contact dermatitis in 14.3% of patients, fragrance mix in 14%, neomycin in 11.6%, balsam of Peru in 10.4%, and thimerosal in 10.4%. The rash is limited to the area of exposure and is characterized by an intensely pruritic papular eruption with erythema. Herpes simplex is characterized by a vesicular eruption surrounded by erythema and associated with localized burning and tingling. Tinea corporis presents as a pruritic circular or oval erythematous lesion with superficial scaling and erythema. Multiple oval or circular pruritic salmon-colored scaly lesions preceded by a herald patch are typical of pityriasis rosea (SOR C).

Question 29

179. A 76-year-old male completed chemotherapy for carcinoma of the pancreas 3 months ago. He was seen 6 weeks ago by his oncologist and thought to be in remission. He presents to your office today with a 2-week history of malaise and epigastric pain. You perform an examination that indicates a possible epigastric mass.

Elevation of which one of the following laboratory studies would suggest recurrent pancreatic cancer?

A) A1-Antitrypsin

B) A-Fetoprotein

C) Serum amylase

D) CA 19-9

E) CA-125

Answer 29

ANSWER: D

The most common serum tumor marker used for pancreatic ductal adenocarcinoma is cancer antigen 19-9, which is expressed in pancreatic and hepatobiliary disease. In symptomatic patients it can help confirm the diagnosis and aid in assessing the prognosis and predicting the likelihood of recurrence after resection.

CA-125 may be a useful marker with ovarian carcinoma, and A-fetoprotein may be followed as a marker of hepatoma. Neither serum amylase nor A-1-antitrypsin is useful as a tumor marker.

Question 30

180. The most common source of chest pain in children is

A) pulmonary

B) cardiac

C) musculoskeletal

D) gastroesophageal

E) psychogenic

Answer 30

ANSWER: C

Chest pain is a common presenting complaint in children and certainly can result from serious cardiac pathology. However, the majority of chest pain in children is benign, and determining clinically which patients need a cardiac workup is therefore paramount. Patients and families overestimate the prevalence of cardiac causes of chest pain and underestimate the prevalence of more benign causes. The most common cause of chest pain in children is musculoskeletal (50%–60%) followed by psychogenic (10%–30%) and respiratory causes (3%–12%). Cardiac conditions account for 0%–5% of cases of chest pain in children. Red flags that suggest a cardiac etiology include a patient history of palpitations with the chest pain, an abnormal cardiac physical examination (rubs or gallops), exertional chest pain without another more likely etiology such as asthma, and a positive family history. When any of the red flags is present, the patient should be referred to a pediatric cardiologist. This patient has no red flags and the most likely etiology of her chest pain is therefore musculoskeletal.

Question 31

181. A 59-year-old male is being evaluated for a 2-day history of intermittent “heart fluttering.” He reports that he has had high blood pressure for several years and has been reluctant to start treatment for it. His EKG is shown below.

Which one of the following laboratory tests is most likely to be abnormal in this patient?

A) D-dimer

B) Potassium

C) Troponin

D) TSH

Answer 31

ANSWER: C

The patient has EKG findings suggestive of an acute ST-elevation myocardial infarction. This is demonstrated on the EKG by the presence of ST-segment elevation in contiguous leads I, aVL, and V6. Troponin, a cardiac biomarker released from damaged myocardial cells, is elevated in patients with an acute myocardial infarction. Elevated D-dimer suggests thromboembolism, but normal levels have a high negative predictive value for ruling out pulmonary embolism. Hyperkalemia is associated with peaked T-waves in multiple leads. EKG findings in patients with a pulmonary embolism include sinus tachycardia with an S1Q3T3 pattern (T-wave inversion in III), incomplete right bundle branch block, and right precordial T-wave inversions. Thyroid hormone abnormalities can be associated with nonspecific EKG findings, but tachyarrhythmias (including atrial fibrillation) are more common in hyperthyroidism, whereas bradycardia is more common in hypothyroidism (SOR C).

Question 32

182. An asymptomatic 60-year-old male sees you for a health maintenance visit. His past medical history is significant for hypertension and hyperlipidemia. His medications include chlorthalidone, 25 mg daily, and atorvastatin (Lipitor), 20 mg daily. He smoked 2 packs of cigarettes a day for 20 years but quit 5 years ago. The physical examination is normal. Laboratory findings include a normal basic metabolic panel, a cholesterol level of 210 mg/dL, an HDL-cholesterol level of 34 mg/dL, an LDL-cholesterol level of 150 mg/dL, and a triglyceride level of 200 mg/dL.

Which one of the following screening tests is recommended by the U.S. Preventive Services Task Force for this patient?

A) Prostate-specific antigen (PSA)

B) A bone density test

C) Abdominal ultrasonography

D) Low-dose chest CT

E) Carotid ultrasonography

Answer 32

ANSWER: D

The U.S. Preventive Services Task Force (USPSTF) recommends screening smokers for lung cancer with low-dose CT. Patients should be age 55–80 and healthy. They should be current smokers or have quit within the past 15 years, and have a 30-pack-year history of smoking. The screening test is low-dose CT of the chest. Abdominal ultrasonography to screen for abdominal aneurysms is recommended for any male age 65–75 who has ever smoked (USPSTF B recommendation). A bone density test screens for osteoporosis and is recommended for women age 65 or older or in younger women at increased risk. The USPSTF recommends against PSA testing (D recommendation) for prostate cancer, as well as screening for carotid artery stenosis.

Question 33

183. A 63-year-old female with community-acquired pneumonia is being treated with appropriate antibiotics. The only abnormality on a basic metabolic panel is a serum sodium level of 121 mEq/L (N 135–145). She reports that her shortness of breath and cough are improving. She has no other complaints on a review of systems.

On examination the patient is noted to have normal vital signs and mucous membranes are moist. She has crackles in her right lower lobe. Skin turgor is normal. The remainder of the physical examination is normal. Further testing reveals the following:

Urine sodium. . . . . . . . . . . . 50mEq/L

Serum osmolality . . . . . . . . 276 mOsm/kg (N 280–285)

Urine osmolality . . . . . . . . . 300 mOsm/kg

Which one of the following would be most appropriate at this point?

A) Intravenous diuretics

B) Intravenous hypertonic saline

C) Intravenous isotonic saline

D) Fluid restriction

E) No further interventions

Answer 33

ANSWER: D

This patient has hypotonic hyponatremia, manifested by low serum osmolality. She is asymptomatic and has no signs of hypovolemia on her laboratory tests or physical examination. Her urine sodium is high and her urine osmolality is low, which indicates the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). This is most likely related to her pneumonia, which is improving. The initial treatment for mild euvolemic hyponatremia is fluid restriction. Intravenous isotonic saline would be indicated for mild hypovolemic hyponatremia. Intravenous hypertonic saline would be indicated for severe hyponatremia with symptoms. Intravenous diuretics would be indicated for hypervolemic hyponatremia, such as in heart failure, along with fluid and sodium restriction.

Question 34

184. A 53-year-old female without risk factors for colorectal cancer undergoes a screening colonoscopy. A high-quality examination reveals five 3- to 7-mm sessile polyps in the sigmoid and rectal areas. Biopsy results show that they are hyperplastic polyps. No other abnormalities are noted.

When should this patient have her next colonoscopy?

A) 1 year

B) 3 years

C) 5 years

D) 10 years

E) No further colonoscopies are needed

Answer 34

ANSWER: D

Hyperplastic polyps less than 10 mm in size in the rectum and sigmoid colon carry a low risk for developing into colon cancer. If they are the only finding, colonoscopy may be repeated in 10 years.

Question 35

185. Screening for chronic hepatitis B infection is NOT recommended for which one of the following?

A) Patients on chronic immunosuppressive therapy

B) Patients with end-stage renal disease who are on hemodialysis

C) Household contacts of individuals with chronic hepatitis B

D) Pregnant women with no risk factors for hepatitis B

E) All newborns

Answer 35

ANSWER: E

Worldwide, hepatitis B is a common cause of liver failure, cirrhosis, and hepatocellular carcinoma. The disease characteristically is asymptomatic before such complications develop. Although routine infant vaccination against hepatitis B has greatly decreased the incidence of this infection in the United States, it remains a significant cause of morbidity and mortality both in the United States and globally. Identifying persons infected with hepatitis B allows vaccination of their household contacts and sexual partners, thereby preventing further transmission. It also allows for medical treatment of infected individuals, including antiviral therapy and monitoring for the development of cirrhosis or hepatocellular carcinoma.

The CDC recommends screening for hepatitis B in patients on hemodialysis, household contacts of individuals with chronic hepatitis B, patients on immunosuppressive therapy, and all pregnant women. Other individuals who should be screened include anyone exposed to bodily fluids of infected individuals, such as sexual partners or infants of infected mothers. Behavioral risks such as intravenous drug use are also an indication for screening. Patients from areas where HBsAg prevalence is greater than 2% should also be screened.

Question 36

186. A 67-year-old male with moderate macrocytosis complains of paresthesias of his feet. If the patient has a borderline low vitamin B12 level, elevated levels of which one of the following would suggest vitamin B12 deficiency?

A) Serum gastrin

B) Reticulocytes

C) Methylmalonic acid

D) Serum ferritin

E) Serum folate

Answer 36

ANSWER: C

Neurologic symptoms may develop with low-normal vitamin B12 levels in serum. In true vitamin B12 deficiency, methylmalonic acid and homocysteine levels are typically quite elevated, and these return to normal with treatment. Gastrin levels may be abnormal in pernicious anemia, but are not diagnostic alone. High ferritin levels are seen with increased iron stores in the liver, and ferritin levels are used to screen for hemochromatosis.

Question 37

187. In the United States the most common form of child abuse is

A) physical abuse

B) emotional abuse

C) sexual abuse

D) neglect

Answer 37

ANSWER: D

Neglect is the most common form of child abuse and is the most common type of abuse in children who die as a result of abuse. In 2011, 79% of abused children suffered from neglect, 18% from physical abuse, and 9% from sexual abuse. Among abused children who died, 71% suffered from neglect, 48% from physical abuse, and less than 1% from sexual abuse. Neglect is defined as the failure of caregivers to provide needed, age-appropriate care, even though the caregiver was financially able to do so or was offered financial or other assistance to provide appropriate care.

Question 38

188. A 65-year-old female presents to the emergency department as directed by her primary care physician because of “high potassium” that was found today during routine laboratory monitoring. The patient has a past medical history significant for diet-controlled diabetes mellitus, hypertension, and asthma. She feels well and specifically denies palpitations, fatigue, changes in urine output, and muscle cramps. You do not have access to the patient’s outpatient medical records and order a chemistry panel in the emergency department with the following results:

Sodium………………………. 143mEq/L(N135–145) Potassium………………….. 6.3mEq/L(N3.5–5.0) CO2……………………………. 27 mEq/L (N 22–30) Creatinine………………….. 1.6mg/dL(N0.6–1.0) BUN……………………………. 30mg/dL(N7–21)

Which one of the following is the first additional test that should be obtained in the diagnostic evaluation of this patient?

A) A urinalysis

B) A CBC

C) Arterial blood gases

D) An EKG

E) Renal ultrasonography

Answer 38

ANSWER: D

Because hyperkalemia can have deleterious effects on the myocardium, an EKG is the first diagnostic test in the workup of a patient with hyperkalemia. Although not all patients with hyperkalemia will have an abnormal EKG, those who do need to be given intravenous calcium immediately to prevent arrhythmias and cardiac arrest. A urinalysis, blood pH, and CBC are part of the workup to determine the etiology of the hyperkalemia, but an EKG is the top priority. There is not a defined threshold for treatment of hyperkalemia with intravenous calcium in asymptomatic patients without EKG changes. Likewise, renal ultrasonography may be indicated for other reasons but is not part of the initial workup for hyperkalemia.

Question 39

189. A 58-year-old male delivery truck driver is diagnosed with type 2 diabetes mellitus and after several months of working on lifestyle modification his hemoglobin A1c is 8.0%. You suggest it is time to start a medication to help control his condition but he is very worried about having a “low sugar reaction” that would prevent him from driving. He is on no other medications at this time. His only other health problem is long-standing controlled hypertension. His BMI is 33.1 kg/m2 and his serum creatinine level is 1.2 mg/dL (N 0.6–1.5).

Which one of the following medications would be least likely to cause hypoglycemia in this patient?

A) Canagliflozin (Invokana)

B) Glimepiride (Amaryl)

C) Glipizide (Glucotrol)

D) Insulin glargine (Lantus)

E) Metformin (Glucophage)

Answer 39

ANSWER: E

Metformin is an inexpensive first-line oral agent for type 2 diabetes mellitus. Its mechanism of action is to increase the sensitivity of the liver and peripheral tissues to insulin. This assists the patient with weight loss efforts and, unlike insulin secretagogues, has been proven to reduce mortality with long-term use. When metformin is used as monotherapy it is not associated with episodes of hypoglycemia. For many years there has been a concern that metformin can increase the risk for lactic acidosis. This risk has been assumed to be greater in conditions that can lead to tissue hypoperfusion, such as heart failure or hypovolemia, or with renal impairment. The FDA has historically recommended against the use of metformin for any patient with even mild renal impairment (creatinine greater than 1.4 mg/dL for women and greater than 1.5 mg/dL for men). However, a recent meta-analysis did not find supportive evidence for such restrictions. Newer evidence suggests that the use of metformin is safe even with mild to moderate renal impairment (eGFR greater than 30 mL/min) (SOR A).

Question 40

190. The most common carcinoma diagnosed in the United States is

A) colon adenocarcinoma

B) prostate carcinoma

C) breast carcinoma

D) basal cell carcinoma

E) malignant melanoma

Answer 40

ANSWER: D

Approximately 1.7 million breast, colon, prostate, and other carcinomas are diagnosed in the United States each year. More than 2.5 million basal cell carcinomas will be diagnosed. Most of these will be treated, including more than 100,000 in the patient’s last year of life. These are very slow growing tumors that rarely metastasize, and asymptomatic basal cell carcinomas rarely need treatment in frail older patients.

Question 41

191. The parents of a 5-year-old male bring him in for evaluation of likely attention deficit/hyperactivity disorder. You have suspected this diagnosis for some time, and the parents have brought in surveys filled out by themselves and the child’s kindergarten teacher which confirm your suspicions.

The most appropriate initial treatment is

A) behavioral therapy

B) A2-receptor agonists such as guanfacine (Intuniv, Tenex)

C) psychostimulants such as methylphenidate (Ritalin)

D) atomoxetine (Strattera)

Answer 41

ANSWER: A

Behavioral therapy should be the primary treatment for attention-deficit/hyperactivity disorder (ADHD) in children younger than 6 years, and it may be helpful at older ages (SOR B). Treatment of ADHD in children 6 years and older should start with medication (SOR B).

Question 42

192. Which one of the following is most characteristic of hoarding disorder?

A) Collecting eccentric or bizarre items

B) Collecting only seemingly worthless items

C) Deriving pleasure from collected items

D) Anxiety and emotional distress if collected items are disposed of

Answer 42

ANSWER: D

Hoarding disorder is included in the DSM-5. It is more common than previously realized, affecting between 2% and 6% of adults. It is characterized by excessive, often dangerous, clutter and disorganized living spaces. The items collected or saved often are worthless, such as old newspapers and paperwork, but may also be valuable items. Opposed to this is normal collecting, which is organized and pleasurable, and does not lead to dangerous or chaotic living spaces. Both could involve collecting unusual or seemingly bizarre items. However, with hoarders, disposing of the items causes extreme anxiety and emotional distress.

Question 43

193. A 24-year-old female presents with a painless ulcer on her labia, which has been present for a week. You suspect primary syphilis, but a rapid plasma reagin (RPR) test is negative.

Which one of the following is the best strategy for confirming or ruling out syphilis in this situation?

A) A spinal fluid analysis

B) A serum fluorescent treponemal antibody absorption (FTA-ABS) test now

C) A Treponema pallidum particle agglutination (TPPA) test now

D) A Venereal Disease Research Laboratory (VDRL) test now

E) Repeating the RPR test in 2 weeks

Answer 43

ANSWER: E

A nontreponemal test, such as the rapid plasma reagin (RPR) test or Venereal Disease Research Laboratory (VDRL) test, is the initial step for evaluating a patient with suspected syphilis. These tests become positive within 3 weeks of the appearance of the primary chancre, so they may be negative in patients with an early infection. Darkfield microscopy of material obtained from a swab of the lesion is often useful in this situation, but it requires special equipment and experienced technicians. If there is a strong suspicion of syphilis, a repeat nontreponemal test in 2 weeks is indicated. Patients with a positive nontreponemal test should be tested with a specific treponemal test for confirmation. These tests may lack reactivity in early primary syphilis, however, and are not indicated for use in the initial evaluation. Spinal fluid analysis is used only for the evaluation of tertiary syphilis.

Question 44

194. A 53-year-old female with a past medical history of hypertension and high cholesterol presents to discuss options for tobacco cessation. She has a 30-pack-year history of smoking and currently smokes between 1 and 11⁄2 packs per day. She tried varenicline (Chantix) but had nightmares while she was using it and does not want to try it again. Many of her family members have seizure disorders and she is therefore hesitant to try bupropion (Wellbutrin). She has used nicotine patches with minimal success.

Which one of the following pharmacotherapies would be most likely to help in her effort to stop smoking?

A) Fluoxetine (Prozac)

B) Naltrexone (ReVia)

C) Nortriptyline (Pamelor)

D) Selegiline (Eldepryl)

E) St. John’s wort

Answer 44

ANSWER: C

Trials have evaluated various antidepressant medications as aids in tobacco cessation. Both bupropion and nortriptyline have been found to increase smoking cessation success rates. Because this patient does not want to try bupropion, nortriptyline would be a reasonable option. Studies have shown similar efficacy for these two medications, although there is a lack of evidence for increased efficacy when these medications are added to nicotine replacement therapy. Studies have not shown a benefit for promoting tobacco cessation with SSRIs such as fluoxetine, monoamine oxidase inhibitors such as selegiline, opioid antagonists such as naltrexone, or St. John’s wort.

Question 45

195. The specificity of a screening test is best described as the proportion of persons

A) with the condition who test positive

B) with the condition who test negative

C) with the condition who test positive, compared to the total number screened

D) without the condition who test positive

E) without the condition who test negative

Answer 45

ANSWER: E

A screening test’s specificity is the proportion of persons without the condition who test negative for that condition. In other words, it is a measure of the test’s ability to properly identify those who do not have the disease. Conversely, the sensitivity of a screening test is the proportion of those with the condition who test positive. The other options listed describe false-negatives, false-positives, and prevalence.

Question 46

196. An 18-month-old previously healthy infant is admitted to the hospital with bronchiolitis. Pulse oximetry on admission is 92% on room air.

Which one of the following should be included in the management of this patient?

A) Tracheal suction to clear the lower airways

B) Nasal suction to clear the upper airway

C) Chest physiotherapy

D) Corticosteroids

E) Azithromycin (Zithromax)

Answer 46

ANSWER: B

Recommendations for the treatment of hospitalized infants with bronchiolitis include nasal suctioning via bulb or neosucker to clear the upper airway. Deep suction (beyond the nasopharynx) is not recommended. Oxygen is recommended for infants with a persistent oxygen saturation less than 90%. Bronchodilators should not be used routinely in the management of bronchiolitis, and corticosteroids, antibiotics, nasal decongestants, and chest physiotherapy are not recommended. A single trial of inhaled epinephrine or albuterol for respiratory distress may be considered, but only if there is a history of asthma, atopy, or allergy.

Question 47

197. Which one of the following is associated with bisphosphonate use for the treatment of osteoporosis?

A) Hypercalcemia

B) Hyperphosphatemia

C) Vitamin D deficiency

D) Atypical femoral shaft fractures

E) Renal failure

Answer 47

ANSWER: D

The use of bisphosphonates is associated with a small increase in the risk of atypical femoral shaft fractures. The risk increases with the duration of use (SOR B). These drugs are also associated with an increased risk of osteonecrosis of the jaw, esophagitis, and esophageal ulceration, as well as hypocalcemia. In fact, bisphosphonates are used as a treatment for hypercalcemia. They do not affect phosphorus or vitamin D levels.

Question 48

198. A 20-year-old male college student comes to the emergency department in January acutely short of breath and looking very ill, with tachypnea, tachycardia, nausea, and a headache. Pulse oximetry shows an oxygen saturation of 100% on room air, and arterial blood gas measurement shows a PaO2 of 95 mm Hg.

Of the following, which one is the most likely diagnosis?

A) Carbon monoxide poisoning

B) Adult respiratory distress syndrome

C) Methemoglobinemia

D) Lobar pneumonia

E) Viral pneumonia

Answer 48

ANSWER: A

Carbon monoxide (CO) exposure most commonly results from fuel combustion in heaters, stoves, or automobiles, so it is most often seen during cold periods when people are in closed quarters. Symptoms include headache, nausea, vomiting, and weakness, and patients have a flushed complexion, so symptoms are commonly attributed to viral flu-like illnesses. CO poisoning results in the formation of carboxyhemoglobin, which does not carry oxygen. All oxygen-carrying sites are occupied by CO, which has such a high affinity for hemoglobin that oxygen cannot displace it. If a patient has a carboxyhemoglobin level of 25%, and their hemoglobin level is 12 mg/dL, their effective hemoglobin level is only 9 mg/dL since 25% of their hemoglobin is not carrying oxygen. If the carboxyhemoglobin level is 25%, then the maximum oxygen saturation that can be attained is 75%. However, a pulse oximeter will show an oxygen saturation of 100% because the color of carboxyhemoglobin is bright red, which is what the pulse oximeter is detecting. Thus, pulse oximetry is not reliable in patients with CO poisoning.

Similarly, arterial blood gas measurements are based on oxygen gas tension (pO2) and not oxygen content or true oxygen saturation. The only arterial blood gas abnormality in CO poisoning may be metabolic acidosis, which is a consequence of inadequate oxygen delivery to the peripheral tissues. This causes an anaerobic metabolism and lactic acid production, but is not seen early in CO poisoning. Serious cases of pneumonia, ARDS, or methemoglobinemia would produce abnormalities on pulse oximetry or arterial blood gas measurements. To detect CO poisoning it would be necessary to order either a CO level or a co-oximetry test.

Question 49

199. A 25-year-old gravida 1 para 1 presents for insertion of a levonorgestrel-releasing intrauterine device (Mirena). She is on the last day of her menses, which began 5 days ago. A urine pregnancy test in the office is negative. You insert the device without complications and she asks how long she needs to use backup contraception.

Which one of the following would be the most appropriate advice?

A) Backup contraception is not necessary

B) She should use backup contraception for the next 48 hours

C) She should use backup contraception for the next 7 days

D) She should use backup contraception for the next 14 days

E) She should use backup contraception for the next month

Answer 49

ANSWER: A

The Centers for Disease Control and Prevention (CDC) provides specific recommendations for backup contraception after IUD insertion. According to the CDC guidelines, this patient does not need to use backup contraception if her IUD is inserted today because it was inserted within 7 days after menstrual bleeding started. If the levonorgestrel IUD is inserted more than 7 days after menstrual bleeding starts, the patient needs to abstain from sexual intercourse or use additional contraceptive protection for the next 7 days.

Question 50

200. Which one of the following classes of diabetes medications increases the risk of genitourinary infections by blocking glucose reabsorption by the kidneys?

A) SGLT2 inhibitors such as canagliflozin (Invokana)

B) GLP-1 receptor agonists such as exenatide (Byetta)

C) DPP-4 inhibitors such as sitagliptin (Januvia)

D) Meglitinides such as repaglinide (Prandin)

E) A-Glucosidase inhibitors such as acarbose (Precose)

Answer 50

ANSWER: A

SGLT2 inhibitors inhibit SGLT2 in the proximal nephron. This blocks glucose reabsorption by the kidney, increasing glucosuria. The advantages of this medication include no hypoglycemia, decreased weight, decreased blood pressure, and effectiveness at all stages of type 2 diabetes mellitus. Disadvantages are that it increases the risk of genitourinary infections, polyuria, and volume depletion and increases LDL-cholesterol and creatinine levels. GLP-1 receptor agonists work by activating the GLP-1 receptors, causing an increase in insulin secretion, a decrease in glucagon secretion, slowing of gastric emptying, and increasing satiety. DPP-4 inhibitors inhibit DPP-4 activity, which increases postprandial active incretin concentration. This increases insulin secretion and decreases glucagon secretion. Meglitinides act by closing the ATP-sensitive K+ channels on the B-cell plasma membranes, which increases insulin secretion. A-Glucosidase inhibitors inhibit intestinal A-glucosidase, which slows intestinal carbohydrate digestion and absorption.