USMLE USMLE-STEP-2 Online Practice Questions and Exam Preparation

USMLE USMLE-STEP-2 Online Questions & Answers

• Question 651:

  A 20-year-old asymptomatic college student presents to your clinic for contraception. She states that she has been sexually active for 2 years with one partner, and that they usually use condoms. Along with a Papanicolaou (Pap) smear and pelvic examination, which of the following should you also recommend?

  A. self-breast examination
  B. screening for chlamydia
  C. screening for syphilis
  D. thyroid-stimulating hormone (TSH) test
  E. screening for gonorrhea
  B. screening for chlamydia

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  Explanation

  The USPSTF strongly recommends that clinicians routinely screen all sexually active women aged 25 years and younger, and other asymptomatic women at increased risk for infection, for chlamydial infection.

• Question 652:

  A45-year-old woman has bilateral breast pain that is most severe premenstrually. On palpation, there is excessive nodularity, tenderness, and cystic areas that diminish in size after menses. Which of the following is the most likely diagnosis?

  A. fibrocystic disease
  B. fibroadenomas
  C. intraductal papilloma
  D. breast cancer
  E. engorgement attributable to increased prolactin
  A. fibrocystic disease

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  Explanation

  The classic symptom of fibrocystic breast disease is cyclic bilateral breast pain. The pain and associated diffuse breast engorgement is most severe premenstrually. Cystic changes palpated premenstrually typically are smaller postmenstrually. Fibroadenomas are firm, rubbery, freely mobile, solid, and usually solitary masses. Intraductal papilloma does not cause diffuse breast symptoms. Spontaneous and intermittent nipple discharge is the classic sign of an intraductal papilloma. Intraductal carcinoma is more likely if there is a discharge from multiple ducts. Breast cancer should be suspected when a solitary firm nodule does not change throughout the menstrual cycle. A mammogram is helpful, but any suspicious mass should be biopsied. Hyperprolactinemia can cause breast engorgement, but the pain is usually mild, and cystic areas tend not to vary in size

• Question 653:

  The following questions identify health care planning methods used by various organizations. The answer options are strategies that may correspond to these methods. Select the strategy that best corresponds to each health care planning method.

  A local health department employs population based planning in meeting the needs of its community.

  A. identifying what the market for services are and estimating future demands
  B. identifying mechanisms for carrying out established goals within specific program areas
  C. identifying financial resources to meet community needs
  D. identifying barriers to growth and the resources needed to overcome them
  A. identifying what the market for services are and estimating future demands

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  Explanation

  Local health departments make plans for the entire population in the jurisdiction for which they have responsibility, whether it is a single county, city, or multicounty health department. Their planning is population based. This involves estimating health requirements, matching them with existing resources, and outlining a health strategy based on the deficit or surplus demonstrated.

• Question 654:

  A 35-year-old pharmacist complains of "hurting all over." Her pain is particularly bad in her upper back and shoulders, and she notes morning stiffness. On examination, her joints are not inflamed, but she has symmetric "tender points" in the posterior neck, anterior chest, lateral buttocks, medial knees, and lateral elbows. You make a preliminary diagnosis of fibromyalgia. Which of the following is another characteristic symptom associated with this syndrome?

  A. sleep disturbance
  B. fever
  C. rash on the extremities
  D. muscle weakness
  E. migratory joint inflammation
  A. sleep disturbance

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  Explanation

  Sleep disturbance is a characteristic symptom associated with fibromyalgia. Patients awaken feeling tired. The examination, other than tenderness in 14 specific, symmetrical points, is usually normal. Fever, rash on the extremities, muscle weakness, and migratory joint inflammation point to Lyme disease or other rheumatologic disorders. Asedimentation rate should be normal. If elevated, it may point to another diagnosis. Lyme titers are not indicated unless the patient has symptoms or history suggestive of the disease. Electromyelography and spine radiographs are typically normal and unnecessary for help in establishing the diagnosis.

  Depression can be associated with pain, but screening for it early on does not make sense and might offend the patient. Low-dose antidepressants often help to correct the sleep pattern and result in relief of pain. Nonsteroidal anti-inflammatory agents can also be used as needed; low-dose steroid is not indicated. Exercise is also helpful, and patients should be encouraged to stay physically active. Amoxicillin is not used for fibromyalgia. Benzodiazepines have addictive potential and lose their effectiveness

  for sleep after a few weeks.

• Question 655:

  Little sedation, strong serotonin, and norepinephrine effect. Match the antidepressants below with the effect described.

  A. amitriptyline
  B. nefazodone
  C. citalopram
  D. phenelzine
  E. duloxetine
  E. duloxetine

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  Explanation

  The drugs listed in this question are examples of the various classes of antidepressants. These classes include the tricyclics, the SSRIs, the MAOIs, the triazolopyridines, and the serotonin-norepinephrine reuptake inhibitors. Understanding the site of action, neurotransmitter( s) involved, and side effects characteristic of these classes is helpful in selecting an antidepressant for a particular patient. SSRIs that are comparable in their antidepressant effects to the older tricyclics but significantly safer when taken in larger doses, as in suicidal overdose, are frequently used as the first choice in the treatment of depression. An example here is citalopram. Drugs that both inhibit serotonin reuptake and block 5-HT2 receptors are characteristic of the triazolopyridines. The overall effect of these actions is believed to decrease both depression and anxiety in patients. There are two drugs in this class: trazodone and nefazodone. Strong sedation caused by histaminergic and anticholinergic activity is seen in the older antidepressants--the tricyclics. These also have both serotonin and norepinephrine effects that are important in decreasing depression. Amitriptyline is the drug example listed here.

  Drugs demonstrating little sedation and significant serotonin, norepinephrine, and dopamine effects are more characteristic of the serotoninnorepinephrine reuptake inhibitors. They are effective in managing depression because there is no antihistaminergic activity and little sedation is seen. Duloxetine and Venlafaxine are examples. MAOIs increase the concentrations of serotonin, norepinephrine, and dopamine by inhibiting their degradation. The MAOIs, although effective as antidepressants, are used relatively infrequently because of the potential development of a hypertensive crisis induced by consuming tyramine- containing foods while on the MAOI. An example here is phenelzine.

• Question 656:

  A 42-year-old man admitted with a high fever and leukocytosis is transferred to the intensive care unit in shock. Which of the following is a common finding in the early stages of septic shock?

  Which of the following is an appropriate initial therapy for both septic shock and cardiogenic shock?

  A. prophylactic antibiotics
  B. beta blockers
  C. volume resuscitation with crystalloid fluids
  D. mechanical ventilation
  E. diuretics
  C. volume resuscitation with crystalloid fluids

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  Explanation

  The usual early hemodynamic response to sepsis is a hyperdynamic circulation. This includes tachycardia, elevated cardiac output, and decreased systemic resistance. Septic shock may then progress with intractable hypotension, metabolic acidosis, reduced cardiac output, oliguria, and death. The initial resuscitation of patients with all forms of shock requires rapid expansion of circulating blood volume to help maintain BP and tissue perfusion. This is usually achieved with the infusion of crystalloid fluids.

  When septic shock is suspected, cultures of blood, urine, and other sources along with antibiotic therapy targeted toward the most likely source is critical. Mechanical ventilation may be required when altered mental status, acidosis, and hypoxia are present. Beta-blockers and diuretics may have specific indications that cardiac ischemia and pulmonary edema are present

• Question 657:

  You receive a call from the parents of a 1 year old who is due for his well-child visit next week. They have just received a letter from their daycare center that an employee has hepatitis A. Which of the following is the best treatment plan?

  A. Give hepatitis A immune globulin and hepatitis A vaccine.
  B. Treat with hepatitis A immune globulin.
  C. Obtain hepatitis A serology and give hepatitis A vaccine.
  D. Give hepatitis A vaccine.
  E. No treatment is needed.
  A. Give hepatitis A immune globulin and hepatitis A vaccine.

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  Explanation

  Children, especially those in daycare, commonly are infected with the hepatitis A virus.Unlike adults, children most often are asymptomatic. Frequently, outbreaks of hepatitis A in a daycare center are not recognized until a daycare worker or parent of an attendee becomes ill. Immunization against hepatitis A virus is now routinely recommended because of this. After exposure both immune globulin and vaccine should be given to the unvaccinated individual.

• Question 658:

  A 55-year-old woman has a bloody discharge from her left breast. A mammogram discloses a cluster of microcalcifications 3 cm beneath her left nipple.

  Which of the following is the best predictor of survival after appropriate treatment of breast cancer?

  A. an initial tumor 1.5 cm or smaller in diameter
  B. the presence of estrogen receptors
  C. the presence of progesterone receptors
  D. a well-differentiated tumor
  E. axillary nodes negative for cancer
  A. an initial tumor 1.5 cm or smaller in diameter

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  Explanation

  In women with a primary tumor of 11.5 cm or less, the recurrence risk is approximately 15%, primarily because the likelihood of complete excision is greatest. Women with positive sex- steroid receptors in the tumor also have a better prognosis for several reasons: the tumor tends to be better differentiated, and 5- year therapy with tamoxifen significantly reduces recurrence. Although survival decreases as the number of positive axillary lymph nodes increases, the role of sentinel lymph node biopsy and axillary lymphadenectomy has become controversial. There appears to be a trend against axillary lymphadenectomy, especially with ductal carcinoma in situ less than 1.5 cm diameter.

• Question 659:

  You are examining the relationship between hypertension and myocardial infarction (MI) in your community. In order to do so, you send a questionnaire to the whole population in your community (1000 persons). All 1000 persons responded. The results obtained from that questionnaire are presented below in table.

  

  You randomly select a sample of 100 questionnaires in order to determine how representative your results would have been compared to the whole population if you had originally only sampled 100 individuals from your community. The results obtained are shown below in table.

  

  Which of the following statistical tests could best be used to determine whether there is a significant increase in the history of MI among those persons who have hypertension in comparison with those without hypertension?

  A. t-test, single-tailed
  B. t-test, two-tailed
  C. test of variance
  D. P value
  E. chi-square test
  E. chi-square test

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  Explanation

  The chi-square test is the most appropriate statistical test to determine whether series of frequencies or proportions are significantly different from each other. It is designed to describe with a single number how much the frequencies in each cell of a box of paired readings differ from the frequency we would expect if there were no relationship between the observed readings. If the observed readings are similar to expected readings, the chi-square will be a small number. If there is a greater difference, the chi- square will be larger. The mathematical equation is:

  

• Question 660:

  Select the ONE best lettered option that is the most likely diagnosis of vaginal bleeding in pregnancy. Each lettered option may be selected once, more than once, or not at all.

  A21-year-old woman last menstruated 6 weeks ago. Her menses are usually every 2830 days. She has a past history of chlamydia. One week ago she had a positive home pregnancy test. She complains of mild left lower quadrant pain. Quantitative serum chorionic gonadotropin (hCG) concentrations 2 days ago and today are 6850 and 7685 mIU/mL, respectively. No intrauterine pregnancy is identified by transvaginal ultrasound.

  A. threatened abortion
  B. gestational trophoblastic disease
  C. cervicitis
  D. placenta previa
  E. placental abruption
  F. uterine rupture
  G. placenta accreta
  H. uterine inversion
  I. uterine atony
  J. vaginal lacerationK. tubal pregnancy
  K

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  Explanation

  Vaginal spotting accompanied by pelvic discomfort in a woman with a prior sexually transmitted infection suggests the diagnosis of an ectopic (tubal) pregnancy. Serum hCG concentrations should increase by at least 67% in 2 days during the first 68 weeks of pregnancy. The subnormal increase in this woman's serum hCG concentrations increases the probability of an ectopic pregnancy. However, approximately 15% of women with a normal intrauterine pregnancy will have a subnormal rise in hCG concentrations. Also, approximately 15% of women with an ectopic pregnancy will have a 48-hour rise in serum hCG concentrations greater than 67%. At hCG concentrations over 5000 mIU/mL, the absence of an intrauterine pregnancy by transvaginal ultrasound provides additional evidence for the diagnosis of an ectopic pregnancy.