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

USMLE USMLE-STEP-2 Online Questions & Answers

• Question 431:

  A 25-year-old male graduate student presents at a university hospital emergency department complaining of a sudden onset of a pounding in his chest, a feeling of choking, and shortness of breath. He reports that things somehow suddenly seem unreal, and he is afraid he is dying of a heart attack. An electrocardiogram (ECG) shows normal sinus rhythm and no abnormalities You encounter this patient 1 year after the onset of his symptoms. He has not been very compliant with his medications, or appointments. Now he reports he rarely leaves his home and avoids places and social situations where he feels he cannot readily escape. When he does go places, he reports having an escape plan arranged. Which of the following best describes this condition?

  A. social phobia
  B. claustrophobia
  C. arachnophobia
  D. agoraphobia
  E. simple phobia
  D. agoraphobia

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  Explanation

  Agoraphobia is most often associated with panic disorder. It involves a severe fear of and avoidance of entering social situations where it is difficult to get help or escape from. Arachnophobia is the phobia of spiders, claustrophobia is a phobia of closed spaces. Social phobia is an excessive, persisting fear of social situations in which embarrassment can occur.

  Specific (simple) phobias are among the most common mental disorders and involve an excessive fear of an object or specific situation which produces an avoidance of the object or situation.

• Question 432:

  You provide health services for employers in your community. The employers explain to you that they appreciate efforts to contain costs because their insurance premiums are experience rated. Which of the following describes why employers are concerned?

  A. An experienced management team has set new rates for the employers.
  B. The employers pay the cost of service as out of pocket expenses.
  C. Everyone in the community pays the same rate for insurance based on community charges and overheads.
  D. The employer pays a large deductible premium.
  E. An employer's rates reflect past utilization by the employer.
  E. An employer's rates reflect past utilization by the employer.

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  Explanation

  The insurance company charges premiums to the employer based on "experience rating," which means charges are based on past utilization of service. To control premiums in the future, control utilization now. Community rating would be different, in that risk would be spread across a broader community. Community rating makes insurance more affordable for individuals or groups that use a lot of health care, but removes incentive to control costs.

• Question 433:

  A 25-year-old male graduate student presents at a university hospital emergency department complaining of a sudden onset of a pounding in his chest, a feeling of choking, and shortness of breath. He reports that things somehow suddenly seem unreal, and he is afraid he is dying of a heart attack. An electrocardiogram (ECG) shows normal sinus rhythm and no abnormalities

  If this patient continues to experience similar episodes over the next 2 months, with substantial apprehension about the episodes, which of the following drugs would be most appropriate for the treatment of this patient's condition?

  A. paroxetine
  B. buspirone
  C. ziprasidone
  D. propranolol
  E. haloperidol
  A. paroxetine

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  Explanation

  If the patient continues to suffer panic attacks for a substantial period, he is said to be suffering from panic disorder. SSRIs, such as paroxetine, are frequently effective and generally safe drugs for the treatment of panic disorder. Despite its usefulness in treating generalized anxiety disorder, buspirone seems to be ineffective in treating panic. Beta-blockers such as propranolol may block symptoms of palpitations or tremor, but are generally not as effective against panic attacks as are SSRIs. Antipsychotic medications such as ziprasidone and haloperidol are not appropriate medications for the first-line treatment of uncomplicated panic disorder.

• Question 434:

  A 45-year-old man presents to the physician's office for evaluation of a skin lesion on his abdomen. He states that the lesion has been present for 1 year, but has recently enlarged over the last 2 months. The mass is nontender, and he is otherwise asymptomatic. Past history is unremarkable. Examination reveals a 3-cm, pigmented, irregular skin lesion located in the left lower quadrant of the abdomen, as shown in Figure. Heart, lung, and abdominal examination are normal. There are no palpable cervical, axillary, or inguinal lymph nodes. Chest x-ray and liver function tests are normal.

  

  Which of the following is the most appropriate next step in management?

  A. wide excision with 2 cm margin
  B. wide excision with 2 cm margin and SLN mapping
  C. shave biopsy
  D. excisional biopsy with 12 mm margins
  E. Mohs' surgical excision
  D. excisional biopsy with 12 mm margins

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  Explanation

  Amulticolored brown or black pigmented lesion with irregular borders should raise the concern of melanoma. Squamous cell carcinoma usually presents as an erythematous papular nodule. The most common type of basal carcinoma presents as an ulcerative, well-circumscribed nodule, although occasionally it may be pigmented and confused with melanoma. Merkel cell carcinoma appears as red to purple papular nodules. Keratoacanthoma is a well-circumscribed keratotic lesion that may regress without treatment. The most appropriate next step is to perform an excisional biopsy with narrow margins to confirm the diagnosis and determine depth of invasion. Shave biopsy would yield a pathologic diagnosis, but would not allow appropriate staging and is never recommended. The margin of resection and determination of lymph node management would depend on the depth of invasion of the melanoma measured in millimeters. Therefore, wide excision is not recommended until the depth of invasion of the lesion is determined by excisional biopsy with narrow margins. Mohs' surgery should be considered for nonmelanoma tumors but is not recommended for melanoma.

• Question 435:

  For the screening tests listed below, select the screening schedule that is appropriate for women (as per the U.S. Preventive Services Task Force [USPSTF], The Guide to Clinical Preventive Services, 2006) Fecal occult blood testing (FOBT)

  A. do not routinely screen
  B. yearly over age 50
  C. at first prenatal visit
  D. every 12 years at age 40 and older
  E. every 12 years at age 50 and older
  F. every 3 years following an initial examination, but not after age 65
  G. every 3 years at age 50 and older
  E. every 12 years at age 50 and older

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  Explanation

  The USPSTF strongly recommends that men and women aged 50 or older be screened for colorectal cancer. Various methods exist for screening and the optimal interval for screening varies based on the method of screening. Current options for screening average risk individuals include FOBT every 12 years, sigmoidoscopy every 5 years, colonoscopy every 10 years, and other tests. Higher-risk individuals, those with a first-degree relative with a diagnosis of colon cancer before age 60, should receive screening at an earlier age and at shorter intervals.

• Question 436:

  A23-year-old university student has lost interest in his master's degree program. His two friends who bring him to the psychiatrist say he has been isolating himself in his room and has covered all electrical appliances and outlets with duct tape claiming that "electromagnetic waves are disturbing the microchip in my brain." He acknowledges that he once took a medication for the same problem with the "microchip," but then he became unbearably restless, could not sit still, and felt that he was "crawling" inside.

  According to the patient's psychiatric symptoms, select the most appropriate medication. Presume no medical problems other than those mentioned.

  A. amitriptyline
  B. clozapine
  C. divalproex
  D. fluoxetine
  E. hypericum perforatum
  F. olanzapine
  G. lorazepam
  H. propranolol
  I. temazepam
  J. thiothixene
  F. olanzapine

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  Explanation

  This man's symptoms are psychotic in nature and somewhat bizarre. In addition, the information strongly suggests that he is very sensitive to the extrapyramidal effects of the traditional antipsychotics. Olanzapine, an atypical antipsychotic with very few extrapyramidal effects, would be a good choice here.

• Question 437:

  Several groups of organic compounds are associated with serious toxic effects when used in the manufacture of textiles and materials; often found in manufactured homes

  A. nitrosamines
  B. epoxy compounds
  C. PCBs
  D. formaldehydes
  E. organophosphorus compounds
  D. formaldehydes

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  Explanation

  Formaldehyde commercial solutions contain up to 15% methanol. Formaldehyde has numerous industrial applications including, use as a base for urea formaldehyde resins. The gas is an irritant to the eyes and upper respiratory mucosa. The odors of products manufactured with formaldehyde products have been responsible for actions against manufacturers of tightly built manufactured homes.

• Question 438:

  A 12-year-old boy comes to the clinic for a sports physical. He is new to your practice. He comes with his foster mother, who states that he was recently placed in her care because of his mother's problems with drug abuse. Although a complete medical history is not available, she knows that he has not received regular care. He does not have any chronic medical problems. She also knows that his father died of heart disease when he was 35. On physical examination, the boy's height is greater than the 95th percentile. His arm span exceeds his height.

  Which of the following is the most likely cause of his tall stature?

  A. Ehlers-Danlos syndrome
  B. Kleinfelter syndrome
  C. Marfan syndrome
  D. Noonan syndrome
  E. Williams syndrome
  C. Marfan syndrome

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  Explanation

  Marfan syndrome is a genetic disorder of connective tissue. It is transmitted in an autosomal dominant manner. Patients have tall stature and skeletal disproportion, where the arm span exceeds the height. Other important clinical features include subluxation of the ocular lens which occurs in 5080% of patients. Progressive dilatation of the aortic root and ascending aorta can lead to dissection or rupture.

• Question 439:

  A fourth-year medical student on an emergency medicine clerkship is fascinated by the number of personality disordered patients who come to the emergency room on weekends. Which of the following personality disorders belongs to cluster A (odd, eccentric) in the DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders, 4th ed., Text Revision) classification of personality disorders?

  A. schizoid personality disorder
  B. borderline personality disorder
  C. antisocial personality disorder
  D. avoidant personality disorder
  E. obsessive-compulsive personality disorder
  A. schizoid personality disorder

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  Explanation

  Schizoid personality disorder is characterized by a pattern of pervasive social detachment with a narrow range of emotional expression. Schizoid persons seem to be fairly content with a lack of intimacy and are considered odd by persons around them. This contrasts with the picture of individuals with avoidant personality disorder, who long for social interaction, but feel inadequate and riddled with self-doubt in social situations. Like individuals with obsessive-compulsive disorder, people with avoidant personality disorder are categorized as having a cluster C (anxious, fearful) personality disorder; whereas, those with borderline personality disorder or antisocial personality disorder have problems characterized by engaging in impulsive behaviors and are classified as having a cluster B (dramatic, impulsive) personality disorder.

• Question 440:

  A 30-year-old woman who has been human immunodeficiency virus (HIV) positive for 4 years was recently diagnosed with AIDS.

  Which of the following immunologic abnormalities would be expected?

  A. increased numbers of CD4+ (helper) T cells
  B. decreased number of CD8+ (suppressor) T cells
  C. cutaneous anergy to usual skin test antigens
  D. normal B-cell function
  E. increased natural killer cell function
  C. cutaneous anergy to usual skin test antigens

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  Explanation

  The new case definition for AIDS in 1993 added pulmonary tuberculosis, invasive cervical cancer, and recurrent pneumonia. This CDC classification system is divided into three categories: category A is symptomatic infection with HIV and includes acute illness and persistent lymphadenopathy; category B includes conditions attributed to HIV infection, such as oral thrush, herpes zoster, and peripheral neuropathy; category C is the AIDS surveillance cases. Anergy to common skin test antigens is a common finding with HIV infection. There is a decline in CD4 cell numbers, a relative increase in the number of T8 cells, which results in a decreased T4:T8 ratio of less than 1. Functional abnormalities occur in both B cells and natural killer cells, which accounts for the increase in certain bacterial infections seen in advanced HIV disease. Elevation of beta2 submicroglobulin, a serologic finding reflecting immunologic dysfunction, is a fairly reliable marker of progressive immunologic decline and the subsequent development of AIDS.