USMLE-STEP-2 Online Practice Questions and Answers

Correct Answer: D

Respiratory rate >30 is a poor prognostic sign in community-acquired pneumonia. Other patient factors include age greater than 65 years, coexisting illness such as cancer, liver disease, congestive heart failure (CHF), renal disease, systolic BP less than 90 mmHg, temperature greater than 40°C. Laboratory finding s associated with poor prognosis include arterial pH <7.35, BUN >30, sodium less than 130, glucose >250, and hematocrit <30%. These factors are often used to calculate the PORT (Pneumonia Outcomes Research Team) pneumonia severity index score which can be an aid in making treatment decisions. S. pneumoniae, Legionella, and S. aureus are the pathogens associated with poor prognosis, not Mycoplasma.

Correct Answer: C

The intent of staging is to judge the results of various treatments and to compare treatment results worldwide. Because advanced procedures such as venography, lymphangiography, MRI or CT scans, and laparoscopy are not universally available, staging of cervical cancer remains primarily clinical. Such tests as cystoscopy, proctosigmoidoscopy, barium enema, IVP, and plain radiographs of the abdomen and chest are permitted. Evidence of mucosal cancer confirmed by biopsy at the time of cystoscopy changes her diagnosis to stage IV cervical cancer.

Correct Answer: A

Multiple randomized-controlled trials have now demonstrated the benefit of administering antibiotics to women with PPROM at less than 32 weeks' gestation. Most importantly, these drugs prolong the latent period until labor begins, but reductions have also been noted inmaternal infection, fetal infection, fetal respiratory distress syndrome, and fetal intraventricular hemorrhage. Commonly used antibiotics are ampicillin and erythromycin, but efficacy has been noted with many different regimens. Cesarean delivery at this point is not indicated, but might need to be performed in case of nonreassuring fetal status or malpresentation (e.g., breech). Induction of labor generally takes place between 32 and 34 weeks if the patient's status remains stable, or sooner in the event of amniotic infection or other concerns. Amniocentesis may be performed to look for evidence of amniotic infection, but the likelihood of fetal lung maturity at this point is remote. Patients with previously placed cervical cerclages may be candidates for expectant management with the cerclage in place, but it would be inappropriate to place a cerclage after PPROM.

Correct Answer: E

The features that make placental abruption the most likely diagnosis are the amount of bleeding, chronic hypertension, and an excessively firm (even titanic) uterus that is tender to palpation. Women with a placental abruption may have no bleeding if placental separation occurs only in the center of the placenta. The other signs of pain and tenderness will be present.

Correct Answer: A

Prone sleeping is a major risk factor for sudden infant death syndrome (SIDS). Since the 1992 American Academy of Pediatrics (AAP) recommendation that infants be placed to sleep on their backs, the frequency of prone sleeping has decreased from 70 to 20%, and the SIDS rate has decreased by >40%. Side sleeping has a slightly higher SIDS risk than supine but is still safer than the prone position. Other risk factors include maternal smoking, soft bedding, overheating, younger maternal age, prematurity, low birth weight, and male gender. Rates among African Americans and Native Americans are two to three times the national average. The issue of bed sharing or cosleeping is controversial. There are reports of overlying by adults leading to suffocation, especially when the adult uses drugs or alcohol. Bed sharing with multiple family members may be hazardous; there is increased risk of overlying, entrapment, rolling into prone position, and use of soft sleeping surfaces. Some studies show that infants have more arousals and less slow-wave sleep during bed sharing; however, there is no epidemiologic evidence that bed sharing is protective.

Correct Answer: C

Mild illness is not a contraindication to vaccination, nor is breast-feeding. Such live vaccines as MMR and varicella are not recommended for pregnant women, but may be safely given to their children. They are also not recommended in many immunocompromised children; however, it is recommended that household contacts receive the vaccinations to decrease the patient's chances of exposure. It is not necessary to restart a vaccine series if there has been a long gap between immunizations.

Correct Answer: G

Giardiasis may cause cramping and a chronic diarrheal syndrome, with malabsorption and weight loss. Its distribution is worldwide, particularly where hygienic standards are not high. It also occurs sporadically in high-risk individuals. Streptococcal pyoderma, including erysipelas and impetigo, has been demonstrated to precede acute glomerulonephritis. Even when appropriate antibiotics are given in adequate dosage and duration for these conditions, renal damage may still result. Prevention thus consists of wound care, including cleaning wounds well and removal of crust. Mycoplasma infections are particularly common in families with younger children. They are frequently imported to the family by school-aged children, leading to a low-grade fever and persisting tracheobronchitis in the parents, or more acutely, an atypical pneumonia. G. lamblia is found in up to 20% of homosexual males, and may cause chronic diarrhea, although in these patients it tends to be asymptomatic. E. coli was first reported as a cause of watery diarrhea in nurseries in the 1940s. Although nursery epidemics with enteropathogenic serotypes had decreased in recent years in the United States, the increase of infant- child day care centers has resulted in their relatively frequent occurrence. Furunculosis is most frequently caused by coagulase-positive staphylococcal infections. The public health significance of this largely relates to the hazards of skin infections in food handlers and subsequent staphylococcal toxin in the food, leading to staphylococcal intoxication food-borne disease. H. pylori has been associated with gastric ulcers, but not with duodenal ulcers. Otitis media, whether acute or with effusion, commonly results from viral infection, such as by RSV. Various other organisms may be responsible including Streptococcu pneumoniae, H. influenzae, and others. C. perfringens, with rare exceptions, is transmitted in a meat dish prepared in bulk. Under propitious circumstances for the organism, especially on cooling of the food, bacterial multiplication can be very rapid. Symptoms begin to occur in the affected population in about 12 hours. Epidemic typhus is a rickettsial illness. Man is the host and long-term reservoir. The vectors are body lice (P. humanus corporis). The rickettsia are not present in human excretions and cannot be transmitted by person-toperson contact.

Correct Answer: F

Giardiasis may cause cramping and a chronic diarrheal syndrome, with malabsorption and weight loss. Its distribution is worldwide, particularly where hygienic standards are not high. It also occurs sporadically in high-risk individuals. Streptococcal pyoderma, including erysipelas and impetigo, has been demonstrated to precede acute glomerulonephritis. Even when appropriate antibiotics are given in adequate dosage and duration for these conditions, renal damage may still result. Prevention thus consists of wound care, including cleaning wounds well and removal of crust. Mycoplasma infections are particularly common in families with younger children. They are frequently imported to the family by school-aged children, leading to a low-grade fever and persisting tracheobronchitis in the parents, or more acutely, an atypical pneumonia. G. lamblia is found in up to 20% of homosexual males, and may cause chronic diarrhea, although in these patients it tends to be asymptomatic. E. coli was first reported as a cause of watery diarrhea in nurseries in the 1940s. Although nursery epidemics with enteropathogenic serotypes had decreased in recent years in the United States, the increase of infant- child day care centers has resulted in their relatively frequent occurrence. Furunculosis is most frequently caused by coagulase-positive staphylococcal infections. The public health significance of this largely relates to the hazards of skin infections in food handlers and subsequent staphylococcal toxin in the food, leading to staphylococcal intoxication food-borne disease. H. pylori has been associated with gastric ulcers, but not with duodenal ulcers. Otitis media, whether acute or with effusion, commonly results from viral infection, such as by RSV. Various other organisms may be responsible including Streptococcu pneumoniae, H. influenzae, and others. C. perfringens, with rare exceptions, is transmitted in a meat dish prepared in bulk. Under propitious circumstances for the organism, especially on cooling of the food, bacterial multiplication can be very rapid. Symptoms begin to occur in the affected population in about 12 hours. Epidemic typhus is a rickettsial illness. Man is the host and long-term reservoir. The vectors are body lice (P. humanus corporis). The rickettsia are not present in human excretions and cannot be transmitted by person-toperson contact.

Correct Answer: A

Alzheimer's disease is the most common form of dementia. Of persons with dementia, 5060% will have Alzheimer's. Vascular dementia is the second most common, accounting for about 1530% of dementias.

Correct Answer: A

One of the most significant findings here is that the woman, cooperative with the examination, has the score of 14 on the MMSE. Ascore of 2530 indicates no cognitive impairment, 2025 suggests possible mild impairment, and less than 20 is very strongly suggestive of cognitive impairment. This degree of change on the MMSE is not a normal sign of aging. In addition, there are no signs of psychosis or mania. Even if there were, in this woman with no previous sychiatric history, one would not likely consider psychosis not otherwise specified or mania. The time frame for dysthymia is not met by the "several days" length described here.

Correct Answer: C

Persons with personality disorders are rigidly bound to the use of patterns of defense and various traits that distinguish the disorders. All have problems with interpersonal relationships

Correct Answer: D

This elderly patient has metastatic adenocarcinoma of the prostate, and management is, therefore, aimed at tumor control for palliation of symptoms. This is achieved with hormonal manipulation, either by orchiectomy or exogenous estrogen therapy. Radical prostatectomy is indicated only for patients in whom the malignancy is confined to the prostate gland. Transurethral prostatectomy is used to treat benign prostatic hypertrophy, and is not considered adequate surgical therapy for prostatic malignancy. Cytotoxic chemotherapy may be useful as an adjunct to radical surgical excision of localized disease. Chemotherapy is not indicated for the treatment of metastatic disease. Radiation therapy has been used for the management of localized disease, and there is some evidence that it affords equivalent survival when compared to surgical excision. In patients with bone pain that is not well palliated with hormonal manipulation, radiation therapy may be useful.

Correct Answer: A

The gradual onset of left lower quadrant pain over a number of days with left lower quadrant abdominal tenderness and CT scan showing sigmoid colon inflammatory changes is most consistent with diverticulitis. Acontained perforation, either due to the diverticulitis or colon cancer, should be noted on the CT scan. There is no history of antecedent antibiotic therapy to suggest the diagnosis of pseudomembranous colitis. Though WBCs were present in the urinalysis, a diagnosis of pyelonephritis cannot be made on this basis alone, because pericolonic inflammation may be responsible for the WBCs. CT scanning is very accurate in diagnosing diverticulitis, so there is no need for any additional test. Barium enema and colonoscopy should not be performed in patients with suspected acute diverticulitis. The increased intraluminal pressure from either of these examinations may lead to free rupture of a contained abscess or phlegmon, leading to emergency surgery. However, either examination, or both, should be performed after complete resolution of diverticulitis (e.g., in 6 weeks' time) to evaluate for extent of disease, complications, and carcinoma. IVP and angiography are not indicated for diverticulitis. The appropriate management in this patient with his first episode of diverticulitis is medical management with IV antibiotics for gram- negative and anaerobic bacteria. Colon resection, either immediate or elective, should not be undertaken unless the patient's condition deteriorates or recurs. Bowel preparation cannot be performed safely in patients with acute diverticulitis. Anticoagulation has no role in therapy. Metronidazole or vancomycin therapy would be appropriate for pseudomembranous colitis, but not for diverticulitis

Correct Answer: B

A history of irregular menses from menarche suggests a functional disorder, such as polycystic ovary syndrome or attenuated adrenal hyperplasia attributable to an inherited enzyme deficiency. The absence of a unilateral ovarian mass on pelvic examination, the positive family history, and the early menarche favor a diagnosis of attenuated adrenal hyperplasia over that of a virilizing ovarian tumor. Women with 17hydroxylase deficiency or 11-hydroxylase deficiency are hypertensive. Women with 17- hydroxylase deficiency are also sexually infantile, not hirsute, because they are unable to produce androgens or estrogens in normal amounts. Women with 21-hydroxylase deficiency may have salt wasting and hypotension if the enzyme deficiency is sufficiently severe.

Correct Answer: A

Fluoxetine has the longest half-life of the current SSRIs (escitalopram's half-life is shorter--less than 24 hours), phenelzine is an MAOI and foods rich in tyramine can induce a hypertensive crisis. Venlafaxine can induce hypertension, especially at higher doses. Trazodone can rarely induce priapism (a painful sustained erection). Nortriptyline is a tricyclic antidepressant, and at high doses, it can cause arrhythmias.