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Discussion in 'USMLE Step 2 CK' started by orthopod, May 16, 2015.

  • by orthopod, May 16, 2015 at 8:02 PM
  • orthopod

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    If you find an incorrect answer, or an answer that I have not included here, let me know, and I'll make the change. A correct answer means that you correctly selected it on your version and it did not show up in your 'extended feedback.' You can discuss question topics here, or in a separate thread. It’ll take some time to transcribe all the questions, so I’ll continue to edit/update/add questions over the next few days.

    Block 1 part 1
    1. 22yo Primi admitted in labor. Pregnancy was complicated by 3 UTIs, the last one at 22 weeks gestation. She’s now taking daily nitrofurantoin. Pt is otherwise healthy. What’s causing the recurrent UTIs?
    - Urinary Stasis

    2. 4yo boy with 3-day hx of cough, fever, runny nose. No wheezing, vomiting, or diarrhea. 75th %ile for height, and 10th %ile for weight. T 37.5. Cap refill is 2 sec. Exam shows clear rhinorrhea. Breath sounds normal. There is a media tab to view the cardiac exam. Dx?
    - URI

    3. 42yo woman with generalized weakness, lethargy, and double vision for 2 weeks. Chest X-ray shows upper anterior mediastinal mass. Dx?
    - Thymoma

    4. 4mo old brought to ER after an apparent seizure. Pt has vomiting 6 times over the last 2 days, feeding poorly, and sleeping more than usual. Pt is lethargic and afebrile. Anterior fontanel is tense, bilateral retinal hemorrhages. Dx?
    - Child abuse

    5. 52yo man with excruciating pain/swelling of his great toe since undergoing appendectomy 10 days ago. Celecoxib has provided no relief. Temp is 37.6. Exam shows red/swelling great toe and tender MTP joint. Most appropriate next step?
    - Indomethacin

    6. During a sports physical, a healthy 14-yo boy has a BP of 150/90. Previous BP checks have been normal. 6 ft 2 in and weights 180 lb. BMI is 24. Exam is normal otherwise. Most appropriate next step?
    - Repeat BP check in 4 weeks

    7. 19yo man brought to ER by police after found standing in his neighbor’s living room in the middle of the night. He is conscious but remains mute during questioning. Temp 37C, respirations 18/min, BP 160/95. Exam shows bilateral nystagmus, constricted pupils, hypertonia, and decreased sensation to pinprick. Substance?
    - PCP

    8. Officer investigates an outbreak of illness at a picnic. Onset of nausea and vomiting 3 to 4 hours after attending the picnic. All those affected recover without Rx. Egg salad was the vehicle of transmission. What is the factor most commonly contributing to an outbreak of this type?
    - Inadequate refrigeration of implicated food

    9. 2 days after beginning ACTH therapy for MS, a 47yo woman exhibits bizarre behavior. She is easily angered and thinks the nurses are terrorists. She’s been pulling out her IV and walking down the halls at night. Muscle strength in lower extremities is 2/5. On mental status exam, she is fidgety, labile affect, and is easily distracted. Oriented to person, but not place or time. Most appropriate Rx?
    - Haloperidol

    10. 50yo F with 5-year Hx of metastatic breast cancer has SOB for 8 hours. Pulse 116/min, resp 32/min, BP 90/60. End-inspiratory crackles heard at base of both lungs. JVD present. Distant heart sounds. ABG shows: pH 7.50; Pco2 28; Po2 78. XR shows cardiomegaly, ECG shows alternating QRS amplitude patterns. Echo shows paradoximal motion of the interventricular septum and a pericardial effusion. Most appropriate next step?
    - Pericardial window.

    11. 14 month boy brought in for well-child exam. Mother is worried because he is not yet walking on his own. He will stand for several seconds before falling. He can empty raisins from a cup and tries to eat with a spoon. 25th %ile for length and 30th %ile for weight. Exam shows no abnormalities. Most appropriate next step?
    - Reassurance

    12. Asymptomatic 23yo M in for preemplyoment evaluation. Exam shows normal findings. PPD shows 16 mm of induration & erythema. He has had no previous PPD tests and hasn’t been exposed to anyone with active TB. XR shows no abnormalities. Sputum contains no acid fast bacilli. Most appropriate next step?
    - Treat latent TB now

    13. Previously healthy 26yo M in ER with SOB for 3 weeks and painful bumps on his legs for 1 week. T 38.2, P 80/min, BP 140/85. Exam shows 2- to 3-cm tender, red nodules on anterior shins. CXR shows bilateral hilar fullness. Which serum abnormalities is most likely in this patient?
    - Increased calcium

    14. 47yo F with fever, nausea, vomiting, and severe headache for 24 hours. T 39. Exam shows weakness of right upper extremity and nystagmus, optic fundi cannot be visualized. Kernig sign is present. Most appropriate next step in diagnosis?
    - CT of head

    15. 47yo F brought to ER 30 minutes after a MVC, unrestrained driver. Severe neck pain and mild chest and abdominal pain. P 95/min, Respirations 20/min, and BP 120/80. Exam shows severe tenderness of the cervical spine at C5. Bruise and mild tenderness over lower sternum and upper abdomen. Neuro exam is normal. CXR is normal except for slightly widened mediastinum. Cervical spine XR shows C5 facet fracture. Abdominal XR is normal. Most likely location of the life-threatening cardiovascular injury?
    - Thoracic aorta

    16. 18yo primi at 37 weeks’ gestation admitted in labor. Regular contractions every 3 minutes. Pregnancy complicated by several episodes of genital herpes, most recent episode 6 weeks ago. No lesions or prodromal symptoms since last episode. Vaginal exam shows no lesions. Membranes are intact. Fetal movement has been appropriate. Cervix 100% effaced, 5cm dilated, vertex at -1 station. Most appropriate next step?
    - Amniotomy and vaginal delivery

    17. 4yo girl with 5lb weight loss during the last 2 months. No Hx of illness, on no medications, immunizations up to date. 50th %ile for height, 25th %ile for weight. Occasional crackles over right middle lung field. Intradermal testing with PPD, tetanus, and antigens for candida and trichophyton is nonreactive at 72 hours. WBC count is 5100. Nucleic acid hybridization testing of gastric aspirates shows TB. Most likely explanation?
    - T lymphocyte dysfunction

    18. 27yo F with 5 day history of headache, severe, diffuse abdominal pain, nausea, vomiting. Pain is exacerbated by eating and relieved by vomiting. Vomitus originally had semisolid content with green fluid, and now only contains clear yellow fluid. Hx of Crohn dz treated with prednisone, tapered over the last 2 weeks, mesalamine, and azathioprine. LMP 7 weeks ago. Sex w/ 1 partner, use condoms inconsistently. Temp 38.4, P 120/min, Resp 22/min, BP 90/50. Dry oral mucosa, pale conjunctiva, distended abdomen, diffusely tender and tympanic. Decreased bowel sounds. Pelvic exam is normal. Labs: HCT 31% WBC 15k, amylase 300, lipase 9. Dx?
    - SBO

    19. 37yo F with malaise, muscle aches, painful vulvar blisters, vaginal discharge, and dysuria for 3 days. Had sex with new partner 7 days ago. T 38. Exam shows bilateral painful inguinal lymphadenopathy and numerous 1-3 mm vesicles and ulcers on labia majora and minora, perineum, vulva, mons pubis. Next step in diagnosing these lesions?
    - Cx for herpes

    20. 52yo F with personality change since death of close friend 2 weeks ago. Irritable, less sleep, speaks rapidly, jumping from topic to topic. She’s had past episodes excessive sleeping, decreased energy, and loss of interest, but never thought these symptoms were severe enough to seek medical attention. Mental status exam shows loud, rapid speech, and flight of ideas. She says she is not sad, but rather uplifted by her friend’s death. She hears her friend’s voice and communicates with her. Dx?
    - Bipolar d/o

    21. 6 hours after CABG, 62yo experiences drop in BP from 120/80 to 100/85. Urine output decreases from 60 to 10 mL/h, and cardiac output decreases from 6 to 3 L/min. Pulmonary artery diastolic pressure has decreased . CXR shows widened mediastinum. Most appropriate next step?
    - Surgical exploration of mediastinum

    22. Homeless 66yo M with jaundice for 1 week. Eats irregularly, 20lb weight loss, over the past year. 20-year Hx of alcoholism. Icteric sclerae, palmar erythema, and spider angiomata. Serum Mg is 0.8. Serum studies most likely to show?
    - Decreased Calcium

    23. 24yo F with amenorrhea for 7 days. 8-year Hx of anorexia. Compared to other women her age, she has an increased risk for?
    - Osteoporosis
     
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Comments

Discussion in 'USMLE Step 2 CK' started by orthopod, May 16, 2015.

  1. orthopod
    Thanks for the post, @Misao !

    Remember, that with the NBME, they usually want you to think of the less invasive method of managing a patient first. This case is no different, and elevating the head of the bed would be the best choice. NG suction may also help with preventing aspiration pneumonia, but would you really want someone to sit there and suck everything out of your throat (and who knows for how long!)?
  2. annaK12345
    Block 4 part 1 and part 2 isn't showing up- do u mind reposting it please?
  3. orthopod
    @annaK12345 I haven't had the time to finish posting block 4. If you have any specific question, you can post it here, and I'll provide you with the correct answer. It will also help me a ton because it will allow me to post less.
  4. annaK12345


    I had a question on number 15 on block 4- an 82 year old man with CHF comes to doc for f/u exam. one month ago, he had worsening dyspnea while lying in bed at night and walking up stairs, and his dose of furosemide was increased. his only other medication is lisinopril. he was dx with chef 5 years ago after MI. he had coronary angiography and stent at that time. no CP since them. also has a 10 year hx of well controlled CKD. creatinine conc have ranged from 1.3- 1.5 and urinalyses have shown no protein. today his pulse is 90/min, rest are 14/min and BP is 130/86/ cardiopulmonary shows no abnormalities. there is trace edema of ankles, which has decreased since examination 1 month ago. serum studies show:

    1 month ago: na-138, K 4, cl 101, HCo3- 26, bun-15, cr-1.8
    today: NA-140, k-4.2, cl-103, hco3-28, bun-24, cr-2.3

    urinalysis shows no abnormalities. which of the following is the most likely explanation for the change in lab values during th past month
    a. decreased renal blood flow
    b. glomerular inflmmation
    c. renal cortical necrosis
    d. renal interstitial inflammation
    e. renal tubular necrosis (WRONG)
    f. renal tubular destruction

    If you could please help I would really appreciate it! Thanks!
  5. orthopod
    @annaK12345 the answer is a. decreased renal blood flow

    Don't forget the effects of furosemide - It'll decrease total intravascular volume and result in a pre-renal AKI. His edema is decreasing which supports the notion that he has decreased blood flow. Lastly, none of the other answer choices make sense

    Hope that helped!
  6. PlanetCruiser
    Item 30 block 4:
    A previously health 67 yo man has an aching burning sensation in the distal lower extremities for 3 wks, worse with walking and relieved by elevating his feet. Metatarsophalangeal joints and ankles are warm, swollen, tender, and erythematous. There is clubbing of finger and toes. Dx?
    -?? I guessed on this and ITS NOT E. I think Bronchogenic carcinoma given the clubbing and likely neuropathy of lung cancer.



    Item 26 block 4
    32 y.o W brought to ER, 2 day hx of vomiting, diarrhea and right sided pelvic pain. Last mentrual period was 3 wks ago. Temp 102.2, RR20, P100, BP 120/70. Abdo exam shows right lower quadrant tenderness with rebound. Decreased bowel sounds. Pelvic exam shows right adnexal tenderness. Negative serum pregnancy test. Labs: Hg 12 Leukocytes 15,000 Seg PMNs 80% Bands10% Lymphs5% Monos 5%.

    Ultrasound shows no adnexal masses. Most likely dx?
    --?? It is NOT H, Tubo-ovarian abscess



    item 16 block 4
    Previously healthy 18 yr old woman, lump in her neck she first noticed 1 month ago. Otherwise asymptomatic. Exam shows 3cam left supraclavicular lymph node that is firm and rubber. Spleen is 3cm below left costal margin. Remaining exam is normal. Labs will most likely show which?
    --?? Its NOT C, increased serum calcium concentration


    item 11 block 4
    20 yo man, brought to physician by his parents b/c of auditory hallucinations and bizarre behavior over 1 year. Dropped out of college, moved home, and not attempted to find job. He says he has been feeling strange, like in a dram and talks to his great great grandfather who died 50 yrs ago. He was diagnosed with HepA 2 yrs ago after an episode of jaundice, and has been treated with thyroxine for hypthyroidism for past 6mths. P68, rr 10, bp 100/70. Physical exam: hyperreflexia of lower extremities, milk resting tremor of upper extremities. On mental exam, his voice is monotonous, face is immobile, seems very anxious. He stares at physician and barely answers any questions. Serum studies: T.bili 1 TSH 1 AST 21 ALT 20

    Urine Tox Screen is Negative. What is most likely dx?
    --?? Not F, psychotic disorder due to general med condition


    item 9 block 4
    25 y/o woman, at the doctors for tremulousness and fatigue for 1 month. T 99F, P 120. She appears nervous. Ophthalmologic exam no abnormalities. Thyroid gland is barely detectable by palpation and non tender. Iodine uptake is decreased. Dx?
    --?? NOT E, Neoplastic infiltration, i was just thinking cold nodule.

    item 4 block 4
    70 y.o W brought to ER 3hrs after onset of substernal chest pain, weakness and dsypnea. She had MI 6 months ago and has had recurrent chest paon on exertion treated with nitroglycerin. T98.8, rr 22, bp 60/40. Exam is normal. EKG is shown. Dx?
    --Not H, Vfib, so I guess its Afib?

    Thank you for this very concise and organized forum! It has been super helpful knowing the answers are right and not just opinions. Super appreciate it.
  7. PlanetCruiser
    21. 6 hours after CABG, 62yo experiences drop in BP from 120/80 to 100/85. Urine output decreases from 60 to 10 mL/h, and cardiac output decreases from 6 to 3 L/min. Pulmonary artery diastolic pressure has decreased . CXR shows widened mediastinum. Most appropriate next step?
    - ?
    -Answer: surgical exploration of mediastinum
  8. PlanetCruiser
    12. 57yo F with pain over left groin and anterior thigh for past year. Active range of motion of hip joint reproduces pain. 20-degree hip flexion contracture. ESR is 20; pelvic XR shown; Dx?
    - Answer: Osteoarthritis


    14. 17yo girl in MVC as unrestrained driver. Arrives on a backboard with C-collar. During attempts to administer 100% O2, patient is combative. Facial trauma and open facial fractures. Chest severely bruised. Makes gurgling sounds when she breathes. Most appropriate initial step in management?

    --Answer: Cricothyrotomy is correct, the patients has open facial fractures and demonstrating airway compromise with gurgling so you do cricothyrotomy. I got this correct.


    19. 2 hours after repair of perforated gastric ulcer, 75yo W has multifocal PVCs. Hx of CHF treated with Digoxin and diuretics. Most likely abnormal serum concentration?
    - Decreased potassium,
    -->why is this the answer if Dig toxicity causes HYPERkalemia?
  9. orthopod
    @PlanetCruiser I've bolded the answers above. Please let your friends know about our site so we can continue to have productivity and contribution! Don't forget to post your exam experience in the other thread ;)
    PlanetCruiser likes this.
  10. orthopod
    You're right, but remember that dig toxicity OCCURS when potassium is low. Diuretics are causing her hypokalemia, and then she developed the side effects of digoxin, which include PVCs.

    Thanks for your help on the other ones!
    Rashyda O and PlanetCruiser like this.
  11. PlanetCruiser
    item 16 block 4
    Previously healthy 18 yr old woman, lump in her neck she first noticed 1 month ago. Otherwise asymptomatic. Exam shows 3cam left supraclavicular lymph node that is firm and rubber. Spleen is 3cm below left costal margin. Remaining exam is normal. Labs will most likely show which?
    --?? Its NOT C, increased serum calcium concentration
    Answer is D, increased serum lactate dehydrogenase activity
    Why is the answer increased lactate dehydrogenase? I am not picking up the message or the disease process in this question. Thank you!
  12. orthopod
    @PlanetCruiser - 'firm' 'rubbery' are buzzwords that lead you to a neoplastic process. Enlarged spleen further points you in this direction.
    She probably has a leukemia. And remember with leukemia, high cell turnover rate = high LDH.

    Now, you may have thought this was Mono. But this is less likely given that there are no other symptoms that we associate with mono.
  13. vanib
    po2/fio2 =56/.21=266 . for me it seemed like ARDS. dont you think so? and what makes it specifically points towards fat embolism? Thanks
    btw this is really useful forum! but this nbme was a piece of ****!
  14. orthopod
    @vanib great question. The po2/fio2 you mentioned may point us towards ARDS. However, there are many other features of ARDS and its diagnosis you should review (it's a complex pathological process and very high yield for step 2).

    Specifically, the long bones of the body contain significant amounts of fat, and when fractured, this fat can be released into the blood stream and leave a risk of a fat embolism. The symptoms in the question are classic for a fat embolism (review first aid/UWorld). Don't let the 'fluffy infiltrates' fool you into thinking it's ARDS. Hypoxemia here is caused by the fat embolism.

    Good luck, and let me know if you have any other questions! Don't forget to post your exam experience
  15. vanib
    @orthopod . Thanks for the quick response. well, then it comes down to just broken bones that actually points towards fat embolism.
    if we ignore the fact the pulm embolism usually is on 7th day,I wondering about why isnt it qualified for Pulm. embolism?
    Thanks again!!! :) ill definitely post my exam experience and let my junior and friends know about this forum! this is coool!!
  16. orthopod
    The broken bones only constitute part of it. The skin petechiae over the chest are very classic to fat embolism, and you wouldn't see that with pulmonary emboli. More details according to PubMed:

    "Arterial blood gas analysis showing an unexplained increase in pulmonary shunt fraction and an alveolar-to-arterial oxygen tension difference, especially within 24–48 h of a sentinel event associated with FES, is strongly suggestive of the diagnosis. Blood gases will show hypoxia, with a paO2 of less than 60 mmHg along with the, and presence of hypocapnia.

    Thrombocytopenia, anemia, hypofibrinogenemia, and increased erythrocyte sedimentation rate (ESR) are seen in FES, but are nonspecific findings. A decrease in hematocrit occurs within 24–48 h and is attributed to intra-alveolar hemorrhage.

    Cytological examination of urine, blood, and sputum may detect fat globules that are either free or within macrophages. This test is not sensitive and its absence does not rule out fat embolism. Fat globules in the urine are common after trauma. Preliminary investigations of the cytology of pulmonary capillary blood obtained from a wedged pulmonary artery catheter revealed fat globules in patients with FES and showed that this method may be beneficial in early detection of patients at risk." http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2700578/


    I would be hesitant to only think about PE on day 7. A PE typically doesn't occur in the first 1-2 days, but in an immobile patient (after significant orthopaedic injury or surgery), a PE may develop quite rapidly.
  17. vanib
  18. Sauga
    Block 2- 20. 55yo F with metastatic breast cancer admitted for confusion progressing to obtundation over past 24 hours. Barely arousable. Most likely abnormal serum concentration?
    - Increased sodium (Wrong according to my NBME expanded feedback)
    According to FA Breast CA is one of the causes of HyperCalcemia
    UW --> breast Ca can cause hyperCa via production of PTHrP
    Side note--> other tumors that can cause hyperCa through PTHrP production- Squamous Cell Ca ( e.g lung, head, neck esophagus), renal and bladder CA, ovarian and endometrial CA
  19. orthopod
    Thanks for the update @Sauga ! A patient with metastatic breast cancer likely has numerous abnormal lab findings, it's reasonable to say increased calcium is the culprit here. Can anyone confirm that increased calcium is the correct answer?

    After looking at this question again, I would in fact consider decreased sodium as the answer. Metastatic lesions in the brain can result in SIADH and a decreased sodium level. The reason I feel stronger towards sodium as the culprit than calcium is that sodium is known for causing 'obtundation' as explained here. Hypercalcemia may cause confusion, but increased calcium is better known for causing 'stones/bones/groans/psychiatric overtones,' none of which is described in the case.

    It would be great if someone who got this answer correct could let us know. @vanib ?
    Sauga likes this.
  20. Sauga
    Block 3 12. 37yo F G3P3. Exam shows 3-cm, nontender, fluctuant mass involving left posterior vulva underlying the mucosa of the vestibule and external to the hymenal ring. Dx?
    - Bartholin duct cyst (correct ans)

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