NBME 15

34 y/o scientist is exposed to aerosolized 125Iodine while synthesizing a radiolabeled compound; What is the best treatment?

A Diabetic has sensation to pinprick and vibration decreased from just above the ankles distally; The patient is most likely to describe the pain as?

Explain why deoxygenated blood can carry more carbon dioxide for a given PCO2 than oxygenated blood?

What is the equation for ejection fraction?

23 y/o woman has a 3 day history of a drooping eyelid + right pupil is larger than the left + Right eye is looking down and to the right; Where is the lesion?

Methylprednisolone

3 y/o girl is infected with Mycobacterium avium intracellulare; This patient most likely has a defective function of what protein?

22 y/o basketball player who uses cocaine recreationally suddenly develops severe shortness of breath + Lung fields are hyperresonant and breath sounds are diminshed; Diagnosis

23 y/o man has a depressed mood, decreased energy, and dry skin + T4 and TSH concentrations are decreased; Diagnosis

1 hour after uncomplicated vaginal delivery, a women has continued heavy blood loss from the vagina + The uterus is soft and contractions have stopped; What drug would be most helpful?

15 y/o boy presents w/ right wrist pain that began when he landed on his hands after falling backward while skateboarding + Point tenderness to palpation of the radial aspect of the wrist between the abductor pollicus longus and extensor pollicus brevis tendon; This patient is at increased risk for what sequelae

Patient brings her grandmother in who has Alzheimers and is refusing to eat + The granddaughter appears worried and exhausted and is intermittently tearful; What intervention is most appropriate?

Fetal ultrasonography shows that ductus arteriosus has closed. Inhibition of what enzyme is most likely?

What property of an anesthetic explains rapid onset of action?

Man presents w/ a 2 day history of abdominal pain + Consumed large amounts of alcohol over the past few days + Lab shows serum amylase activity of 700 and serum lipase of 850 and serum Ca2+ of 7.5; Diagnosis

What is the role of IkB in the nuclear factor-kappa B (NF-kB) signal transduction pathway from IL-1 binding to IL-6 induction?

Define Stratification

9 y/o boy has mild mental retardation + frequent motor seizures + Pink to yellow papules in a butterfly distribution on the bridge of his nose, malar prominences + CT scan shows calcified nodules on the crest of gyri + ECG shows LV hypertrophy w/ associated narrowing of the aortic valve

Treatment with valproic acid, which inhibits histone deacetylase is started; What process does this affect?

Old man has sudden onset of blindness in the left eye + If patient remains to be blind in the left eye 6 months later, what will happen when the eye is illuminated?

A food handler has a fresh furuncle on his face as he prepares meat loaf; Eight of the 10 people who eat the meat loaf become ill within 4 hours, what symptom will they most likely have?

Woman presents with 6 month history of cutaneous flushing and diarrhea + X-ray of chest shows solitary nodule in the left lower lung; What compound is being secreted from this nodule?

18 month old boy with SCIDs requires a blood transfusion for severe anemia; What blood product should be given?

What hematologic abnormality is associated w/ SLE?

Shoulder pain is reproduced with resisted abduction of the shoulder when the shoulder is abducted 90 degrees and the arm is giving "thumbs down" sign; What tendon is injured?

1 month old boy is Albino; Skin biopsy would most likely show?

Patient has bilateral hydronephrosis; Describe the pressures in the kidney.

Woman develops a secreting adenoma of the parathyroid gland; What is most likely to be decreased?

An organism is resistant to ampicillin but sensitive to ceftriaxone; What is the most likely mechanism of this antimicrobial resistance?

Patient is hypotension + Abdominal examination shows guarding and a pulsatile periumbilical mass; What additional finding is most likely?

DiGeorge Syndrome is due to the aberrant development of the?

Slit like openings are visualized near the lateral ends of the top of the trigone region of the bladder; What describes this structure?

Patient has a 1 week history of loss of peripheral vision to the left in both eyes; Where is the lesion?

Man has BPH and develops urinary retention + A drug is admin that increases phosphoinositide turnover in the smooth muscle cells of bladder and has no effect on nicotinic synapses; What drug is this?

During skeletal muscle twitches, the ATP concentration does not fall appreciably because of what?

Newborn with NRDS has lungs with diminished ability to serve as sites of effective gas exchange; An increase in what parameter would explain this?

PPD test is positive in this patient; The casual organism is most likely to be present in what cell?

Where does lymph from cervix drain to?

Organophosphate poisoning treatment

Myasthenia Gravis patients have antibodies to?

20 y/o cyclist taking recombinant human erythropoietin has polycythemia; How?

Acetaminophen toxicity

Swallowing study shows a 4 cm posterior midline pouch protruding between the thyropharyngeal and circopharyngeus portions of the inferior pharyngeal constrictor muscle; What innervates these muscles?

Women is found unconscious + PE shows cool pale extremities, JVD, faint peripheral pulses, and crackles over the bottom two 3rds of both lung fields + Heart sounds are normal; What type of shock is this patient experiencing?

4 y/o boy has DMD; The most likely cause is a defective or absent protein in what area of muscle?

A defect in renal ammoniagenesis is suspected; What substrate is most likely the source of ammonia now?

43 y/o presents with altered consciousness + During the interview she stops talking mid sentence and has a blank look + She has repetitive lip smacking and picking movements of the hands + It last for 30 seconds; Diagnosis

Locate Arcuate Fasciculus on Brain image

Female patient is consuming cocaine while pregnant; The patients fetus is at increased risk for what?

Genomic typing shows that HIV strain has become resistant to ritonavir/lopinavir; The cause of this resistance is acquisition of of a mutation in a gene critical for what process?

5 y/o boy is stung on his foot by a bee + The area becomes edematous; The extravascular accumulation of fluid is most directly related to?

Stool culture grows Salmonella + Symptoms resolve within 36 hours but persist in milder forms for several more days; What would occur if the patient was treated with antibiotics?

Stress echocardiography shows hypokinesis of the posterior left ventricle w/ increasing activity levels; What is the most likely cause?

A metal worker collapses after exposure to unknown chemical + He smells like burnt almonds; What should you admin?

Patient is found to be homozygous for the phenylalanine hydroxylase gene at a point mutation (GT->AT) in intron 12 of the effected gene causing skipping of exon 12; What is the explanation for exon skipping in this patients affected gene?

Women comes to the physician because her menstrual period is 1 week late + She had unprotected sex with her bf 20 days ago; What describes the stage of development of the embryo at this time?

Vaccine against diphtheria confers protective immunity by inducing the formation of antibodies against a preparation composed of?

Microscopic examination of a biopsy specimen of the lesion shows atypical melanocytes spread along the basilar layer in the epidermis; What is the most likely cause of this finding?

Greatest risk factor for Sarcoidosis?

Leukemic cells that express class 1 MHC molecules and show rearrangement of the T-lymphocyte receptor Beta-chain gene D and J segments normally counterparts with?

Man participates in a clinical trial of a newly developed loop diuretic; What is the acid/base volume status after 3 days of treatment?

During induction of anesthesia, isoflurane is admin along with a second compound + Patient develops muscle rigidity and increased temps; What drug was most likely paired?

3 cm laceration orientated transversely over the palmer aspect of the distal forearm and located 2 cm proximal to the distal palmar wrist crease + Patient is unable to abduct left thumb + Sensation to pinprick is decreased over the palmar aspect of the thumb, index and middle fingers; What nerve is injured

Serum studies show increased concentrations of very long chain fatty acids, phytanic acid, and pipecolic acid; If hepatocytes were analyzed using electron microscopy, results would show absence of what organelle?

A man has a 4 month history of weight loss, abdominal pain, diarrhea + Stool analysis shows increased excretion of neutral fat and muscle fiber + Examination of tissue obtained on intestinal biopsy shows no abnormalities; This patient would respond favorably to?

What germ cell layer is the Esophagus derived from?

Patient has been taking warfarin since receiving an artifical heart valve 6 years ago because of endocarditis secondary to IV drug use; During the next 6 weeks, warfarin dosage required to maintain prothrombin time progressively decreases; What explains this finding?

36 y/o man heterozygous for LDL receptor def has a cholesterol conc of 330 mg/dl + After taking a drug, his cholesterol goes down to 200 mg/dl; What proteins would be upregulated as a result?

Vision screening is performed on 4000 people who are older than 65 years + Cataracts are found in 200.; Which of the following best describes the annual incidence of cataracts in this population?

Patient ingested 100 aspirin tablets in a suicide attempt; What additional hematologic finding is most likely abnormal in this patient?