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50yo M presents with 3-days of fever and 2 months of fatigue. He has diffuse cervical LAD and HSM. Labs show *anemia*, *thrombocytopenia*, and *leukocytosis* with immature forms.
Most likely diagnosis?Contrast with *myelofibrosis* --------- Correct Answer -------- *Leukemia* or more generally, hyperproliferation of hematopoietic progenitor cells
Myelofibrosis occurs in two phases:
- *Proliferative* - thrombocytosis, leukocytosis, etc.
- *Pancytopenic* - low everything
*The fact that there's an abundance of lymphocytes and decreased RBC/plt means that there's simultaneous proliferation and crowding out of other cells*
What is the mechanism of C. diff?
Be very general --------- Correct Answer -------- Toxin-induced inflammation of colonic mucosa
An elderly patient with a long history of COPD presents with mild respiratory distress, early satiety, weight loss, JVD with prominent a wave, distant breath sounds, RV heave, tender/smooth/pulsatile liver, and trace lower extremity edema.
What is the most likely cause?Mechanism? --------- Correct Answer -------- Longstanding pulmonary disease + right heart symptoms --> *cor pulmonale*
This is due to constant *hypoxic vasoconstriction* of the lungs, which places strain on the right heart.
(True or False)
Exogenous ingestion of an organic acid causes anion-gap metabolic acidosis --------- Correct Answer -------- *True*
Pt with a history of Crohn syndrome presents with 24 hours of severe abdominal cramps. Prior to this, he had 2 weeks of constipation. Physical exam shows signs of bowel obstruction. KUB shows no free air, but shows air-fluid levels.
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Most likely cause? --------- Correct Answer -------- *Small-bowel strictures* secondary to Crohn disease.
NOT intussusception (way rare in adults)
Pt presents with hemearthrosis after minor injury with increased PTT; normal BT and INR.
Most likely cause?What is normal bleeding time? --------- Correct Answer -------- Hemophilia A (*Factor VIII deficiency*)
2-7 minutes
Most common enzyme deficiency in congenital adrenal hyperplasia --------- Correct Answer -------- *21-hydroxylase*
Pt on lithium presents with polydipsia and polyuria. Labs show normal lithium, glucose,
and Cr levels. In addition:
- Serum Osm: 280
- UOsm: 200
After fluid restriction:
- Serum Osm: 295
- UOsm: 250
Most likely cause?Explain. --------- Correct Answer -------- Nephrogenic DI, or *resistance of kidneys to ADH/vasopressin*
Resistance to ADH results in *free water loss* and *inability to concentrate urine* (<200- 300 urine). In addition, urine Osm should rise after fluid restriction (more significantly than in this patient).
Marfan syndrome; grade 3/6 late systolic murmur following a click @ apex.
Becomes fainter and shorter with squatting. No diastolic murmur.
Most likely cause?Explain. --------- Correct Answer -------- *MVP*
An increase in preload due to squatting increases LV size, allows the choardae to keep tension and delay the prolapse, thereby delaying the click and decreasing the intensity of the click and murmur. (similar characteristics as HOCM, but *Marfan <--> MVP*)
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A young girl presents with significant upper extremity HTN for the first time and you suspect Turner syndrome.
Next step in evaluating her HTN? --------- Correct Answer -------- *TEE* to look for *coaractation*
Do not need to repeat BP measurements in this case.
Strongest risk factor for Alzheimer dementia --------- Correct Answer -------- Family history
12 days post liver transplant:
- Mononuclear infiltrate with significant eosinophils in the hepatic triads
Most likely diagnosis?*How am I going to remember this?* --------- Correct Answer -------- Allograft rejection (*acute*)
Remember:
*Hyperacute - thrombosis of graft vessels Chronic - proliferation/arteriolosclerosis*
Hyponatremia, serum Osm 250, and urine Osm 50 (this is very low)
Diagnosis? --------- Correct Answer -------- *Psychogenic polydipsia*
Tourette disorder
Age + timing for diagnosis --------- Correct Answer -------- Onset *before age 18* and motor and vocal tics that persist for *>1 year*
Kid presents with symptoms of increased ICP, cerebellar symptoms (vermis and peripheral), long-tract signs, and bilateral babinski.
Most likely cause (if malignant)?
- non-malignant --------- Correct Answer -------- Most likely *Medulloblastoma*
- Most common malignant brain tumor in childhood
*Pilocytic astrocytoma*
- Non-malignant, same location
HIV positive male presents with severe rectal pain, bleeding, and constipation. Physical exam shows 1.5cm mass at anal verge with central ulceration that is oozing blood.
Most likely diagnosis? --------- Correct Answer -------- *SCC*
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This is NOT a skin tag related to an anal fissure; way more serious presentation.
FEV1, FVC, and TLC in *asthma* --------- Correct Answer -------- FEV1 - decreased FVC - normal TLC - increased
Pt with SLE is pregnant.
Fetus is at greatest risk of what cardiac abnormality? --------- Correct Answer -------- *Complete AV block*
Patient presents with a 2-day history of fever and an area of tender, erythematous swelling on the forearm + red streaks that extend to the elbow + epitrochlear LAD. No wound or ulcer to be seen.
Most likely diagnosis?Other differential? --------- Correct Answer -------- *Lymphangitis* This is most likely erysepelas, which spreads through the dermal lymphatics (more likely to have systemic signs)
Other ddx: *superficial thrombophlebitis*
This is less likely
Teenager p/w SOB and pleuritic chest pain after being immobilized for 2 weeks. She's on OCPs. No tachycardia, but RR is 30, and POx 88. Small pleural effusion visualized on CXR.
Next best step? --------- Correct Answer -------- Spiral CT of chest
*Suspected PE*
Pt presents with pelvic injury after an accident.
Next best step? --------- Correct Answer -------- Assess for urethral injury with a *retrograde urethrography*
You suspect ankylosing spondylitis on clinical exam.
Best initial step in diagnosis? --------- Correct Answer -------- XR of the SI joints
*NOT measurement of ESR*
Type 1 diabetic comes in with low grade fever, HA, and facial swelling for a few days.PEx: tenderness over the maxillary sinus with CT showing opacification. Labs: mild ketoacidosis.
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