All posts by vmcimchiefs
APML – 12/5/17
- Makes 5-20% of AML cases and accounts for 600-800 cases per year in the US
- Higher incidence in people from Mexico, Central America, South America, Italy, and Spain
- Uncommon < 10 years old and > 60 years old
- Considered a medical emergency due to a high rate of mortality from hemorrhage
Labs will show:
- Pancyctopenia (one of the few leukemias that classically can present with a low WBC)
- Peripheral smear with promyelocytes and high nucleus to cytoplasm ratio with granules
- Coagulopathy (frequently with DIC)
- FISH with t(15:17) translocation
Treatment
- ATRA – start immediately even before diagnosis is confirmed given high rate of mortality without treatment
Consequences of ATRA
- ATRA differentiation syndrome – presents with SOB and volume overload – can occur at week 1 of treatment or up to 3-4 weeks after – treatment is dexamethasone and patient can be continued on ATRA
- Pseduotumor cerebri – look for in patients with high ICP – pathophysiology due to ATRA causing a hypervitaminosis A type syndrome – do LP to check ICP
Platelet transfusion goals
- > 100 for NSG procedure
- > 50 for bedside procedure or surgery
- >10 for anyone without bleeding to prevent spontaneous bleeding
Cannabinoid Hyperemesis Syndrome – 12/07/2017
Cholangitis – 12/05/2017
Aortic stenosis – 12/4/17
Most common etiologies of AS
- Calcification of a normal aortic valve overtime with age
- Bicuspid aortic valve
- Rheumatic heart disease (usually associated with mitral valve disease)
Symptoms
- Dyspnea (most common)
- Angina
- Syncope
Diagnosis
- Physical exam
- Systolic ejection murmur at RUSB with radiation to the carotids
- Any maneuver that decreases blood flow across the valve will cause a decrease in the sound of murmur (e.g. valsalva, handrip, or standing) whereas anything that increases blood flow across the valve will increase the sound of the murmur (e.g. squatting)
- Transthoracic echo
- Severe AS is AVA < 1 cm2, mean gradient greater or equal to 40, or max velocity greater than 4 m/s
Low-flow, low-gradient AS
- If patient has an AVA < 1 cm2 but has a mean gradient < 35 mmHg, consider low-flow, low-gradient AS
- To determine whether there is an intrinsic problem with the valve versus a pseduo-aortic stenosis due to myocardial dysfunction, do a dobutamine stress echo
- If AVA remains unchanged and the mean gradient increases with dobutamine, the etiology is severe AS and the patient would benefit from valve replacement
- If the AVA increases and the mean gradient doesn’t increase, this is a pseudo-aortic stenosis and the patient can be managed medically
When to treat?
- Any patient who is symptomatic
- An asymptomatic patient with EF < 50 or who is getting another cardiac surgery
Treatment
- AVR > TAVR if the patient is a surgical candidate
- TAVR is good for high risk patients and has similar survival to AVR in high-risk patients
- AV balloon valvuloplasty is a short-term bridge to TAVR as it only lasts a few months
- Medical management is usually not beneficial if a patient has severe AS
Giant Cell Arteritis – 11/28/2017
Aspirin toxicity – 11/22/17
Mechanism of action:
- Prostaglandins, prostacyclins, and thomboxane cause direct gastric mucosal injury
- Stimulation of chemoreceptor trigger zone in the medulla causes nausea/vomiting
- Activation of the respiratory center in the medulla causes hyperventilation and respiratory alkalosis
- Interference with cellular metabolism (Krebs cycle and oxidative phosphorylation) causes metabolic acidosis
Clinical features
- Tinnitus
- Vertigo
- Nausea and vomiting
- Diarrhea
- Hyperpnea (tachypnea and hyperventilation)
- Hyperthermia (due to disturbances with oxidative phosphorylation)
- Lethargy and confusion
Diagnostic tests
- Serum ASA level < 30 = therapeutic; > 40 = toxic; > 100 = absolute indication for HD regardless of symptoms
- Check K (goal is to prevent both hypo AND hyperkalemia), Cr (renal failure may indicate a need for HD), lactate (can increase due to direct cell injury), and PT (ASA can cause coagulopathy)
Treatment goals
- Keep salicyclate (which is a weak acid) in it’s charged and deprotonated form to prevent it from crossing into the blood brain barrier by maintaining alkalemia
Management
- ABCs – only intubate if evidence of HYPOventilation
- Activated charcoal if patient awake and oriented
- Sodium bicarbonate to keep urine pH ~ 8 and serum pH alkalotic and pH < 7.6 (still give bicarb even if evidence of alkalosis as long as pH < 7.6)
- IVF
- Prevent hypokalemia and HYPERkalemia because hyperkalemia can cause increase H secretion into the blood through the kidney H/K transporter which causes acidosis
- Glucose if altered mental status as neurohypoglycemia can be caused by ASA overdose despite a normal serum glucose level
- No acetazolamide because while that increases urine pH it causes increased H to be secreted into the blood causing acidosis which promotes the uncharged form of ASA which is toxic
Neurosyphilis – 11/21/2017
Panhypopituitaryism and adrenal crisis – 11/20/17
Remember that prolactin is inhibited by dopamine!
In panhypopituitaryism, the anterior pituitary hormones are more commonly affected than the posterior pituitary hormones and there is a spectrum for how much of the HPA axis is still preserved depending on the etiology of the panhypopituitaryism.
The hormones that need replacement in adults are T4 and cortisol. Testosterone can be replaced if needed in men. Estrogen and progesterone can be replaced in pre-menopausal women who do not want fertility at that time or in post-menopausal women to relieve post-menopausal symptoms. If a woman desires fertility and has enough HPA axis preserved then patients can get pulsatile GnRH to stimulate FSH and LH production to induce ovulation.
To screen for adrenal insufficiency, check a morning cortisol at 8am.
- Cortisol < 3 = likelihood high – check ACTH to determine primary versus secondary adrenal insufficiency
- Cortisol 3-18 = indeterminate – do further stimulation testing
- Cortisol > 18 = likelihood low – pursue other diagnosis
Stimulation tests
- Cosyntropin test – give cosyntropin (synthetic ACTH) and then measure cortisol level 1 hour later – normal is cortisol level > 18; if less than that, then likely primary adrenal insufficiency
- Insulin induced hyperglycemia test – give 0.1U/kg of insulin and check glucose at 15, 30, 60, 90, 120 minutes. Once glucose reaches < 50 then cortisol should be > 18
- Metyrapone testing – blocks 11B hydroxylase which leads to a drop in cortisol and increase in ACTH and increase in 11-deoxycortisol
Adrenal crisis
- Etiologies
- Insufficient dosing of steroids
- Failure to increase dosage of steroids with acute illness
- Persistent vomiting or diarrhea causing malabsorption of steroids
- Can commonly see isolated ACTH presentation in panhypopituitaryism
- Treatment
- Dexamethasone if adrenal insufficiency not yet diagnosed because it does not interfere with cortisol testing
- Hydrocortisone if pre-existing diagnosis
Remember – if you suspect adrenal insufficiency, give stress dose steroids immediately without waiting for further testing!
Cholangiocarcinoma – 11/15/2017
SCVMC IM Chief Resident Blog 