1. Empiric management of endocarditis: 

- Native valve: pen + gent. 

- Native valve, IVDU: nafcillin + gent to cover MSSA. vanc + gent if suspicion for MRSA

- Mechanical valve: cover MRSA, add rifampin for biofilm penetration 

- Replace vanc with linezolid if there is renal failure (issues with vanc levels) 

- Viridians strep endocarditis - IV penicillin continuous or q4-6 or once daily ceftriaxone for 4 weeks 

2. Don't treat HIT with Coumadin-- the rapid drop in protein c can aggravate the procoagulant state. Manage with argatroban or bivalrudin until platelets are > 150K, then you can start warfarin 

3. Some words on some drugs: 

- Bactrim covers s pneumo but not other strep species 

- Sodium bicarb blocks the effect of TCA on fast Na channels in cardiac tissue, hence the protective effect in overdose. 

- NSAIDs potentiate ADH and can lead to SIADH.

- Statins decrease  coenzyme q10 synthesis which is important for muscle energy - thought to be a possible etiology of the myositis. 

- Aspirin can trigger bronchoconstriction

- Alcohol sensitizies you to hypomagnesemia, increasing risk of torsades. 

- Drugs that prolong the QT: quinolones, macrolides, TCAs, class III antiarrhythmics 

4. Hemochromatosis 

- bronze DM

- hepatomegaly or cirrhosis (this disease is often diagnosed initially as incidentally raised LFTs on routine labs) 

- small testicle/decreased libido

- cardiac disease (dilated or restrictive myocarditis, conduction problems)

- Increased vulnerability to infections with listeria and vibrio vulnificus 

5. Splenic abscess

- Occurs in the setting of infective endocarditis (10-20% incidence?), immunosuppression (HIV), trauma, hemoglobin disease like sickle cell, IVDU. 

- Staph, strep, salmonella

- With antibiotics alone, there is a  50% mortality. Need splenectomy or percutaneous drain if they are too sick to go through surgery. 

6. Retropharyngeal abscess 

- Symptoms: trismus (pain w opening mouth), pain on neck extension, fever 

- Often history of local trauma (fishbone in throat) 

- Can dissect down into anterior or posterior upper mediastinum or all the way down the posterior mediastinum and cause necrotizing mediastinitis (requires urgent surgical debridement) 

- Vs: Meningitis, which has pain with neck flexion 

7. Back pain red flags

- Pain at night, not relieved by rest, not worsened with movement. 

- Bone that is tender to palpation, symptoms lasting > 1 month, age>50, 

- Get X-ray to r/o lytic lesion vs fracture, MRI if not diagnostic 

- Manage acute back pain with NSAIDs- acutely its better than PT. 

8. Acanthosis nigricans- DM or GI cancer

- More likely benign - young, obese person

- More likely malignant - older age. atypical locations such as mucous membranes, palms, soles

9. O2 supplementation in COPD: 

- In chronic COPD, people develop chronic hypercapnia and increased levels of deoxyhemoglobin, which has a higher CO2 affinity and increases carbon dioxide clearance. Adding oxygen blunts the amount of deoxyhemoglobin, decreasing clearance of CO2. 

- Acute hypercapnia: less myocardial contractility, lower seizure threshold, global loss of consciousness 

- Goal saturation for treatment of acute on chronic COPD with oxygen is 90-94% 

10. Polycythemia vera 

- causes gout in up to 40% of people 

- characteristic pruritus after a hot bath due to increased histamine released from increased basophils-  - - increased histamine secretion can also lead to gastric ulcer