Saturday, May 12, 2012

Remember

Most senstive test for subarachnoid haemorrhage, SAH, is Lumbar puncture: shows xanthochromia

Tuberous sclerosis

-a neurocutaneous syndrome

Tubers in the brain

Ash leaf hypopigmented macules on the skin, more visible under uv light (woods lamp), facial angiofibroma, forehead plaques, periungual fibroma,

Retinal harmatoma

Presents in infancy with infantile spasms (seizures)  which may be confused with colic. (may be described as head bobbing, doubling up etc) Treat with ACTH

Dental involement (pits), lung involvement etc

Cardiac harmatoma

There may be learning disabilities, mental retardation or epilepsy.

Thursday, May 10, 2012

Bone lesion differentials

Osteoid osteoma:  radioluscent (lytic) centre,usually <1cm surrounded by sclerotic lesion. Benign

Brodie's abscess: form of osteomyelitis, remains subacute for years before converting to chronic (draining) osteo. radioluscent lesion >1cm surrounded by irregular margin of sclerosis. Benign

Osteosarcoma: hard irregular spiculated lesion (moth -eaten or sun burst appearance) with periosteal elevation- Codman's triangle, . Malignant. seen more commonly in Male adolescents. Most common primary bone cancer

Ewing's sarcoma: lytic lesion with periosteal reaction- onion skinning. Malignant. Highly metastatic.Typically seen  in Male adolescsent

Primary sclerosing cholangitis

Damage to both intra and extra hepatic bile ducts. ERCP or MRCP shows beading (segmental narrowing and dilatation)of both intra and extra hepatic ducts.

Anti smooth muscle antibodies (ASMA)(in 20%-50%), ANA, p-ANCA (not specific)

Young Man with itching, jaundice, malabsorption syndrome, signs of cirrhosis etc.

Biopsy may show periductal sclerosis (onion skinning)
Tmt: Ursodeoxycholic acid, cholestyramine, vitamin supplements



Note: ASMA and ANA + jaundice are also present in autoimmune hepatitis but Auto immune hepatitis is xterised by
female preponderance,
extrahepatic autoimmune diseases
hypergammaglobulinemia.

Treatment of autoimmune hepatitis is low dose steroids.

Primary biliary cirrhosis

interlobular bile duct destruction

itchy, yellow, middle aged woman with high alkaline phosphatase, normal transaminases, high GGT, high bilirubin and positive Anti mitochondrial antibodies, ANA

+signs of cirrhosis
Liver biopsy shows periductal mononuclear infilterate with bile duct destruction

Tmt: Ursodeoxycholic acid, cholestyramine (reduces itching)

no cure

Coronary artery bypass graft

Indicated in patients with CAD with angiography showing >70% stenosis of left main coronary artery or >70% stenosis of 3 or more vessels (2 or more vessels if diabetic)

Internal mammary artery graft preferred over saphenous vein graft (restenoses in abt 5 yrs)

Needle stick injury

Risk of infection:


HBV > HCV > HIV > Other organisms

Status Epilepticus

Seizure lasting 30mins or more
or
2 or more seizures occuring without interval recovery

TMT:
Benzodiazepine> phenytoin >more phenytoin >Phenobarb>more phenobarb>G.A + Intubate

Wednesday, May 9, 2012

Complications post MI

Sinus bradycardia : give atropine if symptomatic

3rd degree AV block:  Usually ffing Inf wall MI (ST elevation in leads II, III and avf) - bradycardia, there's independent contraction of RA and RV leading to Canon A waves (in Jugular). Treatment is pacemaker

Right Ventricle infarction: (also Inf Wall MI), RV dysfxn leads to reduced pulmonary bld flow, low preload, hypotension especially with nitrate use, tachycardia. Lungs are clear.Tmt is high volume fluid infusion. Avoid nitroglycerin
(vasodilator).

Ventricular fibrillation/tachycardia: loss of pulse, ECG findings. Tmt: defibrillation if no pulse

Reinfarction: recurrence of pain, new signs of pulmonary edema, new rise in CK-MB (Troponin is useless high cos level remains high for 10-14 days after initial infarction unlike CK-MB- 1-2 days) Tmt: As new MI

Free wall rupture: usually 2-8 days post MI when scars are forming but can occur as early as within the first 24hours, leads to cardiac tamponade, hypotension, JV distension, sudden loss of pulse. Do Echo. Tmt: emergency pericardiocentesis then surgical repair

Septal rupture: septal defect forms, new pansystolic (VSD) murmur hrd best at LLSB, pulmonary congestion, step up in oxygen saturation as you move from right atrium to right ventricle. Do Echo

Valve rupture: valvular insufficiency, mitral regurgitation, new systolic murmur heard best at apex radiating to axilla. Do Echo


edited: mechanical complications (rupture) can occur as early as the first day of MI although more common days and weeks after.

Snake bite

Rattle snakes are the leading cause of snake bites in the USA.
Bites are usually provoked, "intoxicated (drunk) young man who sees snake and still approaches it".

Symptoms
Local: swelling, severe pain, tingling.
Systemic: weakness, anxiety, nausea and vomiting, bleeding, perspiration,heart failure.
No local symptoms within 1 cm of fang marks after 1 hour - ? no or minimal envenomation 
No edema or erythema in the area of the bite after 6–8 hours = no envenomation

Treatment:
Local: splint or immobilise. DO NOT INCISE OR SUCTION BITE WOUND
Envenomation: Crotaline antivenom ("antivenin" )

Wegener granulomatosis

Upper resp disease + lower resp disease, + glomerulonephritis
Other signs of vasculitis on skin,eyes, joints etc

Best initial: c-ANCA
most accurate test: biopsy
(lung biopsy best)

Tmt: Prednisone +cyclophosphamide.



note: Good pasture has similar presentation but no upper resp involvement and anti GBM abs r present (Best initial test).
kidney biopsy shows linear deposits. No signs of systemic vasculitis unlike in Wegener's granulomatosis.

Treatment of inflammatory bowel disease

Acute exacerbations: steroids

Chronic maintenance: mesalamine
note: mesalamine is an active  metaboliteof sulfasalazine. Sulfasalazine was previously used but stopped due to side effects (agranulocytosis, hypospermia) from its other metabolite sulfapyridine.


Note:
For perianal disease, give ciprofloxacin+metronidazole
Colectomy can cure UC but is not routine tmt.
Crohn's usually recurs at surgery site





P.S :
IBD serology-  ASk Crohn ANd Call it !
ASCA- Crohn
ANCA- Colitis (ulcerative colitis)  specifically p-ANCA

pronounce the underlined as one sentence.

Most accurate test however is endoscopy

Treatment of heart block

First degree (prolonged PR) :
No treatment


Mobitz I (prolonged PR, longer PR, even longer PR then dropped beat, cycle repeats. could be 2:1,3:1, etc.):
Treat underlying cause


Mobitz II (Just dropped beats. Constant PR intervals,no prolongation of PR with subsequent beats as in in type I):
Pacemaker


3rd degree (No relationship between P and QRS waves and the P rate is faster than QRS rate):
Pacemaker

Atropine is used in first degree and Mobitz I if the bradycardia is severe or symptomatic.
IV Atropine is first line in any severe symptomatic bradycardia.

Tuesday, May 8, 2012

Treatment of stable angina

i.e angina precipitated by exertion, relieved by rest

Stable angina is as stable and simple as A, B, Cerine!

A- aspirin
B- beta blocker
C- nitroglycerine

Treatment of ST segment depression / Unstable angina

Aspirin (or clopidrogel or prasugrel): prevents plaque rupture

Heparin: prevents further growth of thrombus

then

Nitroglycerin
Morphine
Oxygen
Beta blockers
ACEi
GP2a/3b inhibitors


No mortality benefit from Oxygen, Morphine or Nitrates
No need for thrombolytics in non ST seg elevation event. Just prevent further elongation by giving heparin.

Treatment of STE Myocardial infarction (STEMI)

Aspirin (or if allergic, clopidrogel or prasugrel)

next

Angioplasty (door to balloon time 90mins) or if not available, thrombolytics (door to needle time: 30mins)
  • Angioplasty (PCI) is preferable to thrombolytics however in the absence of PCI, give thrombolytics preferably within 30mins of infarction, but can still be given up to  12hrs post MI
then

Beta blockers (if contraindicated then use CCBs)
ACEi/ARB (especially with ejection fraction <40%)
Oxygen
Statins (especially with LDL >100mg/dl)



WARFARIN IS USELESS IN MI TREATMENT
Heparin can be administered for a short time post angioplasty to prevent restenosing 

Monday, May 7, 2012

Treatment of Pulmonary embolism

1. Anticoagulation: Heparin + Warfarin. Stop Heparin after 5-7 days when Warfarin may've kicked in. Target is INR of 2-3

2. IVC filter:
if heparin is contraindicated
if recurrent embolic event even while on heparin or therapeutic Warfarin (INR 2-3)
if there's severe disease with right ventricular dysfxn and enlargement. The next embolus could be fatal so put a filter


3. Thrombolytics (t-PA- tissue plasminogen activator): if patient is too unstable or if there's RV dysfxn

Aspirin is useless in PE

Note: watch out for HITT with heparin therapy. - monitor cbc
HITT:
Patient on heparin
Thrombocytopenia
5-10 days after start of treatment
New thrombus or expansion of old one
Mgt: stop heparin, give thrombin inhibitor: Argatroban or lepirudin

Do not transfuse platelets in HITT

Sarcoidosis

African American, Woman
Dyspnoea
Erythema nodosum on legs
Hilar adenopathy, fibrosis on Cxray
lymph node biopsy shows non caseating granuloma
Granuloma may be producing vitamin D causing hypercalcemia, hypercalciuria
Restrictive pattern on PFT
Cardiac invovement: restrictive cardiomyopathy- diastolic dysfxn
Other features: enlarged parotids, facial nerve palsy, uveitis, hepatomegaly, CNS involement.

Tmt: Steroids (if symptomatic only)

Empirical antibiotics treatment

compiled for the purpose of preparation for the USMLE step 2

Bacterial Meningitis: Ceftriaxone+vancomycin+steroids+/- Ampicillin

Though no culture results yet, you would have done LP (xcept if contraindicated) so u have an idea if bacterial (wbc in thousands)
If immunosuppressed or neonate or elderly or alcoholic and gram stain yields nothing , add Ampicillin (for Listeria monocytogenes which r gram positive rods). However, if gram stain already shows gram positive cocci, Ampicillin will be unneccessary.
Don't use ceftriaxone in neonates, use cefotaxime
Steroids lower mortality in pneumococcal meningitis
If confirmed Neisseria meningitis, give Rifampicin or ciprofloxacin to close contacts, isolate patient.
If culture results yield susceptible pneumococci, stop vancomycin.


Otitis Media: Amoxicillin


Sinusitis: Amoxicillin (or trim/sulfa or doxycycline) + decongestant


Pharyngitis: Amoxicillin
Rapid strep test done in the office diagnoses strep pharyngitis within minutes so the tmt is not really 'empirical' so to speak
(for penicillin allergic pt: clindamycin or clarithromycin Or if allergy is only a rash, use cephalexin)


Severe infectious diarrhoea: Ciprofloxacin + fluids
Severe if: hypotension, fever, bloody diarrhoea, abdo pain or acidosis -in this scenario, suspect bacterial etiology

if mild infectious diarrhoea, give fluids only


Urethritis: Ceftriaxone (or cefixime)  + doxycycline (or Azithromycin)


PID: exclude pregnancy first and give Ceftriaxone+doxycycline (outpatient)
or if inpatient, cefotetan + doxycycline

If pregnant, substitute doxycycline with azithromycin or amoxycillin or erythromycin


UTI: ciprofloxacin
or Trim/sulfa or cephalexin in cystitis
(Nitrofurantoin in pregnancy)
or Ampicillin+gentamicin for Pyelonephritis
(with PyNeph, suspect abscess if persistent fever after 5-7 days of antibiotics, do Sonography or CT and drain)





Acute Prostatitis: Ampicillin+gentamicin
(Chronic prostatitis:Trim/sulfa *8wks)





Endocarditis: Vancomycin + gentamicin



Community acquired pneumonia:
As outpatient:
Azithro or Clarithromycin or doxycycline  (if existing comorbidities/previous antibiotics, give Levofloxacin)
As inpatient:
Levo or moxifloxacin or Ceftriaxone+azithromycin



Hospital acquired pneumonia (after >48hrs in hospital):
(Antipseudomonals)
Cefepime
Ceftazidime
piperacillin+tazobactam
Carbapenems



Lung abscess: Clindamycin or Penicillin
usually due to aspiration thus cover for anaerobes



Impetigo: (staph and strep)
mild-    Topical mupirocin or bacitracin or Repatamulin
severe- Oral doxycycline or clindamycin or Trim/sulfa

(some say topical alone is not enough!)


Erysipelas: (strep > staph),Cellulitis: (staph>strep)
mild:    oral dicloxacillin or cephalexin or if allergic, macrolide or clindamycin
severe: iv oxacillin or nafcillin or cefazolin or if allergic, clindamycin


Postpartum Endometritis:
Clindamycin + gentamicin


Spontaneous bacterial peritonitis:  Cefotaxime


edited 8/06/12

Countdown

21 days to go!


Starting kaplan Q bank today.
Finished UWorld Q bank (1.5) times 1 wk ago


Doing 2nd round MTB by Conrad Fischer


Doing targeted viewing of some Kaplan videos.



God is on my side, I can do this!