18 results
Approach to the A-a Gradient
A-a gradient = PAO2 - PaO2
A-a gradient = [FiO2 x (Patm -
Hypoventilation: CNS ... Hypoventilation Syndrome ... UnremarkableLab #AA ... Gradient #alveolar #arterial ... #hypoxemia #differential
CNS Ring-Enhancing Lesions - Immunocompromised vs Immunocompetent
Multiple Ring-Enhancing Lesions:
 • Toxoplasmosis (CD4 < 100)
 • Other
CNS Ring-Enhancing ... + toxo IgG • CNS ... 30% present w/ CNS ... @AnnKumfer #CNS ... #diagnosis #causes
Hyponatremia - Differential Diagnosis Algorithm
Hypovolemic - Give volume
Hypervolemic (Edematous) - Look for and treat underlying cause
Hyponatremia - Differential ... treat underlying cause ... cirrhosis, nephrotic syndrome ... Pulmonary Diseases ... , CNS Disease, Meds
Short Stature - Differential Diagnosis Algorithm
Normal Variant, Normal Puberty Onset (BA = CA)
 • Familial Short
Short Stature - Differential ... Anorexia Nervosa • CNS ... #ShortStature #Differential ... endocrinology #causes ... #pediatrics
Hyponatremia - Differential Diagnosis by Mechanism
Decr Blood Pressure (“Decr Effective Circulating Volume”) 
 - Volume depletion
Hyponatremia - Differential ... - Cirrhosis Syndrome ... the lung) - CNS ... hemorrhage) - Pulmonary ... Diagnosis #Table #Causes
Causes of Hypotonic Infant (Floppy Newborn) - Differential Diagnosis Algorithm
Central Nervous System - Decreased LOC, Axial
Causes of Hypotonic ... Floppy Newborn) - Differential ... Hemorrhage • CNS ... Other Congenital Syndromes ... #Peds #Pediatrics
Weakness - Differential Diagnosis Framework

Approach To Weakness:
 • Non-neuromuscular disorder (Cardiac, pulmonary etc)
 • CNS ->
Weakness - Differential ... disorder (Cardiac, pulmonary ... etc) • CNS -> ... , CMV, EBV - Bacterial ... #Weakness #Differential
Guillain–Barré syndrome (GBS)
(aka: Landry–Guillain–Barré–Strohl syndrome:
	Most common cause of acute flaccid paralysis
	Rapidly progressive ascending paralysis & areflexia
	Autonomic
Guillain–Barré syndrome ...  Most common cause ... Differential diagnosis ... Multiple Sclerosis: CNS ...  Transverse myelitis
Adie's Pupil
What? Unknown nature & benign
 • Regular and mildly dilated pupil (4-6mm);
 • Light-near dissociaton;
Holmes-Adie Syndrome ... Young females Differential ... Diagnosis: • CN ... dissociation • Other causes ... #Adies #Pupil #PhysicalExam
Acid Base Disorders - Blood Gas Interpretation

Steps for Blood Gas Interpretation: 
1. Acidemia or Alkalemia? 
2.
Differentials? ... D-lactate (short bowel syndrome ... , intestinal bacterial ... Classically” noted with pulmonary ... acidosis: - CNS