NBME-29 Flashcards
What unique physical finding will be found in lung consolidation (pneumonia, pulmonary edema)
Increased tactile fremitus (vibration against the hand) over the consolidated area of the lung.
Edema specific to parts of the body that that are influenced by gravity, such as your legs, feet, or arms
Dependent edema
Intestinal absorption of calcium (and also phosphate) is regulated (increased) by
Vitamin D (active form)
How does active vitamin D increase GI absorption of calcium and phosphate?
via calcium-binding protein “Calbindin”
Describe Vitamin D activation
- 7-Dehydrocholesterol –> Cholecalciferol
- converted by UV light in the skin - Two steps of hydroxylation
- first in the liver by 25-hydroxylase
- second in the kidney by 1a-hydroxylase - Formation of 1,25-dihydroxycholecalciferol (active Vitamin D)
Bile acids are synthesized mainly from
cholesterol
The body’s “primary” source of cholesterol excretion although 90% of it are reabsorbed through the intestine and recycled by the liver
bile acids
Bile acid resins is used to treat hypercholesterolemia through what MOA?
Bile acid resins prevents the reabsorption of bile acids from the intestinal lumen –> decreased intrahepatic cholesterol –> upregulation of hepatic LDL receptors (to restore intrahepatic cholesterol concentration) –> decreased serum level of LDL
Demyelinating polyneuropathy caused by autoimmune antibodies against peripheral nerve myelin
Guillan-Barre syndrome
Guillan-Barre syndrome is often preceded by an infection caused by
Camp. jejuni
Guillan-Barre syndrome presents with what symptoms/signs?
acute symmetrical muscle weakness, hyporeflexia or absent of deep tendon reflexes (LMN dysfunction), autonomic dysfunction (BP fluctuations, cardiac irregularities), and sensory deficits (pain, vibration, etc.)
A condition often following a viral illness and presents with thrombocytopenia, and petechiae/purpura and easy bruising due to autoimmune antibodies attack against Gpllb/IIIa on platelets
Immune Thrombocytopenic purpura (ITP)
Thrombocytopenia in ITP is caused by
peripheral destruction of platelets by macrophages in spleen (phagocytose the platelet-antibody complex)
BM Biopsy of ITP shows
- Increased # of Megakaryocytes
bleeding time bleeding time (BT), PT, and PTT of ITP
BT: prolonged
PT: normal
PTT: normal
- platelet itself is normal so PT and PTT is normal
Tx for ITP
Usually self-limited; steroids/immunosuppressants for chronic ITP
What medication can exacerbate asthma, respiratory symptoms (bronchospasm), and nasal polyps?
Aspirin (NSAIDs)
- The diagnosis: Asprin (or NSAIDs)-exacerbated respiratory disease (AERD)
Describe Arachidonic acid pathways (AA to P, P, T eicosanoids)
- Phospholipids (membrane) –> Arachidonic Acid
- by Phospholipase A2 - AA –> Cyclic endoperoxides
- by COX 1 & 2 - Cyclic endoperoxides –> P, P, T
- Prostacyclin (PGI) by prostacyclin synthetase
- Prostaglandin (PGE) by prostaglandin synthetase
- Thromboxane (TXA) by thromboxane synthetase
Describe Arachidonic acid pathways (AA to L eicosanoid)
- Phospholipids (membrane) –> Arachidonic Acid
- by Phospholipase A2 - AA –> 5-HPETE
- by 5-Lipoxygenase - 5-HPETE –> Leukotrienes
- by leukotrienes synthase
What NSAIDs nonselectively and irreversibly inhibits COX 1 and COX 2?
aspirin
Leukotrienes can increase bronchial tone and cause
bronchospasm
Medications that cause muscular paralysis (diaphragm paralysis) via competitive antagonism at the POSTsynaptic acetylcholine receptor sites in the neuromuscular junction
Nondepolarizing neuromuscular blocker (-curarine, -curonium, -curim)
Muscular paralysis can be treated with _____, as in myasthenia gravis
acetylcholinesterase
- Neostigmine
- Pyridostigmine
Because of its unopposed estrogen stimulation of the endometrium, Tamoxifen or SERMs increases the risk for what cancer?
Endometrial Hyperplasia/cancer