Mixed 14 Flashcards
Pathophysiology of Lactose intolerance.
Incomplete hydrolysis of lactose into glucose and galactose leads to its fermentation by gut flora. The increase in short-chain fatty acids acidifies the stool. Hydrogen gas is also produced, causing inc. breath hydrogen content. The undigested lactose also inc. stool osmolality, causing osmotic diarrhea.
What happens in Graft vs Host disease?
Donor T cells become sensitized to MHC on host tissues and subsequently attack them. The skin, liver, and GIT are frequently affected. This usually occurs in pts with bone marrow or liver transplant.
>Maculopapular rash that desquamates, intestinal bleeding, abd. pain, abnormal liver function tests.
Which anticholinestase agent can reverse both the CNS and peripheral ssx of Atropine toxicity?
> Physostigmine is a tertiary amine that can penetrate the CNS.
Neostigmine and Edrophonium have a quaternary structure that limits CNS penetration
What enzyme is deficient in Acute intermittent porohyria? What is the key feature of this disease? How do you treat AIP?
Porphobilinogen deaminase deficiency leads to accumulation of PBG and delta-ALA. A key feature would be reddish urine that darkens w/ exposure to light and air due to oxidation of excess PBG. Treatment would include giving heme and glucose to inhibit ALA synthase.
What drug may be used for chemoprophylaxis of meningococcal disease?
Rifampin can penetrate into all body compartments, including the URT, and will eliminate the nasopharyngeal colonization that occurs when inhaling respi secretions from a patient.
What is the presentation for Dermatomyositis? What would its muscle biopsy show?
> Skin: Gottron papules, heliotrope rash.
Muscle: proximal muscle weakness (difficulty climbing stairs, combing hair), inc. muscle enzymes.
Biopsy: perimysial inflammatory infiltrate and atrophy with CD4+ T cells.
