PT5 Flashcards
Ornithine transcarbamoylase deficiency
Most common urea cycle disorder; X-linked recessive; cannot eliminate ammonia - excess carbamoyl phosphate converted to orotic acid (so you’ll see inc. levels in blood and urine) - decrease BUN and increased ammonia levels in blood
If you cannot transport ornithine from cytosol to mitochondria, which substance should you restrict from diet?
Protein - you generate ammonia from AA (from protein degradation) and inability to metabolize ammonia into urea means you should restrict protein intake
Deficiencies of complement factors that form the MAC attack often experience recurrent infections by…
Neisseria species
DiGeorge syndrome
Congenital absence of thymus and parathyroid glands caused by maldevelopment of 3rd and 4th pharyngeal pouches - results in pure T-cell dysfunction (T-cell lymphopenia) and thymic hypoplasia. You see recurrent viral and fungal infections (lack of T-cells) and hypocalcemia (no PTH) - tetany
Chronic granulomatous disease
Example of deficient intracellular killing; X-linked immunodeficiency that results from inability of phagocytes to synthesize NADPH oxidase - an enzyme essential for lysosomal oxidative burst.
Sx: recurrent infections with catalase+ organisms (ex: Staph)
Formula to calculate confidence interval limits
Mean +/- 1.96*SD/sqrt(n)
Clinical use for TCAs
Major depression, OCD, fibromyalgia, painful diabetic neuropathy
Side fx of TCA’s
Sedation, alpha-1 blocking effects (hypotension), anti-cholinergic (tachycardia, urinary retention, dry mouth)
Tri-C’s = convulsions, coma, cardiotoxicity
Treatment: NaHCO3 for cardio toxicity
PCP MOA
hallucinogen; inhibits NMDA receptor activation; can cause feelings of detachment and distance; slurred speech, ataxia, nystagmus, paranoia, hallucinations, hostile, aggressive
What type of necrosis is seen with hypoxic injury to the CNS
Liquefactive - infarct releases lysosomal enzymes and phagocytic cells migrate to remove necrotic tissue (leaving cystic cavity) which then becomes surrounded by astrocytes to form scar (gliosis)
HIV+ female brought to ER with new onset tonic-clonic seizures and MRI shows spherical lesions with surrounding edema in right frontal lobe - diagnosis & treatment?
Toxoplasmosis (T. gondii) -cat is the host for this - HIV individuals can develop ecephalitis with necrotizing brain lesions - results in fever, headache, altered mental status and seizures; you see RING-ENHANCING LESIONS in both hemispheres
Rx: pyrimethamine & sulfadiazine
Presentation fo P. jirovecii
Pneumocystis pneumonia (PCP) - diffuse interstitial pneumo; bilateral CXR appearance; disc-shaped yeast on methenamine silver stain
Rx: TMP-SMX, dapsone, can use Amphotericin to treat cryptococcal meningitis
Two most common cause of focal brain lesions (ring-enhancing lesions) in HIV+ patients
- Toxoplasmosis
2. Primary CNS lymphoma (B-lymphocytes)
What is used to treat emergent acute coronary syndrome
Beta blockers
Reserpine MOA
inhibits dopamine entry into presynaptic vesicles - this reduces BP and HR - is not used to treat acute coronary syndrome
Pinealoma
Typically seen in children, most often they are germinomas, cause obstructive hydrocephalus, Perinaud syndrome, precocious puberty (stim. beta-hCG)
Vitamin A toxicity
Acute: nausea, vomiting, blurred vision
Chronic: alopecia, dry skin, hepatotoxicity, hepatosplenomegaly, visual problems, papilledema
Niacin deficiency
Pellagra: dementia, dermatitis, diarrhea, death
B12 deficiency
pernicious anemia, anemic, icteric, smooth shiny tongue (atrophic glossitis), shuffling, broad-based gate, mentally slow
Excess vitamin C
can give false negative stool guaiac results associated with diarrhea and abdominal bloating
Propionic acidemia
poor feeding, vomiting, lethargy, anion gap acidosis - breakdown of valine, threonine, methionine, cholesterol, leads to formation of propionic acid which then is converted to methylmalonyl CoA
Primary cause of lacunar infarcts
Hypertensive arteriolar sclerosis forming micro clots (microatheromas)
First line therapy for generalized anxiety and panic disorder
SSRI (ex: paroxetine) - but this takes a while to work (~4 wks) - so you can sometimes add a benzo in that waiting period to further reduce anxiety/panic
Short-acting benzos
Triazolam, Alprazolam
