Self Assessment Flashcards
Stages of ARDS
Also called diffuse alveolar damage but starts with perialveolar endothelial damage
1) Exudative phase (fluids damage alveolar walls)
2) Proliferative phase (edema resolution and type II pneumocytes proliferation)
3) SOMETIMES fibrotic phase (diffuse pulmonary fibrosis and cyst formation)
Cardiac conduction speeds
His-Purkinje > atrial > ventricular > AV nodal
AV node located at interatrial septum near the right AV orifice
Osteosarcoma location and radiological findings
Femur > tibia > humerus
Sunburst pattern and Codman triangle
Globus hystericus
SAME as globus sensation
Feeling of difficulties swallowing despite negative radiological and endoscopic findings of dysfunction
Linked to emotional stress, psych disorders and GERD
Why gout causes flairs
Monosodium urate crystals normally covered with ApoE or ApoB protective coating
Fluctuation or trauma causes uncoating and antigenic exposure - > neutrophil activation and inflammation
Germline mosaicism
Suspect when disease present in offsprings but not the parents
Involves genetic mutations early in embryonic development
Osteogenesis imperfecta inheritance pattern
Autosomal dominant
Molluscum contagiosum infection
Children - through fomites (face, neck, trunk, axilla)
Adults - sexually transmitted (trunk, anogenital)
Immunocompromised - prolonged course and widely distributed papules numbering in the hundreds
Knee dislocation injury
Popliteal artery because it is closest to the articular surface and is bound proximally and distally by the adductor magnus and the soleus respectively
Penetrating injuries more likely to damage the tibial nerve
Most common bacteria in postpartum endometritis
Bacteroides species
Post-nephretomy recovery
Initial drop of 50% total GFR but quickly recovers to 80%
Vasomotor rhinitis
Chronic nasal congestion triggered by abrupt changes in temperature, humidity or strong odors (also comes with headache and sinusitis occasionally)
Nummular eczema
Associated with xerosis (dry skin) and exacerbated by environmental irritants
Typically presents as coin-shaped pruritic erythematous eruptions
Cocaine abuse
Atrophic nasal mucosa Nasal septal thinning Chronic nasal discharge Nasal septal perforations Osteolytic sinusitis Headaches
HSV encephalitis
Tends to affect the temporal lobe
Unique features include olfactory hallucinations, anosmia, personality changes, aphasia, delirium, bizarre behaviors, temporal lobe seizures and hemiparesis
AIP Inheritance pattern
Autosomal dominant
Defect in hydroxymethylbilane synthase (AKA porphobilinogen deaminase)
Urine darkens upon exposure to sunlight but person does not experience cutaneous photosensitivity
Diagnosis on the causes of pleural effusion
Light’s criteria (must mean at least one of three)
1) Ratio of pleural protein to serum protein > 0.5
2) Ratio of pleural LDH to serum LDH > 0.6
3) Pleural LDH is above 2/3 upper limit of serum LDH
Minor criteria
Pleural to serum albumin difference > 1.2 g/dL
Osmotic fragility testing for RBCs
Increased fragility in hereditary spherocytosis (due to decreased surface area to volume ratio)
Decreased fragility in thalassemias and sickle cell (due to
Echinocytes vs acanthocytes
Burr cells vs Spur cells
Echinocytes have smaller and more uniformly distributed spicules all around the perimeter of the RBC
Acanthocytes have bigger, fewer and more irregular spikes that are unevenly distributed on the RBC surface
Echinocytes
Usually a laboratory artifacts due to sample preparation
But can be associated with disease
1) Uremia
2) Pyruvate kinase deficiency
B12 and folate deficiency
Both are susceptible to depletion in alcoholics and elderly
B12 depleted over the course of years
Folate depleted over the course of weeks
While hematological abnormalities are reversible, B12-related neurological issues are IRREVERSIBLE
Folate supplementation alone without B12 when patient is B12 deficient can actually worsen demyelination and cause abnormal myelin synthesis
Multiple sclerosis shock
Lhermitte phenomenon
Shock-like sensation shooting down the spine radiating to the feet upon neck flexion
Paraneoplastic myasthenias
Myasthenia gravis = 60% thymic hyperplasia and 10% thymoma
Lambert-Eaton myasthenic syndrome = small-cell lung carcinoma (more extremities weakness vs axial/girdle and also typically older patient with smoking history)
Infective arthritis organisms by group
Children < 2 y/o = Hemophilus influenza B
Adolescents = Staph aureus
Teenagers and adults = Neisseria gonorrhoeae
Elderly = Staph aureus
Sickle-cell patients = Salmonella
DKA electrolytes
Glucose UP
Potassium UP
(Decreased insulin to drive K+ into cells; H+/K+ increased exchange in a-intercalated cells in the CCT; H+K+ increased exchange at cell membranes)
Sodium DOWN
(Despite hypovolemia and body trying to preserve sodium and water, the osmotic diuresis from glucose drags sodium and water out of the body; for every 100 mg/dL glucose increase, Na+ decreases 1.6 mEq/L)
Dandy-Walker syndrome
Cerebellar vermis absence or hypoplasia leading to trunk ataxia and abnormal coordination
Fourth-ventricular cyst leading to hydrocephalus and macrocephaly
Abnormally enlarged posterior fossa; can be associated with polydactyly, urogenital malformations and cardiac defects
Allelic vs genetic vs phenotypic heterogeneity
Allelic heterogeneity = different mutations in the same gene cause similar but different phenotypes
Genetic heterogeneity = mutations in different genes cause similar phenotypes
Phenotypic heterogeneity = mutations in the same gene causes different phenotypes
Bronzing in hemochromatosis
Autosomal recessive
Disease is usually not observed until over 20g total iron
Dermal hemosiderin deposits provides skin with bronze
Impotence, arthropathy, cardiac enlargement/dysfunction
Achondroplasia
Autosomal dominant inheritance pattern
Mutation in FGFR3 on Chr 4 (gain-of-function)
FGFR3 normally inhibits chondrocyte proliferation
Exceptions to the sympathetic postganglionic rule
1) Sweat glands (acetylcholine)
2) Arrector pilorum muscle (acetylcholine)
3) Renal vasculature (dopamine)
4) Adrenal medulla (acetylcholine)
Secretion mechanisms
Eccrine = merocrine (vesicular content release) Mammilary = apocrine (apical buds) Sebaceous = holocrine (entire cell buds off)
Platelet activating factor (PAF)
High doses 1) Vasoconstriction 2) Bronchoconstriction 3) Platelet aggregation and microthrombi formation Low doses 1) Vasodilation 2) Leukocyte adhesion and diapedesis 3) Degranulation and oxidative burst Acts through Gq and increases IP3
Red man syndrome
Rapid vancomycin infusion causes nonspecific mast cell degranulation that is NOT IgE dependent
Blue sclera
1) Osteogenesis imperfecta
2) Menkes syndrome
3) Progeria
Bile acid alternative function
Because they are amphipathic, bile salts also function to disrupt plasma membranes and is bactericidal
Patients with chronically blocked common bile ducts can develop bacterial overgrowth
Eukaryotic ribosomal subunits
80S total
60S = 28S, 5.8S and 5S
40S = 18S
28S+18S+5.8S transcribed from a single gene by RNA polymerase I and 5S transcribed separately by RNA polymerase III
Prokaryotic ribosomal subunits
70S total
50S = 23S and 5S
30S = 16S
Delusional disorder
Presence of “non-bizarre” delusions for more than one month. Non-bizarre delusions are those that are strange but nonetheless possible. Person has preserved social and occupational functioning.
If another person of close relation also has the same set of delusions, then it would be diagnosed as shared psychotic disorder.
Peripheral insulin resistance vs. impaired glucose tolerance
1) Peripheral insulin resistance means tissues respond poorly to insulin but increased pancreatic release is able to keep the blood glucose levels normal
2) Impaired glucose tolerance means that despite max pancreatic insulin secretion, blood glucose can rise to abnormally high levels
Lichen sclerosus and atrophicus
White plaques surrounding the vulvular area and skin thinning; caused by autoimmune inflammatory condition involving autoantibodies against ECM components
Pruritis, dyspareunia, pain on defecation
Can lead to disfigurement and squamous cell carcinoma
Treat with high-dose corticosteroids
ATN nephrotoxins
1) Aminoglycosides
2) Heavy metals
3) Radiocontrast
4) Amphotericin B
5) Myoglobin/hemoglobin
6) Bence-Jones protein
Prader-Willi syndrome
P = you NEED the paternal allele of chromosome 15
1) Hyperphagia
2) Neonatal hypotonia
3) Short stature
4) Small hands and feet
5) Hypogonadism
Dermatitis herpetiformis pathophysiology
Anti-gliadin IgA and IgG cross-reacts with reticulin, a component of fibrils needed to anchor the epidermis to the superficial dermis
Neutrophil recruitment leads to inflammation, edema and destruction at the dermal papillary tips and micro-abscess formation -> coalesce into subepidermal blisters
Callus layer
Callus is restricted to the stratum corneum
Puromycin
Aminonucleoside antibiotic
Mimics aminoacyl-tRNA and accepts the growing polypeptide chain and dissociates
Alternative causes of acanthosis nigricans
Benign conditions include insulin resistance and obesity
If the acanthosis has the following characteristics:
1) Sudden onset
2) Rapid spread
3) Affects mucosal surfaces and/or the palms and soles
The likelihood of an underlying GI tract malignancy or lung cancer is high (stomach, liver, intestinal etc)
Gaucher disease
Most common lysosomal storage disease
Most common genetic disorder in Ashkenazi jews
Autosomal recessive mutation in glucocerebrosidase
Aspergillus morphology
Acute angle septated hyphae
Occasionally forms “broom-like” structures called conidiophore project
Hand-food-genital syndrome
Mutation in HoxA13
1) Clinodactyly
2) Short thumbs
3) Small feet
4) Short great toes
5) Genitourinary defects (female: GU tract duplication; male: hypospadias)
Waardenburg syndrome
Mutation in Pax3
1) Heterochromia irides (different iris colors)
2) Poliosis (white patches of head hair, eyebrow or lash; also present in 60% of tuberous sclerosis)
3) Dystopia canthorum (lateral displacement of the medial canthus, giving the appearance of wide nose)
4) Deafness
Why maxillary sinus is the most commonly infected
The path of drainage for the maxillary sinus is above the floor of the sinus and thus unaided by gravity
