Block 6 Flashcards
Cardiac cauterization in aortic stenosis patient
Normally the aorta and left ventricle have a similar pressure or very close, however in case of aortic stenosis patient a pressure gradient is present between these pressures. (See pic)
Intracranial schwannoma (Signs and pathology)
- most commonly located in the cerbell-opontine triangle, which is found between the cerebellum and lateral pons.
- bilateral schwannomas are associated with NF2
- acoustic schwannomas, arises from CNVIII, facial nerve and trigiminal nerve are close to CN VIII so they may get affected as well.
- impairment of cochlear portion –> sensorineual hearing loss and tinnitus
- compression of CN V may cause loss of facial sensation and loss of afferent limb of corneal reflex, also paralysis of mastication muscle.
- CN VII involvment can result in facial muscle paralysis (upper and lower) , loss of taste in anterior 2/3 of tongue and decreased lacrimation and salivation.
sulfonamide mechanism
PABA inhibitor (inhibit folic acid synthesis in bacteria).
Causes of erectile dysfunction
- psychogenic stressors
- performance anxiety or depression
- medication (SSRI, sympathetic blockers)
- vascular or neurological impairment
- genitourinary trauma (prostatectomy)
Uniparental disomy
Angelman and pardar willi syndrome
-two copy from one parent
Unomplicated umbilical hernia , clinical features and associated conditions
- pathology : defect at linea alba covered by skin –> incomplete closure of umbilical ring
- clinical : reducible bulge at umbilicus, notably with increased abdominal pressure (eg, crying, passing bowel movment)
- associated conditions : 1. Down syndrome. 2. Hypothyrodism
3. Beckwith -wiedemann syndrome.
Aplastic anemia after infection can occur with
B19 in sickle cell anemia or immunodefcient patients
Almetuzumab
Anti- CD52 used for CLL treatment. On binding to CD52. It initiate direct cytotoxic effect through complement fixation and antibody dependent cell mediated cytotoxicity.
H.pylori associated lymphoma
MALT lymphoma
Right margianl artery supply
Anterior wall of right ventricle
Pulmonary blastomycosis is characterized by
- granuloma formation.
- extra-pulmonary disease may occur in immunecompromised patients.
- round yeast with thick walls and broad based budding.
- itraconazole is preferred TX
TTP
Thrombotic thrombocytopenia purpura and hemolytic uremic syndrome( HUS). Are two points on a disease spectrum charactrized by the pentad microangiopathic hemolytic anemia.
TTP often occurs in adults with CNS involvment, while HUS in children with renal involvement. They dont bleed as coagulation factors level as are always normal, but the main problem is in platelets.
Disseminated intravascular coagulation after sepsis
Particulary in gram negative infection. DIC occurs due to exposure of blood to procoagulants that initiate intravascular thrombosis. Which is followed by compensatory thrombolyisis. The results is consumption of coagulation factors, coagulopathy and bleeding.
It should be suspected in patients with elevated PT,PTT , low fibrinogen levels, low platlets and high D-dimer
Turner syndrome occurs due defect in
Meiotic non disjunction
Ectopic pregnancy
- most common site -> ampulla–> appears as adnexal mass on ultrasound
- Risk factors include : tubal pathology(infection or surgery as tubal ligation).
- pregnancy after permanent sterilization is rare but 1/3 of cases are ectopic if implantation occurs.
- in ectopic pregnancy, uterine specimen would reveal “decidualized endometrium only, consistent with dilated, coiled endometrial glands and vascularized edematous stroma”, however embryonic or trophoblastic tissues will be absent from uterus .
Folic acid pathway
Folic acid –> DHF –> THF –> 1C donors –>thymidylic acid/amino acid synthesis/ purines.
P.vivax and p.ovale dormant liver treatment
Dormant liver forms called hypnozoites require additional primaquine therapy
Amiodarone
Class III anti arrhythmic drug used for management of supra-ventricular and ventricular arrhythmia. Class III predominantely block K+ channel and inhibit outward potassium current during phase 3 –> prolongs repolirization –> prolongs QT interval.
B-ALL
-fever ,malaise, bleeding, bone pain, and hepatosplenomegaly, generally B cell, ALL isnt associated with mediastinum compression symptoms
Antimitochondrial antibodies are seen in
Primary billiary cirrhosis
Diagnoal artery supplies
Anterolateral wall of left ventricle
Medulloblastoma
Arises in posterior fossa, present with symptoms of increased ICP and cerbellar dysfunction (dizziness, ataxia, nystagmus)
Budesonide
Glucocorticoids with potent anti inflammatory activity.
Wegeners disease
C disease: lung, kidney and nasopharynx
Associated with C-anca. It may target neutrophil proteinase 3
Endometrial shedding after menustral cycle is a
process of apoptosis
MAO inhibitors mechanism of action, and adverse effect
- they block monamine degredation
- hypertensive crisis after eating food containing tyramine
- tyramine is usually metabolized by MAO in GI.–> these medication also blocks MAO in the GI–> tyramine values increased –> hypertension.
Gerstmann syndrome:
- affects the dominant parietal lobe. Affects the angular gyrus. Brain region that is supplied by MCA. Its part of parietal association cortex.
- signs: finger agnosia, agraphia, acalculia and left to right disorientation.
Monamine are
Serotonin and NE
Stroke in dorsolateral thalamus
- contralateral hemisensory loss
- weeks to months later pts develops thalamic pain syndrome on the side of deficit.
Wallenberg syndrome
Ischemia to dorsolateral medulla, area supplied by PICA.
- loss of pain and temp in ipsilateral face and contralateral body(damage to spinothalamic and spinal trigeminal).
- ipsilateral bulbar muscle weakness (nucleus ambigous)
- vertigo( vestibular nuclei)
- ipsilateral limb ataxia (inferior cerberal pudencle)
- horner syndrome( descending sympathetic fibers)
Homogentisic acid oxidase deficiency
Alkaptonuria
-AR disorder of tyrosine degradation – > accumulation of large homogentisic acid –> hyper-pigmentation and degenerative joint disease
Drugs that cause impotence
- SSRI and
- clonidine
- methyldopa
- beta blockers
- amiodarone
Burkett lymphoma causes and association
Associated with EBV.(infection present in 40% of pts). Especially in immuncomprimised patients
-t(8,14) translocation which causes overexpression of c-MYC, transcriptional regulator that controls cell proliferation.
HHV 8 can cause
- kaposi sarcoma
- primary effusion lymphoma (B-cells) , with large cells , big nuclei and prominent nucleoli
Nutrient deficiencies in malabsorption
- Protein: muscle wasting,edema
- Fat: weight loss
- Iron,folate,b12: anemia
- Calcium,vitamin d: bone pain, muscle weakness, tetany
- VIT A hyperkeratosis,nyctalopia.
- VIT K: Petechiae easy bruising
Cardiac catheterization
Its performed to evaluate for cardiac etiologies and obtain direct measurements of intra-cardiac pressure in patients with unexplained symptoms.
- in general Right sided pressure are lower than left.
- the location of the catheter tip is determined by pressure reading
- PA = 6-12 mm Hg diastolic, 15-30 systolic
- right atrium = 1-6 mm Hg
- right ventricle= Diastolic 1-6 mm Hg and systolic 15-30 mm Hg
- left atrium/PCWP/LVEDP= 6-12 mm HG
- left ventricle = systolic = 90-140 mm HG diastolic 6-12
Pineal tumor signs
- obstructive hydrocephalus
- Increased ICP (headache, vomiting, altered mental status)
- parinaud syndrome –> upward gaze palsy
Trinucleotide repeatss
CGG - frgaile X
CAG - huntington
CTG - myotonic dystrophy
ALL clinical manifestations
Fever, fatigue ,pallor, petechiae and bleeding .
Leukemic spread can cause lymphadenopathy, hepatosplenomegaly and bone pain.
-T-cell ALL is more likely to present with large anterior mediastinal mass that compresses the esophagus (dysphagia) and trachea (dyspnea)
-B and T cell differentiation is done using cell surface markers
CD-10 ,CD-19,CD-20 :- pre B
CD2,3,4,5,7,8 :- pre T
Obesity hypoventilation syndrome (OHS)
- Chronic fatigue, dyspnea, difficulty concentrating, and increased PaCO2 in the setting of obesity.
- OHS result in pathophysiologic changes that includes increased production of CO2 due to increased mass and surface area, sleep disorder breathing and reduced lung volume and compliance
Tissue factor is
Thromboplastin
vWD disease
Blood profile- increased bleeding time. Increase PTT and decreased factor VIII levels.
- bleeding from mucosal surfaces and easy bruising
- excessive epistaxis or menustration
Drugs that known to be directly toxic to nerves include
Chemotheraputic agents that inhibit microtubule formation
Vincristine and paclitaxel
Bupropion is contraindicated in
Anorexia and bulemia patients
IgE independent mast cell degranulation.
- patients with acute pruritus following administration of morphine most likely has medication induced IgE independent mast cell activation.
- number of medication including, opoids, radiocontrast agents and some antibiotics like vancomycin can induce mast cell degranulation by activation of protein kinase A and PI3 kinase–> histamine relesase,along with bradykinin, heparin… –> symptoms include diffuse itching and pain, bronchospasm and urtecaria
Cherry red skin
CO intoxication
Friction rub, chest pain improved by leaning forward, pleuritic chest pain, recent myocardial infarction history
-peri-infarction febrenous pericarditis –> symptoms are treated with aspirin in combination with colchicine.
Cardiac tamponade
Etiology
Clinical signs
Diagnosis
Etilogy :
1. Malignancy ,radiation therapy
2. Infection
3. Drugs
4. Connective tissue disease (SLE, RA)
Clinical sign: Becks triad : jugular vein distended, hypotension and diminshed heart sound ,
- pulsus paradoxus ( abnormally large inspiratory decrease in systolic BP)
Diagnosis : ECG: low voltage QRS, electrical alternans
Chest X-ray: enlarged water bottle shaped heart, clear lungs
ACE inhibitors use in pregnancy can lead to
Potter sequence
As low AGII levels can result in fetal renal maldevelopment which in turn leads to reduced diuresis and oligohydroamnios.
- low AGII levels may result in impaired cranial vascularizaion and hypocalvaria (skull bone hypoplasia)
Interaction between nitrates and phosphodiesterase inhibitors
May lead to severe hypotension due to accumulation of CGMP.
Nitrates –> NO–> increase CGMP as a second messenger–> vascular smooth muscle relaxation.
Aspirin mechanism
Its NSAID that irreversibly inhibits COX-1 and COX-2 via acetylation, preventing conversion of arachidonic acid to prostaglandinds, prostacyclin and thromboxane.
- COX-1 actylation inhibits generation of Thromboxane A2
- COX -2 actylation blocks prostaglandins production in inflammatory cells, resulting in anti-inflammatory, anti-pyretic and analgesic effect.
Tyrosinase deficiency
Albinism
Scarlet fever signs
- Fever,chills and a rash. Sore throat
- Erythmatous rash on chest and abdomen that blanches with pressure
- gray-white tonsilar exudate and red bright tongue
- rash begins : scarlet spots or blotches –> sunburn with goose pimples (sandpaper like rash) – > desqumation may occur after a week
Conus artery supplies
Anterior area of IV septum and conus of pulmonary area
Bilateral occipital lobes can result
in cortical blindness, these patients may confabulate and deny it despite obvious deficit.
Bevacizumab
Monoclonal antibody, interferes with VEFG receptor activation –> inhibits angiogenesis
Incomplete recanalization of fetal intestinal tract results in
Duodenal atresia
Galactose metabolism disorders
- Galactose-1-phosphate uridyl transferase: jaundic, vomiting, hepatomegaly, renal dysfunction(aminoaciduria, and hyperchloremic metabolic acidosis) , E.coli sepsis, cataracts, hemolytic anemia.
- Galactokinase deficiency: cataracts, rarely pseudotumor cerebri.
Torsades de pointes -> drugs that causes it
Prlonged QT is associated with it. Amiodarone has a very low risk of inducing it unlike other anti arrhythmic. (Procainamid) A: anti Arhythmic (class IA,III) B: anti Biotics (macrolides ) C: anti C(P)ychotic : haloperidol D: anti Depressants (TCA) E: anti Emetics (ondansetron)
Dopamine hydroxylase deficiency
Its the enzyme that catalyzes the biosynthesis of NE from Dopamine.
Deficiency in this enzyme ledas to rare form of dysautonomia –> ptosis, orthostatic hypotension, hypoglycemia and hypothermia.
Fc region in immunoglobulin
It bind to the FcR (receptor) found on the surface of macrophages, neutrophils and B-lymphocytes.
This binding is essential for the process of opsonization.
- opsonization refers to the promotion of phagocytosis of tagged material by phagocytic cells such as neutrophils and macrophages.
-IgG acts as opsonin by binding antigen at its Fab sites and binding phagocytes at its Fc site.
Mechanical complication of acute MI (4)
- Right ventricular failure –> acute –>hypotension, clear lung and kussmaul sign
- Papillary muscle rupture –> 3-5 days –> acute severe pulmonary edema, with severe mitral regurgitation with flail leaflet.
- interventricular septum rupture/defect –> within 3-5 days –> new holosystolic murmur –> stepped up O2 level between right atrium and ventricle.
- Free wall rupture –> within 5-14 days –> pericardial tamponade, jugular venous distention and distended heart sound
Psychologic vs organic causes of impotence
Psychological is abrupt with rapid onset while organic is intermittent and later became more persistent . Also the absence of morning erection in patients with organic problems
Papillary muscles and inteventricular septum blood supply
Papillary muscles: -Anterolateral 2/3 LAD -posteromedial 1/3 PDA Interventricular septum: -anterior 2/3 by LAD -posterior 1/3 by PDA
Burkett lymphoma histology
The histology for burkitt lymphoma is diffuse, medium sized lymphocytes and high proliferation index represented by high Ki-67 fraction (approaching 100%). Classic starry sky is seen.
Amniotic fluid embolism VS DIC after placental abruption
Amniotic fluid embolism is associated with hypotension and cardiogenic shock while placntal abruption present with hypertension,
Malaria treatment
Mefloquine ,quinine analogue.
Chloroquine
Atovaqione-proguanil and artemisinis
aldesleukin
IL-2 analogue , is used for metastatic melanoma and RCC. This is due to increased levels of NK cells.
Corticosteroids effect on COX
Reduce COX-2 expression and decrease synthesis of arachidonic acid via phospholipase A2 inhibition.
Choclate colored blood
Methemoglobinemia (brown)
Normal A-a gradient value
Between 5-15 mm Hg.
Hypoxemia in the setting of normal A-a gradient indicates that both alveolar and arterial partial pressure of oxygen are low.
methotrexate mechanism
- After entering the cell it undergoes plyglutamation –> prevents movment of MTX out of the cell -> intracellular accumulation for later use.
- folate and recycled DHF are stored within the cell via polyglutamation.
Malaria diagnosis
Examination of peripheral blood smear with giemsa staining. In p.falciparum infection, RBC have multiple rings called trophozites
Pulsus paradoxus
Abnormal exaggerated decrease in systolic BP > 10 mm Hg decrease on inspiration.
Malabsorption
May occur with diarrhea and steatorrhea( bulky, foul smelling, visible oil droplets, greasy toilet rings) most patients have non specific symptoms such as weight loss, fatigue or vague abdominal discomfot. Also patients may have nutrient deficiencies.
Terbinafine mechanism of action
Inhibition of squalene epoxidase. Used for dermatophytes
PKU is deficiency in
Phenylalanine hydroxylase. Pts can convert phenylalanine –> tyrosine
Failure of extraembryonic gut to return to the abdominal cavity following herniation and rotation
Omphalocele or gastrochisis
Sudan III stain
Fats are typically the earliest and most severely affected nutrients in generalized malabsorption, and testing for fat malabsorption is therefore the most sensitive strategy for screening for malabsorptive syndrome.
- a qualitative assay of stool with Sudan III stain can quickly and easily identify unabsorbed fat and confirm malabsorption.
(Stools should normally have no measurable fat)
Phenylketonuria
Autosomal recessive disease, caused by mutation that codes for phenylalanine hydroxylase.
- phenylalanine levels are measured in all neonates for screening in US.
- signs: intellectual disability, gait or posture abnormality, eczema , and musty body odor.
The best way to decrease MR with left sided heart failure is to decrease
Left ventricular after load
Etiologies of hypoxemia
- Normal A-a gradient:
- hypoventilation: obesity hypoventilation syndrome, neuromuscular disorder
- low inspired fraction of O2: high altitude - Elevated A-a gradient:
- right to left shunt: cardiac septal defects, pulmonary edema
- V/Q mismatch: PE, COPD
- impaired diffusion: interstitial lung disease
P.jirovecii treatment
Pentamidine, can also treat leshminiasis and african sleeping sickness.
Azygos vein loclization
It lies in the posterior mediastinum immediately right of the midline. It drains blood from the posterior intercostal veins into the superior vena-cava
Ivermectin used to treat
River blindness, onchocerciasis
IL-2
Produced by TH. Antigen binding to the TCR stimulates the secretion of IL-2 and expression of IL-2 receptors.
- it then stimulates the growth, differentiation and survival of antigen specific CD4+ T cells and CD8+ t cells.
- it also promote growth of B cell and activates NK cells.
Staphylococus promote the growth of hemophilus infleuenzae type b
Hemophilus infleunzae requires both factor X (hematin) and factor V(NAD+) to support growth.
-growth of H.infleuenzae on sheep blood agar can be achieved by cross streaking the medium with s.aureus colonies because it actively secretes V factor (NAD+) into medium . This is known as satalite phenomenon.
Malabsorption causes
- Pancreatic: pancreatitis chronic, CF
- Mucosal disorders: celiac, IBD,
- Bacterial overgrowth: GI surgery, abnormal motility or parasitic diseases(giardia)
Emphysema spirometry changes (COPD)
- increase in RV and TLC
- Decrease in FEV1/FVC and in FVC
Chagas disease
Nifrutimox
Medial medullary syndrome
Infarction of ASA, pts typically presents with contralateral hemiparesis(corticospinal tract) , contralateral hemisensory loss(medial leminscal pathway) and ipsilateral tongue paralysis(hypoglossal nerve)
