Block 45 Flashcards
Western blotting
Is used to detect a target polypeptide or protein from within a mixed sample. Potential target proteins are seperated by gel Electrophoresis.
Cerbellar ataxia, telangectasia and increased risk of infection
Ataxia telengectasia syndrome
Autosomal recessive condition due to mutation in ATM gene which is responsible for DNA break repair.
-telengectasia : supreficial blanching nests of distended capillaries
- ataxia
-IgA deficiency
-increased AFP, decreased IgG, IgA, and IgE.
-cerbellar atrophy
Matrix metalloprotinease (MMP)function in wound
Its secreted by various cell types such as macrophages, neutrophils, synovial cells, some epithelial cells.
- it primarily function in the degradation of collagen and other proteins in extracellular matrix.
- MMP activity is important in wound healing, as it encourages both myofibroblast accumulation at the wound accumulation at the wound edges and scar tissue remodeling.
- the amassed myofibroblasts initiate wound contraction during healing by second intention.
- contracture may occur when unusually pronounced MMP activity results in excessive wound contraction.
Diagnosis of GCA (temporal)
- elevated ESR and CRP
- temporal artery biopsy shows intimal thickening, elastic lamina fragmentation and multi-nucleated giant cells.
- angiography isnt as sensetive as ESR and CRP for initial assesment.
Pure red cell aplasia(PRCA)
Rare form of marrow failure charactrized by severe hypoplasia of marrow erythroid elements in the setting of normal granulopoiesis and thrombopoiesis.(normal WBC and platelets).
- the pathogenesis of PRCA often involves the inhibition of erythropoietic precursors and progenitors by IgG autoantibodies or cytotoxic T lymphocytes.
- it has been associated with immune system disease such as thymomas and lymphocytic leukemias.if thymoma is present, removal of thymus can resolve the problem
- it can also arise from B19 infection, the virus pereferntially attacks and destroys pro-erythroblasts. Recent parvovirus infection can be confirmed via the detection of anti-B19 IgM antibodies.
- patients presents with low reticulocytes count, normocytic anemia
Cysteine tellurite agar
Bordett gengou medium
Cysteine tellurite = cornybacterium diphteriae- dark black .
also can be cultured on lofflers medium where it develop cytoplasmic metachromatic granules.
Bordett gengou medium = bortadella pertusis
Aging changes in spirometry
- Patients age >35 experience steady decrease in chest wall compliance as a result of stiffening from Rib calcification and from increased thoracic curvature due to osteoporosis and osteoarthritis.
- diminished elastic recoil and the collapse of supporting tissues around the airway causes a significant increase in RV. However TLC remains unchanged because the decreased chest wall compliance counterbalance increasing in lung compliance.
Restless leg syndrome
Clinical features:
-uncomfortable urge to move the legs with unpleasant sensation in the legs, onset with inactivity or at night, relief with movement (walking stretching ).
-causes:
Idiopathic, iron deficiency, uremia, diabetes
Treatment:
-avoidance of aggravating factors (alcohol, sleep deprivation)
-dopamine agonists (pramipexole).
Aspiration pneumonia develops
- develops in the most dependent portions of the lung.
- patients who aspirate while lying supine typically have involvement of the posterior segments of the upper lobes and the superior segments of the lower lobes.
- in addition the right main bronchus is more prone to aspiration that the left main bronchus and has a larger diameter, is shorter, and is more vertically oriented than the left main bronchus.
Dengue fever symptoms
2 types, classic and hemorrhagic fever
- Classic: flu like febrile illness with marked mylagia, and joint pains. Retro-orbital pain, rash.
- Dengue hemorrhagic fever: increased vascular permeability, thrombocytopenia, spontaneous bleeding —> shock, positive tourniquet test (petechiae after sphygmomanometer cuff inflation for 5 minutes)
Dengue fever features
Dengue viruses are transmitted by the aedes mosquito and are single stranded RNA viruses with 4 different serotypes (DENV1-4).
Corticosteroids changes on immune system
- Neutrophilia due to neutrophils demargination.
- Immunosupression
- Increase risk of infection
Pyruvate dehydrogenase deficiency
Inherited inborn error of metabolism often presenting in infancy with lactic acidosis and neurologic defects.
- the disease results from deficient activity of the pyruvate dehydrogenase complex, the lack of this enzyme leads to buildup of pyruvate which is shunted to lactate via lactate dehydrogenase generating lactic acidosis.
- disease managment involves the implementation of a ketogenic diet, high fat, and low carbohydate food with low levels of proteins.
- the diet forces the production of ketone bodies from fat and amino acid to fuel up the body in place of glucose.
- ketogenic amino acid metabolism generates the ketone body precursor actyl-CoA.
- lysine and leucine are exclusively ketogenic amino acids, they cant be metabolized to pyruvate and consumption will not lead to increased production of lactic acid.
Radical mastectomy, after few years violaceous nodules appear on arm
- chronic lymphedema is a risk factor for development of cutaneous angiosarcoma. This is usually post mastectomy with axilalry lymph nodes dissection complication.
- histologically, it shows infiltration of the dermis with slit like abnormal vascular spaces.
- prognosis for patients with angiosarcoma is poor because tumor is usually widespread by the time of diagnosis.
Dopamine features
Its an adrenergic agonist that have varying effects based on the dose. At lower doses, it stimulates D1 receptors in the renal vasculature and tubules, inducing increase in renal blood flow, glomelular filtration rate and sodium excretion.
- as the dosage increase, dopamine begins to stimulate ß1 adrenergic receptors in the heart increasing cardiac contractility, HR, and systolic BP.
- at the higher end of dose range (increase further more) stimulation of å1 receptors in systemic vasculature leads to generalized vasoconstriciton along with decrease cardiac output due to increase afterload.
Tuberous sclerosis
Autosomal dominant condition charactrized by cortical tubers and subependymal hamartomas in the brain.
- renal angiomyolipoma is a benign tumor, they are highly associated with this disease.
- cardiac rhabdomyomas, facial angiofibromas, and leaf shaped patches of skin lacking pigment can also occur (ash leaf patches)
ATN phases
3 phases
- Intitation phase corresponds with the original ischemic or toxic insult and last about 36 hours.
- Maintenance phase : tubular damage is fully established and patients commonly have oliguria, fluid overload and electrolyte abnormalities.it lasts 1-2 weeks until GFR stabilizes.
- Recovery phase: its charactrized by “re-epithelization” of the tubules. The GFR recovers relatively quickly as the tubules clear of casts and debris. However the tubular cells recover more gradually resulting in transient polyuria and loss of electrolytes due to impaired tubular resorption and decreased renal concentrating ability.
Neutric plaques
Another name for senile plaque found in Alzheimer diseae.
Acute intermittent porphyria treatment
The mainstay is to inhibit the whole heme synthesis process. Glucose or hemin inhibits ALA synthase and are used in AIP managment.
Measles virus clinical and complication
Clinical presentation:
-prodrome with cough, coryza, conjucivitis, fever, koplik spots.
-macupapular exanthem which spares the palms and soles and cephalocaudal spread.
Complication:
1. Primary measles pneumonia
2. Secondary bacterial infections (pneumonia or otitis media)
3. Neurologic (encephalitis, acute disseminated encephalomyelitis, subacute sclerosing panencephalitis ).
High frequency deep brain stimulation targeted to treat parkinson disease
- Nigrostriatal degeneration in Parkinson disease results in excessive excitation of the globus pallidus internus by the subthalamic nucleus which in turn cause excessive inhibition of the thalamus.
- reduced actiivity of the thalamus and its projection to the cortex consequently result in rigidity and bradykinesia.
- patients with medically intractable symptoms of parkinson disease may benefit from high frequency deep brain stimulation of the globus pallidus internus or subthalamic nucleus.
- high frequency stimulation inhibits firing of these nuclei. This causes increased activity in the downstream nuclei, resulting in thalamocortical disinhibition with improved mobility.
Alcohol related chronic pancreatitis
- its thought that alcohol related chronic pancreatitis develops in part due to alcohol induced secretion of protein rich fluid.
- these proteinaceous secretion can precipitate within the pancreatic ducts forming ductal plugs that may calcify and be detectable on abdominal imaging.
- ductal obstruction by such concretions may cause exocrine insufficiency due to atrophy of the pancreatic acinar cells and pancreatic fibrosis.
- pancreatic exocrine insufficiency leads to malabsorption with consequent diarrhea/steatorrhea.
- weight loss and bulky, frothy stools are typical clinical findings. This patients abdominal pain is most likely due to the pancreatitis itself.
Hives treatment
Hives are triggered in most cases by IgE dependent mast cell degranulation.
- as histamines is one of the primary mediators in this type of allergic reaction, antihistamines are the preferred treatment in most cases.
- loratidine and cetirizine are helpful
Pupil that dont react to light but do constrict with accomodation
Arhyll robertson pupils
Tabes dorsalis
What histological finding confirm irrevesible damage in the myocardium
-the appearance of vaculoes and phospholipid containing amorphous densities within mitochondria generally signifies irreversible injury, and implies a permanent inability to generate further ATP via oxidative phosphorylation. When the mitochondria are injured irreversibly the cell cannot recover. However simple mitochondrial injury can be associated with reversible damage.
Congeital hydrocephalus
Its caused by aqueductal stenosis and chiari malformation.
Symptoms include macrocephaly, bulging fontanelle, poor feeding, developmental delay, spasticity and hyperreflexia.
Mucle hypertonicity as well may arise (UMN symptoms)
Treatment include cerberal shunt
I-cell disease
AR disorder, lysosomal storage disease.
- it occurs due to defects in protein targeting, a process by which proteins are transported to their appropriate intra of extracellular location.
- post translational modification such as glycosylation and phosphorylation often function as markers that help guide the protein to its final destination.
- defective phosphotransferase enzyme causes extracelluar secretion of the proteins targeted for lysosomes, and accumulation of cellular debris in the lysosomes, forming characteristic inclusion bodies seen in I-cell disease.
- patient present with this disorder typically present with failure to thrive and cognitive deficits in the first year of life along with characteristic physical features (eg, coarse facial feature, corneal clouding).
Proteins targeted for lysosomes
Modified differently than those destined for extracellular secretion. A golgi body phosphotransferase enzyme catalyzes the phosphorylation of mannose residues on lysosome bound proteins, allowing them to traverse the golgi network and ultimately be transported to the lysosomes where they serve as catalysts for degredation of cellular components.
Cystitis pathophysiology in women
Pyleonephritis development
In women, sexual intercourse facilitates bacterial ascent by relatively short urethra and into the bladder which have several antibacterial defenses such as bladder mucosa that doesn’t allow bacterial attachment, urine flow , and normal urine is bactericidial with high urea content and osmolarity.
- when these mechanisms are disrupted or overcome due to bacterial virulence factors , cystitis occurs.
- frequent cystitis occurrence can weaken the veriscureteral valve leading to vesicuretral reflux —> pyelnophritis
High altitude changes
- hypobaric hypoxia —> low Po2
- hyperventilation in an attempt to improve oxygenation —> hypocapnia —> respiratory alkalosis.
- renal bicarbonate excretion compensate for alkalosis stabilizing the normal PH range within 48 hours.
Measles lead to what complication in the brain
Subacute sclerosing panecnephalitis
Pterion fracture
Fracture at the pterion (region where frontal, parietal temporal and sphenoid meet in the skull )
- the bone is thin and fracture there raise the risk for lacerating the middle meningeal artery and causing epidural hematoma.
- the middle meningeal artery is a branch of maxillary artery, which enters the skull at the foramen spinosum and supplies the dura mater and periosteum
Charcoal yeast extract medium
Supplemented with L-cysteine and iron (factor V,X) used for legionella pneumonia.
-its commonly contaminate natural bodies of water, municipal water supplies and water based cooling system found in commercial and hospital settings. Its frequent nosocomial sources of infection.
Identifying spinal cord level by picture
Moving rostally the amount of white matter steadily increase and section becomes more ovoid (particulary in upper thoracic and cervical regions).
Also the ventral horns of the lower cervical and lumbosacral regions are more prominent as these areas innervate the muscles of the arm and legs respectively.
Cavernous hemangioma complication
- they most commonly occur within the brain parynchema above cerbellar tentorium.
- patients often have seizures and may develop profressive neurologic deficits due to mass effect with interruption of cerberal microcirculation.
- these lesion have the tendency to bleed which can lead to intacerebellar hemorrhage.
S4
Its a sign of diastolic dysfunction, it occurs due to a sudden rise in EDV pressure caused by atrial contraction that has reached its elastic limit. It can be present in any condition that decrease ventricular compliance.
What is the fastest way to reverse warfarin effect
FFP which contain all of the coagulation factors unlike cryoprecipitates which contain only soluble proteins like factor VII , VwF and vitronectin.
Pulmonary hypertension due to LV HF
It begins with passive increase in capillary and arterial pulmonary secondary to pulmonary venous congestion.
-the high pressure —> endothelial damage -> capillary leakage of serum proteins into intestitium —> decreased production of NO and increased production of endothillin ->increased vascular tone —> over time remodeling occur with increased smooth muscle cell proliferation.
Antipsychotic side effects
- Extrapyramidal side effects:
- acute dystonic reaction : sudden onset sustained muscle contractions.
- akathisia: subjective restlessness with inability to sit still (can be treated with beta blockers or carbamazepine)
- drug induced parkinsonism: tremor, rigidity, bradykinesia, masked facies. - Tardive dyskinesia: involuntary movements after chronic use such as lip smacking and choreoathetoid movements.
- Neuroleptic malignant syndrome
Nitroprusside infusion can lead to what toxicity
Cyanide toxicity.
- cyanide is a potent mitochondrial toxin that binds to Fe3+ in cytochrome C oxidase, inhibiting ETC and halting aerobic respiration in the cell.
- its normally metabolized in the tissues by rhodanese, an enzyme that transfers a sulfur molecule to cyanide to form thiocyanate which is less toxic and excreted in the urine.
- cyanide overdose depletes the available sulfur donors, allowing cyanide to accumulate in toxic amounts.
- sodium thiosulfate works as antidote by providing additional sulfur groups for rhodanese, enhancing cyanide detoxification, its used in conjunction with hydroxocobolamin and sodium nitrite in management of cyanide toxicity.
Clinical manifestation of hemochromatosis include
- hepatomegaly (bronze diabetes )
- diabetes mellitus
- skin hyper-pigmentation (particularly in sun exposed areas)
myobacterium avium complex (MAC)infection
- MAC occurs in HIV patients with CD 4+ counts <50 cells/uL
- MAC typically present with the nonspecific symptoms of fever, weight loss , and diarrhea in an HIV + patients.
- MAC grows well at high temperatures and will exhibit optimum growth 41 C.
- MAC is resistant to many of the typical antimycobacterial drugs. As such, disseminated infection is treated with clarithromycin or azithromycin in combination with rifabutin or ethambutol.
- MAC can be prevented with weekly azithromycin at high risk HIV + pts.
BRAF mutation is present in
Melanoma.
- its a protein kinase involved in activating the signaling pathways of melanocyte proliferation. BRAF mutation V600E (valine -> glutamic acid) seen in 40-60% of patients with melanoma, leads to greatly increased activation of signaling pathway for melanocytes growth, survival and metastasis.
- vemurfaenib, a potent inhibitor of mutated BRAF has significant anti tumor effect with improved survival and long term outcomes in advanced stage V600E patients.
Cardiac changes with normal aging.
- decreased LV chamber size, particularly in apex to base dimension. This decrease in chamber length causes sigmoid shape septum acquiring.
- atrophy of the myocardium results in increased interstitial connective tissue, often with concomitant extracellular amyloid deposition.
- within cardiomyocytes, there is progressive accumulation of cytoplasmic granules containing brownish lipofuscin pigment (the result of indigestible byproducts of sub-cellular membrane lipid oxidation).
Eosinophils against parasitic infection
Eosinophils proliferation and activation during parasitic infection is stiumulated by IL-5 produced by TH2 and mast cells.
- when parasite invades the mucosa or enters the blood-stream, its coated by IgG and IgE antibodies that bind the Fc receptors located on the eosinophil cell surface.
- this triggers eosinophils degranulation and release of cytotoxic proteins (major basic protein) and reactive O2 intermediates, substances that damage and destroy antibody bound parasites. The mechanism is an example of antibody dependent cell mediated cytotoxicity (ADCC) which is also used by macrophages, neutrophils, and NK cells.
Permissiveness
It occurs when one hormone allows another to exert its maximal effect.
Example of that include cortisol which excerts its potentiating effect in part through upregulation of alpha- adrenergic receptors on vascular smooth muscle cells. In adrenal insufficiency, low glucorticosteroids levels can contivute to hypotensive crisis by decreasing vascular responsiveness to AG II and NE.
Causes of RPGN
- Anti GBM (goodpasture syndrome)
- Immune complex RPGN
- Pauci immune RPGN
Vitamin A toxicity
Acute : nausea, vomiting, vertigo, and blurred vision
Chronic: alopecia, dry skin, hyperlipidemia, hepatotoxicity, hepatosplenomegaly and visual difficulties, pseudotumor cerebri can result also and can lead to papilledema.
Follicular lymphoma
- is the most common indolent NHL in adults and second most common overall.
- it have long, waxing and waning clinical course.
- this condition most often presents in middle aged patients with painless lymph node enlargement(fluctuating lymphadenopathy) or abdominal discomfort from an abdominal mass.
- histology is notable for mixture of cleaved and noncleaved follicle center cells in nodular pattern.
- t(14,18) is present. (Overexpression of BCL-2)
Cachexia
Syndrome that encompasses anorexia, malaise, anemia, weight loss and generalized wasting due to underlying systemic disease.
- its a manifestation of neoplasm.
- TNF-å is a cytokine that causes necrosis of some tumors in vitro and produces symptoms of cachexia. Its produced by macrophages.
- its role in cachexia is explained by its influence on the hypothalamus, leading to appetite suppression. Its also increases basal metabolic rate.
Turner syndrome on ovaries
Have variable degree of ovarian dysgenesis. The ovaries usually appear underdeveloped and atrophic “streak gonads”.
Common Clinical disinfectants
- alcohols (isopropanol, ethanol) —> disrupts cell membranes, denaturing of proteins.
- Chlorhexidine -> disruption of cell membranes and coagulation of cytoplasm
- Hydrogen peroxide —> produces destructive free radicals that oxidize cellular components
- Iodine -> halogenation of proteins and nucleic acid.
Radioimmunoassay
Its a laboratory technique that uses specific antibodies and a known quantity of radiolabled antigen to determine the amount of antigen present in unknown sample.
- in this technique, specific antibodies against a known antigen are attached to an assay plate. Next, a fixed quantity or radiolabeled antigen and varying quantities of unlabled antigen are added to the plate.
- the system is subsequently washed to remove unbound antigens and radioactivity is measured.
Abusive head trauma (previously, shaken baby syndrome)
its inflicted intracranial injury due to blunt force trauma or vigorous shaking in a to and fro fashion.
- the injury are due to infants unique anatomic features. Infants have large heads, enlarged subarachinoid spaces, higher brain water content and decreased cervical muscle tone compared to older children.
- these factors lead to increased movement of the immature brain in relation to the skull, resulting in tearing of the bridging veins and subdural hemorrhages.
- the shaking motion also results in retinal hemorrhages due to rupture of congested retinal veins. Retinal hemorrhage are highly suggestive of AHT.
Failure of ovulation treatment
failure of ovulation is a common cause of infertility . Treatment options include the administration of drugs that act like FSH and LH. Menotropin therapy mimics FSH and triggers the formation of dominant ovarian follicle. When the follicle appears mature exogenous hCG is administered. The alpha subunit of hCG is structurally similar to LH and therefore stimulate the LH surge by inducing ovulation.
Cytoplasm of typical cell and membrane potential
the cytoplasm f typical cell is charactrized by low concentration of Na and high concentration of K. The extracellular fluid is inversely rich in Na and low in K.
- this difference in Na and K concentration is maintained by the Na/K ATPase which pumps three ions out of the cell for every 2 K ions allowed into the cell.
- outflow of K ions through non gated channels maintains the negative charge inside the membrane which approaches the equilibrium potential for K. There are however a small number of channels that allow the flow of Na into the cell.
- this small influx of Na ions decreases the membrane potential and for this reason the resting potential of the membrane is always less negative than the equilibrium potential for K
HCV virus, genetic instability is caused by
HCV virus has >6 genotypes and multiple subgenotypes. These variants strains differ primarily at hypervariable genomic regions such as those found in the. Sequences encoding its 2 envelope glycoproteins.
-moreover there is no proofreading 3’ -> 5’ exonuclease activity built into the virion encoded RNA polymerase. As a result, the RNA polymerase makes many errors during replication and several dozens subspecies of HCV are typically present in the blood of an infected individual at any one time.
Meningococcus virulent factors and available vaccine
its common in college students living in dormitory and clinically may present as acute onset symptoms, with pruritic rash and myalgia.
- virulent factors include antiphagocytic polysaccharide capsule, lipooligosaccharide, pilli, and IgA protease.
- vaccine available include polysaccharide capsule and conjugate vaccines. The polysaccharide quadrivalent vaccine is made from the outer polysaccharide capsule, the conjugate vaccine are mode from capsular polysaccharide antigens individually conjugated to diphtheria toxoid protein.
Histopathological manifestaion of chronic HBV infection
accumulation of hepatitis B surface antigen within infected hepatocytes.
- this results in the appearance of finely granular, diffusely homogenous, pale eosinophilic cytoplasm (“ ground-glass” hepatocytes )
- other nonspecific morphological changes include hepatocyte necrosis (balloning degeneration, apoptosis, steatosis, and portal inflammation with mononuclear inclusion).
HCV infection morpho-histo pathological
HCV commonly have lymphoid aggregates within the portal tracts and focal areas of macrovesicular steatosis.
Sudden upward jerking injury
can cause injury to the lower trunk of the brachial plexus. The lower trunk carries nerve fibers from the C8-T1 spinal levels that ultimately contribute to median and ulnar nerves. Together these nerves innervate all of the intrinsic muscles of the hand.
- injury to the lower trunk of the brachial plexus may cause paralysis of all the intrinsic hand muscles (klympke’s palsy).
- weakness of lumbircals causes impaired flexion of MCP joints and impaired extension of IP joints.
- relative sparing of the extrinsic flexors and extensors of the hand contribute to the total claw hand deformity seen in this condition.
- senseory loss can also occur over the medial aspect of the hand/ forearm.
- involvement of T1 can cause horners syndrome
Tumor stage vs grade
The extent of tumor expansion is charactrized by stage of a tumor. The degree of tumor differentiation is referred to as grade. Tumor stage is the most important criteria for determining prognosis.
- if the tumor is confined to the mucosa, the patinet has 90%+ chance of 5-year survival
- if its involve the muscular later, 5 year survival is at 70-80%.
- lymph node involvement and distant metastasis have poor prognosis.
- stage is more important than grade in determining the prognosis of colon cancer.
Why the lung is unlikely to undergo infarction
Because of the presence of dual blood supply which are pulmonary and bronchial arteries
Ilihypogastric nerve
Arises from the L1 nerve root, emerges from the lateral border of the upper psaos major, and passes behind the kidney anterior to the quadratus lumborum.
- the nerve provides motor function to the anterolateral abdominal wall muscles.
- its anterior branch emerges above the superficial inguinal ring innervates the skin above the pubic region. The lateral branch descends over the iliac crest to innervate the gluteal region.
- injury to the anterior branch during appendectomy causes decreased sensation at the suprapubic region.
Ziduvudine
NRTI used to treat HIV. It competitively binds to reverse transcriptase and is incroporated into the viral genome as a thymidine analog. However, it has an azido group in place of hydroxyl group normally found on the 3’ end of thymidine.
- because a free 3’ hydroxyl group is required for new nucleotides to be added to replicating DNA, the azido group on zidovudine prevents DNA chain elongation.
- it inhibits 3’ —> 5’ phosphodiaster bond formation
Internal Hemorrhoids
Chronically increased venous pressure due to prolonged straining or breakdown of supporting tissue due to advancing age can cause the cushions to bulge into the anal canal where they can become inflamed, thrombose or prolapse.
- hemmorhoids can be treated with rubber band ligation, which cuts off the blood supply to the lesions and cause them to degenerate.
- internal hemorrhoids drains into the inferior messenteric vein while the external hemorrhoids drains into the internal pudendal vein.
Bloom syndrome
Rare AR disorder caused by mutation in BLM gene, which is responsible for helicase coding.
-helicase dysfunction result in chromosomal instability and breakage and manifests clinically with growth retardation, facial anomalies, photosensitive rash and immunodeficiency.
Primaquine and chloroquine treatment
Chloroquine is effective in eradicating chloroquine sensetive plasmodia from the blood stream, but it has no activity against latent hepatic infections established by P vivax and P ovale.
-primaquine must be added to completely eradicate the hypnozoites
Porcelain gallbladder
- firm palpable gallbladder, with extensive calcification throughout the gallbladder wall.
- RUQ pain
- pts may be assymptomatic and finding incidentally on CT scan.
- its a potential manifestation of chronic cholecystitis and is often found in association with multiple gallstones.
- patients have increased risk for developing gallbladder carcinoma.
Primary spontaneous pneumothorax
It occurs when a large change in the alveolar or intrapleural pressure results in a break in the visceral pleura and subsequent trapping of air between the parietal and visceral spaces.
-the superficial alveoli in the apices expirience greater pressure changes predisposing them to formation of subpleural blebs. The blebs can spontaneously rupture through the visceral pleura, frequently while the patient is at rest.
Allupurinol effect on acute gout
Prophylactic therapy such as allupurinol shouldnt be given in acute gout as acute changes in serum uric acid levels can worsen acute attacks rather should be given between attacks.
Tetnus toxin effect
Toxin first binds to receptor in the presynaptic membanes of peripheral motor neurons. From there it migrates by retrograde axonal transport to central inhibitory neurons in spinal cord and brainstem —> inhibit secretion of Glycine and GABA —> increased activation of motor neurons.
Systemic sclerosis pulmonary complication
Pulmonary hypertension is common complication, collagen deposition in pulmonary arterioles and capillaries in response inflammatory response tiggered by accumulation of monoclonal T cells in affected tissue—> microvascular injury of pulmonary arterioles leads to narrowing of the lumen and increased pressure in pulmonary circulation. It leads to hypertrophy of the right ventricle, with subsequent development of right CHF.
Hashimoto thyroditis
It occurs predominantly in women, with a peak incidence at age 45-65 and is the most common cause of hypothyroidism in iodine sufficient regions such as USA.
- as with all forms of primary hypothyrodism, laboratory studies show low serum T4 levels and elevated TSH.
- elevated antithyroid peroxidase antibody can confirm the diagnosis. If the diagnosis is initially uncertain, a biopsy can be done to rule out malignancy.
- biopsy results will show intense mononuclear infiltrate consisting of lymphocytes and plasma cells, often with germinal centers. Residual follicles are often surrounded by hurthle cells, which represent follicular epithelial cells that have undergone metaplastic change in response to inflammation.
Reid index
The major contributer to the all thickening is the submucosal mucous gland enlargment, which can quantified by the ratio of the thickness of the mucous gland layer to the thickness of the wall between epithelium and cartilage (reid index).
-its normally = 0.4.
Cherry hemangioma
Small, bright red, papular lesion also known as cherry hemangioma or senile hemangioma.
- most common benign vascular tumors in adults and typically appear during the third or fourth decade of life.
- the lesions do not regress spontaneously and often multiply with age.
Cerbellar hemisphere vs cerbellar vermis injury
Cerebellar hemisphere injury is associated with limb dysmetria which is overshoot or undershoot during targeted movement, its usually due to involvement of the lateral descending motor systems .hemispheric cerebellar lesions may also cause tremor during goal directed activity (intention tremor).
- cerebellar vermis features include cerebellar hemorrhage which includes nausea and occipital headache. The cerebellar vermis modulates axial/truncal posture and coordination via connections with the media descending motor system. Consequently, acute lesions to this region typically result in truncal ataxia, charactrized by a wide-based, unsteady gait.
- patients may also develop vertigo and nystagmus due to involvement of the inferior vermis and flocunodular lobe (which modulates balance and ocular movements via connection with the vestibular nuclei and MLF.
Prolonged history of episodic abdominal discomfort, faltulence and voluminous greasy stools along with pruritic rash over elbows and knees
It suggests dermatitis herpetiformis(DH) due to celiac disease ( increased intestinal intraepithelial lymphocytes).
- DH is characterized by erythematous pruritic papule, vesicles, and bullae that appear bilaterally and symmetrically on the extensor surfaces, upper back and buttocks.
- its charactrized histologically by micro-abscesses containing fibrin and neutrophils at the dermal papillae tips.
RA —> pulmonary fibrosis
RA can cause variety of pulmonary diseases the most common being form of interstitial lung disease similar to idiopathic interstitial pneumonia.
-also methotrexate which is commonly used in RA, can lead to interstitial pneumonitis and fibrosis.
Bacterial vaginosis treatment
Clindamycin or metronidazole are effective treatment against BV, clindamycin is bacteriostatic drug that inhibit protein translation by binding to the 50S ribosomal subunit, while metronidazole is bactericidal and damages the DNA of facultative anaerobes.
Diverticulosis
It most commonly affects the sigmoid colon, usually seen in 60< patients. Most patients are asymptomatic but some may present with hematochezia due to disruption of blood vessels nearby.
-the pathogenesis of diverticulosis involves pulsion or increased intraluminal pressure created during strained bowel movements (due to chronic constipation).
Increased pressure causes the mucosa and submucosa to herniate through areas of focal weakness in the muscularis (false diverticula).
Acute serum sickness
Condition caused by tissue deposition of circulating immune complexes. The most common manifestation include fever, pruritic skin rash, and arthalgias that begins 7-14 days after exposure to an antigen.
Lymphadenopathy and proteinuria may also occur in some patients. Histologic examination of affected tissues typically shows small vessel vasculitis with fibrinoid necrosis and intense neutrophil infiltration.
-deposition of of IgG and/or IgM complement fixing antibodies results in localized complement consumption and hypocomplementemia.
-serum sickness can occur following administration of antigenic heterologous proteins such as chimeric monoclonal antibodies or nonhuman immunoglobulin.
Alcohol related pancreatitis
Is clinically indistinguishable from acute pancreatitis, however the systemic effect of ethanol can be distinguished such as liver injury, macrocytosis is often seen and so on.
-AST:ALT ration is >2 and absence of gallstones.
Hyperaldosteronism aldosterone escape
Is characterized by increased Na+ reabsorption from the collecting tubule. This creates a negative charge in the lumen, pulling K+ and H+ from tubular cells and leading to increased exretion of urinary K+ and H+. As a result, hypokalemia is common.
- increased H+ excretion by a-intercalated cells promotes bicarbonate production and increased activity of the basolateral HCO3/Cl- exchanger, resulting in metabolic alkalosis.
- despite the increase in sodium absorption, hypernatremia and pedal edema are rarely observed due to aldosterone escape.
- the increased intravascular volume causes increased RBF with resulting pressure natriuresis and augmented release of ANP. This limit net sodium retention and prevents development of overt volume overload and significant hypernatremia.
Beta thalassemia defect
Beta thalasemia affects beta chain production and can be caused by a variety of DNA mutation affecting the transcription, processing and translation of beta globin mRNA.
-most commonly these mutations causes aberrant recursor mRNA splicing or premature chain termination during mRNA translation. In some cases point mutation prevent RNA polymerase from binding to promoter region the resulting ßdeficiency occur in the serting of normal heme and alpha chain synthesis, leading to increased production of hemoglobin A2 and hemoglobin F.
Placenta accreta
Refers to a placenta that is morbidly adherent to the myometrium. Scar tissue from prior surgery can result in a malformed or absent decidual layer between the placenta and the myometrium, allowing direct myometrial attachment by the villous tissue and preventing normal placental seperation after fetal delivery.
-placental accreta is usually diagnosed durring prenatal care and managed by C-section followed by hysterectomy.
How is uterine atony postpartum bleeding stops
Uterotonic agents.
-if placenta removed in pieces it suggests placenta accreta as the cause of postpartum hemorrhage rather than uterine atony
RBF
RBF = (renal artery pressure- renal vein pressure)/ renal vascular resistance.
This is invasive and difficult to achieve , easier way is
RBF = (RPF)/1-hematocrit
RPF calculated using PAH clearance = (urine PAH X urine flow rate / plasma PAH )
Scotoma
The term scotoma refers to any visual defect surrounded by by a relatively unimpaired field of vision. Scotomas occur due to pathologic processes that involve parts of the retina or optic nerve. Examples include demyelinating disease such as MS, diabetic retinopathy and retinitis pigmentosa.
-macular degeneration which is age related, is charactrized by progressive loss of central vision due to deposition of fatty tissues (drusen) behind the retina. This results in central scotoma.
Kegel exercises and prolonged labor
Women who are obese or have prolonged second stage of labor, multiple vaginal deliveries, or previous pelvic surgery are at increased risk for pelvic floor injury.
- the pelvic floor is composed of the levator ani muscles ( iliococcygeus, pubococcygeus,pubreticalis) hold the bladder and the urethra in the appropriate anatomic position. Injury to these muscles results in urethral hyper-mobility( and/or pelvic organ prolapse such as cytocele.
- first line of management of stress urinary incontinence is through lifestyle modifications such as increased dietary fiber preventing straining. Urethral can be strengthened through pelvic floor exercises such as kegel exercises involving squeezing and releasing the levator ani muscles a few times each day.
Pneumatosis intestinalis
It can be seen on abdominal X-ray as thin curvilinear areas of lucency that parallel the lumen.in an infant with abdominal distention and bloody stools, this finding is diagnostic for necrotizing enterocolitis(NEC).
- NEC is one of the most frequent GI emergencies affecting newborns. It occurs predominantly in preterm infants secondary to GI and immunologic immaturity. Upon initiation of enteral feeding, bacteria are introduced into the bowel where they proliferate excessively due to compromised immune clearance. Impaired mucosal barrier function allow bacteria to invade bowel wall, causing inflammation and ischemic necrosis of the terminal ileum and colon.
- up to 30% of infants die especially if intestinal perforation is present.
HSV II (genital) symptoms
Systemic symptoms such as fever, myalgia, inguinal lymphadenopathy and itchy, painful, vesicular genital rash.
-genital herpes is most commonly caused by HSV 2.
-the characterestic rash on the genitalia or buttocks occurs in stage, vesicles, ulcers and then crusting.
-following infection, HSV lies dormant in the sacral dorsal root ganglia and can be reactivated to cause recurrent genital lesions. Recurrence tend to be localized and less severe due to humoral immunity from prior infection.
Patients are more contagious during a recurrence.
Buprenorphine
Is a partial opioid agonist that has low intrinsic activity for opioid mu receptors, however it binds with high affinity (potency) and can prevent binding of other opioid medications ,therefore it acts as opioid receptor antagonist in the presence of full opioid agonist and can precipitate withdrawal in opioid tolerant patients with chronic pain.
Rickets features
Its charactrized by inadequate calcium and phosphorus for the bone, and is charactrized by an excess of unmenarilized osteoid matrix and epiphyseal cartilage (growth plate).
- clinical manifestation vary with age. Prior to ambulation, frontal bossing, craniotabes and costochondral junction widening from cartilage overgrowth are apparent.
- once weight bearing which may be delated due to decreased muscle tone, patients have lateral femoral and tibial bowing. Genu varum.
Digoxin action on the heart for the treatment of Atrial fibrillation
Digoxin slows the ventricular rate during AF primarily by increasing parasympathetic tone which leads to inhibition of AV nodal conduction.
-it slows the AV conduction in AF and atrial flutter with RVR(rapid ventricular response)
Fluphenazine
Its first generation antipsychotic(FGA) known as typical or conventional antipsychotics .
-FGAs are classifies according to potency which requires the minmal dose to produce an effect. Low potency FGA primarily causes non-neurological side effects associated with histaminergic, cholinergic, and noradrenergic blockade.
These drugs are highly sedating and often causes anticholinergic side effects and orthostatic hypotension.
-high potency FGAs dosed in one to tens of milligrams are assoicated primarily with neurological side effects, or extrapyramidal symptoms due to potent D2 antagonism in the nigrostriatal pathway.
-low potency drugs example is chlorpromazine and high potency drug such as fluphenazine, and haloperidol.
Side effects of typical antipsychotic drugs
Low potency first generation typical:
Sedation, anticholinergic, orthstatic hypotension
High potency :
Extrapyramidal like acute dystonia, akathisia, parkinosnism., tardive diskynesia
Kawasaki disease
Medium sized arteries vasculitis, affects young children typically, <5 years and occurs most commonly in patients with asian ethnicity.
The diagnosis is based on fever for >5 days and 4 of the following
1. Bilateral nonexudative conjuctival infection (erythema)
2. Cervical lymphadenopathy
3. Mucositis: erythema of the palatine mucosa, fissured erythmatous lips, strawberry tongue.
4. Extremity changes: edema of the hands and feet, erythema of palms and soles, and desquamation of the fingertips
5. Rash: polymorphous erythmatous rash on the extremities that spreads centripetally to the trunk.
What is the difference between dysplasia and carcinoma
Dysplasia is a reversible process that doesnt necessarily proceed to cancer.
-low grade dysplasia doesnt involve the entire thickness of epithelium.
-high grade dysplasia is seen throughout the entire epithelium, but doesnt penetrate the basment membrane.
-
Pramipexole
Its a dopamine agonist used in parkinson disease, its nonergot compound (not from ergot fungi)
Milky plasma that forms a creamy appearing supernatant upon standing , with low LPL activity.
Familial chylomicronemia (type I hypoerlipoproteinemia) , an autosomal recessive condition most often caused by LPL deficiency.
- without sufficient LPL activity the body is unable to clear dietary lipid loads due to defective hydrolysis of serum TAG especially chylomicrons.
- pts present with familial chylomicronemia syndrome present in childhood with marked hypertriglyceridemia, recurrent acute pancreatitis, lipemia retinalis and eruptive xaanthomas.
Pituitary apoplexy
Acute intrapituitary hemorrhage (occurs most often in patients with preexisting adenoma)
Presentation: severe headache, bitemporal hemianopsia, opthalomplegia, panhypopituitarism.
Diagnosis: -neuroimaging shows pituitary enlargement and signs of hemorrhage.
Treatment: glucocorticoids replacement, surgical decompression to treat persistent visual and oculomotor symptoms.
Juvenile hemangioma (strawberry) pattern
These lesion consist of unencapsulated aggregates of closely packed, thin walled capillaries. Strawberry hemangioma are benign and quite common occurring in 1/200 births. They may be multiple and can be found in the skin, subcutaneous tissues, oral mucous membranes, or lips.
-capillary hemangioma may also occur in the liver, spleen and kidneys. Like most hemangioma these are present at birth and initially grow in proportion to the child. These lesions regress spontaneously at or before puberty. Typically they begin to fade between the ages 1-3 years. In 75%-95% of cases these woill have regressed completely by the age 7.
Granulosa cell tumor of the ovary
Large unilateral adnexal mass, with increased estrogen and inhibit production.(they can present as endometrial hypoerplasia)
It comprises approx 5% of all ovaries tumors and are primarily present in postmenopausal women.
They are classified as sex-cord-stromal tumors.
-granulosa cells have a gland like appearance with a pink eosinophilic center and coffee bean nuclei.
-the histolofy of the tumor consists of call-exner bodies which are cuboidal granulosa cells and yellow theca cells with lipid.
Elastin
Its a fibrous connective tissue protein that provides elasticity to the skin, blood vesseles and pulmonary alveoli.
The fibers can stretch to several time their length and recoil back once stretching force withdrawn.
-elastin similar to collagen synthesized as a large polypeptide precursor composed of about 700 mostly nonpolar amino acids (glycine, valine , alanine).
-elastic also contains proline and lysine residues, however in contrast to those found in collagen, few of these amino acid are hydroxylated.
-after tropoelastin is formed, its secreted into the extracellular space where it interacts with microfibrils (fibrillin) that function as a scaffold. Next lysl oxidase oxidatively deaminates some of the lysine residues facilitating the formation of desmosine cross links between neighboring polypeptides. These cross links acounts for rubber like properties of elastin
If a neonate doesn’t receive any medication or vaccination at birth comes with intracranial bleeding what is the etiology
Vitamin K deficiency
