Uworld31 Flashcards
Mitral valve prolapse with regurgitation is the most common predisposing condition for?
native valve infective endocarditis in developed nations. Rheumatic heart disease remains a frequent cause of IE in developing nations.
Relative risk reduction formula
(absolute riskcontrol - absolute risktxt )/ absolute riskcontrol
What is sodium nitroprusside?
a short acting agent that causes balanced vasodilation of the veins and arteries to decrease both left ventricular preload and afterload.
The balanced vasodilation allows for maintenance of stroke volume and cardiac output at a lower LV pressure (lower cardiac work)
What is seen in a clostridioides difficle infection?
associated with yellow-white, patchy pseudomembranes on the bowel mucosa. These pseudomembranes consists of a neutrophil-predominant inflammatory infiltrate, fibrin, bacteria, and necrotic epithelium.
Patients may develop a non obstructive colonic dilation known as toxic megacolon, which can lead to colonic perforation.
MOA of class II antiarrhythmic drugs (amiodarone, sotalol, dofetilide)
predominantly block potassium channels and inhibit the outward potassium currents during phase 3 of the cardiac action potential, thereby prolonging repolarization and total action potential duration.
MOA of emicizumab?
Hemophilia A is an X-linked disorder associated with a deficiency of factor VIII.
Emicizumab-a bispecific, monoclonal antibody- mimics the activity of factor VIII by binding to both factor IXa and factor X, bringing them into close proximity to allow for factor X activation.
What is CREST syndrome (limited scleroderma)?
manifests with calcinosis, Raynaud’s phenomenon, esophageal dysmotility, sclerodactyly and telangiectasias.
Anti-centromere antibodies are found in about 40% of patients with CREST syndrome.
Anti-DNA topoisomerase (Scl-70) antibodies are highly specific for systemic sclerosis.
What is a complication of untreated group A streptococcal pharyngitis?
Acute rheumatic fever.
Rheumatic heart disease is the most common cause of acquired valvular heart disease and cardiovascular death in developing countries.
The incidence of acute rheumatic fever and rheumatic heart disease has been reduced in industrialized nations with prompt treatment of streptococcal pharyngitis with penicillin.
What is thrombotic thrombocytopenic purpura?
a thrombotic microangiopathy resulting in microangiopathic hemolytic anemia and thrombocytopenia, findings that are essential in making the diagnosis.
It is triggered by severe deficiency in ADAMTS13 levels.
Long term acid suppression with proton pump inhibitors may be associated with an increased risk of?
osteoporotic fractures, possibly due to decreased calcium absorption.
Other meds associated with an increased risk of osteoporosis include glucocorticoids, aromatase inhibitors, and anticonvulsants that induce cytochrome P450.
A stroke involving the middle cerebral artery often leads to?
contralateral hemiparesis and/or hemisensory loss.
If it is in the non dominant (typically right) hemisphere, hemineglect and an unawareness of the condition are often present; aphasia is absent
What is pulmonary fibrosis?
presents with gradual onset progressive dyspnea, nonproductive cough, fatigue, eventual weight loss, and bilateral reticulonodular opacities on chest xray.
Pulmonary function tests reveal a restrictive pattern.
Patients with rheumatoid arthritis can develop interstitial lung diseases, both from the pulmonary manifestations of the disease itself and from certain therapies (eg, methotrexate, cyclophosphamide, sulfasalazine)
What can treat the behavioral and psychotic manifestations of delirium?
Delirium may manifest as acute changes in cognition and behavior.
When nonpharmacological interventions are ineffective, low dose antipsychotics (eg, haloperidol) are the meds of choice to treat the behavioral (eg, severe agitation) and psychotic manifestations of delirium.
What is seen on Tzanck smear for herpes?
Herpes simplex virus is a common, sexually transmitted infection marked by the formation of painful genital ulcers.
Tzanck smear can reveal the characteristic cytopathic effects of the virus, inclduing multinucleated giant cells, ground glass intranuclear inclusions, acantholytic cells, keratinocyte ballooning, and nuclear molding.
What are the labs in hemophilia?
an X-linked recessive coagulopathy that presents with intramuscular hemorrhage, hemarthroses, and delayed bleeding after procedures.
Lab results show partial thromboplastin time prolongation; other tests of hemostatic function are generally normal.
The absence of normal enteral stimulation in patients receiving total parenteral nutrition leads to?
decreased cholecystokinin release, biliary stasis, and increased risk of gallstones.
Resection of the ileum can also increase the risk of gallstones due to disruption of normal enterohepatic circulation of bile acids.
What is myelodysplastic syndrome?
a clonal hematologic neoplasm marked by >1 cytopenias and cellular dysplasia (eg, oval macrocytic erythrocytes, hyposegmented granulocytes).
Bone marrow evaluation usually reveals a hypercellular marrow, a mild or moderate increase in myeloblasts (<20% of total cells), and dysplastic erythrocytes/granulocytes.
Cholestatic liver disease can cause?
malabsorption and nutritional deficiencies of fat-soluble vitamins.
What is cilostazol?
Symptomatic management of peripheral artery disease includes a graded exercise program and cilostazol.
Cilostazol is a phosphodiesterase inhibitor that inhibits platelet aggregation and acts as a direct arterial vasodilator.
Patients with PAD should also receive an antiplatelet agent (aspirin or clopidogrel) for secondary prevention of coronary heart disease and stroke.
Myocardial infarction that causes ischemia of the papillary muscle or nearby left ventricular wall can result in?
acute mitral regurgitation with development of a new systolic murmur.
Timely restoration of blood flow can improve papillary muscle dysfunction and lead to resolution of the regurgitation.
When does a hiatal hernia occur?
Occurs when contents of the abdominal cavity herniate through the diaphragm at the esophageal hiatus into the thoracic cavity.
When does a sliding hiatal hernia occr?
occur due to laxity of the phrenoesophageal membrane, leading to herniation of the gastroesophageal unction and proximal stomach, whereas paraesophageal hernias occur due to defects in the membrane, resulting in the gastric fundus herniation.
What is a granuloma?
Granulomas are characterized by a large number of epithelioid macrophages that may fuse together to form multinucleated cells (Langhans giant cells) surrounded by a band of lymphocytes.
Granuloma formation involves chronic Th1 and macrophage activation in response to a difficult-to-eradicate antigen.
High dose IL-2 therapy can be used for?
IL-2 is endogenously produced by CD4, CD8, and natural killer cells and has strong proinflammatory and some anti-inflammatory effects.
High-dose IL-2 therapy can be used for advanced renal cell carcinoma and metastatic melanoma; this can lead to long-lasting remission due to increased cytotoxic activity of NK cells against the tumor.
In the forearm, the median nerve courses between?
the humeral and ulnar heads of the pronator teres muscle.
Compression proximal to the takeoff of the palmar cutaneous branch (eg, between the heads of the pronator teres) results in sensory loss over the lateral palm and thenar eminence plus the palmar aspect of the first 3 1/2 digits.
What is a Reed-Sternberg cell?
The presence of Reed-Sternberg cells on lymph node biopsy is a diagnostic feature of classic Hodgkin lymphoma.
RS cells have abundant cytoplasm, a multilobed nucleus or multiple nuclei, and inclusion-like nucleoli.
What is euthyroid sick syndrome?
a common pattern of thyroid function markers seen in severely ill patients.
It is characterized by decreased conversion of T4 to T3 in peripheral tissues.
Initial findings include a low T3 level, but later, T4 and thyroid-stimulating hormone levels may also decrease.
ESS may represent a mild central hypothyroid state, which functions to minimize catabolism in severe illness.
What is diabetic mononeuropathy?
Diabetic mononeuropathy often involves cranial nerve III.
It is caused by predominantly central ischemia, which affects the somatic nerve fibers but spares peripheral parasympathetic fibers.
Symptoms include ptosis, a “down and out” gaze, and normal light and accommodation reflexes.
What are the sodium and chloride levels in cystic fibrosis?
Patients with cystic fibrosis produce eccrine sweat with higher than normal concentrations of sodium and chloride.
Exposure to high temperature or exercise can lead to hyponatremia and hypochloremia due to excessive sodium chloride loss through sweat; therefore, salt supplementation is recommended.
What is toxic megacolon?
a well recognized complication of ulcerative colitis.
Patients typically present with abdominal pain/distention, bloody diarrhea, fever, and signs of shock.
Plain abdominal x-ray is the preferred diagnostic imaging study.
Barium contrast studies and colonoscopy are contraindicated due to the risk of perforation.
What med can be used to control the symptoms of carcinoid syndrome?
Carcinoid syndrome may accompany extraintestinal metastases of gastrointestinal carcinoid tumors.
Octreotide is a synthetic somatostatin analog used to control the symptoms of carcinoid syndrome.
What is the vaccine for Neisseria meningitidis?
Antibodies against the polysaccharide capsule of Neisseria meningitidis provide immunity against this pathogen.
Quadrivalent meningococcal vaccines contain capsular polysaccharides from major serotypes (A, C, Y, and W) of N meningitidis.
Serotype B vaccinations use recombinant proteins.
What is the most common cause of skin and soft tissue abscess (eg, furuncle)?
Staph aureus.
Treatment of the abscess with incision and drainage and antibiotics can eliminate the local infection but does not eliminate colonization of the anterior nares and skin. Therfore, recurrent infections are common.
What is P50?
P50 refers to the partial pressure of oxygen at which hemoglobin is 50% saturated.
Hemoglobins with high oxygen affinity have a decreased P50 that is represented by a leftward shift of the oxygen dissociation curve. The reduced ability to release oxygen within the peripheral tissues leads to renal hypoxia, increased erythropoietin synthesis, and compensatory eythrocytosis.
What is multiple endocrine neoplasia type 2B?
characterized by medullary thyroid cancer, pheochromocytoma, marfanoid habitus, and oral and intestinal mucosal neuromas.
What is obstructive sleep apnea?
the most common sleep-related breathing disorder, is characterized by recurrent obstruction of the upper airways.
Relaxation of the oropharyngeal and/or soft palate musculature during sleep results in a functional collapse of the airway, producing periods of reduced (hypopnea) or absent (apnea) airflow despite continued breathing efforts.
What is the two sample t tes?
statistical method commonly employed to compare the means of 2 groups of subjects.
What treats severe hypoglycemia?
Severe hypoglycemia causing impaired conciousness can be treated by a caregiver or bystander with injectable or intranasal glucagon.
Glucagon rapidly corrects hypoglycemia by increasing hepatic glycogenolysis, resulting in the release of glucose from preexisting hepatic glycogen stores.
What muscles attach to the clavicle?
The clavicle is commonly fractured in children after a fall on an outstretched arm.
In a distal clavicle fracture, the deltoid muscle and the weight of the arm cause inferolateral displacement of the distal fragment, whereas the sternocleidomastoid and trapezius muscles cause superomedial displacement of the proximal fragment.
What artery needs to be ligated for postpartum hemorrhage due to uterine atony?
The internal iliac artery (hypogastric artery) supplies blood to the pelvis, including the uterus via the uterine artery.
Therefore, bilateral ligation of the internal iliac artery is a potential surgical management option for postpartum hemorrhage due to uterine atony.
