Download NBME CBSE REAL EXAM 200 QUESTIONS AND ANSWERS LATEST 2023-2024 (usmle step 1)MEDICAL EXAM and more Study Guides, Projects, Research Health sciences in PDF only on Docsity!
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Type II pneumocytes - ANSWER: surfactant (lecithin) Proliferate after injury Type I progenitors Neonatal Respiratory Distress Syndrome Polio live v killed vaccine - ANSWER: Killed = Salk = IgG Live = Sabin = IgG + IgA
- can be shed in feces Neonatal Respiratory Distress: Etiology + Tx - ANSWER: Maternal DM (high insulin) or C-section (low cortisol) TX: dexamethasone before birth Lung maturity determined with - ANSWER: Amniocentesis of Phospholipids (*type II pneumocytes) L >> S Type I pneumocytes - ANSWER: Squamous gas diffusion Elastase in lungs - ANSWER: macrophage: lysosomes PMN: azuronphilic granules Elastin stretches and recoils due to - ANSWER: Lysine interchain crosslinks air pressure and intrapleural pressure at FRC - ANSWER: Air pressure = 0 Intrapleural pressure = - 5 Pulm Vasc Resistance is lowest during - ANSWER: Exhale of Tidal Volume
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Lung Compliance is decreased by - ANSWER: LHF, pulmonary edema, pulmonary fibrosis Lung Compliance is increased by - ANSWER: emphysema, age Obesity affects ERV and FRC - ANSWER: DECREASE ERV & FRC Blood flow/min (pulmonary v systemic) - ANSWER: pulmonary = systemic Anatomic pulmonary shunting - ANSWER: Bronchial circulation causes decreased PO2 in LA/LV than in pulmonary capillaries More ventilation is at the - ANSWER: BASE O2-Hgb dissociation LEFT shift - ANSWER: basic, cold, low 2,3 BPG low pO2 (compensatory erythrocytosis) O2-Hgb dissociation RIGHT shift - ANSWER: low pH, high 2,3BPG, high T HOT, ACIDIC CO2 transport to lungs - ANSWER: carbonic anhydrase Cl shift Haldane: CO2 released to lung (Bohr: O2 release to tissue) CO poisoning causes - ANSWER: carboxyhemoglobin no affect on PaO
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Restrictive/Interstitial Lung Disease: A-a, FVC, FEV1, EFR - ANSWER: Airway widening due to radial traction from fibrosis increase Aa decreased FVC & FEV Increased EFR Sarcoidosis - ANSWER: Th1 noncaseating granulmona bilateral hilar adenopathy increased ACE increased IL2, IFNg 1 - a-hydroxylase in macrophages: vit D --> HyperCa Hyper Ca causes - ANSWER: stones, thrones, groans, psych overtones 1 - a-hydroxylase in macrophages - ANSWER: PTH independent conversion of Calcifediol to calcitriol (bioactive Vit D) Vit D --> Hyper Ca Idiopathic pulmonary fibrosis - ANSWER: Honeycomb pattern loss of Type 1 pneumocytes hyperplasia Type II pneumocytes Goodpasture - ANSWER: HS II Auto-Ab against BM destroys lung alveoli (restrictive) and renal glomeruli Obstructive Lung Disease - ANSWER: DECREASED FEV1, Decreased FVC increased RV, FRC, TLC **different shape COPD - ANSWER: PMN, mo, CD
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
V/Q mismatch: O2 induced hypercapnia; physio dead space Myeloperoxidase causes - ANSWER: Green sputum/pus Do not give O2 supplement to - ANSWER: COPD patient Decreased stimulation of carotid bodies = decreased RR TX COPD with - ANSWER: Fluticasone (glucocorticoid) inhibit cellular reaction a1-antitrypsin deficiency - ANSWER: Serine protease inhibitor LIVER LUNG: inc PMN elastase --> emphysema Asthma dx - ANSWER: Methacholine (maCh) challenge = induce bronchoconstriction to reduce FEV
- test = Airways ARE reactive B2 agonist MOA - ANSWER: B2 (Gs) --> AC --> increase cAMP Corticosteroid MOA - ANSWER: inhibit cytokine synthesis suppress T lymphocyte mACh Antagonist ("tropium") MOA - ANSWER: inhibit Vagal via ACh --> decreased Ca
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Warfarin Fat embolism syndrome - ANSWER: Long bone/pelvic fracture --> neuro, hypoxemia, rash Fat microglobules in pulmonary arterioles Spontaenous pneumothorax - ANSWER: nontraumatic* rupture of subpleural blebs* **20 yo thin TALL man who smokes DECREASED PRELOAD Tension pneumothorax - ANSWER: Treachea deviates REQUIRES INTUBATION ARDS - ANSWER: bilateral infiltrate **PANCREATITIS RISK
- EXUDATIVE (capillary permeability)
- Proliferative (collagen)
- Fibrotic (pulmonary fiborsis + HTN) What are the risks from ARDS - ANSWER: Sepsis Pancreatitis Pneumo cystic fibrosis genetics - ANSWER: dF508 frameshift CFT protein - post-tln HypoNa Cystic Fibrosis complications - ANSWER: Dec Vit A --> Pancreatic (squamous metaplasia) Def Vit E --> Neuromuscular, hemolytic anemia Def *Vit K *--> Intracranial hemorrhage
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Meconium Ileus; No Vas deferns; Digital clubbing DEATH FROM PNEUMO Hemorrhagic infarct is what color and why - ANSWER: RED Dual blood supply Empyema - ANSWER: Infected exudative pleural effusion Meniscus opacity Increased LDH COMPLICATES PNEUMO Lobar pneumonia - ANSWER: consolidation Ex: strep, legionella --> Red (3-4 d) --> Grey hepatization (5-7d) --> Resolution (Type II regen in 8 d) Broncho Pneumonia - ANSWER: Patchy ex: Staph, Strep, Kleb, H flu Interstitial Pneumonia - ANSWER: Alveolar walls Ex: Mycoplasma, Chlamydia, Legionella, RSV/CMV/flu/adeno Tuberculosis - ANSWER: Th1: IFNg --> activates Macrophage (CD14): TNF-a Lung Harmatoma - ANSWER: hyaline cartilage, fat, SMC lined by respiratory pneumoepithelium
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
hilar mass HyperCa --> PTHrP (stones, bones, groans, psych overtones) SCLC - ANSWER: neuroendocrine (*neural cell adhesion molecule) HORMONES: ACTH, ADH, Lambert Eaton Acute transplant rejection in lungs - ANSWER: perivascular mononuclear infiltrates in smalll bv Chronic transplant rejection in lungs - ANSWER: Bronchiolitis obliterans in small airways Gastroschisis - ANSWER: not covered by periotoneum poor GI function Omphalocele - ANSWER: Midline herniation covered by periotoneum normal GI function *Trisomy 13/18, CL/P Diverticulitis - ANSWER: outpouching of mucosa + submucosa **Dysphagia most diverticulitis are - ANSWER: FALSE (pulsion, Zenker) Meckel Diverticulum - ANSWER: TRUE = traction
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
bulge at ileum Mallory Weiss - ANSWER: Mucosal tears due to intraabdominal pressure Boerhaave - ANSWER: *Transmural *distal rupture due to increased intraabdominal pressure Esophagel cancer in upper 2/3 - ANSWER: SCC Esophageal cancer in lower 1/3 - ANSWER: Adenocarcinoma Splenic vein thrombosis causes gastric varices where - ANSWER: fundus esophageal dysfunction can be due to enlarged - ANSWER: left atrium GERD - what happens to LES tone - ANSWER: DECREASED LES tone Achalasia - what happens to LES tone - ANSWER: INCREASED LES tone Krukenberg tumor - ANSWER: gastric cancer signet ring cells: mucin displaces nucleus **spreads to ovary Zollinger-Ellison tumor - ANSWER: Gastrin secreting causes PUD dx: increased secretin Vipoma - ANSWER: watery diarrhea + hypoK tx: octreotide
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Secretin is released due to - ANSWER: low pH fatty acid Pepsin is from - ANSWER: Chief cells Pepsin is released due to - ANSWER: Vagal (ACh) low pH (digest protein) Gastric acid is from - ANSWER: Parietal cells Gastric acid is released due to - ANSWER: Gastrin: CCKb-R --> ECL/mast --> histamine (cAMP) Vagal (ACh) Somatostatin is from - ANSWER: D cells (INHIBITS gastric acid & pancreatic/gb contraction) Somatostatin action - ANSWER: Inhibit gastric acid and pancreatic/gb contraction Somatostatin is released due to - ANSWER: Low pH, Vagal (inhibit gastric acid & panc/gb contraction) Cholecystokinin is from - ANSWER: I cells (duodenum) Cholecystokinin causes - ANSWER: pancreatic/gb contraction
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
CCK is released due to - ANSWER: fatty acids and aa VIP causes - ANSWER: increase pH via H2O/e excretion Relax sphincter NO in GI causes - ANSWER: relaxation of LES Ghrelin causes - ANSWER: increased appetitie GIP/GLP is released from - ANSWER: L cells GIP/GLP causes - ANSWER: Dexcrease H Increase insulin Acute gastritis is caused by - ANSWER: NSAID (low PGE2 in PMN) *Burns *= Curling (hypovolemic) *Brain *= Cushing (high Vagal, ACh) H pylori gastritis is located - ANSWER: antrum H pylori gastritis increases risk for - ANSWER: MALT or adenocarcinoma H pylori gastritis histo - ANSWER: patchy infiltrate + multifocal atrophy Autoimmune gastritis is located - ANSWER: body/fundus Autoimmune gastritis can risk - ANSWER: pernicious anemia H pylori duodenal PUD tx - ANSWER: *(use 2): *Amoxicillin / clarithromycin / metronidazole / tetracycline
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
tx: GERD, Gastroparesis Loperamide - ANSWER: Mu agonist without CNS penetration SLOW motility Enteric bacteria produce what vitamins - ANSWER: Vit K and Folate Watershed areas in GI - ANSWER: Rectosigmoid + Splenic flexure Fat malabsorption stain with - ANSWER: Sudan III What is absorbed at brush border - ANSWER: D-xylose and lactose Duodenal atresia is associated with - ANSWER: Down Syndrome Duodenal atresia - ANSWER: failure of recanalization Double bubble (tri21) Jejunum/Ileum atresia - ANSWER: Vascular occlusion Apple peel Jejunum/Ileum atresia example - ANSWER: Gastrocschesis Colonic Atresia example - ANSWER: Hirschsprung Colonic Atresia - ANSWER: submucosal of RECTUM = Meissner plexus absent
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Abetalipoproteinemia - ANSWER: foamy cytoplasm at villi tips NO APO-B
- No VLDL or Chylomicron Mesenteric Ischemia - ANSWER: SMA (A fib embolus) --> Extreme pain = Food aversion Lactose intolerance - ANSWER: low stool pH high Breath H high Stool osmolality Celiac - genes - ANSWER: Gliadin HS IV * HLA-DQ2/ Anti-tTG (IgA) Antiendomysial Celiac malabsorption complication - ANSWER: Malabsorption of vit D in duodenum decreased Ca/PO high PTH --> Osteomalacia/rickets Celiac association - ANSWER: Dermatitis Herpetiformis Dermatitis herpetiformis - ANSWER: IgA in dermal papilla (Celiac) Crohns - ANSWER: ASCA Fistula; Transmural thickening Non-caseating granuloma Bile acid malabsorption (TERMINAL ILEUM)
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Colitis becomes carcinoma how - ANSWER: multifocal poorly differentiated tumors early p53/late APC HNPCC/Lynch - ANSWER: microsatellite instability MSH2/MLH1 = mismatch repair HEREDITARY colorectal, endometrial, ovarian LN drainage proximal to dentate - ANSWER: (UPPER RECTUM) Inferior Mesenteric Internal Iliac LN drainage Distal to dentate - ANSWER: (ANUS) Inguinal Hemorrhoids - internal - ANSWER: above dentate PAINLESS superior rectal --> inferior mesenteric v --> PORTAL Hemorrhoid - External - ANSWER: below dentate PAINFUL Inferior rectal --> internal pudendal = IVC Indirect hernia is common in - ANSWER: child Indirect hernia is a - ANSWER: fluctuant hydrocele due to patent processus vaginalis
LATEST 2023-2024 (usmle step 1)MEDICAL EXAMINATION
Indirect hernia is located - ANSWER: through inguinal ring into scrotum LATERAL to epigastrics Direct hernia is due to - ANSWER: weakened transversalis fascia Direct hernia is located - ANSWER: Hesselbach triangle MEDIAL to epigastrics Femoral hernia is common in - ANSWER: female What becomes the main pancreatic duct - ANSWER: Ventral pancreatic bud Annular pancreas is caused from - ANSWER: abnormal ventral pancreatic bud MIGRATION Encircles duodenum Vit a deficiency caused from - ANSWER: squamous metaplasia of pancreatic ducts OR biliary obstruction What activates trypsin - ANSWER: Enteropeptidase Pancreas K Channels are sensitive to what - ANSWER: ATP Epi does what to insulin - ANSWER: a2 = inhibit insulin B2 = stimulate insulin Acute pancreatitis is due to - ANSWER: **Gallstones **Alcoholism
