NBME 30 questions with rated solutions

NBME 30 questions with rated solutions difference b/w Kwashiorkor & Marasmus - kwashiorkor (edematous malnutrition): marasmus PLUS EDEMA - marasmus (WASTING SYNDROME): skin lesions, fatty liver, acute protein-energy malnutrition with decreased arm circumference, weight per length or BMI deformation disruption in organ morphogenesis occurring AFTER embryonic period; extrinsic force limits normal organ development vascular changes in chronic HTN - hyaline arteriolosclerosis: protein deposition in vessel walls - hyperplastic arteriosclerosis (arteriolitis): concentric thickening of vessel wall w/ laminar appearance caused by proliferation of smooth muscle cells - commonly affects renal arterioles Nodular glomerulosclerosis assoc w/ diabetic nephropathy & amyloidosis supraoptic nucleus responsible for ADH secretion from pituitary & urine concentration anterior hypothalamic nucleus thermoregulation (cooling) arcuate hypothalamic nucleus appetite stimulation dorsomedial hypothalamic nucleus regulation of feeding & circadian rhythm lateral hypothalamic nucleus promotes appetite (GHRELIN) posterior hypothalamic nucleus thermoregulating (heating) ventromedial hypothalamic nucleus satiety (LEPTIN) osteopetrosis excessive mineralization of bone & failure of osteoclastic resorption - mutation in macrophage colony stimulating factor achondroplasia human dwarfism - AD mutation in fibroblast growth factor receptor 3 (FGFR3) gene porphyria cutanea tarda severe cutaneous photosensitivity with blistering & hyperpigmentation after exposure to sunlight - decreased activity of uroporphyringoen decarboxylase enzyme in the production of HEME CD8+ T lymphocytes responsible for CLEARING a virus - class I MHC receptors present a virus to CD8+ T cell on an APC - CD8+ T cell has a specific TCR for the virus; responds by secreting inflammatory mediators (to attract other cells) perforin/granzyme or interacting with Fas/FasL to trigger apoptosis Class II MHC are on the surface of antigen-presenting cells (APCs), including B cells - trigger CD4+ T cells, which recruit CD8+ cytotoxic T cells PKU deficiency of phenylalanine hydroxylase - supplementation of TYROSINE is required for synthesis of catecholamines (norepinephrine, epinephrine & dopamine) leuprolide GnRH agonist used for the treatment of prostate cancer - decreased LH & testosterone release production of progesterone during pregnancy - first 7-10 weeks: CORPUS LUTEUM (stimulating by hCG from placenta) 10 weeks: placenta Chronic granulomatous disease X-linked mutation affecting NADPH oxidase causing dysfunctioning neutrophils and oxidative burst - recurrent infections with catalase (+) organisms: S. aureus, Aspergillus & Nocardia MPO deficiency Recurrent candida infections Wiskott-Aldrich syndrome mutation in WAS gene; abnormal cytoskeleton of B & T cells - Eczema, recurrent respiratory infections, thrombocytopenia Chediak-Higashi syndrome Mutation in LYST (lysosomal trafficking gene regulator) which causes accumulation of large cytoplasmic granules that cannot fuse with lysosomes - increase of bacterial, viral, and fungal infections - Albinism, photophobia, silver hair Coccidioidomycosis fungal infection endemic to Southwest US & California - respiratory illness, fever, fatigue, cough, arthralgia Lambert-Eaton Myasthenic Syndrome (LEMS) Auto-Immune; antibodies formed against voltage gated Ca2+ channels at NMJ; IMPAIRED PRESYNAPTIC ACH RELEASE - Sx: skeletal muscle weakness in limbs (improves w/ activity) - paraneoplastic syndrome assoc w/ small cell lung carcinoma round ligament binds uterus to labia majora - commonly leads to pain during pregnancy mesothelioma pleural effusion & scalloped pleural density; thick, firm, white pleural tumor - interstitial fibrosis - ASBESTOSIS: working in a shipyard, roofing & plumbing biggest risk factor for complications w/ use of OCPs tobacco smoking in patients 35 years - contraindications: history of DVT, PE, stroke, MI, HTN, migraine w/ aura, cirrhosis & current breast cancer Pores of Kohn small openings in the alveolar walls that allow gases, fluid, macrophages & BACTERIA to travel between the alveoli Osgood-Schlatter disease inflammation or irritation of the tibia at its point of attachment with the PATELLAR TENDON - common in YOUNG ATHLETES - focal pain & tenderness w/ application of tension to tibial tubercle increased risk of liver injury from acetaminophen + alcohol alcohol leads to induction of P450 enzymes that convert acetaminophen to NAPQI - NAPQI can cause hepatotoxicity childhood perception of death - 3 years: no understanding of death - age 3-5: death is temporary & reversible - 5 years: all living things die (irreversible & inevitable) Weber syndrome (lower midbrain stroke) stroke of paramedic branches of PCA - ipsilateral CN III palsy (diplopia, ptosis, primary gaze palsy, pupillary constriction defects) - contralateral hemiparesis with UMN pattern dysfunction gerstmann syndrome stroke of angular gyrus - agraphia, acalculia, finger agnosia & left sided disorientation Horner syndrome lesion of upper spinal cord interrupting sympathetic supply to ipsilateral face - ptosis, mitosis, anhidrosis Waardenburg Syndrome autosomal dominant disorder of abnormal neural crest development → abnormal melanoblasts - white forelock, PATCHY depigmentation iridic heterochromia & deafness - eyes may be laterally displaced failure of internalization of melanin granules by keratinocytes NONPATCHY albinism, no hearing loss (vs. Waardenburg) maintenance of constant GFR in the setting of renal artery constriction increased EFFERENT arteriole resistance → activation of RAAS rapid plasma reagent (RPR) false positive SLE → antiphospholipid antibodies will yield false (+) RPR/VDRL are used to detect antibodies against syphilis cold agglutinins Mycoplasma pneumoniae, EBV - marker of HEMOLYSIS heterophiles antibodies Infectious mononucleosis (EBV) p24 antigen HIV1/2 glucose-independent insulinotrophic peptide (GIP) secreted by K cells in the duodenum & jejunum - decrease gastric acid production & stimulate insulin release from pancreas - secreted in response to glucose/fatty acids to lower blood sugar ureteral constriction hydronephrosis - vesicoureteral junction, crossing point over COMMON ILIAC ARTERY or ureteropelvic junction ^ renal calculi tend to lodge at these 3 locations most common artery to obstruct the ureter COMMON ILIAC 21-hydroxylase deficiency excessive androgens, low aldosterone & cortisol - female: hypoaldosteronism & virilization during infancy (develops male characteristics) - male: precocious puberty in childhood