Blocks 37, 38 Flashcards Preview

UWORLD STEP 1 > Blocks 37, 38 > Flashcards

Flashcards in Blocks 37, 38 Deck (68):
1

Enterococcus is a component of normal flora where in the body?

Colonic flora

Urogenital Flora

 

2

Enterococcal endocarditis usually occurs in elderly men who have recently undergone what procedures?

Genitourinary (cystoscopy)

Gastrointestinal (colonoscopy)

Obstetric procedures (in women)

3

Postitive VDRL of the spinal fluid indicates what?

Neurosyphillis

4

Lancinating pains, parasthesias, loss of vibratory and position sensation. Loss of proprioception is usually compensated for by visual clues, but sensory ataxia prevails in the dark. Areflexia and loss of bladder function can also occur. Possibly Argyll Robertson pupils and +Romberg sign.

Tabes Dorsalis as a result of neurosyphillis

Damage to dorsal roots in dorsal columns

5

Progressive signs and symptoms like bleeding from thrombocytopenia (epistaxis, bruising), pallor and fatigue from anemia, and bacterial infections from leukopenia/neutropenia. Splenomegaly is ABSENT due to a lack of available hematopoietic progenitor cells and therefore a lack of extramedullary hematopoiesis.

Aplastic anemia

Pancytopenia with bone marrow hypocellularity

6

What is the pathogenesis of muscular dystrophy?

Deletions of dystrophin gene that encodes the dystrophin protein on X chromosome p21.

Loss of dystrophin leads to cellular injury (myonecrosis)

X linked recessive

7

What is given to patients with moderate to severe allergic asthma that is uncontrolled?

Oral glucocorticoids

Omalizumab (Anti-IgE antibodies) - to reduce dependency on both oral and inhaled steroids

8

Approximately 90% of left atrial thrombi are found within what area in patients with nonvalvular atrial fibrillation?

Left Atrial Appendage - a small saclike structure in the left atrium

9

What are the 3 most important predisposing factors for hypoglycemia in patients with type 1 diabetes?

1. Excessive Insulin Dose

2. Inadequate food intake

3. Physical activity/exercise

10

What gives rise to the collecting system of the kidney? (collecting tubules and ducts, major and minor calyces, renal pelvis, ureters)

Ureteric Bud

11

What gives rise to the glomeruli, Bowman's space, proximal tubules, loop of Henle, and distal convoluted tubules?

Metanephric Mesoderm (blastema)

12

What is the Reid Index?

Ratio of thickness of the mucous gland layer in the bronchial wall submucosa to the thickness of the bronchial wall between the respiratory epithelium and bronchial cartilage.

*sensitive measurement of mucous gland enlargement

*Elevations of the RI above the normal value of 40% = duration and severity of chronic bronchitis

13

Severe fatigue, splenomegaly (often causing early satiety/abdominal discomfort), hepatomegaly, anemia and bone marrow fibrosis

Primary Myelofibrosis

Atypical megakaryocytic hyperplasia (stimulates fibroblast proliferation) resulting in replacement of marrow space by extensive collagen deposition.

Peripheral smear = teardrop-shaped red blood cells (dacrocytes) and nucleated RBCs

GOF mutation of a non-receptor tyrosine kinase protein in hematopoietic cells, leading to persisten activation of signal transducers and activators of transcription (STAT) proteins. (JAK2)

14

Repetitive, rhythmic, involuntary movements of the tongue, lips, face, trunk, and extremeties

Orofacial dyskinesias (facial grimacing, lip smacking) are most common, but choreoathetoid movements of the trunk and limbs can also occur.

Tardive Dyskinesia

Chronic use of antipsychotic medications

15

What is the most common gastrointestinal abnormality associated with Down Syndrome?

Duodenal atresia - failure of recanalization of the duodenum; Bilious emesis and double bubble sign in first few days of life

 

Also, imperforate anus, hirshsprung disease, tracheoesophageal fistula, celiac disease

16

What is the equation for Filtration Fraction?

GFR/RPF

17

Unilateral facial pain that worsens with jaw movement, headache, ear discomfort (pain and muffled hearing in that ear)

Temporomandibular Disorder (TMD)

Mandibular nerve (trigeminal) causes the jaw pain and otologic symptoms

18

Prolactinomas cause what symptoms in women?

Amenorrhea and galactorrhea

Hypogonadism, anovulation, amenorrhea

Decreased estrongen:

Accelerated bone loss (high risk for pathological fractures)

Vaginal dryness

19

Digital clubbing, a thickening of the distal phalanges is a sign of what?

Fingers have a drumstick appearance, flattening of the nail folds, shininess of nail and distal portion of the finger.

HYPOXIA

Lung diseases: bronchiectasis, pulm HTN, lung cancer, TB, empyema

Heart: cyanotic congenital heart diseases, bacterial endocarditis

Other: IBD, hyperthyroidism, malabsorption

20

If the AV node is bypassed, what part of the ECG will be affected?

Wolff-Parkinson White Triad:

PR interval will be shortened

Widened QRS

Delta wave

21

1 month old with a history of persistent jaundice now having muscle rigidity, lethargy, and seizures. What is causing the hyperbilirubinemia?

Crigler Najjar - AR 

Genetic lack of UGT needed to catalyze bile glucuronidation

22

Adverse drug reaction that occurs due to known pharmacologic actions of a drug but at a lower dose than expected.

Exaggerated Drug Sensitivity

23

Unpredictable reaction to a drug due to genetic differences or complex metabolic interactions in certain patients

Idiosyncratic Drug Reaction

Ex: G6PD pt given primaquine --> oxidative cellular injury and nonimmune hemolytic anemia

24

Low doses of Dopamine vs. high doses of Dopamine have what effets on renal blood flow and cardiac output?

Low: Vasodilation;  Increased renal blood flow, increased cardiac contractility (increased CO)

High: Vasoconstriction;  decreased renal blood flow, decreased CO (increased afterload)

25

Flushed skin and mydriasis are symptoms from what type of blockade?

Muscarinic Receptor Blockade

26

Medications with Antimuscarinic effects

Atropine

TCAs

H1 receptor antagonists (diphenhydramine)

Neuroleptics

Antiparkinsonian drugs

27

Slowly progressive exertional dyspnea, dry cough, restrictive profile on pulmonary function testing (FVC 40% of the predicted value and a FEV1/FVC of 87%), interstitial fibrosis with cystic air space enlargement

Idiopathic Pulmonary Fibrosis

 

Patchy involvement with dense fibrosis

Alveolar wall collaps leads to honeycombing lined by hyperplastic type 2 pneumocytes or bronchiolar epithelium

*Predominant in the subpleural and paraseptal spaces

28

Microcytic anemia, constipation, mental status changes in the setting of construction work

Lead poisoning

 

Lead lines at gum-tooth line

Wrist drop or foot drop to peripheral neuropathy

Basophilic stippling on peripheral blood smear

29

Administration of what drug type will cause an increase in systolic and diastolic blood pressures and a reflexive (delayed) decrease in HR

Selective alpha 1 adrenergic agonist (phenylephrine, methoxamine)

30

Diagnostic criteria for Kawasaki Disease

Asian child under 5 y/o

Fever for at least 5 days plus 4 of the following:

Bilateral non-exudative conjunctival injection (erythema)

Cervical LAD

Mucositis: strawberry tongue, cracked lips, red throat

Extremity changes: edema of hands/feet, erythema of palms/soles, desquamation of fingertips

Rash: polymorphous (itchy) erythematous rash on extremities that spreads to the trunk

31

Patient with SLE plus prolonged activated partial thromboplastin time (aPTT) and false-positive rapid plasma reagin (RPR) test suggest what?

circulated antiphospholipid antibodies

32

Antiphospholipid antibody syndrome causes what adverse pregnancy outcomes?

Unexplained fetal loss

Preamture birth due to placental insufficiency or preeclampsia

33

What type of test is commonly used to determine if the means of 2 populations are equal?

Two-sample T test

34

Infant with normal development for a few months followed by progressive neurologic deterioration: weakness, hypotonia, developmental regression, seizures, blindness, and spasticity. PE shows macrocephaly and an abnormal startle reflex with acoustic stimuli. Cherry-red macula spot surrounded by a white macula (halo)

Tay-Sachs Disease

AR

Beta-hexosaminidase A deficiency resulting in the accumulation of GM2 ganglioside within lysosomes.

35

What is the initial insult in an aortic dissection?

Tear in the aortic intima that typically extends 1-5 cm in a transverse or oblique direction.

36

Bump below normal breast line that may swell or become tender similar to normal breast tissue before or during menses, pregnancy, and lactation. Hyperpigmentation, epidermal thickening

Accessory nipple

Failure of involution of the mammary ridge

37

Severe pruritus that slowly progresses over time. Especially prominant over palms and soles that may be unbearable at night. Fatigue. High direct bilirubin, Alk phos, and AST. 

Primary Biliary Cirrhosis (PBC) - autoimmune destruction of the intrahepatic bile ducts and cholestasis

Later: Hepatosplemomagaly, xanthomatous lesions in skin (eyelids), jaundice, steatorrhea, portal HTN, and osteopenia

 

Associated with Sjogren's syndrome, raynaud, scleroderma, autoimmune thyroid disease, hypothyroidism, celiac disease

38

Infant with a one sided scrotal enlargement that increases when he cries/strains. Present since birth. US shows a fluid collection around the testis. What is defective and what can happen as a result?

Failure of obliteration of the processus vaginalis leading to a persisten connection between the scrotum and the peritoneal cavity through the inguinal canal.

Can lead to an indirect inguinal hernia if the opening is large enough.

39

What are the 2 arrest points in female gametogenesis?

Prophase 1 of Meiosis 1 - primary oocytes prior to becoming a follicle for ovulation

Metaphase of Meiosis 2 - secondary oocytes prior to fertilization

40

Episodic sudden onset headache, tachycardia, diaphoresis, apprehensiveness, fine tremor. Severe HTN that may be paroxysmal or persistent. Symptoms resolve in a matter of moments but will occur again.

Pheochromocytoma

Symptoms from increased catecholamine secretion

Arise from neuroendocrine cells in adrenal medulla

41

What should be watched for when initiating an ACEI for the first time?

First-dose hypotension

Abrupt removal of the vasoconstrictive effects of angiotensin 2, resulting in decreased peripheral vascular tone and a precipitous drop in BP.

More likely in pts with high plasma renin activity like volume depletion or heart failure.

42

Ion pump failure due to ATP deficiency during cardiac ischemia causes what to happen intracellularly?

Accumulation of Na+ and Ca2+ intracellularly --> free water drawn into the cell --> cellular and mitochondrial swelling

43

What structures are penetrated when a suprapubic cystostomy is preformed?

Aponeurosis of abdominal wall muscles

Layers of superficial fascia, transversalis fascia, extraperitoneal fat

44

African American female with hilar adenopathy and pulmonary infiltrates + non-caseating granulomas on lung biopsy

Sarcoidosis

45

Granuloma formation is a manifestation of cell-mediated immunity driven by products of what?

Th1 type CD4 --> IL-2, and IFN-gamma --> stimulate Th1 type cell proliferation (IL-2) and macrophage activation (IFN-gamma) 

46

Beta globin mutation resulting in a reduced binding of 2,3-bisphosphoglycerate

Familial Erythrocytosis

Lysine --> Methionine base substitution

Decreased + charge of the binding side for 2,3-BPG increases hemoglobin oxygen affinity.

Resembles Hemoglobin F

47

Pt. with DKA, or underlying immunosuppression with facial and periorbital pain, headache, and purulent nasal discharge. Black eschar (necrotic tissue) may be seen on the palate or nasal turbinates.

Mucormycosis

Mucor, Rhizopus, Absidia species

Broad, nonseptate hyphae that branch at wide 90 degree angles

48

What is the acute phase reactant synthesized by the liver that acts as the central regulator of iron homeostasis?

Hepcidin

 

Low hepcidin levels increase intestinal iron absorption and stimulate iron release by macrophages.

49

Numbness and tingling in both legs and difficulty walking for several months. Tires more easily with physical activity. Mucosal pallor and loss of vibration and position sensation in the bilateral lower extremeties with associated gait ataxia. What is lacking?

Vitamin B12 deficiency

Only happens after complete absence for intake for 4-5 years.

Subacute combined degeneration of the spinal cord - from impaired myelin synthesis, specifically in the dorsal and lateral columns

50

What class of medication binds to PPAR-gamma and what effect do they have on insulin?

Thiazolidinedione (TZD) like pioglitazone

Decrease insulin resistance

51

How do you distinguish between acute stress disorder and PTSD?

PTSD = at least 1 month

Acute stress disorder = 3 days to 1 month

52

Tamoxifen can be used in males for what purpose?

Prevention and treatment of gynecomastia in patients on androgen deprivation therapy (for prostate cancer).

 

Selective estrogen receptor modulator

53

Patient who complains of difficulty with stairs and frequent falling secondary to "knee buckling". Patellar reflex diminished.

Femoral Nerve Neuropathy

Also will have weak quadricep muscle, and loss of sensation over the anterior and medial thigh and medial leg

54

After a transplant: diffuse maculopapular rash that has a predilection for palms and soles and may desquamate, diarrhea, intestinal bleeding, abdominal pain.

Approx a week after the transplant

Graft vs. Host Disease

Donor T cells against host MHC antigens

55

A vertical midline episiotomy will cut through what structure?

Perineal Body

56

What is the pathogenesis of type 2 diabetes?

Insulin resistance and relative insulin deficiency

Chronically elevated free fatty acid levels contribute to the insulin resistance by impairing insulin-dependent glucose uptake and increasing heptatic gluconeogenesis.

57

Symmetrical proximal muscle weakness, increasing difficulty climbing stairs, getting up from a chair, carrying heavy objects. Biopsy shows endomysial mononuclear inflammatory infiltrate and patchy muscle fiber necrosis.

Polymyositis

+ ANA, anti-jo-1, anti-histidyl-tRNA synthetase 

Elevated muscle enzymes (CK, aldolase)

Associated with interstitial lung disease, myocarditis

58

Thoracentesis is preformed in what 3 areas?

6-8th rib midclavicular

8-10th midaxillary

10-12th paravertebral

 

*If needle is inserted higher, there is a risk of lung injury

59

What is the most common cause of sudden cardiac death (abrupt cessation of organized cardiac activity with hemodynamic collapse, causing an inability to maintain adequate tissue perfusion) in the first 48 hours after acute MI?

Ventricular Fibrillation - due to electrical instability due to a lack of perfusion in the ischemic myocardium

60

What are P bodies?

Distinct foci foudn within eukaryotic cells that are invovled in mRNA regulation and turnover.

They play a fundamental role in translation repression and RNA decay, and contain numerous proteins including RNA exonucleases, mRNA decapping enzymes, and constituents incolced in mRNA quality control and microRNA-induced mRNA silencing.

They also function as a form of mRNA storage, as certain mRNAs are incorporated into P bodies to be later released and utilized for protein translation.

61

What drug is ideal for prevention of breast cancer AND osteoporosis without increasing the risk of endometrial cancer?

Raloxifene

Estrogen antagonistic activity on breast and uterus + estrogen agonist activity on bone (decreases bone resportion and improves bone mineral density)

62

Patients are encouraged to rinse out their mouth after using daily inhaled glucocorticoids for what reason?

Deposition of the medication in oral mucous membranes can lead to oral candidiasis.

63

Aortic regurgitation with mediastinal widening, suggesting an aortic aneurysm that has dilated the aortic annulus with a postitive serology for syphilis = what type of syphilis? 

Tertiary syphilis

Vasa vasorum endarteritis and obliteration, resulting in inflammation, ischemia, and weakening of the adventitia. Aneurysmal dilation of the thoracic aorta results and can extend to involve the aortic valve ring.

64

What explains the 2 most common complications of Crohn's disease: strictures and fistulas?

Transmural inflammation

65

Loud, blowing holosystolic murmur at the mid to lower left sternal border with no symptoms inititially = what congenital heart lesion? When can this be heard?

Ventricular Septal Defect (VSD)

*most common congenital heart lesion*

Will not be heard until 4-10 days after birth when pulmonary vascular resistance declines, enabling L-R shunting

66

What are the 4 characteristics of Ulcerative Colitis?

1. The rectum is always involved.

2. Inflammation is limited to mucosal and submucosa

3. Mucosal damage is continuous

4. Hallmark = bloody diarrhea, with or without pain

67

Liver disease with hepatomegaly, abdominal pain, skin hyperpigmentation (in sun-exposed areas), diabetes mellitus secondary to pancreatic islet destruction, impotence, arthropathy, and cardiac dysfunction/enlargement.

Hemochromatosis

AR

Abnormally high iron GI absorption

68

What are the 2 mechanisms for development of diabetic neuropathy?

1. Non-enzymatic glycosylation of proteins leading to increased thickness, hyalinization, and narrowing of the walls of arteries.

2. Intracellular hyperglycemia in peripheral nerves. Accumulating glucose is converted to sorbitol and fructose by aldose reductase. Sorbitol increases water influx into cell --> osmotic damage to axons and schwann cells.