Block 13

Question 1

Nipple discharge
Physiologic
Pathologic

Answer 1

• Physiologic ( billateral, nobloody, milky without masses or skins changes)
• pathologic (bloody or serosanguineous and unilateral with/without palpable masses and skin changes)

Question 2

Intraductal papillomma

Answer 2

• MCC of alarming bloody seosanguineous nipple discharge.
• affected patients have no associated breast mass or skin changes.
• intraductal papilloma is caused by proliferation of papillary cells in a duct or cyst wall with fibrovascular core
• it may contain foci of atypia or DCIS.

Question 3

alpha 1 antytrypsin

Answer 3

• inhibits several proteolytic enzymes (neutrophil elastase)
  -AATD–> panacinar emphysyma
  -AATD –> neonatal hepatitis is common ,
  In adults –> hepatomegaly, cholestasis, elevated transaminases , and milf thrombocytopenia.

Question 4

HS purpura(HSP)
Complications

Answer 4

-disease usually preceeded by viral or STREP, URI.
- Ag from infection –> simulate IgA production –>IgA immune complex deposition on vessel wall –> inflammation.
Complications:
1. GI: intermmitent sever abdominal pain, hematemesis and bloody diarrhea, bowel wall edema and increased risk for intussusception
2. Kidney: renal involvment in HSP is identical to that seen in berger disease. Both cause mesangial proliferation and and crescent formation.
3. HSP classically causes palpable purpura on the buttocks and lower extremities. These lesions may begin as urticatrial papules or plaques and subsequently evolve into purpura.
4. Joints: migratory arthlagias and arthritis are most commonly seen in large joints of the lower extremities possible because of their dependent nature.

Question 5

Kawasaki disease

Answer 5

• swollen lymph nodes
• high fevers, strawberry tongue
• perioral erythema and fissuring
• periungual desquamation.

Question 6

Second branchial cleft persistance

Answer 6

• normally obliterated in utero

- persistance leads to branchial cleft Cyst between the angle of the mandible and sternocleidomastoid muscke.

Question 7

What vascular beds are most susceptible for athersclerosis

Answer 7

Lower abdominal aorta and coronary arteries

Question 8

Persistant fever, sore throat, anterior and posterior cervical lymphadenopathy , and splenomegaly

Answer 8

EBV

Question 9

EBV infections, immune response

Answer 9

• after infection the virus gains access to the blood stream where it perferentially infects B- lymphocytes by binding to the CD21 cell surface receptor.
• CD8+ clonally exoand in response to EBV infected B cells in an effort to destroy virally infected cells.

Question 10

Folate deficiency leads to anemia –> ?

Answer 10

Due to diminshed thymidine synthesis.

• folic acid is a single carbon donor required for synthesis of purine and pyramidine (eg.thymidine) bases incorporated in DNA.
• RNA and protein synthesis may continue relatively unaltered, leading to a state of unbalanced cytoplasmic growth with impaired cell division.

Question 11

Fibrates mechanism of action (fenofibrate, gemfibrozil)

Answer 11

• upregulation of LPL
• increased oxidation of FA
• inhibit cholesterol 7a- hydroxylase, which catalyzes the rate limiting step in the synthesis of bile acids.
• the reduced bile acid production results in decreased cholesterol solubility in bile and favors the formation of cholesterol stones.

Question 12

Aromatase effect on Gallbladder

Answer 12

• estrogens increase biosynthesis of cholesterol by up-regulating hepatic HMG-CoA.
• HRT, OC increases the amount of cholesterol secreted in bile and contribute to formation of gallstones.
• its inhibition will lead to decrease in gallstone formation.

Question 13

African americana, female , pulmonary infiltrates , and hilar adenopathy.
- immune response

Answer 13

Sarcoidosis

- the immune response is Th1 –> IL-2 –> IFN-¥

Question 14

CO effect on blood parameters

Answer 14

• CO bind to hemoglobin with an affinity of approximately 250 times of that of O2
• reducing the number of heme binding sites for O2 –> levels of CO- bound hemoglobin (carboxyhemoglobin) increases.
• when hemoglobin available in plasma decrease –> CO decreases the oxygen carrying capacity –> and oxygen content of blood
• however not the amount of oxygen dissolved in the plasma (PaO2)
• it causes left shift in hemoglobin dissociation curve reflecting a decreased tendency of O2 to unload to tissues.

Question 15

Mutations in the env gene in HIV leads to

Answer 15

-evasion of humoral immune response

Question 16

Mutation in pol gene in HIV

Answer 16

• drug resistance is associated with prolonged use of HAART, a regimen that includes inhibitors of HIV RT and protease.
• pol gene mutation are responsible for the mergence of HIV protease variant that are resistant to standard protease inhibitors.
• its also responsible for structural changes in HIV RT that render the enzyme resistant to standard nucleoside and non-nucleoside RT inhibitors.

Question 17

High altitude changes

Answer 17

• the partial pressure of inspired air falls at high altitudes. The result in hypoxemia with marked reduction in arterial O2.
• tissue hypoxia triggers chemoreceptors in the carotid bodies to stimulate ventilation.,
• hyperventilation leads to fall in PaCO2 –> respiratory alkalosis and PH rises acutely.
• renal compensation leads to —> decreased HCO3-
• result after 24-48 hours of hypoxia is hypoxemia –> with complete or partial compensated respiratory alkalosis.

Question 18

Compensatory physiological changes that contribute to long term high altitude acclimatization include

Answer 18

• increase 2,3 DPG
• increased hemoglobin production
• increased pulmonary diffusion capacity
• vascular endothelial growth factor induced angiogenesis
• increase in cellular mitochondria count
• hemoconcentration due to HCO3 diuresis and fluid shift.

Question 19

Anovulatory cycles

Answer 19

In most women menustral cycles are consistent and last 24-35 days with menustual flow ranging from 4-6 days

• however adolescents typically have immature HPO axis for several years following menarche.
• during this time they may have longer menustrual cycles and irregular bleeding patterns due to the presence of anovulatory cycles.
• in the absence of ovulation, the ovarian follicule doesnt degenerate and become a corpus luteum.
• no progesterone is produced as a result and E2 levels remains high.
• causing endometrium to remain in proliferative phase.
• proliferative endometrium becomes disorganized and fragile with unstable cenous capillaries resulting in stromal breakdown with variable, but often heavy bleeding.

Question 20

Musculocutaneous nerve injury

Answer 20

• most commonly in the setting of a trauma (shoulder dislocation) and stenous upper extremity activity (basebul pitching) .
• the nerve is derived from C5-C7, arises from the lateral cord of brachial plexus.
• innervates major forearm flexors (biceps brachii, brachialis and coracobrachialis
• the remaining fivers become the lateral cutaneous nerve of the forearm and provide sensory innervation to the skin of the lateral forearm.

Question 21

Medial forearm sensory innervation

Answer 21

Branch of the medial cord of brachial plexus -> medial cutaneous nerve of the forearm.

Question 22

Hypersegmented neutrophils

Answer 22

Megaloblastosis

Question 23

Imperforate hymen

Answer 23

(Hematoclopos in pic)

• an imporforate hymen is an obstructive lesion caused by incomplete degeneration of the central potion of the fibrous tissue band connecting the walls of the vagina. At birth, vaginal secretions stimulated by the motehrs estrogen can cause mucocopos (accumulation of mucus in the vaginal canal of fetus).
• this may manifest as bulging introitus, if the condition remains undiagnosed, the mucus is reabsorbed and the child will be assymptomatic until menarche.
• pts present with primary amneorrhea, normal secondary sexual characterestics with cyclic abdominal or pelvic pain.(due to accumulation of menustrual blood in the vagina and uterus)(hematoclpos)
• result is collection of blood can also cause back pain and difficulties with defecation.
• secondary sexual development is normal as the patient has no chromosomal or hormonal abnormalities.

Question 24

Oral thrush, interstitial pneumonia and severe lymphopenia during the first years of life

Answer 24

-consistent with mother to child vertical transmission of HIV-1.
-the risk of transmission to patients who haven’t received ART therapy is as high as 35%
-ART during pregnancy reduces risk of prenatal transmission to 1-2%.
-all pregnant women with HIV positive should take ART.
-2 nucleoside/neucleotide RT inhibtors, along with third drug (protease,integrase ,no-nceulceoside RTinhibtors)’
-

Question 25

Infant born to HIV mother receives which drug for prophylasxis

Answer 25

Zidovudine

Question 26

IFN-a used in treatment of

Answer 26

- HEP B - kaposi sarcoma - hairy cell leukemia - condyloma acuminata

Question 27

E>coli virulance factors

Answer 27

1. LPS: --> bacteremia and septic shock 2. K1 capsular polysaccharide --> neonatal meningitis 3. Verotoxin --> Gastroenteritis (bloody) 4. HS/HL exotoxin --> gastroenteritis (watery) 5. P fimbriae --> UTI

Question 28

Organisms that ferment lactose

Answer 28

E.coli, klibsiella and enterobacter

Question 29

Excessive bleeding with CKD

Answer 29

- its due to accumulation of uremic toxins - the toxins impairs platelets aggregation and adhesion resulting in qulitative platelet disorder charactrized by increased BT. - PT, PTT, PC all normal - it can be fixed with dialysis

Question 30

Retroperitoneal fluid collection anterior to psaos muscle -->

Answer 30

- retroperitoneal hematoma (isodense fluid), can arise secondary to warfarin use. - the risk of bleeding in patients with warfarin and patients with high risk factors such as increased age, D.m, hypertension and alcoholism is high. - femoral neuropathy can result --> weakness involving quadriceps muscle group, and may have weakining of ilipsaos. - difficulty with stairs and frequent falling secondary to knee buckling. - patellar reflex is diminished.-sensory loss over the antetrior and medial thigh and medial leg is typical. - acute, severe pain in the groin., lower abdomen and back,

Question 31

Femoral nerve course

Answer 31

Descends through the fibers of psaos major muscle, emerges laterally between psaos and iliacus muscle and then runs beneath the inguinal ligament into the thigh. -femoral nerve mono-neurotherapy can occur due to trauma,(pelvic fracture ), hematoma,(warfarin use) abscess or strech

Question 32

Congenital rubella

Answer 32

1. Sensorineural deafness 2. Cataracts 3. Cardiac malformation (PDA) 4. Microcephaly 5. Eye abnormalities. 6. Intelectuall disability

Question 33

vWD disease

Answer 33

- menorrhagia - epistaxis - Iron deficiency anemia due to recurrent bleeding - (bleedining from skin, mucosal sites, nasal mucosa, GI tract, and endometrium).

Question 34

VWf binds to , functions

Answer 34

- exposed collagen - it promotes platelet adhesion at the site (Gp1b) - it promotes platelet aggregation (GpIIb/IIIa) - carrier protein for factor VIII

Question 35

Prostacyclin

Answer 35

Inhibtor of platelet aggregation and a vasodilator.

Question 36

Metacholine is used for

Answer 36

Diagnosis of asthma if a patient comes with history of asthma but has normal spirometry values. (Bronchoprovocation tecnhiques).

Question 37

Flutamide mechanism

Answer 37

-inhibit androgen receptor interaction (testosterone to act with its receptor)

Question 38

Ionizing radiation effect on DNA

Answer 38

- theraputic ionizing radiation used to treat several types of cancer. Through 2 major mechanisms 1. DNA double strand breakage: breakage of 2 strandes usually required as one straind is repaired with olymerases 2. Free radical formation: Reactive O2 species are formed by ionization of water, O2 free radicals are then able to cause cellular and DNA damage.

Question 39

Bacteroieds, treatment

Answer 39

-gram begative anerobic rod that can produce ß lactamase, enzyme that can break up penicillin. - beta-lactamase inhibtors such as tazobactam, cluvanic acid and sulbactam can prevent these enzymes from functioning. Treated mainly with piperacillin -tazobactam Other like metranidazole,carbapenems and clindamycin.

Question 40

Emphysyma spirometry

Answer 40

- increased TLC - decreased FEV1/FVC - decreased CO diffusing capacity (destruction of alveoli and capillary beds)

Question 41

Difference in neurotransmitter in sympathetic and parasympathetic system

Answer 41

1. Parasymphathetic : preganglionic neurons --> secrete actylcholine --> bind to postganglionic neurons --> release actylcholine --> activating muscarinic receptors within target organs 2. Symphathetic: preganglionic neurons --> release actylcholine -> bind to postganglionic neurons--> relaese NE, activating alpha or beta receptor.

Question 42

Exceptions in sympathetic and parasympathetic systems

Answer 42

1. Chromaffin cells of the adrenal medulla release NE and EP directly into the circulation after stimulation by actylcholine released from preganglionic neurons 2. Preganglionic and postganglionic sympathetic neurons in sweat glands are cholinergic.

Question 43

MRSA treatment

Answer 43

1. Line is vancomycin( if allergic) 2. Daptomycin 3. Linezolid 4. Tigecycline 5. Ceftaroline

Question 44

Daptomycin mechanism, indication and side effects

Answer 44

Indicated for MRSA that can be treated with vancomycin Mechanism : depolarizes cellular membrane by creating transmembrane channels. (Intracellular ion leakage) N.B== it binds and inactivated by pulmonary surfactant, hence ineffective in pneumonia. AE: 1. Myopathy and creatinie kinase elevation. 2. Inactivation of pulmonary surfactant

Question 45

Right sided endocarditis involving tricuspid valve

Answer 45

S.aureus, usually MRSA

Question 46

Inezolid | Indication AE and mechanism

Answer 46

Mechanism: inhibits bacterial protein synthesis by binding to bacterial 23S ribosomal RNA of the 50S subunit. -used in MRSA AE: optic neuritis, serotonin syndrome especially if used with proserotonergic drugs.

Question 47

Gallstones mechanism in pregnancy

Answer 47

-estrogen induced cholesterol hyper-secretion and progesterone induced gall bladder hypo-motility

Question 48

``` Clavicle muscles insertions or origins Inferolateral Inferomedial Superolateral Superomedial ```

Answer 48

1. Inferolateral: deltoid and subclavian muscles 2. Inferomedial : pectoralis major and sternohyoid 3. Supramedial: SCM 4. Suprealeteral : trapezius

Question 49

``` Spherocytosis Inhertience Clinical Treatment Lab findings ```

Answer 49

-AD inheritence Clinically: 1. Hemolytic anemia 2. Jaundice 3. Splenomegaly Diagnosis is done using infusion of glycerol hypotonic solution and checking if the hemoglobin goes out (hemolysis) Complications : pigmented gall stones, aplastic crisis from B19 infection Treatment : splenectomy Lab findings: 1. Increased MCHC, 2. Spherocytes on blood smear 3. Negative coombs test

Question 50

TATA box mutation (cnsensus sequence ) leads to

Answer 50

Transcription initiation defect

Question 51

RET protoncogene mutation are

Answer 51

Present in more than 95% in patients with medullary thyroid carcinoma

Question 52

Medication that causes hyperkalemia

Answer 52

1. Non selective ß blockers 2. ACEI 3. ARBS 4. K+ sparing diuretics 5. Digoxin 6. NSAID