5/18 Mixed

Question 1

Lingual thyroid

Answer 1

Thyroid gland is formed from evagination of the pharyngeal epithelium and descends to the lower neck
Due to failure of migration, the thyroid can reside anywhere along the thyroglossal duct’s usual path, including the tongue
Normal thyroid follicles containing colloid
Dysphagia, dysphonia, dyspnea

Question 2

Acute hemolytic transfusion reaction

Answer 2

Antibody mediated (type II) hypersensitivity reaction caused by pre-existing anti-ABO antibodies that binds antigens on transfused donor erythrocytes
Subsequent complement activation results in erythrocyte lysis, vasodilation, symptoms of shock
Fever, hypotension, chest and back pain, hemoglobinuria (red-to brown colored urine)

Question 3

Rheumatoid arthritis

Answer 3

Autoimmune disease triggered by an unknown antigen
Cartilage components serve as autoantigens that activate CD4 T cells, which in turn stimulate B cells to secrete rheumatoid factor, an IgM antibody specific for the Fc component of self IgG

Question 4

Paroxysmal nocturnal hemoglobinuria

Answer 4

Gene defect that leads to uncontrolled complement-mediated hemolysis
Class triad: hemolytic anemia, hemoglobinuria, pancytopenia, thrombosis at atypical sites
Chronic hemolysis can cause iron deposition in the kidney (hemosiderosis)

Question 5

Bicuspid aortic valve

Answer 5

Common cause of aortic stenosis in US
Harsh crescendo-decrescendo systolic ejection murmur heard best in the right second intercostal space with radiation to the carotids

Question 6

Gap junctions and labor contractions

Answer 6

Gap junctions facilitate communication and coordination between cells and play an important role in labor contractions
Connexins are proteins that assemble into gap junctions and their density increases in the uterus before delivery in response to rising estrogen levels

Question 7

SPECIFIC Ab for rheumatoid arthritis

Answer 7

Antibodies to citrullinated peptides/proteins have a high specificity for RA

Question 8

Why is the Hepatitis C virus genetically unstable

Answer 8

Because it lacks proofreading 3’ to 5’ exonuclease activity in its RNA polymerase
Its enveloped glycoprotein sequences also contain a hypervariable region prone to frequent genetic mutation

Question 9

Communicating hydrocele

Answer 9

Serous fluid accumulates within the tunica vaginalis in the setting of a patent processus vaginalis
Presents as a painless swelling that transilluminates on examination

Question 10

Acute effects of corticosteroids

Answer 10

Increased neutrophil count
Decreased lymphocyte, monocyte, basophil, eosinophil count
Increase in the neutrophil count results form “demargination” of neutrophils previously attached to tehv vessel wall

Question 11

Cardiac catheterization

Answer 11

Optimal site for obtaining vascular access in the lower extremity is the common femoral artery below the inguinal ligament
Cannulation above the inguinal ligament can significantly increase the risk of retroperitoneal hemorrhage

Question 12

Celiac disease

Answer 12

Immune-mediated reaction to gluten, can present with bloating, diarrhea, flatulence as well as short stature and weight loss
Screening tests show an elevated level of IgA against tissue transglutaminase
Duodenal biopsy is confirmatory showing villus flattening and intraepithelial lymphocyte infiltration

Question 13

Methadone

Answer 13

Drug of choice for maintenance treatment of opioid abuse
Potent, long-acting opioid agonist with good bioavailability and can be given in once-daily oral dosing
Its prolonged effects suppress withdrawal symptoms and cravings, allowing for more productive patient functioning

Question 14

Hep B and Hepatocellular carcinoma

Answer 14

Hepatitis B virus integrates its DNA into host genome, thereby increasing the risk for hepatocellular carcinoma.
In contrast, hepatitis C virus (an RNA virus), lacks reverse transcriptase and does not integrate into the host genome

Question 15

Polyene antifungals

Answer 15

Amphotericin B, Nystatin

Act by binding ergosterol in the fungal cell membrane

Question 16

N-myc

Answer 16

Transcription factor, capable of binding DNA

Therefore, can be detected by DNA probes

Question 17

Superficial lympathic system in the lower extremities

Answer 17

Divided into medial and lateral tracks
The medial track runs up to the superficial inguinal lymph nodes, bypassing the popliteal nodes
Lesions on the medial foot cause inguinal lymphadenopathy whereas lateral lesions are more likely to cause lymphadenopathy in both the popliteal and inguinal areas

Question 18

Schizoaffective disorder

Answer 18

Psychosis must occur in the absence of major mood episodes (depression or MANIA), but mood symptoms must be present for most of the illness.
In major depressive or bipolar disorder with psychotic features, psychotic symptoms occur exclusively during mood episodes

Question 19

Beta-thalassemia

Answer 19

Caused by mutations that result in defective transcription, processing, and translation of beta-globin mRNA
Leads to deficiency of the beta-globin chains required for normal hemoglobin synthesis

Question 20

Pityriasis versicolor (tinea versicolor)

Answer 20

Hypopigmented, hyperpigmented, or erythematous macules or patches on the upper body
Malassezia species yeasts, infection confined to the stratum corneum
Forms spores and hyphae, producing the characteristic “spaghetti and meatballs” appearance on KOH preparation light microscopy

Question 21

Primary mineralocorticoid excess (hyperaldosteronism)

Answer 21

Causes increased renal sodium reabsorption, leading to hypertension, hypokalemia, and metabolic alkalosis (normal sodium, low K, high bicarb)

Question 22

Pseudomonas aeruginosa

Answer 22

Non-lactose fermenting, oxidase-positive, MOTILE, gram negative rod
Most common cause of malignant otitis externa, a serious infection of the ear seen in elderly diabetic patients
Exquisite ear pain and drainage, and granulation tissue is often seen within the ear canal

Question 23

Digestion of dietary lipids (triglycerides, phospholipids, cholesterol esters)

Answer 23

Primarily digested in the duodenum via pancreatic enzymes
Bile salts emulsify lipid breakdown products, forming water soluble micelles that facilitate lipid absorption in the jejunum
Most cholecystectomy patients can tolerate fatty foods in the diet as bile is constantly being release into the duodenum

Question 24

Use dependence

Answer 24

A phenomenon in which higher rates of depolarization lead to increased sodium channel blockade due to the channels spending less time in the resting state
For class 1 atniarrhythmics, sodium channel binding strength is 1C>1A>1B.
Class 1 C antiarrhythmics demonstrate the most use dependence and class 1B (lidocaine) have the least

Question 25

Myotonic dystropy

Answer 25

AD, caused by an increased number of trinucleotide repeats on myotonia-protein kinase gene
Sustained muscle contaction (myotonia) along with weakness and atrophy is common
Cataracts are seen in almost all patients
Frontal balding and gonadal atrophy are other common features

Question 26

Primase

Answer 26

A DNA-dependent RNA polymerase that incorporates short RNA primers into replicating DNA
(when uracil would be found in association with bacterial DNA–uracil is only found in RNA)

Question 27

Kaposi’s sarcoma

Answer 27

Usually involves the skin and GI tract and is common in HIV patients not on antiretroviral therapy
Endoscopy reveals characteristic lesions, which range form reddish/violet flat maculopapular lesions to raised hemorrhagic nodules or polypoid masses
Biopsy can show spindle cells, neovascularization, and extravasated red blood cells

Question 28

Defense against Candida

Answer 28

Local defense against Candida is performed by T cells, whereas systemic infection is prevented by neutrophils
For this reason, localized candidiasis is common in patients who have HIV, but neutropenic individuals are more liely to have the systemic form of the disease

Question 29

Granulomatosis with polyangiitis (Wegener’s)

Answer 29

Cause of rapidly progressive (crescentic) glomerulonephritis (RPGN) type 3 (pauci-immune)
Symptoms of nephritis are accompanied by signs of upper and lower respiratory tract involvement
Crescents on light microscopy, the absence of deposits on immunofluorescence, elevated serum c-ANCA are diagnostic

Question 30

Familial dysbetalipoproteinemia (type III hyperlipoproteinemia)

Answer 30

AR disorder characterized by elevated cholesterol and triglycerides
Caused by defects in ApoE3 and ApoE4, leading to decreased clearance of chylomicrons and VLDL remnants
Patients can develop eruptive and palmar xanthomas and premature atherosclerosis

Question 31

Disruptions in female reproductive development

Answer 31

Paramesonephric ducts fuse to form the fallopian tubes, uterus, cervix, and upper vagina. Disruptions of this process can lead to a variety of mullerian tract anomalies and real anomalies are a common comorbidity.
Incomplete lateral fusion of the paramesonephric ducts results in bicornuate uterus characterized by an indentation in the center of the fundus

Question 32

Friedreich ataxia

Answer 32

AR, presents during childhood/adolescence
Progressive gait ataxia, impaired joint and vibration sense
Hypertrophic cardiomyopathy
Skeletal abnormalities (kyphoscoliosis, pes cavus), diabetes mellitus
Complications from cardiomyopathy are the most common cause of death

Question 33

Aromatase deficiency

Answer 33

Aromatase converts androgens into estrogens in the ovaries, testes, placenta, peripheral tissues
Placental aromatase deficiency causes accumulation of androgens during pregnancy, resulting in ambiguous external genitalia in female infants and matenral virilization

Question 34

Norepinephrine

Answer 34

Stimulates cardiac B1 adrenoreceptors, which utilize the cAMP signal transduction pathway
Stimulation of these receptors by NE causes increases in cAMP concentration within cardiac myocytes

Question 35

Chediak-Higashi syndrome

Answer 35

AR disorder of neutrophil phagosome lysosome fusion that results in neurologic abnormalities (nystagmus), partial albinism, and an immunodeficiency caused by defective neutrophil function

Question 36

Paranoid personality disorder

Answer 36

Lifelong pattern of pervasive suspicion and distrust

Do not have fixed delusions and other psychotic symptoms

Question 37

Superficial inguinal lymph nodes

Answer 37

Drains all skin from the umbilicus down, including the anus (below the dentate/pectinate line) but excluding the testes, glans penis, and posterior calf

Question 38

Permissiveness

Answer 38

Occurs when one hormone allows another to exert its maximal effect
Cortisol exerts a permissive effect on many hormones to help improve the response to a variety of stressors
Cortisol increases vascular and bronchial smooth muscle reactivity to catecholamines and increases glucose release by the liver in response to glucagon

Question 39

Placement of a suprapubic cystostomy

Answer 39

Bladder is EXTRAPERITONEAL
In placement of the suprapubic cystostomy, the trocar and cannula will pierce the layers of the abdominal wall but will NOT enter the peritoneum