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Flashcards in 5/20 Mixed Deck (33):

Lactase deficiency

Inherited autosomal recessive disorder, progressive non-persistence of lactase expression in adulthood, or inflammatory disorders affecting the intestinal brush border
Undigested lactose causes osmotic diarrhea and acidification (decreased stool pH) of the stool


Dx Trichomonas vaginalis

Saline microscopy (wet mount) of the discharge is the best diagnostic test


Poison ivy dermatitis

Form of allergic contact dermatitis
Type IV hypersensitivity reaction mediated primarily by T lymphocytes
Manifests as intensely pruritic erythematous papules, vesicles, bullae that often for linear patterns


Maternal rubella

Low grade fever, maculopapular rash, posterior auricular lymphadenopathy
Polyarthritis, polyarthralgia


Acute gouty arthritis

NSAIDS are the first line treatment for acute gouty arthritis
Inhibit cyclooxygenase and therefore decrease prostaglandin synthesis and exert a broad anti-inflammatory effect that includes inhibition of neutrophils


Statins + Macrolides (erythromycin)

Most statins are metabolized by cytochrome P-450 3A4, with the exception of pravastatin.
Concomitant administration of drugs that inhibit statin metabolism (e.g. macrolide) is associated with increased incidence of statin-induced myopathy and rhabdomyolysis.
Acute renal failure is a possible sequela of rhabdomyolysis


Methotrexate and 5-FU

Both effectively inhibit thymidylate formation, but the chemotherapeutic effect of methotrexate is overcome by N5-formyl-tetrahydrofolate (folinic acid, leucovorin) supplementation


Congenital adrenal hyperplasia

21 hydroxylase deficiency (progesterone > 11-deoxycorticosterone)
Affected female infants present at birth with ambiguous (virilized) genitalia)
Male infants have normal genitalia and present later with salt-wasting or precocious puberty
High serum levels of 17-hydroxyprogesterone is diagnostic


Severe combined immune deficiency

Combined T and B cell dysfunction
Life-threatening condition
Severe bacterial and viral infections, mucocutaneous candidiasis, persistent diarrhea, failure to thrive
Absent T cells and hypogammaglobulinemia
Thymic shadow is not usually present due to T cell deficiency



Lipopeptide antibiotic
Activity limited to gram-positive organisms including MRSA
It causes depolarization of bacterial cellular membrane and inhibition of DNA, RNA, and protein synthesis
Daptomycin is associated with increased creatine phophokinase levels and an increased incidence of myopathy



Second line agent for treating acute gouty arthritis
Inhibits tubulin polymerization and microtubule formation in leukocytes, reducing neutrophil chemotaxis and emigration to sites inflamed by tissue deposition of monosodium urate crystals
GI mucosal function is also impaired by microtubule disruption, leading to diarrhea, nausea, vomiting, abd pain


Filtration fraction

Fraction of plasma flowing through the glomeruli that is filtered across the glomerular capillaries into Bowman's space (FF= GFR/RPF).
Renal plasma flow can be determined from renal blood flow by multiplying the renal blood flow by (1-Hematocrit)


Human placental lactogen (hPL)

Decreases maternal fatty acid stores and increases maternal serum glucose in order to provide adequate glucose to the growing fetus
The actions of hPL result in physiologic insulin resistance in the latter half half of pregnancy
Gestational diabetes occurs when insulin secretion in inadequate


Interscalene nerve block

Anesthetizes the brachial plexus as it passes through the scalene triangle
It is used to provide anesthesia for the shoulder and upper arm
Nearly all patients develop transient ipsilateral diaphragmatic paralysis due to involvement of the phrenic nerve roots as they pass through the interscalene sheath


Lymphatic drainage of the rectum

Proximal to the anal dentate line occurs via the inferior mesenteric and internal iliac lymph nodes
Areas distal to the dentate line drain primarily into the inguinal nodes


General sensation from the anterior 2/3 of the tongue

Carried by the mandibular division of the trigeminal nerve
Gustatory innervation of the anterior 2/3 of the tongue is provided by the chorda tympani branch of the facial nerve


Small intestinal bacterial overgrowth (SIBO)

Can be caused by gastric bypass surgery
Due to excessive bacterial proliferation in the blind-ended gastroduodenal segment
Results in deficiency of most vitamins (B12, A, D, and E) and iron but increased production of folic acid and vitamin K


Unilateral fetal hydronephrosis

MC cause is narrowing/kinking of the proximal ureter at the ureteropelvic junction
Inadequate canalization of the ureteropelvic junction


Psoas abscess

Can occur as result of hematogenous or lymphatic seeding from a distant site or by spread from an adjacent site
Patients can present with fever, back or flank pain, inguinal mass, and difficulty walking
Inflammation of the psoas muscle causes pain when the hip is extended (psoas sign)


Extended-spectrum beta-lactamases

Can be produced by gram-negative bacteria
Rendering cephalosporins and other beta-lactam antibiotics inactive
These genes can be transmitted between organisms through plasmid conjugation



Low plasma sodium and osmolality
Inappropriately concentrated urine and clinically normal body fluid volume
Important cause is paraneoplastic effect secondary to small cell carcinoma of the lung


Rx Bacterial vaginosis

Clindamycin or metronidazole


Highly lethal fulminant hepatitis due to inhaled anesthetics

Cannot be distinguished histologically from acute viral hepatitis
Significantly elevated aminotransferase levels due to massive hepatocellular injury and a prolonged prothrombin time due to failure of hepatic synthetic function


Saddle anesthesia and loss of anocutaneous reflex

Symptoms of cauda equina syndrome
Damage to S2 through S4 nerve roots


Visceral obesity

Measures by waist circumference or waist-to-hip ratio
An important predictor of insulin resistance


Left ventricular free wall rupture

Usually occurs within 5-14 days after initial MI


Complications of chronic kidney dx

Renal osteodystrophy from secondary hyperparathyroidism (caused by hyperphosphatemia and hypocalcemia)


Prolonged exposure to loud noises causes high frequency hearing loss due to

Damage to the stereociliated hair cells of the organ of corti


Meckel diverticulum

Results from failed obliteration of the vitelline (omphalomesenteric) duct and usually presents with spontaneous but painless lower GI bleeding
99mTc-pertechnetate localizes ectopic gastric mucosa, and its increased uptake in the periumbilical/right lower quadrant is diagnostic for Meckel diverticulum


Gemfibrozil (and other fibrates)

Can reduce cholesterol solubility and promote gallstone formation by reducing bile acid synthesis
Caution should be used when prescribing fibrate therapy to patients with underlying gallbladder disease


Hirschsprung Disease Dx

Submucosal (Meissner) and myenteric (Auerbach) autonomic plexi are absent in the affected segment of bowel
The submucosa of the narrowed area is the most superficial layer where the absence of ganglion cells can be seen


Nitric Oxide

Synthesized from ARGININE by nitric oxide synthase
As a precursor of nitric oxide, arginine supplementation may play an adjunct role in the treatment of conditions that improve with vasodilation, such as stable angina



Most common benign lung tumors
Present as asymptomatic peripherally located "coin lesion" in patients 50-60 years old
These tumors are composed of disorganized cartilage, fibrous and adipose tissue