Quick and Dirty Flashcards
Pancoast tumor
- Apex of lung tumor near SUPERIOR SULCUS - Non-small cell lung cancer (ie squamous or adeno) - Can compress and invade brachial plexus –> ipsilateral shoulder pain, upper limb paresthesias, & areflexic arm weakness - Involvement of cervical SYMPATHETIC ganglia –> Horner’s syndrome (partial ptosis, miosis, anhydrosis)
Ipsilateral shoulder pain upper limb paresthesia on ipsilateral side ptosis, miosis, anhydrosis on ipsilateral side
Pancoast tumor
On LM neurons w/ shrunken nuclei, no detectable nissl substance and intensely eosinophilic cytoplasm =?
IRREVERSIBLE cell injury –> red neuron (may also see pyknosis - condensation of chromatin)
Irreversible cell injury/Acute neuronal injury (red neuron)
-Shrunken nuclei - Loss of Nissl substance -Eosinophilic cytoplasm - Pyknosis of nucleus Visible 12-24 hours after injury
Axonal reaction due to loss of axon (type of response due to type of injury)
- Enlargement of the cell body - Eccentric nucleus (moves to periphery) - Enlargement of the nucleolus - Dispersion of the Nissl substance
tumor near the superior sulcus
pancoast tumor (non-small cell lung cancer)
how long does it take to deplete folate stores?
Months in a normal individual, weeks in an alcoholic
How long does it take to deplete cobalamin stores?
Years
Pancytopenia, impaired blood cell differentiation, and clonal expansion of mutated hematopoietic cells in bone marrow with elevated MCV?
Myelodysplasia (premalignant condition)
What are signs of myelodysplasia?
Myelodysplasia is a premalignant condition that manifests w/: - Pancytopenia - Impaired blood cell differentiation - Clonal expansion of mutated hematopoietic cells in the bone marrow - Elevated MCV
Peripheral blood smear w/ folate deficiency will show what?
- Macrocytosis (MCV > 100) - Ovalocytosis - Neutrophils w/ hypersegmented nuclei (>5)
Definition of sensitivity + formula
The probability of a diseased person testing positive [Of all the diseased, likelihood that this a TP] Sensitivity = TP/(TP+FN) (vertical on grid)
Definition of specificity + formula
The probability of a non-diseased person testing negative [Of all of the non-diseased, likelihood that this is TN] Specificity = TN/(TN+FP) (vertical on grid)
Definition of Positive predictive value + Formula
The probability that disease is present given a positive result [Of all the positives, the likelihood that this is a diseased (TP)] PPV = TP/(TP+FP) (horizontal on grid; effected by prevalence)
Definition of Negative Predictive value + formula
The probability that disease is absent given a negative result [Of all negatives, the likelihood that this is a non-diseased (TN)] NPV = TN/(TN+FN) (horizontal on grid; effected by prevalence)
Positive likelihood ratio definition + formula
Positive likelihood ratio = a ratio representing the likelihood of having the disease given a positive result LR+ = Sensitivity / (1 - Specificity)
Negative likelihood ratio definition + formula
A ratio representing the likelihood of having the disease given a negative result LR- = (1-Sensitivity) / Specificity
Are likelihood ratios affected by prevalence?
No
What does a likelihood ratio >1 or
Likelihood ratio >1 indicates that the respective test result is associated w/ the presence of the disease Likelihood Ratio
Low vitamin D levels causes what disease in children and what disease in adults?
- Rickets in children - Osteomalacia in adults
What are the levels of serum Ca, phosphorous, and PTH found in an osteomalacia patient w/ deficiency of Vit D?
- Serum Ca: low - Serum Phosphorous: low - Serum PTH: high (bc trying to fix low Ca levels –> inc bone resorption (–> osteomalacia) & inc. excretion of phosphorous)
Elevated PTH, hypERcalcemia, & hypOphosphatemia is found when?
Patients w/ primary hypERparathyroidism
Decreased serum PTH, decreased serum Ca, & inc. serum phosphorous?
HypOparathyroidism - can be caused by severe hypOmagnesemia which can be seen w/ prolonged diarrhea
HypOmagesemia esp w. prolonged diarrhea can cause what disease?
HypOparathyroidism (dec. serum PTH & Ca & inc. serum phosphorous)
What causes pseudohypoparathyroidism?
resistance to PTH (–> normal to low Ca, elevated phosphorous, elevated PTH)
Which ocular motor nerve (III, IV, VI) is most often affected by diabetes?
CNIII (oculomotor n.) - unilaterally
Symptoms of diabetic CN III mononeuropathy
- acute onset diplopia - down and out position of eye - ptosis
Acute onset diplopia, down and out gaze, ptosis in a diabetic, what disease is most likely and what is the most likely cause?
Diabetic CN III mononeuropathy caused by ischemic nerve damage, predominantly involving the core of the nerve and sparing the peripheral part
The somatic component of CN III is located where in the nerve?
Centrally
The autonomic component of CN III is located where and what is it responsible for?
Peripherally located Responsible for pupillary constriction & accomodation
CN III mononeuropathy due to ischemic nerve damage predominantly involve what portion of the nerve & what would remain intact?
- Predominantly involves the core of the CN III w/ relative sparing of the peripheral part - Pupillary size & reactivity is normal (b/c periphery where autonomic component is located is spared)
How can you tell the difference b/t CN III neuropathy due to ischemic nerve damage vs nerve compression?
Nerve compression damages periphery of nerve –> autonomic (parasympathetic) changes –> pupillary dysfunction (dilated pupil & loss of accomodation) Ischemic damage occurs in center of nerve –> motor changes w/ normal pupillary response –> acute onset diplopia, down and out gaze, ptosis
Causes of CN II nerve compression
- Transtentorial (uncal) herniation - Neoplasms - Aneurysms of posterior cerebral & posterior communicating arteries
Midbrain lesions cause bilateral or unilateral ptosis?
MIdbrain lesions cause bilateral ptosis because bother levator palpebrae are innervated by a single subnucleus
Movement disorder with behavioral abnormalities such as aggressiveness, apathy or depression & dementia
Huntington Disease
Triad of Huntington disease
- Chorea (movement disorder) - Behavioral abnormalities (aggressiveness, apathy, depression) - Dementia
Huntington disease has what kind of inheritance and penetrance?
Autosomal dominant w/ 100% penetrance (complete penetrance)
Which Huntington patients will will develop the disease earlier in life and why?
Huntington patients who receive the abnormal gene from their fathers b/c during spermatogenesis, CAG repeats rapidly increase while the number of trinucleotide repeats remains the same during maternal transmission.
Which diseases are commonly associated with anticipation?
Trinucleotide repeat disorders such as: - Huntington Disease - Fragile X Syndrome - Myotonic Dystrophy - Friedreich Ataxia
What is pleiotropy?
When one gene mutation leads to multiple phenotypic abnormalities. Is seen in Huntington’s b/c one gene mutation –> dysfunction in behavior, movement, and cognition
One gene mutation that leads to multiple phenotypic abnormalities
Pleiotropy
The presence of two populations of cells w/ different genotypes in one patient
Mosaicism Can be seen in Turner syndrome (46XX/45XO genotype), Klinefelter (46XY/47XXY) and Down Syndrome
Mosaicism is?
The presence of two populations of cells w/ different genotypes in 1 patient. Seen in Turner syndrome (46XX/45XO), Klinefelter (46XY/47XXY) and Down Syndrome
Jerky movements and happy disposition
Angelman syndrome, genomic imprinting –> inactivation of mother’s chromosome 15
Angelman syndrome
- Inactivation of mother’s chromosome 15 (Genetic imprinting) - Jerky movements & happy disposition (“happy puppet”)
Prader-Willi syndrome
- Inactivation of paternal chromosome 15 (genetic imprinting) - Insatiable hunger & thirst - Emotional lability (big swings)
Insatiably hungry & thirsty and emotionally unstable
Prader-Willi syndrome genomic imprinting –> inactivation of paternal chromosome 15
Granulosa-thea cell tumors are primarily identified in what population?
Postmenopausal women
Granulosa theca cell tumors are categorized as what type of tumor?
sex cord stromal tumors (derived from ovarian stroma)
The yellow coloration of an ovarian mass indicates what?
Lipid content and therefore hormonal activity
Granulosa-theca cell tumor’s composition is what?
Largely granulosa cells and a scattering of theca cells
A granulosa tumor is usually bilateral or unilateral?
Unilateral
Granulosa-theca cell tumors have what type of effect since they secrete what?
Feminizing effect b/c they secrete estrogen
Large amounts of estrogen release may cause what in prepubertal girls and in older women?
Girls – precocious sexual development Older women - fibrocystic change of the breast, endometrial hyperplasia, endometrial carcionma
Granulosa cells look like what histologically?
small, cuboidal cells that grow in cords or sheets.
What may be found in granulosa cell tumors that are small gland-like structures that contain acidophilic material?
Call-Exner bodies
Call-Exner bodies are found when and what do they look like?
- Found in Granulosa cell tumors - Small, gland-like structures tat contain an acidophilic material - Suggestive of immature follicles
How do thecomas present histiologically?
Cells present as clusters or sheets of cuboidal cells
Tumors consisting primarily of thecoma cells are generally benign or malignant?
Benign
What tumors can be ID’d by human chorionic gonadotropin?
Trophoblastic and other germ cell tumors including extra-gonadal tumors.
Germ cell tumors can be ID’d from what hormone?
Human chorionic gonadotropin
What produces alpha fetoprotein?
Fetal liver and yolk salk normally
Some cancers:
hepatocellular, nonseminomatous testicular or ovarian carcinomas
What is a tumor marker for nonseminomatous testicular carcinomas, ovarian, hepatocellular carcinoma?
Alpha-fetoprotein (AFP)
Is CA-125 used as a screening tool for ovarian cancer?
No it is not specific enough
It is best used as a way to monitor therapeutic response
What glycoprotein is best used to monitor therapeutic response of malignant ovarian cancers?
Cancer antigen 125 (CA-125)