Pathology Flashcards
What is the most common site of obstruction causing fetal hydronephrosis?
Ureteropelvic junction
What lab finding/histological finding is pathognomonic for Babesiosis?
Giems-stained thin blood smear:
ring-shaped and “maltese cross-shaped” intraerythrocytic inclusions.
(the inclusions are the parasites themselves).
_____ and lyme are often co-infected because they are both transmitted by the _______ tick.
Babesiosis
Ixodes “deer” tick
*It’s also mostly located in New England a la Lyme. CT and RI are major locations.
“Currant jelly stools” =?
Intussusception (often secondary to Meckel’s diverticulum
What is Meckel’s diverticulum? How does it present?
An ileal outgrowth that results from failed obliteration of the vitelline (omphalomesenteric) duct.
Ectopic gastric mucosa secrete acid (via parietal cells) which ulcerates in RLQ
Presents with spontaneous but painless GI bleeding.
What STIs cause increased risk of ectopic pregnancy?
Chlamydia and gonorrhea due to tubal scarring and damage to fallopian tubes/PID.
What lesion causes a “pie in the sky”
A lesion in Meyer’s loop
What is Leukocyte Adhesion Deficiency?
An autosomal recessive disorder characterized by absence of CD18 antigens which are necessary for the formation of integrins. Integrins are needed for leukocyte adhesion to endothelial surfaces and migration to peripheral tissues.
Characterized by recurrent skin and mucosal infections and periodontal disease. Lack of purulence, impaired wound healing, late separation of the umbilical cord, and persistent leukocytosis.
What does a positive Direct Coombs test in a test for and mean?
Maternal antibodies (IgG) bind to fetal RBCs and cause destruction.
Happens in an Rh- mother when she has a SECOND Rh+ fetus
How much of the respiratory tract is ciliated?
From trachea to respiratory bronchioles (everything except alveolar ducts and alveoli)
If you see a baby eating honey, think…
botulism. Remember babies can eat SPORES in honey. Adults only can be infected by the toxin itself (such as in canned foods)
Where in the GI tract will you find Brunner glands on histology?
Duodenum ONLY
These guys are submucosal
What histological findings accompany celiac?
Villous atrophy and crypt hyperplasia
What type of mutation is unlikely to meaningfully change the size of mature mRNA?
Interestingly, nonsense mutations often don’t affect mature mRNA size very much because the differences at that point are small.
What is adenomyosis and how does it present?
Presence of endometrial glandular tissue within the myometrium.
Relatively common in middle-aged parous women
Heavy menstrual bleeding
Dysmenhorrhea
Diffusely/uniformly enlarged uterus
What is the common mutation among essential thrombocytosis, polycythemia vera, and primary myelofibrosis?
JAK2
This is a NONRECEPTOR, CYTOPLASMIC tyrosine kinase that causes constitutive tyrosine phosphorylation
Leukocytosis with marked left shift = ?
CML
left shift = myelocytes, metamyelocytes, band forms.
Philadelphia chromosome: t(9:22) BCR-ABL fusion protein
What are characteristic findings of primary myelofibrosis?
Severe fatigue, splenomegaly, hepatomegaly, anemia, and bone marrow fibrosis.
Initially bone marrow is hypercellular but eventually fibroses causing pancytopenia. Liver and spleen enlarge to compensate with extramedullary hematopoiesis. Peripheral smear characteristically shows teardrop-shaped RBCs (dacrocytes) and nucleated RBCs.
What kind of drug is ruxolitinib? What is it used for?
JAK2 inhibitor
used for primary myelofibrosis (and other myelproliferative diseases?)
What are the components of Thayer-Martin medium?
Vancomycin (inhib gram pos)
Colistin (inhib gram neg other than neisseria)
Nystatin (inhib yeast)
Trimethoprim (inhib gram neg other than neisseria)
Used to identify pathogenic neisseria organisms
What do Homeobox genes code for and what is their role in development?
Homeoboxes are highly conserved 180 nucleotide DNA sequences coding for TRANSCRIPTION FACTORS which ultimately lead to correct positioning and patterning in development.
Defects often result in skeletal malformations and improperly positioned limbs and appendages.
What pathogen causes subacute bacterial endocarditis (SBE) AND is associated with colonic cancer in ~25% of cases?
Strep gallolyticus (formerly S. bovis)
Often affects patients with preexisting valvular abnormalities
Infectious mononucleosis preferentially infects ______ by binding ____. In response, ______ clonally expand in an effort to destroy the virally-infected cells.
B Cells by binding CD21
CD8+ T cells clonally expand
Excessive raw egg white consumption can cause a deficiency in _______, thus affecting _______ enzymes.
Biotin
Carboxylase
(e.g. pyruvate carboxylase converting pyruvate to OAA)
What is Potter Sequence and what are the consequences for the fetus?
In fetus:
Urinary tract anomaly (renal agenesis is the classic example) -> anuria/oliguria in utero -> oligohydramnios:
- Pulmonary hypoplasia
- Flat facies
- Lower limb deformities
Esophageal or duodenal atresia leads to _____hydramnios.
Polyhydramnios
What is “holiday heart syndrome”?
Excessive consumption of alcohol can often trigger A-fib
The ______ portion of the duodenum can get trapped/pinched by the SMA.
Transverse
How does Measles present clinically?
Fever, cough, congestion, conjunctivitis, maculopapular rash.
The classic exanthema starts on the face and spreads in a cephalocaudal and centrifugal pattern. Erythematous, blanching, maculopapular lesions progress to deep red or brown, nonblanchin coalesced rash.
Acute measles depletes Vitamin ____ stores.
A
Tx with Vitamin A prevents and treats ocular complications, and reduces other comborbitdities, recovery time, and length of hospital stay.
What is another name for DiGeorge syndrome? And how does this indicate how it presents clinically?
DiGeorge Syndrome = Velocardiofacial syndrome
Clinical presentation (CATCH): Conotruncal cardiac defects (Tet, truncus arteriosus, interrupted aortic arch) Abnormal facies (bifid uvula) Thymic hypoplasia/aplasia -> T cell deficiencies Craniofacial deformities (cleft palate) Hypocalcemia/Hypoparathyroidism
What is the mutation associated with DiGeorge (Velocardiofacial) syndrome?
How is it detected?
Chromosome 22q11.2 microdeletion
Detected using FISH
What’s the most common cause of death from a VENTRICULAR aneurysm?
Heart failure - ejection fraction decreases substantially!
In general, right heart sounds are heard better upon _______.
Inspiration
In general, left heart sounds are heard better upon ________.
Expiration
What is an acute hemolytic transfusion reaction?
Type III antibody-mediated hypersensitivity within minutes to hours of starting a blood transfusion. Mediated by IgM Abs lead to complement activation of the MAC complex (C5b-C9) and cell lysis.
Presents with fever and chills, hypotension, dyspnea, chest and back pain, and hemoglobinuria.
DIC and renal failure may result.
Dental caries = ______ infection which = possible bacterial ________.
Dental caries = strep viridans infection which is also a common cause of bacterial endocarditis.
What are 2 classic symptoms/exam tip offs of PSGN?
Cola colored urine
Facial edema or puffiness
A humoral response to influenza involves antibodies directed against ________.
Hemagglutinin
Hepatitis D requires Hepatitis ____ for infection.
B
And thus Hep-B vaccinated people are immune to D as well.
Can children be infected with Hep A and not ever know it?
Yes, anicteric viral infection can present in childhood as vomiting and malaise without detectable liver dysfunction
How does Corynebacterium diphtheriae acquire pathogenicity to cause severe pseudomembranous pharyngitis?
Phage conversion/lysogenization permitting exotoxin AB production (Tox gene).
______ and ___-deficient patients are at higher risk of being infected with encapsulated species.
Spleen and C3
common encapsulated species = Strep pneumo, H flu, N. meningitidis
Why are asplenic patients at higher risk for infection?
Failure in systemic bacterial clearance because as bacteria get stuck in the red pulp cords of the spleen the macrophages that line the cords and sinusoids ingest them and present the antigens to B and T cells for a systemic immune response.
The cortisol, aldosterone, progesterone, thyroid hormone, retinoic acid, and Vitamin D all have receptors that bind directly to _____.
DNA
Incomplete fusion of the septump primum and septum secundum results in _______.
Patent foramen ovale (PFO)
How do Koplik’s spots appear? What are they pathognomnic for?
Appear as blue white spots on a red background esp on the buccal mucosa
Koplik’s spots = Measles!
70% of the population has “right dominant” cardiac circulation meaning _______. 20% are “left dominant” meaning _______. 10% are codominant.
Right dominant indicates that the right coronary artery supplies the posterior descending/interventricular artery.
Left dominant indicates that the left coronary artery feeds the PDA.
The PDA also contains the AV nodal branch.
What parts of the pancreas do the dorsal and ventral buds give rise to? What pathology occurs when they fail to fuse?
Dorsal pancreatic bud gives rise to the tail, the body, most of the head, and the accessory pancreatic duct (Santorini).
The smaller ventral bud gives rise to the uncinate process (a portion of the head), and the proximal portion of the main pancreatic duct (Wirsung)
Pancreas divisum occurs when they fail to fuse and the pancreatic secretions are then drained separately.
HLA Class I proteins include ___ (letter). How are they expressed?
Class I = HLA B type
They are expressed on all nucleated cells and present endogenous antigens to CD8+ cytotoxic T cells.
HLA Class II proteins include ____ (letter). How are they expressed?
DR, DP, DQ. They are expressed on antigen-presenting cells (e.g. macrophages, dendritic cells) and present predominantly foreign antigens to CD4+ helper T cells.
____________ is the most common cause of osteomyelitis in children with sickle cell disease.
Salmonella
If they say you have a baby with a “staccato” cough, think ________.
Neonatal pneumonia
Often due to being born to a mother with chlamydia
What is bilious emesis indicative of?
Obstruction below the second part of the duodenum.
Differential:
Midgut volvulus
What Hep B antigen is most indicative of infectivity and transmissibility to a fetus?
HBeAg
Syphilis lesions: Primary = ? Secondary = ? Latent = ? Tertiary = ?
Primary = Chancre -painless ulceration raised indurated borders - Secondary = Condyloma Lata - large grey wart-like growths. Diffuse macular rash (palms and soles) Tertiary = Gumma - benign painless indurated granulomatous lesions that progress to white-grey rubbery lesions that may ulcerate. Most commonly cutaneous
What is Chronic Granulomatous Disease (CGD)?
A condition caused by NADPH oxidase deficiency
Which immune cells help to form granulomas in TB and why?
Macrophages and CD 4+ T cells
Where does Parvovirus B19 replicate?
Erythrocyte precursor cells in the bone marrow
Hereditary Spherocytosis appearance, inheritance, associated disease.
Defect in spectrin calls normal to small round RBCs with decreased central pallor -> anemia and splenomegaly
HS is the ONLY disease that will cause an elevated MCHC
Autosomal dominant
Associated with cholelithiasis
Mnemonic for the “classic” encapsulated organisms (i.e. organisms that asplenic/sickle cell patients are at risk for):
SHiN
S. pneumo
What renal complication is associated with sickle cell?
Renal papillary necrosis due to decreased pO2 in papila and microhematuria causing infarcts.
How does HbC appear on blood smear?
Crystals inside RBCs
Target cells
(remember glu -> lyCine)
“-stigmine” is the suffix for what drug type? What are they used for?
Acetylcholinesterase inhibitors
Used to treat myasthenia gravis, nightshade poisoning, reverse inhibition of parasympathetic system
Polyarteritis Nodosa is associated with Hepatitis ___.
B
Polyarteritis Nodosa is a _____-vessel vasculitides caused by a Type ___ hypersensitivity reaction.
It mostly affects ____ and ____ vessels causing microanerusyms.
PAN = medium-vessel vasculitis Type III (immune complex) reaction
Mostly affects renal and visceral vessels causing renal microaneurysms.
Presents in middle aged men. 30% of the time associated with Hep B.
Headache, jaw claudication, and vision changes in an elderly person = ?
Giant (temporal) cell arteritis
Patients may also describe pain in the temporal artery region
Younger Asian female with absent or weak upper extremity pulses = ?
Takayasu’s large vessel arteritis causing pathological narrowing of large vessels
Strawberry tongue = ?
Kawasaki’s disease
How does polyarteritis nodosa appear on histology?
Tons of cell infiltrates
SEGMENTAL and TRANSMURAL necrosis
______ is the only childhood disease for which aspirin is used as treatment.
Kawasaki Disease
Thromboangiitis obliterans aka Buerger disease is seen exclusively in young people who do what?
Smoke EXCESSIVELY
Unsurprisingly this vasculitis causes thrombosis that obliterates the vessel (i.e. distal ischemia)
If you hear epiglottitis in kids think _____.
H. influenza
What is bacterial transformation?
Competent bacteria are able to pick up and important short pieces of naked external bacterial chromosomal DNA for incorporation into their genome.
Use of a DNase in the medium will destroy this naked external DNA and help identify if it is the source of newly acquired genes.
Dilated cardiomyopathy + cirrhosis + hyperpigmentation = ?
Where else might you find deposits?
Hereditary hemochromatosis - iron overload
In the liver as hemosiderin
Degenerative joint disease
Bronzed skin comes from iron upregulating melanin production NOT direct depositing of iron
Diabetes malabsorption
Steatorrhea
Possible to get restrictive cardiomyopathy instead of dilated
Secondary hypogonadism
What is mutation and inheritance of hereditary hemochromatosis? What HLA type?
Autosomal recessive - missense mutation in HFE gene on short arm of chromosome 6
HLA-A3
Upregulation of iron absorption in the gut and upregulated transferrin = ?
Hereditary Hemochromatosis
Medullary thyroid cancer is associated with MEN ___. It is cancer of the ________ cells.
MEN 2
Parafollicular C cells
What mnemonic is used to summarize structures arising from neural crest cells?
MOTEL PASS:
Melanocytes Odontoblasts Tracheal cartilage Enterochromaffin cells Laryngeal cartilage
Parafollicular cells of the thyroid
Adrenal medulla
Schwann cells (and all ganglia)
Spiral membrane
What causes paraneoplastic cerebellar degeneration?
Anti-yo anti-P/Q, and anti-Hu antibodies cause cross-reaction with Purkinje neuron antigens resulting in progressive dizziness, ataxia, dysarthria, and visual disturbances.
Most commonly results from small cell lung cancer, and occasionally breast, ovarian, and uterine cancer
Platelet aggregation is mediated by vWF binding to ______ receptors on the platelet membrane. vWF also mediates platelet adhesion to subendothelial collagen. Subsequently, vWF serves as a carrier for factor ____, prolonging its half-life.
GpIb
VIII
tl;dr vWF bridges platelets to subendothelial collagen
What is Gerstmann Syndrome?
Defect affecting the angular gyrus of the dominant parietal lobe (supplied by the MCA). The angular gyrus is part of the parietal association cortex, an area that integrates multisensory (eg visual, tactile, and verbal) information to comprehend events and solve problems.
Insults here lead to problems with agraphia (inability to write), acalculia (math), finger agnosia, and left-right disorientation.
Nitroglycerin is a ____dilator.
Venodilator
When given it causes venodilation and blood to collect/pool in the venous system, reducing cardiac workload.
What is Hirschprung Disease?
Neural crest cells in the gut arrest their migration during development leaving a segment of the colon deprived of ganglion cells (anything distal also will lack ganglions). This causes narrowing of the segment because it cannot relax and thus proximal portions dilate.
“crutch palsy or saturday night palsy” = compression of what nerve?
Radial
Causing weakness in forearm, hang, and finger extensor muscles.
PCP is an NMDA receptor _______ist.
Antagonist
ST segment elevation in leads II, III, aVF = block of ?
RCA
ST segment elevation in leads V5 and V6 +/- I and and aVL = block of ?
LCX
Where does transthyretin (TTTR gene) amyloidosis deposit its amyloid?
Heart
The Anterior Pituitary is derived from surface _____ and is aka ________.
Surface ectoderm
Rathke’s pouch
Generally speaking, neuroectoderm = __NS and neural crest = __NS
Neuroectoderm = CNS
Neural crest = PNS
The Posterior Pituitary is derived from _____ and is aka ________.
neuroectoderm
Neurohypophysis
Of the FLAT PiG hormones, which are basophils and which are acidophils?
FLAT = basophils PiG = acidophils
What mnemonic is used to remember which cell types make the hormones of the posterior pituitary?
VSOP (a type of cognac)
VS = Vasopressin, Supraoptic nucleus OP = Oxytocin, Paraventricular
What enzyme heterozygosity/deficiency causes gestational diabetes and mature onset diabetes of the young? Why?
Glucokinase
Glucokinase phosphorylates glucose once it enters the liver. Multiple rounds of glycolysis in response to increased blood glucose generate sufficient ATP that is recognized by the liver and causes insulin release.
