PATHOLOGY: BOARDS AND BEYOND Flashcards
What is primary intention in wound healing?
Is a wound healing process where the wound edges are sutured together, leading to a more straightforward healing progression.
What are the initial events that occur in wound healing within the first 24 hours?
In the first 24 hours, clot formation occurs, and neutrophils invade the wound site to help prevent infection.
What is the role of macrophages in the wound healing process?
Macrophages replace neutrophils after about three days, aiding in debris phagocytosis and promoting healing by releasing growth factors.
What occurs in the wound during the proliferative phase?
During the proliferative phase, granulation tissue fills the wound space, angiogenesis occurs, and fibroblasts infiltrate, initiating collagen synthesis.
What is angiogenesis, and when does it occur in wound healing?
Angiogenesis is the formation of new blood vessels, occurring during the proliferative phase of wound healing, typically from about three days to one week post-injury.
How long does collagen remodeling continue after the initial wound healing?
Collagen remodeling can continue for up to six months to one year after the injury.
At one week post-surgery, what phase of healing is the girl’s wound in, and what is happening?
At one week post-surgery, the wound is in the fibroblast proliferative phase, where angiogenesis and collagen synthesis are actively occurring.
What is granulation tissue, and when does it fill the wound space?
Granulation tissue is a thick fluid composed of proteins and cells that fills the wound space from about three days to one week post-injury.
What key processes occur during the proliferative phase of wound healing?
During the proliferative phase, angiogenesis occurs, fibroblasts infiltrate the wound, and collagen synthesis begins.
What happens to inflammatory cells and fibroblasts after one month of healing?
After one month, inflammatory cells are absent, and only fibroblasts remain in the wound.
What changes occur in collagen during the remodeling phase?
During remodeling, changes include the cross-linking of collagen fibers to increase the strength and stability of the healed tissue.
What factors determine wound strength?
Wound strength depends on the amount and quality of collagen deposition.
What is the state of collagen in the first few days after an injury?
In the first few days after injury, no collagen is present, making wounds prone to failure.
What is used to maintain skin approximation in the early days after injury?
Sutures, staples, or other devices are used to maintain skin approximation during this period.
When does collagen deposition begin after an injury?
Collagen deposition begins around days 3 to 5 after the injury.
What type of collagen is initially deposited and what does it get replaced with over time?
Initially, type III collagen is deposited, which is then replaced with stronger type I collagen over time.
When is collagen synthesis considered complete after an injury?
Collagen synthesis is complete by several weeks after the injury.
What modifications occur to collagen in the later phases of wound healing?
In the later phases, modifications such as crosslinking occur, which further increase wound strength.
What is the composition of mature scars in terms of collagen?
In mature scars, type III collagen and fibronectin are no longer present, and all collagen is type I.
What is the role of vascular endothelial growth factor (VEGF) in wound healing?
VEGF is critical for angiogenesis, which occurs after about 3 days post-injury, facilitating the growth of new blood vessels that bring fibroblasts to the wound.
Why are fibroblasts important in the wound healing process?
Fibroblasts secrete collagen, which is essential for wound strength and integrity.
What is the critical process that occurs in the first 24 hours of wound healing?
Clot formation is critical for achieving hemostasis at the wound site.
What are the first cells to appear at the wound site after an incision?
The first cells to appear are platelets.
Platelets rapidly develop into clots to help stop bleeding and facilitate wound healing.
What type of wound healing occurs when there is no scar formation?
This occurs in tissues capable of regeneration, like the skin, if the basement membrane remains intact and basal layer stem cells are not destroyed.
Why do superficial skin wounds often heal without a scar?
Superficial skin wounds do not disrupt the basement membrane, allowing the skin to regenerate without scarring.
Which other tissues can heal with no scar formation?
Tissues such as the gastrointestinal mucosa after an ulcer and the lungs after pneumonia can also heal with no scar if they have regenerative capacity and the basement membrane and stem cells remain intact.
What processes are absent when tissues heal without scarring?
None of the typical scar processes will occur in tissues that heal without scarring.
What is delayed wound healing, and when might it be observed?
Delayed wound healing is a common problem in clinical medicine, characterized by minimal granulation tissue and potential dehiscence of the wound several days post-surgery.
What are some common causes of delayed wound healing?
Common causes include infection, diabetes, glucocorticoid therapy, and poor nutritional status.
In patients with autoimmune diseases, what therapy is likely to contribute to delayed wound healing?
Glucocorticoid therapy
How do glucocorticoids affect the wound healing process?
Glucocorticoids have anti-inflammatory effects, including the inhibition of neutrophil migration, which delays the wound healing process.
What does the X-ray of a lung abscess typically show?
A lung abscess appears as a black hole surrounded by white in the lung field on an X-ray.
What is a classic complication of Klebsiella pneumonia?
A lung abscess
What type of organism is Klebsiella pneumoniae?
A gram-negative rod.
In which patient population is Klebsiella pneumoniae infection most common?
In patients with impaired host defenses, particularly heavy alcohol users.
What type of necrosis is characteristic of tuberculosis infection?
Caseous necrosis
What pathological process leads to the formation of a lung abscess in Klebsiella pneumonia?
A lung abscess forms due to localized liquefactive necrosis within the lung tissue.
Involves blood vessels and occurs in vasculitis syndromes.
Fibrinoid necrosis
Is a subtype of coagulative necrosis seen with ischemia to limbs or the bowel.
Gangrenous necrosis
What characterizes coagulative necrosis?
Coagulative necrosis is characterized by the preservation of tissue architecture despite cell death, often seen in ischemic organ damage, such as myocardial infarction.
What is a typical finding in the heart during coagulative necrosis?
A typical finding is a firm, white area in the left ventricle consistent with an infarction, where the tissue remains intact.
What occurs during liquefactive necrosis?
Liquefactive necrosis occurs when proteolytic enzymes remain functional, leading to the destruction of large amounts of tissue, resulting in a liquid mass.
In which conditions is liquefactive necrosis commonly observed?
Liquefactive necrosis is commonly observed in abscesses and in the brain following a stroke.
What was the outcome in the second patient who experienced a stroke?
The second patient experienced tissue loss in the cortex due to liquefactive necrosis.
Is seen in pancreatitis when fatty acids bind calcium.
Fat saponification
What is coagulative necrosis?
Is a type of tissue death where proteolytic enzymes are destroyed, preserving the tissue architecture. It is commonly associated with ischemic organ damage, such as myocardial infarction.
What is a key finding in coagulative necrosis of the heart?
A key finding is a firm, white area in the left ventricle, indicative of an infarction, where the tissue remains intact and not liquefied.
What is liquefactive necrosis?
Liquefactive necrosis occurs when proteolytic enzymes remain functional, leading to the destruction of large amounts of tissue, resulting in a liquid mass.
In which scenarios is liquefactive necrosis commonly observed?
Liquefactive necrosis is commonly seen in abscess formation and in the brain following a stroke.
What happened to the brain tissue in the patient who had a stroke?
The patient who had a stroke experienced tissue loss in the cortex due to liquefactive necrosis.
Is seen in pancreatitis when fatty acids bind calcium.
Fat saponification
What is the most common cause of acute pancreatitis?
The most common cause of acute pancreatitis is gallstones obstructing the pancreatic duct flow, known as gallstone pancreatitis.
How do gallstones lead to acute pancreatitis?
Gallstones can enter the common bile duct and block the flow of pancreatic enzymes into the duodenum, causing accumulation of these enzymes within the pancreas.
What is the exception among pancreatic enzymes regarding their activation?
Most pancreatic enzymes are secreted as inactive zymogens; however, pancreatic lipase is secreted in its active form.
What role does pancreatic lipase play in acute pancreatitis?
Pancreatic lipase breaks down fat, triggers inflammation, and leads to fat necrosis, contributing to the pathology of acute pancreatitis.
What are the potential outcomes of acute pancreatitis?
Mild cases may involve acute inflammatory changes and mild fat necrosis, while severe cases can include vascular inflammatory injury and hemorrhage.
Where can fat necrosis occur in the context of acute pancreatitis?
Fat necrosis may occur within the pancreas and in the retroperitoneum, including the omentum, bowel mesentery, and subcutaneous fat.
What is the major cause of liver damage in acute hepatitis B infection?
The major cause of liver damage in acute hepatitis B is apoptosis of hepatocytes induced by CD8+ T cells.
How does the inflammatory infiltrate in acute viral hepatitis differ from that in bacterial infections?
Acute viral hepatitis shows a lymphocyte infiltrate in the liver, whereas bacterial infections typically present with acute inflammatory infiltrates containing neutrophils.
What kind of necrosis is observed in acute hepatitis B, and what does it signify?
Acute hepatitis B may exhibit “spotty necrosis,” but apoptosis is the primary process damaging liver cells.
What are the microscopic findings in a liver biopsy of a patient with acute hepatitis B?
A biopsy may show shrunken hepatocytes with intensely eosinophilic cytoplasm and fragmented nuclei, indicating apoptosis.
What type of immune cells are primarily involved in the liver damage seen in acute hepatitis B?
CD8+ T cells are primarily responsible for causing apoptosis of hepatocytes in acute hepatitis B.
What is polyarteritis nodosa (PAN)?
PAN is a vasculitis syndrome involving small to medium-sized blood vessels, characterized by systemic inflammation and various organ involvement.
What are the key clinical features of polyarteritis nodosa to remember for exams?
Key features include:
- Evidence of systemic inflammation (fever, elevated white blood cells, elevated ESR)
- Skin rash
- Neurologic symptoms (paresthesias, weakness)
- Renal failure
What type of skin lesions are commonly associated with polyarteritis nodosa?
Common skin findings in PAN include vesicles, nodules, and purpura.
What neurological symptoms are associated with polyarteritis nodosa?
Neurologic findings in PAN include focal (unilateral) neuropathies, such as paresthesias and weakness.
What is the underlying mechanism of polyarteritis nodosa?
PAN is an immune-complex-mediated disease, characterized as a type III hypersensitivity reaction, with immune complexes deposited in blood vessels.
What viral infection is strongly associated with polyarteritis nodosa?
Polyarteritis nodosa is strongly associated with hepatitis B infection, with about 30% of patients having chronic hepatitis B.
What are the histological findings characteristic of polyarteritis nodosa?
Histologic findings may include inflammatory cells in vessel walls, fibrinoid necrosis, and thrombus filling the lumen of small blood vessels.
How is polyarteritis nodosa diagnosed?
Diagnosis is made through biopsy of an affected site (such as the kidney, nerve, or GI tract) since there are no specific blood tests for this disorder.
What mediates inflammatory pain, such as that occurring after surgery?
Prostaglandin E2 and bradykinin.
What is a potential target for pain control drugs related to inflammatory pain?
Blockade of bradykinin could be a target for pain control drugs.
What is Icatibant, and for what condition is it used?
Icatibant is a bradykinin receptor antagonist used to treat hereditary angioedema to prevent vasodilation effects mediated by bradykinin.
Have bradykinin antagonists been successful in reducing pain?
Bradykinin antagonists have been tried for pain reduction but have not been successful, although research continues in this area.
What is the primary role of anti-histamine drugs in inflammation?
Anti-histamine drugs limit vasodilation and edema from inflammation but do not directly alleviate pain.
What role does lipoxygenase play in inflammation?
Lipoxygenase synthesizes eicosanoid signaling molecules, specifically leukotrienes.
What is the function of the cytokine IL-6 in inflammation?
IL-6 triggers the liver to synthesize acute-phase reactants.
How does angiotensin-converting enzyme (ACE) affect bradykinin levels?
ACE breaks down bradykinin; therefore, ACE inhibitors may raise bradykinin levels and can lead to angioedema.
Why are ACE inhibitors not as effective for pain control?
Since bradykinin mediates inflammatory pain and ACE inhibitors raise bradykinin levels, they are not as effective as pain control agents.
What is the role of the hypothalamus in the body’s response to infection?
The hypothalamus regulates body temperature, altering the temperature set point in response to pyrogens during infection.
What are the major cytokines involved in acute inflammation?
IL-1, TNF-alpha, and IL-6.
What are endogenous pyrogens?
Endogenous pyrogens are substances produced by the body, such as IL-1 and TNF-alpha, that lead to fever and other systemic responses during infection.
What mnemonic can help remember the major cytokines of acute inflammation?
The mnemonic “one-alpha-six” corresponds to IL-1, TNF-alpha, and IL-6.
How does fever develop in response to infection?
Cytokines like IL-1 and TNF-alpha circulate and increase production of prostaglandin E2 (PGE2) in the hypothalamus, which alters the temperature set point and causes fever.
What systemic responses can occur alongside fever during an infection?
Systemic responses include muscle wasting (cachexia), elevated white blood cell count, and hypotension.
What cytokines are primarily involved in chronic inflammation?
The primary cytokines involved in chronic inflammation are IFN-gamma and IL-12.
What mnemonic can help remember the cytokines of chronic inflammation?
The mnemonic “gamma-twelve” corresponds to IFN-gamma and IL-12.
What is C-reactive protein (CRP)?
CRP is an acute phase reactant that can activate the complement system but does not play a major role in generating fever.
How does CRP function in the context of inflammation?
CRP activates the complement system, aiding in the immune response during inflammation.
What characterizes a transudative pleural effusion?
A transudative pleural effusion has lower concentrations of total protein and LDH in the pleural fluid compared to serum.
How can Light’s criteria help differentiate between transudative and exudative effusions?
Light’s criteria indicate a transudative effusion if pleural fluid protein and LDH levels are significantly lower than serum levels.
What could be the underlying cause of transudative pleural effusions in an elderly patient?
In elderly patients, transudative pleural effusions are often due to diastolic heart failure or conditions like heart failure, which can complicate infections.
What is the mechanism by which left heart failure leads to transudative pleural effusion?
In left heart failure, pulmonary capillary hydrostatic pressure rises, driving fluid into the pleural space without changing vascular permeability.
What is the significance of performing a thoracentesis in patients with suspected pleural effusions?
Thoracentesis helps determine the nature of the pleural effusion (transudative vs. exudative) and identify potential causes, such as infection or heart failure.
What are the characteristics of an exudative pleural effusion caused by bacterial infection?
In an exudative pleural effusion, hydrostatic pressure is normal or low, and vascular permeability is increased, allowing protein and LDH levels in the pleural fluid to be elevated compared to serum.
What is pyelonephritis?
Pyelonephritis is a bacterial infection of the kidney that often begins as a urinary tract infection. It can cause symptoms such as dysuria, fever, chills, and elevated white blood cell count.
How does pyelonephritis typically develop?
Pyelonephritis typically develops when bacteria ascend from the urinary tract into the kidneys, leading to a systemic response to the infection.
What is a leukemoid reaction?
A leukemoid reaction is a physiologic response to infection characterized by a very high white blood cell count (WBC) with immature neutrophils (band forms) in the blood, often resembling leukemia.
What are common laboratory findings in pyelonephritis?
Common findings in pyelonephritis include elevated white blood cell count, particularly with immature neutrophils, and signs of infection such as dysuria and fever.
What distinguishes leukemia from pyelonephritis in terms of symptoms?
Leukemia often leads to markedly elevated white blood cell counts and may cause “B symptoms” (fever, chills) without focal infectious symptoms like dysuria, which are present in pyelonephritis.
What are the peripheral blood smear findings in acute leukemia?
Acute leukemia typically shows blasts in the peripheral smear.
What characterizes chronic myelogenous leukemia (CML) on a blood smear?
CML may show neutrophils and band forms, along with other myeloid cells such as eosinophils, basophils, myeloblasts, promyelocytes, or myelocytes.
How can the presence of bacteria in urine help differentiate between pyelonephritis and leukemia?
The presence of bacteria in the urine strongly supports the diagnosis of an infection (like pyelonephritis), making it more likely than a hematologic malignancy like leukemia.
What are the main myeloproliferative disorders?
Chronic Myelogenous Leukemia (CML)
Polycythemia Vera
Essential Thrombocytosis
Myelofibrosis
Which myeloproliferative disorder is characterized by increased white blood cell counts and the presence of band forms?
Chronic Myelogenous Leukemia (CML) is characterized by increased white blood cell counts and the presence of band forms.
Do polycythemia vera, essential thrombocytosis, or myelofibrosis typically present with increased white blood cell counts and band forms?
No, polycythemia vera, essential thrombocytosis, and myelofibrosis do not typically present with increased white blood cell counts and band forms as seen in CML.
Lymphoma is a malignancy of lymphocytes. Lymphoma generally presents as
A mass (“-oma” indicates mass), often of lymph nodes.
What is acute diverticulitis?
Acute diverticulitis is an inflammatory process occurring in a diverticulum of the colon.
Name some acute-phase reactants whose levels increase during inflammation.
Ferritin
Fibrinogen
Serum amyloid A
C-reactive protein (CRP)
Hepcidin
What is a negative acute-phase reactant, and how does it respond to inflammation?
Albumin is a negative acute-phase reactant; its level decreases in response to acute inflammation.
What is the purpose of a positron emission tomography (PET) scan?
A PET scan detects radiation emissions from radiolabeled glucose to identify areas of possible malignancy in the body.
What is 18-fluoro-2-deoxyglucose (FDG)?
FDG is a radiolabeled form of glucose commonly used in PET scans to track glucose metabolism in tissues.
How do malignant cells, like those in squamous cell carcinoma, metabolize glucose?
Malignant cells metabolize glucose via aerobic glycolysis, preferentially converting it into lactate rather than pyruvate for the TCA cycle, even in the presence of oxygen.
What is the Warburg effect?
The Warburg effect describes the phenomenon where cancer cells preferentially use glycolysis to metabolize glucose to lactate, resulting in less ATP production per glucose molecule and excess lactic acid production.
Why do cancer cells require more glucose than normal cells?
Cancer cells require more glucose to meet their higher ATP needs due to their reliance on glycolysis, which is less efficient than oxidative phosphorylation.
What adaptations do cancer cells have to increase glucose uptake?
Cancer cells have more glucose transporters on their surface and increased levels of hexokinase to trap glucose inside the cell.
How can PET scans help distinguish between benign and malignant lung lesions?
Benign lesions typically do not take up excess glucose, while malignant lesions do, allowing PET scans to identify potential malignancies.
What is the function of telomerase in cells?
Telomerase stabilizes the ends of chromosomes, allowing replicating cells to divide indefinitely and become immortal.
In what percentage of breast carcinomas is telomerase found?
Telomerase is found in over 90% of breast carcinomas.
Where is telomerase normally active?
Telomerase is typically active in fetal cells and germ cells, with little to no activity in somatic cells, such as breast tissue.
Why is the presence of telomerase significant in cancer biology?
The presence of telomerase in cancer cells allows them to bypass normal cellular aging processes, leading to uncontrolled cell division and tumor growth
What percentage of invasive breast carcinomas express hormone receptors such as the progesterone receptor or the estrogen receptor?
About 75 to 80% of invasive breast carcinomas are positive for either the progesterone receptor or the estrogen receptor.
Why is the expression of hormone receptors significant in breast cancer?
The expression of hormone receptors (progesterone and estrogen) can influence treatment options, as hormone receptor-positive cancers may respond to hormonal therapies.
What are the two primary hormone receptors commonly expressed in breast cancer?
The two primary hormone receptors are the progesterone receptor (PR) and the estrogen receptor (ER).
What is the clinical relevance of testing for hormone receptors in breast cancer patients?
Testing for hormone receptors helps determine the most effective treatment plan, including the use of hormonal therapies such as tamoxifen or aromatase inhibitors for receptor-positive tumors.
Familial cases of breast cancer related to the BRCA1 and BRCA2 proteins are responsible for only about ? of cases of invasive breast carcinoma.
10%
What does tumor stage refer to?
Tumor stage refers to the degree of metastasis and spread of malignancy.
How is tumor stage determined?
CT scans, MRI, or PET scans.
What does tumor grade indicate?
Tumor grade indicates the differentiation of tumor cells and how aggressive the tumor is based on pathologic examination.
How is tumor grade determined?
Tumor grade is determined by pathologic examination of biopsy specimens
What is the main difference between tumor stage and tumor grade?
Tumor stage assesses the extent of spread and metastasis, while tumor grade assesses the aggressiveness and differentiation of tumor cells.
What is flow cytometry used for?
Flow cytometry is used to detect cellular fluorescence and analyze the characteristics of cells.
How are cells prepared for flow cytometry?
Cells are exposed to fluorescent antibodies that bind to specific surface markers.
What does fluorescence indicate in flow cytometry?
Fluorescence indicates that the cells express the surface antigen of interest.
What type of markers can flow cytometry detect?
Proteins associated with specific cell types, activation states, or diseases.
What is one application of flow cytometry in clinical practice?
Flow cytometry is commonly used in immunophenotyping for diagnosing hematological malignancies.
Is a lab technique used to detect DNA
Southern blotting
A frozen section
is a biopsy specimen that is quickly frozen after surgical removal of tissue. These can be rapidly reviewed by a pathologist to make quick decisions during an operation (e.g., whether the margins of a tumor have been entirely excised). In contrast, “permanent sections” are biopsy specimens placed in a fixative (usually formalin) for several hours. These are used when time is less critical.
What is a hallmark of malignant neoplasms related to immune evasion?
The ability to evade cell death by the immune system, specifically avoiding destruction by natural killer (NK) cells.
How do malignant cells respond to growth inhibitors?
Malignant cells demonstrate a weak response to growth inhibitors.
What is essential for the invasion and metastasis of malignant cells?
Malignant cells must invade basement membranes to spread beyond their local tissue beds.
What role does the p53 protein play in the cell cycle?
p53 arrests cell growth unless specific conditions are met, acting as the “guardian of the cell cycle.”
What happens in many malignancies regarding p53 function?
Many malignancies are associated with a lack of p53 function, leading to uncontrolled cell growth.
What is Li-Fraumeni syndrome?
A hereditary condition where patients have an abnormal p53 gene in all cells, leading to an increased risk of multiple malignancies.
What is a pulmonary hamartoma?
A benign lesion responsible for about 10% of pulmonary nodules; the most common benign tumor of the lung.
What types of tissue are typically found in a lung hamartoma?
isorganized but normal tissue including fat, epithelial cells, fibrous tissue, and cartilage.
How does calcification assist in identifying pulmonary hamartomas?
Calcification may be present, which helps with identification on x-ray or CT scan.
What is the growth rate and prognosis of pulmonary hamartomas?
They grow slowly over years and carry an excellent prognosis, classifying them as benign.
Malignant lung tumors may spread throughout the lungs and metastasize to the ? but not hamartomas.
Liver
May occur in small cell lung cancer, a malignant lung tumor.
Cushing’s syndrome and SIADH
How do glucocorticoids induce apoptosis in lymphocytes?
By activating caspase enzymes.
What is one therapeutic use of glucocorticoids in relation to malignancies?
They can induce apoptosis in malignant cells, including some leukemias.
What effect do glucocorticoids have as anti-inflammatory drugs?
They induce apoptosis in lymphocytes, reducing inflammation.
In the context of leukemia, what challenge can arise with glucocorticoid treatment?
Leukemic cells may become resistant to the pro-apoptotic effects of glucocorticoids.
Glucocorticoids are lipid-soluble steroid drugs that bind to ? not cell surface receptors.
Intracellular receptors,
Is the mechanism of some anti-cancer drugs including alkylating agents, but not glucocorticoids
DNA crosslinking
Induces apoptosis via the extrinsic pathway. This is used by CD8 T-cells to kill viral-infected cells.
FAS-FAS ligand binding
Is the result of cellular free radical damage.
Membrane lipid peroxidation
