Brs Environmental Pathology

Front 1

What is an abrasion or scrape?

Back 1

Superficial tearing away of epidermal cells.

Front 2

What is a laceration?

Back 2

A jagged tear, often with stretching of the underlying tissue.

Front 3

What is an incision?

Back 3

A clean cut by a sharp object.

Front 4

What is a puncture?

Back 4

A deep tubular wound produced by a sharp, thin object.

Front 5

What is a contusion?

Back 5

A bruise caused by disruption of underlying small blood vessels; commonly involves the skin but may also involve internal organs

Front 6

Name five causes of death due to mechanical injury.

Back 6

1) Hemorrhage into body cavities
2) Fat embolism from bone fractures
3) Ruptured viscera
4) Secondary infection
5) Renal shutdown caused by acute tubular necrosis, especially when associated with myoglobin casts arising from crush injury of skeletal muscle.

Front 7

What is brain damage due to blunt force injury?

Back 7

With possible skull fracture; can be the direct result of cerebral trauma or caused by intracranial hemorrhage.

Front 8

What is brain laceration due to blunt force injury?

Back 8

Caused by fracture with penetrating injury by skull fragments.

Front 9

What is a brain contusion due to blunt force injury?

Back 9

May occur at the point of impact (coup) or on the opposite side of teh brain (contracoup).

Front 10

What conditions may result from abdominal injury?

Back 10

1) Contusion
2) Rupture of teh spleen or liver, sometimes wiht severe hemorrhage
3) Rupture of the intestine, which can result in peritonitis.

Front 11

What conditions may result from thoracic injury?

Back 11

1) Rib fracture, possibly with penetration into pulmonary parenchyma or thoracic wall vessels.
2) Hemothorax, or hemorrhage in the pleural cavity.
3) Pneumothorax, or air in the pleural cavity.

Front 12

What are knife or stab wounds?

Back 12

1) Can be incisions or puncture wounds
2) Result in highly variable consequences, depending on the site of the injury.

Front 13

Describe gunshot wounds.

Back 13

1) Entrance wound is usually smaller and rounder than the exit wound (and in some cases even smaller than the bulet because the skin is elastic)
2) Exit wounds may be significantly larger than the bullet due to tumbling of the bullet (and tissue and bone fragments accompanying the bullet) and are usually irregular or stellate rather than round.
3) In contact wounds, there may be burning around the margins of the wound (abrasion ring)
4) Contact wounds over teh skull and other areas with skin closely overlying bone may demonstrate a stellate (star-shaped) appearance due to gases from the gun undermining the skin margins.
5) Close-range wounds (20 inches or less) demonstrate unburned powder particles in teh skin (tattooing or stippling) and deposits of soot on the skin.
6) Long-range wounds are usually round or oval, demonstrating clean margins without evidence of stippling or fouling.

Front 14

What is a first-degree burn?

Back 14

Partial thickness burns
Characterized by hyperemia without significant epidermal damage; they generally heal without intervention.

Front 15

What is a second-degree burn?

Back 15

Partial thickness burns
Characterized by blistering and destruction of teh epidermis with slight damage to the underlying dermis; they generally heal without intervention.

Front 16

What are third-degree burns?

Back 16

Full-thickness burns
Characterized by damage to the epidermis, dermis, and dermal appendages; skin and underlying tissue are often charred and blackened; these burns often require skin grafting.

Front 17

What are complications of burns?

Back 17

1) Inhalation of smoke or toxic fumes, resulting in pulmonary or systemic damage
2) Hypovolemia, which results from fluid and electrolyte loss
3) Curling ulcer (acute gastric ulcer associated with severe burns)
4) Infection; most common cause of late fatalities; most frequent organism is P. aeruginosa.

Front 18

What happens during freezing?

Back 18

1) May be generalized, resulting in death.
2) May be localized, resulting in frostbite; usually affects exposed areas such as fingers, toes, earlobes, or nose.
3) Severe, prolonged frostbite may result in intracellular ice crystals, intravascular thrombosis, and sometimes local gangrene.

Front 19

What is electrical injury?

Back 19

1) Occurs when electrical current passes through an individual, thus completing an electric circuit. Fatal electrical injury is usually caued by current passing through the brain or heart
2) May cause respiratory or cardiac arrest or cardiac arrhythmias.
3) May result in small cutaneous burns with blister formation at the point of entry or exit of the electric current. At times, burns may be severe.

Front 20

What is a UV light injury?

Back 20

1) causes sunburn, which is caracterized by erythema, often with superficial desquamation and, in severe cases, blister formation.
2) Associated with premalignant cutaneous lesions (actinic keratosis) and malignant cutaneous lesions such as squamous and basal cell carcinomas and melanoma.

Front 21

What is Ionizing radiation?

Back 21

1) From x-ray, radioactive waste, nuclear disaster, and other exposure.
2) Damages cells by forming toxic free radicals, affecting vital cell components such as DNA adn intracellular membranes.

Front 22

What happens in localized radiation?

Back 22

1) Skin changes such as dermatitis, ulceration, and skin malignancies
2) Pulmonary changes, including acute changes simmilar to those of adult respiratory distress syndrome; and chronic changes, such as septal fibrosis, bronchiolar metaplasia, and hyaline thickening of blood vessel walls
3) GI inflammation and ulceration
4) Hematopoietic alterations, including bone marrow depression or leukemia.
5) Neoplasia; myeloid (but not lymphoid) leukemias; cancers of bone, skin, thyroid, lung, or breast

Front 23

What happens in severe and generalized radiation?

Back 23

1) Occurs in whole body irradiation such as that seen in nuclear disasters.
2) Severe central nervous system (CNS) injury primarily caused by capillary damage
3) GI mucosal denudation
4) Acute bone marrow failure

Front 24

Describe radiosensitivity of specialized cells?

Back 24

1) Lymphocytes; the earliest blood cells to be affected
2) Most sensitive cells: lymphoid, hematopoietic, germ, gastrointestinal mucosal, rapidly dividing tumor

Front 25

Describe alcohol abuse?

Back 25

1) An important cause of death and disability from several causes ranging from automobile accidents to homicides.
2) Characterized by a constellation of changes that are collectively grouped as chronic alcoholism.

Front 26

What are the common pathologic findings of alcohol abuse?

Back 26

1) Alcohoic hepatitis and cirrhosis
2) Acute and chronic pancreatitis
3) Gastritis
4) Oral, pharyngeal, laryngeal, esophageal, and gastric carcinoma
5) Alcoholic (dilated) cardiomyopathy
6) Aspiration pneumonia
7) Myopathy
8) Peripheral neuropathy
9) Cerebral dysfunction
10) Fetal alcohol syndrome; microcephaly, mental retardation, facial and cardiac defects.

Front 27

Describe the cerebral dysfunction related to alcohol abuse.

Back 27

1) Caused by a combination of alcoholism adn thiamine deficiency.
2) Often associated with hemorrhagic necrosis of mamillary bodies.
3) Wernicke syndrome is a combinatoin of ataxia, confusion, opthalmoplegia, and often nystagmus.
4) Korsakoff syndrome is manifest by memory loss and confabulation

Front 28

What is tobacco abuse?

Back 28

1) Squamous cell carcinoma of the larynx, squamous cell and small cell bronchogenic carcinoma, and transitional cell carcinoma of the urinary bladder.
2) Chronic obstructive pulmonary disease
3) Atherosclerosis and other vascular occlusive diseases, such as Buerger disease.

Front 29

What is cocaine abuse?

Back 29

1) Mood elevatin, sometimes followed by irritability, anxiety, and depression which may lead to suicide
2) Increased myocardial irritability, which can lead to fatal arrhythmias.
3) Hypertension, which can predispose to cerebral hemorrhage
4) Nasal congenstion, ulceration, or septal perforation, from intranasal use
5) Burn injury, due to volatile inflammable substances used in cocaine free-base preparation
6) Viral (HIV or Hep B) or bacterial (infective endocarditis) infection (IVDU). Infective endocarditis due to intravenous drug abuse often involves the valves of the right side of the heart.
7) Epileptic seizures, respiratory arrest, myocardial infarction, and, in newborns of addicted mothers, muiple small cerebral infarcts.

Front 30

What is heroin abuse?

Back 30

1) Physical dependence, with severe withdrawal symptoms
2) Infections, such as HIV, hepatitis B, and infective endocarditis
3) Adult respiratory distress syndrome
4) Death from respiratory or cardiac arrest or from pulmonary edema

Front 31

What happens with methyl alcohol injury?

Back 31

1) Converted to the cellular toxins formaldehyde and formic acid, resulting in transient metabolic acidosis.
2) Damages the cells of the retina, optic nerve, and CNS, resulting in blindness.

Front 32

What happens in carbon monoxide injury?

Back 32

1) Inhibits the capacity of hemoglobin to function as an oxygen carrier because hemoglobin has an affinity for CO that is 200 times greater than its affinity for oxygen.
2) Can results in irreversible hypoxic injury, often leading to death; neurons of the brain are most vulnerable. Foci of neuronal necrosis in the basal ganglia, lenticular nuclei, and cortical gray areas are characteristic.
3) When fatal, causes a cherry-red color of the skin, blood, viscera and muscles.

Front 33

What happens in carbon tetrachloride injury?

Back 33

Induces centrilobular necrosis and fatty change in the liver.

Front 34

What happens in cyanide injury?

Back 34

1) Inhibits intracellular cytochrome oxide by binding wiht ferric iron, thus preventing cellular oxidation Death occurs with minutes.
2) Generalized petechial hemorrhages and a scent of bitter almonds are noted at autopsy.

Front 35

What happens in Lead injury?

Back 35

1) Ingested from lead paint
2) inspired from automotive emmissions
3) RBC changes include; basophilic stippling; Hypochromic microcytic anemia
4) Encephalopathy, characterized by irritability and sometimes by seizures and coma
5) Neuropathy, characterized by wristdrop and footdrop
6) Fanconi syndrome, characterized by impaired proximal renal tubular reabsorption of phosphate, glucose, adn amino acids
7) Lead line, characterized by mucosal deposit of lead sulfide at teh junction of the teeth and gums
8) Increased radiodensity of the epiphyses of the long bones.

Front 36

What happens in Mercuric chloride injury?

Back 36

When ingested, results in focal GI ulceration and severe renal damage with widespresd necrosis and calcification of the proximal convoluted tubules. Proximal convuluted tubular necrosis is characteristic of injury from a number of nephrotoxins.

Front 37

What is hypochromic microctic anemia involved in Lead injury?

Back 37

1) Caused by deficient heme synthesis mediated yby the inhibition of delta-aminolevulinic acid (ALA) and by dereased incorporation of iron into heme.
2) Defects result in accumulation of both ALA and erythrocyte protoporphyrin, leading to protoporphyrinemia, porphyrineuria, and aminolevulinic aciduria.

Front 38

What happens in vinyl chloride injury?

Back 38

Can lead to hemangiosarcoma of liver.

Front 39

What happens in Beta-Napthylamine and aniline dyes injury?

Back 39

Can lead to transitional cell carcinoma of the urinary bladder.

Front 40

What happens in ethylene glycol injury?

Back 40

1) Can cause acute tubular necrosis
2) Can also cause tubular precipitation of calcium oxaleate cyrstals, which can be visualized with polarized light.

Front 41

What happens in Polychlorinated biphenyls injury?

Back 41

Nonbiodegradable environmental pollutants that were used to manufacture a variety of products, such as adhesives adn plasticizers. Because of their toxicity, their production is now outlawed.
2) Exposure produces a syndrome of chloracne, impotence, and visual changes.

Front 42

What are the adverse effects of antibiotics?

Back 42

1) Development of drug-resistant organisms; often mediated by plasmids carrying specific drug-resistant genes.
2) Fatal aplastic anemia; can occur as a result of an idiosyncratic reaction to chloramphnicol.

Front 43

What are the adverse effects of sulfonamides?

Back 43

1) Immune complex disease, such as polyarteritis nodosa, which can develop when sulfonamides, acting as haptens, stimulate antibody production
2) Crystallization of sulfonamides within the renal collecting system, causing calculi with obstruction, infection, or both.
3) Bone marrow failure
4) Acute, self-limited hemolytic anemia; may be induced in individuals with erythrocyte glucose-6-phosphate dehydrogenase (G6PD) deficiency.

Front 44

How does aspirin effect GI tract?

Back 44

May be caused by aspirin-induced gastric or peptic ulcer or by inhibition of platelet cyclooxygenase with resultant thromboxane A2 deficiency and impaired platelet plug formation.

Front 45

What is Reye syndrome?

Back 45

1) Occurs in children following an acute febrile viral illness, almost always in association with aspirin intake.
2) Characterized by microvesicular fatty change in the liver adn encephalopathy.

Front 46

What are the allergic reactions to aspirin?

Back 46

Urticaria, asthma, nasal polyps, and angioneurotic edema.

Front 47

What are the adverse effects of Phenacetin?

Back 47

1) Chronic analgesic nephritis adn renal papillary necrosis (the drug and been withdrawn from the US market)
2) Urothelial neoplasms, especially transitional cell carcinoma of the renal pelvis.
3) Acute hemolysis in G6PD-deficient individuals.

Front 48

What are the adverse effects of cancer chemotherapeutic drugs?

Back 48

1) Toxic effects; including hair loss, GI erosions and ulceratoins, and, most significantly, bone marrow failure.
2) Acute leukemia or other malignancies.