Clinical Toxicology

Vocabulary flashcards covering key terms in clinical toxicology, microbial virulence, and major environmental toxicants discussed in the lecture notes.

Clinical Toxicology

Branch of medicine concerned with diseases caused by or uniquely associated with toxic substances.

Toxin

Poisonous substance produced by biological systems such as plants, animals, fungi, or bacteria.

Virulence Factor

Adaptation that enables a microbe to invade, establish in a host, and cause disease (e.g., toxins, exoenzymes, antiphagocytic factors).

Exoenzyme (Extracellular Enzyme)

Enzyme secreted by pathogens to break down host tissues or dissolve defense barriers.

Mucinase

Exoenzyme that digests mucous membrane coatings; associated with amebic dysentery by Entamoeba.

Keratinase

Exoenzyme that digests keratin of skin and hair; secreted by fungi causing ringworm.

Collagenase

Exoenzyme that breaks down connective-tissue collagen; produced by Clostridium species and some worms.

Hyaluronidase

Exoenzyme that digests hyaluronic acid ‘cement’ between animal cells; virulence factor in staphylococci, streptococci, etc.

Coagulase

Staphylococcal enzyme that clots blood or plasma, aiding immune evasion.

Bacterial Kinases

Enzymes (e.g., streptokinase) that dissolve fibrin clots, helping bacteria spread; also used therapeutically to dissolve human clots.

Toxigenicity

Genetically controlled ability of organisms to produce toxins.

Toxinosis

Disease state caused by toxins; includes toxemia and intoxication.

Toxemia

Condition where toxin spreads through the bloodstream from site of infection (e.g., tetanus).

Intoxication

Disease resulting from ingestion of a pre-formed toxin (e.g., botulism).

Neurotoxin

Toxin that specifically targets nerve tissue.

Enterotoxin

Bacterial toxin that targets intestinal mucosa; produced by E. coli and Staphylococcus aureus.

Hemotoxin

Toxin that destroys red blood cells or disrupts clotting.

Nephrotoxin

Toxin that damages kidney tissue.

Endotoxin

Lipopolysaccharide (LPS) component of Gram-negative outer membrane; released on cell lysis, causing fever and shock.

Exotoxin

Protein toxin secreted by living bacteria; highly potent and target-specific (e.g., botulin, diphtheria toxin).

Hemolysin

Class of exotoxins that lyse red blood cells, releasing hemoglobin.

Phagocytosis

Process by which neutrophils or macrophages engulf and destroy foreign particles or microbes.

Neutrophil

White blood cell that engulfs small particles and microbes during innate immune response.

Macrophage

Large phagocytic cell residing in tissues or circulating, capable of destroying debris and presenting antigens.

Antiphagocytic Factor

Virulence attribute that allows pathogens to evade or kill phagocytes (e.g., capsules, leukocidins).

Leukocidin

Substance produced by Streptococcus and Staphylococcus that is toxic to white blood cells.

Polychlorinated Biphenyls (PCBs)

Persistent halogenated hydrocarbons formerly used in industry; environmental pollutants.

DDT

Organochlorine pesticide; persistent bioaccumulative toxin.

Lead

Cumulative heavy-metal poison accumulating in bone, blood, tissue; major pediatric environmental hazard.

Lead Poisoning

Condition causing neurologic damage, anemia, kidney disease; assessed by blood lead level (BLL).

Blood Lead Level (BLL)

Concentration of lead in blood; ≥70 µg/dL is acutely dangerous in children.

Mercury

Toxic metal existing as elemental, inorganic, or organic compounds; used in industry and dental amalgams.

Methylmercury

Organic mercury compound responsible for Minamata disease; bioaccumulates in fish.

Minamata Disease

Neurologic syndrome from methylmercury poisoning in Minamata Bay, Japan (1930s-1960s).

Chromium (VI)

Hexavalent chromium; carcinogenic form implicated in lung cancer and groundwater contamination.

Erin Brockovich Case

Legal action against PG&E over Cr(VI) groundwater pollution, popularized by 2000 film.

Arsenic

Crystalline metalloid used in pesticides and wood preservatives; chronic exposure linked to carcinogenesis.

Arsenicosis

Chronic arsenic poisoning marked by skin darkening (melanosis) and potential cancers.

Asbestos

Group of six silicate minerals with fibrous structure; inhalation linked to serious lung diseases.

Crocidolite

Blue asbestos fiber; straight, stiff, highly hazardous; strongly associated with asbestosis and cancers.

Amosite

Brown asbestos fiber; less stiff than crocidolite but still hazardous.

Chrysotile

White asbestos fiber; curly morphology; widely used, can also induce mesothelioma and lung cancer.

Asbestosis

Diffuse interstitial scarring of lungs due to asbestos exposure; non-malignant.

Bronchogenic Carcinoma

Malignancy originating in lung tissue, increased risk with asbestos exposure.

Mesothelioma

Cancer of pleural or peritoneal lining strongly linked to asbestos fibers.

Lipopolysaccharide (LPS)

Molecule forming outer membrane of Gram-negative bacteria; basis of endotoxin activity.

Streptokinase

Bacterial kinase used medically to dissolve blood clots; derived from Streptococcus.

Coagulation vs. Fibrinolysis

Coagulase forms clots aiding bacteria; kinases like streptokinase dissolve clots aiding spread.

WHO Lead Guideline

Recommended drinking-water limit for lead is 0.01 mg/L.

Hexavalent Chromium Carcinogenicity

Cr(VI) classified by WHO and EPA as human carcinogen due to lung-cancer risk.