Immune Response, Inflammation, and Key Vocabulary

Key Vocabulary

• Active artificial immunity, active natural immunity, anaerobe, aerobe, antibodies, antigen, autoimmune, bactericidal, bacteriostatic, benign, chemotherapy, culture and sensitivity (C&S), host, and inflammation are all key vocabulary terms
• Other important terms include: malignant, metastasis, nosocomial, passive artificial immunity, passive natural immunity, pathogenic and superinfection

The Immune Response

• An antigen invades the body and it responds by attacking the antigen
• Inflammation limits the spread of microbes
• The first phase of an immune response involves the release of bradykinin, complement, histamine and leukotrienes, and prostaglandins
• The second phase launches an attack by secreting antibodies

Types of Immune System Medications

• Anti-inflammatory, anti-infective, antitoxin, antifungal, antiviral, antiparasitic, and antineoplastic chemotherapy drugs, as well as vaccines, can affect the immune system

Anti-Inflammatory Medications

• Anti-inflammatory medications can stop or reduce the inflammatory response
• These medications are useful in patients with auto-immune disorders, such as: rheumatoid arthritis, dermatitis, multiple sclerosis, and systemic lupus erythematosus
• Immunosuppressants are used for long-term therapy of inflammatory diseases
• Azathioprine and cyclosporine treat rheumatoid arthritis
• Cyclosporine and sirolimus treat psoriasis
• Azathioprine is also used for Crohn’s disease

Anti-Infective Medications

• Anti-infective medications are classified by their mechanisms of action or chemical structure, and target the processes of pathogenic microorganisms by: aiding protein synthesis, inhibiting DNA or RNA synthesis, and destroying the cell wall
• Antibiotics treat bacterial infections and affect bacteria by naming them based on their shape, staining, and need for oxygen
• Broad-spectrum antibiotics like vancomycin and gentamicin are effective against many types of bacteria
• Antibiotics can kill healthy or normal flora, resulting in super-infections like yeast.
• Culture and sensitivity tests (C&S) identify bacteria and effective antibiotics

Penicillins

• One of the oldest class of antibiotics, first available since World War II
• Administered orally, topically or injected for common infections
• Kill gram-positive & gram-negative bacteria by destroying cell walls
• Among the least expensive antibiotics available
• Many patients are allergic
• Includes ampicillin, amoxicillin, and penicillin VK

Cephalosporins

• Similar to penicillins, but are more expensive
• There are four generations, based on their activity
• First generation is suitable for patients allergic to penicillin, and treats gram-positive bacteria, like cefazolin and cefaroxil
• The second generation treats nosocomial pneumonia, pelvic or intra-abdominal infections, like cefprozil, cefuroxine
• The third generation treats gram-negative bacteria, like ceftriaxone
• The fourth-generation is administered intravenously for severe nosocomial surgical infections, like cefepime
• Used to treat and prevent infections, but alcohol use can cause abdominal side effects

Tetracyclines

• Bacteria become resistant to this class quickly
• They prevent protein synthesis, thus interrupting reproduction of bacteria
• Effective against many gram-negative and gram-positive microbes
• Can cause permanent staining of teeth in child or fetus, and, so is not suitable for children or pregnant women
• Includes doxycycline, minocycline, and tetracycline

Macrolides

• Inhibit microbial reproduction by inhibiting protein synthesis
• May be either bactericidal or bacteriostatic
• Used to treat myriad infections
• Includes erythromycin, clarithromycin, and azithromycin

Aminoglycosides

• More toxic than other antibiotics
• Require blood level monitoring
• Used only when no other suitable anti-infective is available
• Nephrotoxic and ototoxic
• Ideal against aerobic gram-negative bacteria
• Administered topically via ointments, eye or ear drops, or as an IV injection
• Includes amikacin, gentamicin, and tobramycin

Quinolone Medications

• Bacteriostatic: Prevent bacteria from growing
• Reserved for antibiotic-resistant strains of bacteria due to rare, severe side effects
• Administered via IV, ophthalmic, or oral administrations
• Useful for chronic urinary tract infections as an additional use case
• Includes ciprofloxacin and ofloxacin

Sulfonamides

• One of the earliest classes of antibiotics used
• Kill bacteria by interrupting their metabolism
• Collect in the bladder prior to excretion, which makes them very effective with urinary tract infections
• Many allergies exist for this mediation.
• Includes trimethoprim-sulfamethoxazole and erythromycin-sulfisoxazole

Antituberculosis Agents

• Antibiotics that treat Mycobacterium tuberculosis
• A mixture of two to four medications simultaneously are administered daily for up to 1 year
• Cycloserine: Prevents bacteria from growing in the body
• Rifampin: Treats or prevents TB and turns body secretions red/brown

Antitoxins

• Antibodies created to counteract toxins in persons at high risk for disease or condition
• Useful in treating patients exposed to diphtheria, tetanus, and botulism
• Tetanus immune globulin provides immediate neutralization of tetanus toxoid

Antifungal Medications

• Used to treat Tinea pedis (athlete’s foot) and Candidiasis (yeast infection)
• Topical options include: ketoconazole, miconazole, and nystatin
• Systemic options include: fluconazole, itraconazole, ketoconazole, and Fungizone (Amphotericin B)
• Fungizone is reserved for life-threatening fungal infections due to serious side effects

Viruses

• Viruses require a host to reproduce, e.g. humans, plants, or animals
• They are smaller than other microorganisms
• Insert genetic material into host
• Examples: cytomegalovirus, rabies, smallpox, chickenpox, shingles, influenza, common cold, herpes

Antiviral Medications

• Antiviral therapy inhibits reproduction of viruses
• Most medications shorten the duration of symptoms but do not prevent illness itself
• Valacyclovir: Treats viruses that cause herpes, chickenpox, and shingles
• Zanamivir and oseltamivir: Treat influenza type A and B

Human Immunodeficiency Virus (HIV)

• Understanding the replication cycle of HIV assists in understanding how the pharmacology of HIV medications work
• After the virus enters the body, it attaches to CD4 receptors on T4 (helper) lymphocytes
• The virus uncoats and puts its genetic material into the host T4 cell
• This genetic material forms DNA that is passed to other T4 lymphocytes with the help of a viral enzyme called protease
• After a latent phase, HIV may produce as many as 10 billion virions every day
• Current guidelines recommend that antiretroviral therapy be initiated in all HIV-infected patients to reduce the risk of disease progression

Antiretroviral Medications

• A group of medications to treat retroviruses such as HIV
• Retroviruses imbed genetic material in a gene of healthy cells, making them difficult to fight
• Medications are classified according to where in the reproduction process they act

Antiretroviral Medication Types

• Nucleoside reverse transcriptase inhibitors (NRTIs), such as Lamivudine
• Fusion Inhibitors, like Enfuvirtide
• Protease inhibitors (PIs), like Ritonavir
• HIV integrase strand transfer inhibitors, like Elvitegravir
• CCR5 coreceptor antagonists, like Maraviroc

Antimalarials

• Prevent and treat malaria
• Inhibit the growth of the malaria parasite in the red blood cells of the body
• Includes atovaquone/proguanil, chloroquine, mefloquine, and primaquine

Cancers

• Disorderly and uncontrolled division of cells, usually more rapid than healthy cells
• Nicotine and alcohol can trigger this cell division to begin
• The body is unable to identify abnormal cells
• Metastasis spreads cancerous cells to surrounding or distant body parts

Chemotherapy

• Uses a combination of several antineoplastic and cytotoxic medications
• Treatment is given via IM, IV, SC, or intrathecally
• Creams and gels are available for mild forms of skin cancer
• Each individual receives a combination of medications depending upon their specific cancer diagnosis
• Adverse affects of chemotherapy include, common side effects, caustic effects, and organ damage
• Common side effects are nauseau, vomiting, alopecia and decreased blood counts
  • Caustic side effects are common when inserting central lines and dangerous to those administering medication

Immunomodulators

• Stimulate the immune system in patients with multiple myeloma
• Includes filgristim, lenalidomide, and thalidomide
• Thalidomide pose high risk of birth defects and multiple birth control methods are required

This lesson covers key vocabulary related to the immune system, including types of immunity, microbes, and medical terminology. It explains the immune response, including the role of inflammation and the release of antibodies. It also covers types of medications that affect the immune system, such as anti-inflammatory and anti-infective drugs.