chapter 24 antiinfectives copyright © 2004 by elsevier inc. all rights reserved

Chapter 24Chapter 24

AntiinfectivesAntiinfectives

Copyright © 2004 by Elsevier Inc. All rights reserved.


IntroductionIntroduction

• Immune system:Immune system:

– Body built-in defense systemBody built-in defense system

– Identifies and kills foreign bodiesIdentifies and kills foreign bodies

• Antibiotics–help when invading Antibiotics–help when invading organism gets out of handorganism gets out of hand

• Antibiotic–against lifeAntibiotic–against life



• Antibiotic–natural or synthetic Antibiotic–natural or synthetic substance that inhibits or destroys substance that inhibits or destroys microorganismsmicroorganisms

• Antimicrobial–substances produced Antimicrobial–substances produced by scientists used against human by scientists used against human infectionsinfections

• Normal flora–bacteria residing in Normal flora–bacteria residing in human body (mutually beneficial)human body (mutually beneficial)



• Normal flora–intestines, mouth, throatNormal flora–intestines, mouth, throat

• Antibiotics–bacteriostatic, bactericidalAntibiotics–bacteriostatic, bactericidal

• Bacteriostatic–arrest development or Bacteriostatic–arrest development or stop growth of microbesstop growth of microbes

• Bactericidal–kill microorganismsBactericidal–kill microorganisms


History of AntibioticsHistory of Antibiotics

• 1930s–first antibiotic, sulfa 1930s–first antibiotic, sulfa (sulfanilamide) discovered(sulfanilamide) discovered

• Cure staphylococcus infections–Cure staphylococcus infections–bacteriostaticbacteriostatic

• Mass production–WWIIMass production–WWII

• Used often without regard for Used often without regard for possibility of resistancepossibility of resistance



• Patients take drug–feel better–stop Patients take drug–feel better–stop taking drugtaking drug

• Remaining microbes–build immunity Remaining microbes–build immunity to drug–infection reappears–bacteria to drug–infection reappears–bacteria more resistant to antibioticmore resistant to antibiotic

• Microbes–can alter genetic makeupMicrobes–can alter genetic makeup



• Overuse and misuse of antibiotics– Overuse and misuse of antibiotics– new strains of bacteria make new strains of bacteria make antibiotic ineffectiveantibiotic ineffective

• 1960s–sulfa obsolete1960s–sulfa obsolete

• Limited use today–UTIs, respiratory Limited use today–UTIs, respiratory infectionsinfections


The Discovery of PenicillinThe Discovery of Penicillin

• Alexander Fleming–discovered Alexander Fleming–discovered penicillin by accident–he inadvertently penicillin by accident–he inadvertently contaminated an agar plate with mold contaminated an agar plate with mold called called Penicillium notatumPenicillium notatum

• Zone of clearance (chemicals from Zone of clearance (chemicals from mold kill off surrounding mold kill off surrounding microorganisms on plate)microorganisms on plate)


A petri dish is prepared with nutrient-rich agar. This nutrient A petri dish is prepared with nutrient-rich agar. This nutrient feeds the bacteria which are placed on the plate. The penicillium feeds the bacteria which are placed on the plate. The penicillium colony can be seen with an area of clearance where the bacteria colony can be seen with an area of clearance where the bacteria cannot grow. This occurs because the penicillium inhibits the cannot grow. This occurs because the penicillium inhibits the bacterial growth.bacterial growth.



• Penicillin agents–around since 1940s–Penicillin agents–around since 1940s–very effective; bactericidal effect very effective; bactericidal effect toward gram-positive bacteriatoward gram-positive bacteria

• 100 individual drugs–available to 100 individual drugs–available to combat range of infectionscombat range of infections


Gram StainGram Stain

• Hans Christian Gram–developed Hans Christian Gram–developed Gram stain procedure in 1883Gram stain procedure in 1883

• Determine morphology (shape and Determine morphology (shape and appearance) of bacteriaappearance) of bacteria

• Gram-positive–bacteria have thick Gram-positive–bacteria have thick outer membrane made of outer membrane made of peptidoglycan linkspeptidoglycan links


Gram StainGram Stain

• Penicillin–enters links, breaks them, Penicillin–enters links, breaks them, kills themkills them

• Gram-negative–different type of cell Gram-negative–different type of cell wall; harder to killwall; harder to kill

• Newer antibiotics–kill gram-negative Newer antibiotics–kill gram-negative microorganismsmicroorganisms


Modern AntibioticsModern Antibiotics

• Penicillinase-producing microbes–Penicillinase-producing microbes–made penicillin ineffectivemade penicillin ineffective

• Amoxicillin + clavulanate–Augmentin Amoxicillin + clavulanate–Augmentin (strengthens penicillin)(strengthens penicillin)

• Ampicillin + sulbactam–UnasynAmpicillin + sulbactam–Unasyn

• Agents–inhibit the penicillinase Agents–inhibit the penicillinase enzymes from breaking down the enzymes from breaking down the antibioticantibiotic


Types of Infections Types of Infections and Their Treatmentsand Their Treatments

• Common infections–can appear Common infections–can appear anywhere on or within the bodyanywhere on or within the body

• Cause–exposure to environment, Cause–exposure to environment, foods we eat, contact with othersfoods we eat, contact with others

• Types of microorganisms include Types of microorganisms include bacteria, fungi, protozoa, viruses (not bacteria, fungi, protozoa, viruses (not technically an organism), and technically an organism), and multicellular microscopic parasitesmulticellular microscopic parasites


Types of Infections Types of Infections and Their Treatmentsand Their Treatments

• Internal body–normally a sterile Internal body–normally a sterile environment (does not include parts environment (does not include parts open to the environment or those that open to the environment or those that contain outside substances)contain outside substances)

• Body–subject to bacterial, viral, Body–subject to bacterial, viral, parasitic infectionsparasitic infections

• Common areas to be infected–male and Common areas to be infected–male and female genital systems; GI tract; upper female genital systems; GI tract; upper and lower respiratory system; skin; and lower respiratory system; skin; nose and mouth; eyes and earsnose and mouth; eyes and ears


Sexually Transmitted Diseases Sexually Transmitted Diseases (STDs)(STDs)

• Caused by various bacteria, protozoal Caused by various bacteria, protozoal organisms, and virusesorganisms, and viruses

• Can do permanent damage to internal Can do permanent damage to internal organsorgans

• Must be treated with correct antibioticMust be treated with correct antibiotic


Gastrointestinal (GI) Infections Gastrointestinal (GI) Infections

• Stomach–highly acidic environment Stomach–highly acidic environment usually destroys any bacteriausually destroys any bacteria

• Stomach lining injured, juices not Stomach lining injured, juices not strong enough to kill microbes–strong enough to kill microbes–infections occurinfections occur

• Helicobacter pyloriHelicobacter pylori–major infection –major infection of stomachof stomach


GI InfectionsGI Infections

• H. pyloriH. pylori–triple drug therapy used –triple drug therapy used to eradicate: tetracycline, Septra, to eradicate: tetracycline, Septra, metronidazole (bactericidal effect metronidazole (bactericidal effect on bacilli)on bacilli)

• Other areas susceptible to infection–Other areas susceptible to infection–mouth, throat, tracheamouth, throat, trachea


GI infectionsGI infections

• Anaerobic microbes–do not live in airAnaerobic microbes–do not live in air

• Aerobic microbes–live in airAerobic microbes–live in air

• Facultative anaerobes–tolerate Facultative anaerobes–tolerate oxygen to a certain degreeoxygen to a certain degree


Respiratory InfectionsRespiratory Infections

• Small particles, microorganisms– Small particles, microorganisms– inhaled on dust (bacteria, fungus, inhaled on dust (bacteria, fungus, viruses)viruses)

• Settle in airways and cause infectionSettle in airways and cause infection

• Common symptoms–wheezing, Common symptoms–wheezing, coughing, shortness of breathcoughing, shortness of breath

• Pneumonia–most serious respiratory Pneumonia–most serious respiratory infectioninfection



• Pneumonia:Pneumonia:

– Infection of the lungsInfection of the lungs

– Caused by bacteria, viruses, fungi, Caused by bacteria, viruses, fungi, parasites, chemicalsparasites, chemicals

– Nosocomial–acquired in hospitals Nosocomial–acquired in hospitals or nursing homesor nursing homes



• Elderly and bedridden patients–high Elderly and bedridden patients–high risk of acquiring pneumoniarisk of acquiring pneumonia

• Patients with chronic conditions high Patients with chronic conditions high risk also–emphysema, bronchitis, risk also–emphysema, bronchitis, asthma, immunosuppressive disordersasthma, immunosuppressive disorders

• TB–highly contagious, caused by TB–highly contagious, caused by Mycobacterium tuberculosisMycobacterium tuberculosis



• TB–causes inflammation, abscesses, TB–causes inflammation, abscesses, necrosis, fibrosis of respiratory necrosis, fibrosis of respiratory system (can spread to other parts system (can spread to other parts of the body)of the body)

• HIV and AIDS–contributes to rise in TBHIV and AIDS–contributes to rise in TB

• Symptoms–chronic coughing, fever, Symptoms–chronic coughing, fever, sweating, weight losssweating, weight loss

• Diagnosed by TB skin test and sputumDiagnosed by TB skin test and sputum



• Fungal infections–more prone to Fungal infections–more prone to infect patients with: infect patients with:

– Other major illnesses, such as Other major illnesses, such as cystic fibrosiscystic fibrosis

– Compromised immune systems Compromised immune systems (AIDS, cancer patients on (AIDS, cancer patients on chemotherapy, patients on multiple chemotherapy, patients on multiple antibiotics)antibiotics)



• Two most common fungal infections– Two most common fungal infections– Candida albicans, Aspergillus Candida albicans, Aspergillus fumigatusfumigatus

• Bacterial infections–secondary to Bacterial infections–secondary to chemical exposure–toxins that are chemical exposure–toxins that are inhaled in fumesinhaled in fumes

• Asbestos–if inhaled, causes scarring Asbestos–if inhaled, causes scarring of lungs; decreases the capacity of of lungs; decreases the capacity of lungs to take in oxygenlungs to take in oxygen


Nosocomial InfectionsNosocomial Infections

• Infections acquired in hospitals and Infections acquired in hospitals and nursing homesnursing homes

• Hand sanitization and handwashing Hand sanitization and handwashing major steps to prevention of major steps to prevention of nosocomial infectionsnosocomial infections

• Can be deadlyCan be deadly

• Can be bacterial, fungal, viralCan be bacterial, fungal, viral

• Hard to fightHard to fight


Infections of the SkinInfections of the Skin

• Children–skin abrasions, cuts, scrapesChildren–skin abrasions, cuts, scrapes

• Keep clean and free from bacteriaKeep clean and free from bacteria

• Diabetics–high risk of infections of Diabetics–high risk of infections of skin; lack of blood flow to extremities, skin; lack of blood flow to extremities, cause septic infections, gangrenecause septic infections, gangrene

• Hospitalization, strong antibiotics Hospitalization, strong antibiotics necessarynecessary


Infections of the SkinInfections of the Skin

• Fungal infections–common on skin Fungal infections–common on skin surfacesurface

• Fungus–needs high concentration of Fungus–needs high concentration of oxygen to liveoxygen to live

• Common fungal infection–Tinea pedis Common fungal infection–Tinea pedis (athlete’s foot)(athlete’s foot)

• OTC medications availableOTC medications available


Infections of Nose and MouthInfections of Nose and Mouth

• Nose and mouth–constant contact Nose and mouth–constant contact with air-borne microbeswith air-borne microbes

• Minor colds, flulike symptoms–OTC Minor colds, flulike symptoms–OTC products bring reliefproducts bring relief

• Colds, flu–viral; antibiotics useless Colds, flu–viral; antibiotics useless against themagainst them


Infections of Eyes and EyesInfections of Eyes and Eyes

• Eyes, ears–susceptible to infections Eyes, ears–susceptible to infections because of exposure to environmentbecause of exposure to environment

• Conjunctivitis–most common eye Conjunctivitis–most common eye infection; inflammation of lining of infection; inflammation of lining of eyelids and cornea (conjunctiva)eyelids and cornea (conjunctiva)

• Styes–appear on eyelids–discharge of Styes–appear on eyelids–discharge of puspus

• Seasonal allergies–cause conjunctivitisSeasonal allergies–cause conjunctivitis


Infections of Eyes and EarsInfections of Eyes and Ears

• Otitis media–common ear infection Otitis media–common ear infection in babies and childrenin babies and children

• Two types–acute and chronicTwo types–acute and chronic

• Acute–bacterial infection begins as Acute–bacterial infection begins as upper respiratory infection then upper respiratory infection then proceeds to infect earproceeds to infect ear


Infections of Eyes and MouthInfections of Eyes and Mouth

• Chronic form–repeated infections; Chronic form–repeated infections; cause inflammation of tympanic cause inflammation of tympanic membrane; very painfulmembrane; very painful

• Chronic otitis media–may also result Chronic otitis media–may also result from rupture of tympanic membranefrom rupture of tympanic membrane


Antibiotic TreatmentsAntibiotic Treatments

• Antibiotics–referred to as wide-Antibiotics–referred to as wide-spectrum or narrow-spectrum agentsspectrum or narrow-spectrum agents

• Narrow-spectrum–covers mostly Narrow-spectrum–covers mostly gram-positive microbesgram-positive microbes

• Wide-spectrum–covers gram-positive Wide-spectrum–covers gram-positive and gram-negative microbesand gram-negative microbes


PenicillinPenicillin

• Taken from two different molds–Taken from two different molds–Penicillium notatum Penicillium notatum andand Penicillium Penicillium chryogenumchryogenum

• Grown in laboratories and synthetically Grown in laboratories and synthetically altered to fight off microorganismsaltered to fight off microorganisms

• Drug action–bactericidal against Drug action–bactericidal against currently reproducing bacteriacurrently reproducing bacteria



• Disrupt formation of cell wall so that Disrupt formation of cell wall so that bacteria cannot keep a constant bacteria cannot keep a constant osmotic gradient and lyses (breaks osmotic gradient and lyses (breaks open)open)

• Penicillin-type agents–cover mostly Penicillin-type agents–cover mostly gram-positive organismsgram-positive organisms

• Susceptible to stomach acid Susceptible to stomach acid degradation–take 1 to 2 hours degradation–take 1 to 2 hours after mealsafter meals



• Infections of GI system–more potent Infections of GI system–more potent antibiotics requiredantibiotics required

• Broader spectrum “cillins”–ampicillin Broader spectrum “cillins”–ampicillin and carbenicillin–kill both gram-and carbenicillin–kill both gram-positive and gram-negative organismspositive and gram-negative organisms

• Allergy–nausea, vomiting, diarrhea, Allergy–nausea, vomiting, diarrhea, headache, sore mouth, rashes, pain, headache, sore mouth, rashes, pain, fever fever


CephalosporinCephalosporin

• Less affected by stomach acidsLess affected by stomach acids

• Can be taken with mealsCan be taken with meals

• 10% chance of allergic reaction for 10% chance of allergic reaction for those with penicillin allergiesthose with penicillin allergies

• Cephalosporin drug listing Cephalosporin drug listing


Mycobacterium and Mycobacterium and Mycobacterial TreatmentMycobacterial Treatment

• Two main infections in humans Two main infections in humans caused by mycobacterium–TB, caused by mycobacterium–TB, LeprosyLeprosy

• Both infections–chronicBoth infections–chronic

• Leprosy (Hansen’s disease)–caused Leprosy (Hansen’s disease)–caused by by Mycobacterium lepraeMycobacterium leprae


Leprosy (Hansen’s Disease) Leprosy (Hansen’s Disease)

• Caused by Caused by Mycobacterium lepraeMycobacterium leprae

• Skin lesions appear, ulceration of Skin lesions appear, ulceration of feet, loss of hand function, corneal feet, loss of hand function, corneal abrasions, blindnessabrasions, blindness

• Can be treated with dapsone Can be treated with dapsone (bacteriostatic) and clofazimine (bacteriostatic) and clofazimine (bactericidal)(bactericidal)


TBTB

• Wasting disease–robs person of Wasting disease–robs person of breath and strengthbreath and strength

• Many people quit taking medicine Many people quit taking medicine once they felt better–microbe able to once they felt better–microbe able to withstand low doses of antibiotics withstand low doses of antibiotics until became resistantuntil became resistant

• 2/3 prisoners have TB–no medication 2/3 prisoners have TB–no medication available to combat diseaseavailable to combat disease


TBTB

• Few antituberculin-type medicationsFew antituberculin-type medications

• Must be taken for full course of Must be taken for full course of treatment (6 months or years treatment (6 months or years depending on test results)depending on test results)


Antituberculin AgentsAntituberculin AgentsDosingDosing LengthLength

GenericGeneric TradeTrade RegimenRegimen of Timeof Time

IsoniazidIsoniazid Abbreviation: INHAbbreviation: INH 300 mg qd300 mg qd 6-24 months6-24 months

RifampinRifampin RifadinRifadin 600 mg qd600 mg qd Months Months to yearsto years

EthambutolEthambutol MyambutolMyambutol 800 mg to 800 mg to MonthsMonths1.6 gm qd1.6 gm qd to yearsto years

PyrazinamidePyrazinamide PyrazinamidePyrazinamide 1-2 gm qd1-2 gm qd Months Months to yearsto years

CycloserineCycloserine SeromycinSeromycin 750 mg to750 mg to Bacteriostatic: Bacteriostatic: 1 gm qd1 gm qd used for used for

retreatmentretreatment

KanamycinKanamycin KantrexKantrex 500 mg to500 mg to Bactericidal: Bactericidal: 1 gm qd1 gm qd used for used for

retreatmentretreatment


AminoglycosidesAminoglycosides

• Strongest agents in use todayStrongest agents in use today

• Bactericidal for many gram-negative Bactericidal for many gram-negative microorganismsmicroorganisms

• Drug action–(parenteral) ability to Drug action–(parenteral) ability to bind to ribosomes of microorganism bind to ribosomes of microorganism stopping protein synthesis, causing stopping protein synthesis, causing deathdeath

• Narrow range between therapeutic Narrow range between therapeutic and toxic levelsand toxic levels


AminoglycosidesAminoglycosides

• Calculations needed to determine Calculations needed to determine appropriate dosageappropriate dosage

• Patient’s blood levels of antibiotic Patient’s blood levels of antibiotic at peak and trough levels drawn for at peak and trough levels drawn for evaluationevaluation

• Patients with renal disease and older Patients with renal disease and older adults–more susceptible to toxic levelsadults–more susceptible to toxic levels


Additional AntibioticsAdditional Antibiotics

• Drug action, indications Drug action, indications


Antibiotic Reference Table 3Antibiotic Reference Table 3

ClassClass GenericGeneric TradeTrade IndicationIndication Drug actionDrug action

Tetracyclines*Tetracyclines* doxycyclinedoxycycline VibramycinVibramycin Severe infections Severe infections IPS*IPS*tetracyclinetetracycline AchromycinAchromycin such as respiratory, such as respiratory, minocyclineminocycline MinocinMinocin GI, and skinGI, and skin

Fluoroquinolones†Fluoroquinolones† ciprofloxacinciprofloxacin CiproCipro TB, Respiratory, TB, Respiratory, IBDNAS*IBDNAS*levofloxacinlevofloxacin LevaquinLevaquin and UTIsand UTIsofloxacinofloxacin FloxinFloxinnorfloxacinnorfloxacin NoroxinNoroxin

MacrolidesMacrolides azithromycinazithromycin ZithromaxZithromax Respiratory, genital,Respiratory, genital, IPS*IPS*clarithromycinclarithromycin BiaxinBiaxin GI, and skin GI, and skin erythromycinerythromycin Emycin, Ery-Tab Emycin, Ery-Tab infectionsinfectionserythro erythro EESEESethylsuccinateethylsuccinateerythromycin erythromycin ErythrocinErythrocinstatestate


Antibiotic Reference Table 3Antibiotic Reference Table 3(continued)(continued)

ClassClass GenericGeneric TradeTrade IndicationIndication Drug actionDrug action

CarbapenemsCarbapenems imipenem/imipenem/ PrimaxinPrimaxin Serious infectionsSerious infections IBCWS* IBCWS* cilastincilastin

Monobactam Monobactam aztreonamaztreonam AzactamAzactam Wide-spectrum Wide-spectrum IBCWS*IBCWS*gram-negativegram-negativeaerobicaerobicorganismsorganisms

Vancomycin Vancomycin vancomycinvancomycin VancocinVancocin Serious/severe Serious/severe IBCWS*IBCWS*infectionsinfections

GI, gastrointestinal; IBCWS, inhibits bacterial cell wall synthesis; IBDNAS, interferes with bacterial DNA GI, gastrointestinal; IBCWS, inhibits bacterial cell wall synthesis; IBDNAS, interferes with bacterial DNA synthesis; IPS, inhibits protein synthesis; TB, tuberculosis; UTI, urinary tract infection.synthesis; IPS, inhibits protein synthesis; TB, tuberculosis; UTI, urinary tract infection.

*Auxiliary labels: Take on an empty stomach. Take with plenty of water. Avoid dairy products. Avoid *Auxiliary labels: Take on an empty stomach. Take with plenty of water. Avoid dairy products. Avoid antacids.antacids. Avoid direct sunlight.Avoid direct sunlight.

†Auxiliary labels: Do not take antacids. Avoid iron/zinc supplements 4 hours before or 2 hours after †Auxiliary labels: Do not take antacids. Avoid iron/zinc supplements 4 hours before or 2 hours after taking domestication.taking domestication.

This medication may be either bacteriostatic or bactericidal depending on strength of dosageThis medication may be either bacteriostatic or bactericidal depending on strength of dosage


AntifungalsAntifungals

• Fungi–plantlike organisms–grow on Fungi–plantlike organisms–grow on cloth, food, showers, people, warm cloth, food, showers, people, warm moist environmentmoist environment

• Absorb nutrients from environment Absorb nutrients from environment or hosts (animals, humans)or hosts (animals, humans)

• Affect outside of body, not life Affect outside of body, not life threatening, great annoyance; threatening, great annoyance; systemic infection more serious systemic infection more serious


Candida Candida InfectionsInfections

• Candida albicansCandida albicans–resides inside –resides inside human body; gets out of control in human body; gets out of control in weakened immune systemweakened immune system

• CandidaCandida–different species; –different species; responsible for infections in mouth, responsible for infections in mouth, vagina, under finger/toe nailsvagina, under finger/toe nails

• Dermatophytic infections–on skinDermatophytic infections–on skin


CandidaCandida Infections Infections

• Agents applied directly to skinAgents applied directly to skin

• Infection in bloodstream–parenterals Infection in bloodstream–parenterals usedused

• Topical agents–lotions, creams, Topical agents–lotions, creams, ointment, powders, spraysointment, powders, sprays

• Available OTC (fungicidal, fungistatic)Available OTC (fungicidal, fungistatic)


Tinea InfectionsTinea Infections

• Dermatophytosis–caused by Dermatophytosis–caused by Trichophyton, Trichophyton, microsporum,microsporum, oror EpidermophytonEpidermophyton fungusfungus

• Tinea pedis (Athlete’s foot)Tinea pedis (Athlete’s foot)

• Tinea capitis or ringworm–in scalpTinea capitis or ringworm–in scalp

• Babies in groin area–cruris or Babies in groin area–cruris or diaper rashdiaper rash


ParasitesParasites

• Benefit at the expense of anotherBenefit at the expense of another

• Host–organism being used by parasiteHost–organism being used by parasite

• Kingdom Protista–Phylum SporozoaKingdom Protista–Phylum Sporozoa

• Morphology–multicellular or Morphology–multicellular or unicellular and how transmittedunicellular and how transmitted


Parasitic Organisms Parasitic Organisms And Their DescriptionAnd Their DescriptionCiliaCilia Hairlike structures that work Hairlike structures that work

like oars moving the organism like oars moving the organism alongalong

FlagellaFlagella A whiplike tail that propels A whiplike tail that propels the organism alongthe organism along

PseudopodiaPseudopodia Footlike protrusions that move Footlike protrusions that move the organism slowly alongthe organism slowly along

StationaryStationary A cyst form that waits for an A cyst form that waits for an opportunistic environment opportunistic environment

before regeneratingbefore regenerating


Protozoal Infections and Their Protozoal Infections and Their TreatmentsTreatments

SpeciesSpecies Disease nameDisease name TransmissionTransmission TreatmentTreatment

Toxoplasma gondiiToxoplasma gondii ToxoplasmosisToxoplasmosis Contaminated food,Contaminated food, Pyrimethaminesulf-Pyrimethaminesulf-water, feces of a water, feces of a diazine Trimethoprim/diazine Trimethoprim/bug or cat. Sandbug or cat. Sand sulfamethoxazolesulfamethoxazoleflies, tsetse flies alsoflies, tsetse flies also Pentamidine (IV)Pentamidine (IV)carry the diseasecarry the disease AzithromycinAzithromycin

Plasmodium vivaxPlasmodium vivax MalariaMalaria Female mosquitoesFemale mosquitoes ChloroquineChloroquineQuinineQuinineMefloquineMefloquinePrimaquinePrimaquine


Parasitic Conditions–ProtozoaParasitic Conditions–Protozoa

• Human parasites–many protozoaHuman parasites–many protozoa

• Amebiasis–caused by Amebiasis–caused by Entamoeba Entamoeba histolyticahistolytica

• Cyst form–transmitted via fecal-oral Cyst form–transmitted via fecal-oral routesroutes

• Symptoms–abdominal pain, nausea, Symptoms–abdominal pain, nausea, flatulence, fatigueflatulence, fatigue



• Treatment–Iodoquinol–rids body of Treatment–Iodoquinol–rids body of infestationinfestation

• Toxoplasmosis–most dangerous Toxoplasmosis–most dangerous to humansto humans

• Toxoplasma gondiiToxoplasma gondii–transferred via –transferred via uncooked meat or cysts present in uncooked meat or cysts present in cat feces; deadly to both infants and cat feces; deadly to both infants and unborn fetusunborn fetus

• Treatment–pyrimethamine, Treatment–pyrimethamine, sulfadiazinesulfadiazine



• Trichomoniasis–caused by Trichomoniasis–caused by Trichomonas vaginalisTrichomonas vaginalis–affects –affects vaginal areavaginal area

• Protozoa–affects male and female Protozoa–affects male and female urethraurethra

• Metronidazole–drug of choice–must Metronidazole–drug of choice–must be used by both sexual partnersbe used by both sexual partners


Helminths (Worms)Helminths (Worms)

• Parasitic worms; multicellularParasitic worms; multicellular

• Two major worms:Two major worms:

– Roundworms (nematodes) Roundworms (nematodes)

– Flatworms (platyhelminthes)Flatworms (platyhelminthes)

• Roundworms–50 species that affect Roundworms–50 species that affect humans (transferred in undercooked humans (transferred in undercooked meat)meat)



• Some species lodge in the intestines Some species lodge in the intestines or lymph nodes, causing harm to hostor lymph nodes, causing harm to host

• Hookworms (type of roundworm)– Hookworms (type of roundworm)– transferred via feces through skin transferred via feces through skin contactcontact

• Flatworms–tapeworms and flukesFlatworms–tapeworms and flukes

• Live by feeding off dead matter or Live by feeding off dead matter or small organisms (not harmful to small organisms (not harmful to humans)humans)



• Tapeworms–reside in intestines Tapeworms–reside in intestines where they absorb food from hostwhere they absorb food from host

• Eating undercooked meat transfers Eating undercooked meat transfers them to humansthem to humans

• Flukes–acquired from water drunk Flukes–acquired from water drunk from feces-contaminated waterfrom feces-contaminated water



• Many infections occur:Many infections occur:

– In people who live in areas where In people who live in areas where sanitation is nonexistentsanitation is nonexistent

– Where people are not aware Where people are not aware of problemof problem

– Eating raw meatEating raw meat


Antihelminthes Antihelminthes and Their Treatmentsand Their Treatments

Species or Species or Disease NameDisease Name SymptomsSymptoms TreatmentTreatment

Phylum NematodaPhylum Nematoda

RoundwormsRoundworms TrichinosisTrichinosis InflammationInflammation Diethylcarbamazine,Diethylcarbamazine,ivermectinivermectin

HookwormsHookworms AnkylostomaAnkylostoma Anemia,Anemia, Mebendazole,Mebendazole,duodenale,duodenale, weakness, weakness, albendazole, pyrantelalbendazole, pyrantelamericanus americanus fatiguefatigue

PinwormsPinworms EnterobiusEnterobius Anal itchingAnal itching Mebendazole,Mebendazole,vermicularisvermicularis albendazole, pyrantelalbendazole, pyrantel

Bladder wormBladder worm CysticercusCysticercus Forms a cyst Forms a cyst PraziquantelPraziquantelthat can be as that can be as large as anlarge as anorange: orange: symptoms vary symptoms vary depending ondepending onarea infectedarea infected


Antihelminthes Antihelminthes and Their Treatments and Their Treatments (continued)(continued)

Species or Species or Disease NameDisease Name SymptomsSymptoms TreatmentTreatment

PhylumPhylumPlatyhelminthesPlatyhelminthes

TapewormsTapeworms Taenia saginata,Taenia saginata, Diarrhea, weightDiarrhea, weight Praziquantel,Praziquantel,Taenia soliumTaenia solium loss, perforationloss, perforation niclosamideniclosamide

of intestineof intestine

FlukesFlukes SchistosomiasisSchistosomiasis Loss of bloodLoss of blood PraziquantelPraziquantelin fecesin feces


Parasitic TreatmentsParasitic Treatments

• Few ways to deal with parasites:Few ways to deal with parasites:

– Kill them and wash them awayKill them and wash them away

– Rid them from body alive or deadRid them from body alive or dead

– Surgically remove themSurgically remove them

– Agents–all oral dosage formsAgents–all oral dosage forms

• Main goal–remove from bodyMain goal–remove from body


Parasitic TreatmentsParasitic Treatments

• Dosage regimen–short term; done in Dosage regimen–short term; done in few oral dosesfew oral doses

• All parasites–cause damage to All parasites–cause damage to tissues or organs invadedtissues or organs invaded

• Weaken but do not kill host Weaken but do not kill host (food and shelter cut off)(food and shelter cut off)


Antihelminthic Agents Action of Antihelminthic Agents Action of Drug and Common DosageDrug and Common Dosage

GenericGeneric TradeTrade Drug ActionDrug Action Common DosageCommon Dosage

DiethylcarbamazineDiethylcarbamazine HetrazanHetrazan Cidal: increases theCidal: increases the 2-3mg/kg po tid2-3mg/kg po tidloss of filariae, loss of filariae, decreases ability todecreases ability toproduce moreproduce more

MebendazoleMebendazole VermoxVermox Vermicidal: stops Vermicidal: stops 100mg po bid x 3 days100mg po bid x 3 daysglucose uptake inglucose uptake inwormworm

NiclosamideNiclosamide NiclocideNiclocide Cidal: affectsCidal: affects 8gm x 1 dose or 2gm 8gm x 1 dose or 2gm mitochondriamitochondria po qd x 1 weekpo qd x 1 weekdecreases metabolismdecreases metabolism (depends on type (depends on type

of worm infestation)of worm infestation)

OxamniquineOxamniquine VansilVansil Cidal: causes worms Cidal: causes worms 12-15mg/kg po x 1 12-15mg/kg po x 1 to move to liver to move to liver (dose may vary (dose may vary where they are killedwhere they are killed depending on type depending on type

of worm infestation)of worm infestation)


Antihelminthic Agents Action of Antihelminthic Agents Action of Drug and Common Dosage Drug and Common Dosage (continued)(continued)

GenericGeneric TradeTrade Drug ActionDrug Action Common DosageCommon Dosage

PraziquantelPraziquantel BiltricideBiltricide Paralysis: causesParalysis: causes 25mg/kg pd 25mg/kg pd loss of calcium and loss of calcium and tid x 1 daytid x 1 dayeventual paralysis eventual paralysis of worm which is of worm which is then flushed outthen flushed out

PyrantelPyrantel AntiminthAntiminth Paralysis: causesParalysis: causes 11mg/kg po x 1 dose 11mg/kg po x 1 dose depolarization and depolarization and May be repeated May be repeated

eventual paralysiseventual paralysis in 2-3 weeks if in 2-3 weeks if of worm which is of worm which is necessarynecessarythen flushed outthen flushed out

ThiabendazoleThiabendazole MintezolMintezol Vermicidal: inhibitsVermicidal: inhibits 25mg/kg po 25mg/kg po essential enzymesessential enzymes bid x 2 days bid x 2 dayscausing deathcausing death


MalariaMalaria

• Sporozoan infectionSporozoan infection

• Symptoms–fever, chills, sweating, Symptoms–fever, chills, sweating, headache, nauseaheadache, nausea

• PlasmodiumPlasmodium–four species responsible –four species responsible for malariafor malaria

• FalciparumFalciparum–cause death–cause death


MalariaMalaria

• Human body–site of sporozoan Human body–site of sporozoan reproduction (reservoir)reproduction (reservoir)

• Transmission–infected mosquitoTransmission–infected mosquito

• Sporozoa–can be transmitted by Sporozoa–can be transmitted by infected needles or syringes, blood infected needles or syringes, blood transfusiontransfusion

• Incubation period–1 week to 1 month Incubation period–1 week to 1 month


MalariaMalaria

• Prevention and control–control Prevention and control–control mosquitoes by insect repellants, fill mosquitoes by insect repellants, fill in water holes, insecticidesin water holes, insecticides

• Diagnosis–blood smearsDiagnosis–blood smears

• Treatment–Chloroquine phosphateTreatment–Chloroquine phosphate

• Resistant strain–mefloquine, Resistant strain–mefloquine, doxycycline, primaquine doxycycline, primaquine


AntiviralsAntivirals

• Viruses–cannot live outside of hostsViruses–cannot live outside of hosts

• Classification–nucleic acid makeup, Classification–nucleic acid makeup, size, host it infects, enveloped or size, host it infects, enveloped or nakednaked

• Viruses–need host’s DNA to replicateViruses–need host’s DNA to replicate

• Kill host’s cell on leaving or bud off Kill host’s cell on leaving or bud off allowing further reinfectionsallowing further reinfections



• Viruses–do not have ability to Viruses–do not have ability to reproduce themselves in same way reproduce themselves in same way as other organisms doas other organisms do

• Makeup closely related to human DNAMakeup closely related to human DNA

• Agents used to destroy virus also Agents used to destroy virus also destroy human cellsdestroy human cells



• Viral diseases–chicken pox, colds, Viral diseases–chicken pox, colds, influenza, polio, rabies, warts, HIV, influenza, polio, rabies, warts, HIV, AIDS, cancerAIDS, cancer

• Five steps in invasion of virions Five steps in invasion of virions

• Antivirals drug actionAntivirals drug action


Colds/FluColds/Flu

• No cure; caused by virusesNo cure; caused by viruses

• Viruses–mutate very well; change Viruses–mutate very well; change every yearevery year

• Influenzas–can cause death in older Influenzas–can cause death in older adults and immunocompromised adults and immunocompromised personspersons

• Vaccines–given each year to higher Vaccines–given each year to higher risk personsrisk persons


HIV/AIDSHIV/AIDS

• Bloodborne, sexually transmitted Bloodborne, sexually transmitted virusvirus

• No cureNo cure

• Virion–does not cause death; renders Virion–does not cause death; renders host too weak to fight off infectionshost too weak to fight off infections

• HIV virus–attacks immune system of HIV virus–attacks immune system of humanshumans

• Transmitted by body fluids containing Transmitted by body fluids containing virusvirus


HIV/AIDSHIV/AIDS

• Practice safe sexPractice safe sex

• Medical settings–protective wear Medical settings–protective wear decreases risk of contaminationdecreases risk of contamination

• Beginning stages of HIV–body Beginning stages of HIV–body weakens, T4 lymphocytes decreaseweakens, T4 lymphocytes decrease

• T-cell count below 200–AIDST-cell count below 200–AIDS


HIV/AIDSHIV/AIDS

• Treatments–for both HIV and AIDSTreatments–for both HIV and AIDS

• Aimed at controlling progression of Aimed at controlling progression of disease but cannot cure itdisease but cannot cure it

• Only way to avoid disease–prevent Only way to avoid disease–prevent contracting itcontracting it


Miscellaneous Viral ConditionsMiscellaneous Viral Conditions

• Papillomavirus–causes common wartsPapillomavirus–causes common warts

• OTC medications available–Wart-OffOTC medications available–Wart-Off

• Herpes viruses–three main typesHerpes viruses–three main types

• Herpes simplex type 1 and type 2Herpes simplex type 1 and type 2

• Herpes zosterHerpes zoster



• Herpes type 1–causes blisters on Herpes type 1–causes blisters on surface of skin; can cause blindness surface of skin; can cause blindness if left untreatedif left untreated

• Herpes type 2–causes infection in Herpes type 2–causes infection in both adults and neonates (contracts both adults and neonates (contracts it during birth)it during birth)

• Herpes zoster–affects nerve endings; Herpes zoster–affects nerve endings; severe pain (shingles)severe pain (shingles)



• Herpes zoster–cyclical reinfectionsHerpes zoster–cyclical reinfections

• Also causes chicken poxAlso causes chicken pox


ImmunityImmunity

• Two types:Two types:

– Active or passiveActive or passive

• Active–occurs if immunity is from Active–occurs if immunity is from antibodies produced by the body antibodies produced by the body (natural or artificial)(natural or artificial)

• Passive–natural or artificialPassive–natural or artificial

chapter 24 antiinfectives copyright © 2004 by elsevier inc. all rights reserved

Documents