Respimicro [recovered]

24Microbial Diseases of the Respiratory SystemMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

upper respiratory system The consists of the nose, pharynx, and associated structures, such as the middle ear and auditory tubes.Coarse hairs in the noseciliated mucous membranes ( nose and throat )Lymphoid tissue, tonsils, and adenoidsMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

lower respiratory system consists of the larynx, trachea, bronchial tubes, and alveoli.ciliary escalatoralveolar macrophages.Respiratory mucus contains IgA antibodies.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Normal Microbiota of the Respiratory SystemThe normal microbiota of the nasal cavity and throat can include pathogenic microorganisms.The lower respiratory system is usually sterile because of the action of the ciliary escalator.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Upper Respiratory SystemUpper respiratory normal microbiota may include pathogensFigure 24.1MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Microbial Diseases of the Upper Respiratory SystemLaryngitis: S. pneumoniae, S. pyogenes, virusesTonsillitis: S. pneumoniae, S. pyogenes, virusesSinusitis: BacteriaEpiglottitis: H. influenzaeHib vaccineMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Microbial Diseases of the Upper Respiratory System These infections may be caused by several bacteria and viruses, often in combination.Most respiratory tract infections are self-limiting.H. influenzae type b can cause epiglottitis.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Streptococcal Pharyngitis (Strep Throat) GAS- Streptococcus pyogenesResistant to phagocytosisStreptokinaseslyse clotsStreptolysins are cytotoxicDiagnosis by indirect agglutination/ EIAFigure 24.3MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Streptococcal Pharyngitis (Strep Throat) group A beta-hemolytic streptococci- Streptococcus pyogenes.Symptoms of this infection are inflammation of the mucous membrane and fever; tonsillitis and otitis media may also occur.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Streptococcal Pharyngitis (Strep Throat) Rapid diagnosis is made by enzyme immunoassays.Penicillin is used to treat streptococcal pharyngitis.Immunity to streptococcal infections is type-specific.Strep throat is usually transmitted by droplets.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Scarlet FeverStreptococcus pyogenesPharyngitisErythrogenic toxin produced by lysogenizedS. pyogenesby a phage.Figure 24.4MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Scarlet Fever Strep throat, caused by an erythrogenic toxin-producing S. pyogenes, results in scarlet fever.starts general malaise and swelling of neckSymptoms include a red rash, high fever, and a SPOTTED STRABERRY like red, enlarged tongue.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

DiphtheriaCorynebacteriumdiphtheriae: Gram-positive rod pleomorphic club shapeMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

DiphtheriaClinical Start as sore throat and fever followed by general malaise and swelling of neckDiphtheria (leather) tough grayish membrane of fibrin, dead tissue, and bacteriaDiphtheria toxin produced by lysogenizedC. diphtheriae (highly virulent toxin)MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

DiphtheriaFigure 24.6MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Diphtheria MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie TalaveraVao day nghe bai nay di ban http://nhattruongquang.0catch.com

DiphtheriaA membrane can block the passage of air.Exotoxin inhibits protein synthesis, and heart, kidney, or nerve damage may result (fatal)minimal dissemination of the exotoxin in the bloodstream.Antitoxin - neutralize the toxinAntibiotics- Penicillin and Erythromycin can stop growth of the bacteria.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

DiphtheriaPrevented by DTaP and Td vaccine (Diphtheria toxoid)Cutaneous diphtheria: Infected skin wound leads to slow healing ulcerMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

A 15 y/o male patient have chief complaint of difficulty of breathing with associated throat pain, difficulty of swallowing and fever. Physical exam reveals inflamed pharyngeal area covered by grayish thick mucus that is adherent. Patient was noted to have an incomplete set of vaccination. Grams staining reveals gram positive bacilli with endospore.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Corynebacteria (Genus Corynebacterium)Aerobic or facultativelyanaerobic

Small, pleomorphic (club-shaped), gram-positive bacilli short chains (“V” or “Y” configurations) or in clumps resembling “Chinese letters”

Cells contain metachromaticgranules

Lipid-rich cell wall contains meso -diaminopimelicacidOTITIS MEDIAinfection of the middle ear, primarily in infants and young childrenthree manifestationsacute otitis media

otitis media with effusionA. Symptoms - fever, pain in the ear, dulled hearing.

Otitis MediaS. pneumoniae (35%)H. influenzae (20-30%)M. catarrhalis (10-15%)S. pyogenes (8-10%)S. aureus (1-2%)RSVAffects 85% of children before age 3, and estimated 8 million cases/ yearFigure 24.7MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Otitis MediaTreated with broad-spectrum antibiotics Amoxicillin Incidence of S. pneumoniae reduced by vaccineFigure 24.7MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Otitis Media Earache, or otitis media, can occur as a complication of nose and throat infections.Pus accumulation causes pressure on the eardrum causes inflammation and pain.Often in children because of shorter and more horizontal eustachian tubeMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

B. DIAGNOSIS – 1. clinical presentation of fever and pain, especially following an URT infection such as a cold 2. otoscopic examination to see inflammation and/or fluid (pus); also loss of mobility with air pressure

discomfort - pressure and blocked nasal passagesCommon coldRhinoviruses (50%)Coronaviruses (15-20%)MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

The Common Cold Any one of approximately 200 different viruses can cause the common cold; rhinoviruses cause about 50% of all colds.Immunity is based on the ration of Ig A antibodiesMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

The Common Cold Symptoms Sneezingnasal secretionscongestion.Sinus infections, lower respiratory tract infections, laryngitis, and otitis media can occur as complications of a cold.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

The Common Cold Colds are most often transmitted by indirect contact.Rhinoviruses grow best slightly below body temperature.The incidence of colds increases during cold weatherAntibodies are produced against the specific viruses.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Microbial Diseases of the Lower Respiratory SystemBacteria, viruses, and fungi causeBronchitisBronchiolitisPneumoniaMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Lower Respiratory SystemThe ciliary escalator keeps the lower respiratory system sterile.Figure 24.2MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Pertussis (Whooping Cough)Bordetellapertussis: Gram-negative coccobacillusCapsuleTracheal cytotoxin of cell wall damaged ciliated cellsPertussistoxin produces systemic diseasePrevented by DTaP vaccine (acellularPertussis cell fragments)Figure 24.8MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Epidemiology of Bordetellapertussis InfectionMan is only natural host; obligate parasites of man

Disease is highly communicable (highly infectious)

Children under one year at highest risk, but prevalence increasing in older children and adults Whooping coughInhalation of aerosolsAdhere to ciliated epithelial cells (FHA, Pili)Toxin productionDamage to mucosal cells(TCT, Ptx, Acase, LPS?)Act on neurons(Ptx, Acase, LPS)Paroxysmal cough

Whooping coughSymptomsSevere coughing, spasms, inspiratory whoop LymphocytosisStages of diseaseCatarrhal -> Paroxysmal -> ConvalescentSpread--highlycontagiousInhalation or direct contact with secretionUsually self-limitingNeurological sequelaeSecondary respiratory infectionsSecondary aspiration pneumoniaeleading cause of death

Pertussis (Whooping Cough)MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Pertussis (Whooping Cough).MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Clinical Progression of Pertussis,or deathInflammation of respiratory mucosal memb.Most infectious, but generally not yet diagnosed

Laboratory Culture, Prevention & Treatment of BordetellaNonmotile

Requires nicotinamide and charcoal, starch, blood, or albumin

Isolated on modified Bordet-Gengouagar

Treatmentwith erythromycinPertussis (Whooping Cough) Laboratory diagnosis is based on isolation of the bacteria on enrichment and selective media, followed by serological tests.Regular immunization for children has decreased the incidence of pertussis.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

SituationerLeading causes of death world wideUp to a half of world’s population infected, 95% in developing countries8 million people get TB every year(WHO fact sheet 2007)

Philippines ranks 4th for # of TB cases worldwide, highest # per head in SEA2/3 of Filipinos with TB(DOH, 2007)

Rex Karl S. Teoxon, R.N, M.D46PTBMycobacterium tubercle, acid fast bacilliAirborne/dropletsPott’s disease – thoracolumbarMilliary TB – kidney, liver, lungs

Rex Karl S. Teoxon, R.N, M.D47

MorphologyMycobacterium tuberculosisThin straight rods, 0.4 x 3 µmAcid-fast organisms

Mycobacterial cell wall componentsLipids (mycolic acids)ProteinsPolysaccharides

TB symptomsCough with two weeks or moreSputum expectorationFeverSignificant weight lossHemoptysisChest and/or back pains

Rex Karl S. Teoxon, R.N, M.D52SIGNS AND SYMPTOMSWt loss, night sweats, low fever, non productive to productive cough, anorexia, Pleural effusion and hypoxemia, cervical lymphadenopathy

TuberculosisMycobacterium tuberculosis: Acid-fast rod; transmitted from human to human.M. bovis: <1% U.S. cases, not transmitted from human to human.M. avium-intracellulare complex infects people with late stage HIV infection.Figure 24.9MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

TuberculosisMycobacterium tuberculosisAcid fast-lipid, waxSlow growth (nutrient permeability)Resist to detergent and common antibioticsA leading cause of death by infectious disease 50% population infected, 3m death/yrReemergence in 1980 (AIDS, homeless, immigrants)DiagnosePPD testChest X-raySputum smear (for acid-fast bacilli)Sputum culture

Slow, 13 hour generation time, takes weeks

BacteriophageRex Karl S. Teoxon, R.N, M.D56PPD – IDmacrophages in skin take up Ag and deliver it to T cells T cells move to skin site, release lymphokines activate macrophages and in 48-72 hrs, skin becomes indurated - > 10 mm is (+)

Rex Karl S. Teoxon, R.N, M.D57DIAGNOSISChest x ray - cavitary lesion Sputum exam Sputum culture

Stages of diseasePrimary infectionAsymptomatic to flu-like3-5% develop TBTubercle (granulomatous response)Reactivation (active TB) Years later, 10% experienceLRT disease (pneumonia)Disseminated miliary TBAlmost everywhereAIDS and antibiotic resistance

Stages of pathogenesisEncounter - respiratory dropletEntry - direct inhalation into LRT (ID=10)SPREAD - alveoli, but can spread throughout body seeding many tissuesMultiplicationGrows in phagosome of macrophageStrict aerobeVery slow in culture (24 hr doubling time)Evade defenses Inhibits phagolysosomal fusion

Tuberculosis Tuberculosis is caused by Mycobacterium tuberculosis.Large amounts of lipids in the cell wall account for the bacterium’s acid-fast characteristic as well as its resistance to dryingnd disinfectants.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Tuberculosis M. tuberculosis may be ingested by alveolar macrophages; if not killed, the bacteria reproduce in the macrophages.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Tuberculosis Lesions formed by M. tuberculosis are called tuberclesDead macrophages and bacteria form the caseous lesion that might calcify and appear in an X ray as a Ghon’s complex.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Tuberculosis Liquefaction of the caseous lesion results in a tuberculous cavity in which M. tuberculosis can grow.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Tuberculosis New foci of infection can develop when a caseous lesion ruptures and releases bacteria into blood or lymph vessels; this is called miliary tuberculosis.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

M. tuberculosisDamageHost response to bacteria (cell-mediated immunity)Glycolipids (Freund adjuvant)Spread to new hostsContagious by droplet, resistant to dryingVaccine - BCGCauses people to become PPD+, not very effectiveInfect AIDSTreatmentUnusual set of antibiotics (isoniazid, ethambutol, rifampin)High mutation rate

Tuberculosis Miliary tuberculosis is characterized by weight loss, coughing, and loss of vigor.Chemotherapy usually involves 3 or 4 drugs taken for at least 6 months; multidrug-resistant M. tuberculosis is becoming prevalent.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Tuberculosis Positive tuberculin skin test an active case of TBprior infectionvaccination immunity to the diseaseInduration and reddening at inoculation site within 48hours.Most accurate- Mantoux testMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Tuberculosis Laboratory diagnosis is based on the presence of acid-fast bacilli and isolation of the bacteria, which requires incubation (3-6weeks) of up to 8 weeks (Lowenstein-Jensen Agar)MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

PPD Tuberculosis Skin Test CriteriaPPD = Purified Protein Derivative from M. tuberculosis

Chest X-Ray of Patient with Active Pulmonary Tuberculosis

Tuberculosis Mycobacterium boviscauses bovine tuberculosis transmitted to humans by unpasteurized milk.affect the bones or lymphatic system.BCG vaccine -a live, avirulent culture of M. bovisM. avium-intracellulare complex infects patients in the late stages of HIVMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

TuberculosisTreatment of tuberculosis: Prolonged treatment with multiple antibiotics.Vaccines: BCG, live, avirulent M. bovis; not widely used in United States.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

TuberculosisFigure 24.12MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Rex Karl S. Teoxon, R.N, M.D78MANAGEMENTshort course – 6-9 months long course – 9-12 monthsDOTS- direct observe treatment short courseCase findingHome meds (members of the family)ReferralsFollow-up short course – 6-9 months long course – 9-12 months

Rex Karl S. Teoxon, R.N, M.D79MANAGEMENTFollow-up * 2 wks after medications – non communicable 3 successive (-) sputum - non communicablerifampicin - prophylactic

Rex Karl S. Teoxon, R.N, M.D80CATEGORIES OF TBcategory I (new PTB) - (+) sputumcategory II (relapse)category III (PTB case) - (-) sputum

Rex Karl S. Teoxon, R.N, M.D81TREATMENT:CATEGORY 1 - NEW PTB, (+) SPUTUMGIVE RIPE 2 MONTHS, MAINTENANCE OF RI 4 MONTHSCATEGORY 2 - PREVIOUSLY TREATED WITH RELAPSESGIVE RIPES 1ST 2 MONTHS, REPS 1 MONTH, MAINTENANCE RIE 5 MONTHSCATEGORY 3 - NEW PTB (-) SPUTUM FOR 3XGIVE RIP 2 MONTHS, MAINTENACE RI 2 MONTHS* IF RESISTANT TO DRUGS GIVE ADDITIONAL MONTH/S AS PRESCRIBED

Rex Karl S. Teoxon, R.N, M.D82MDT side effectsr-orange urinei-neuritis and hepatitisp-hyperuricemiae-impairment of visions-8th cranial nerve damage

AFB SMEAR REPORTING GUIDELINE, DOHNATIONAL TUBERCULOSIS CONTROL PROGRAM (2001)Emilio M. Ramirez, MD

National Tuberculosis Control Program (2001)prevent transmission of tubercle bacilli to a healthy person

Goal: Reduce TB mortality and prevalence through early case detection and treatmentTarget: identify at least 70% of new smear (+) cases, cure at least 85% TB patients discoveredStrategy: DOTS (directly observed treatment short course chemotheapy)

Sputum Collection Schedule forDIAGNOSIS

Ideal sputum specimen?MACROSCOPICYellowish

Cheesy materialWhen to collect another set of 3 sputum specimens?When the diagnosis for the sputum microscopy examination is doubtful.When the patient fails to complete his sputum collection within two weeks from the time of the previous collection.

Ideal sputum specimen?MICROSCOPICgreater than 25 wbc/LPO, 5 wbc/OIO

Presence of alveolar macrophage, dust cellsAFB STAINING

DIRECT SMEAR EXAMINATION(Flow Chart)SMEARING SPREADING DRYING FIXATIONSTAINING INITIAL STAINING HEATING WASHING DECOLORIZATION WASHING COUNTER-STAINING WASHING DRYINGMICROSCOPIC OBSERVATION RECORDING & REPORTING

DIRECT SMEAR PREPARATIONLABELING THE SLIDESWrite down the identification number of the sputum specimen on the end of a clean glass slide.

SMEARINGSPREADINGWith a coconut midrib, fish out one (1) loopful of purulent, solid particles of the sputum.Spread the sputum evenly on the slide, approximately 2 x 3 cm in size.

A Good SmearPoor/too thick Good Poor/too thin

SMEARINGDRYINGAllow the smear to dry completely at room temperature. Do not dry it under the sun or over the flame.Place used midribs in a bottle with alcohol and sand mixture or Lysol, or in a plastic containers and burn them later.

SMEARINGFIXATIONFix the smear by passing it through the flame of an alcohol lamp 2 to 3 times, about 2-3 seconds each. Heat the back of smeared surface of the slide. Never scorch the smear.

STAININGFIXATIONFix the smear by passing it through the flame of an alcohol lamp 2 to 3 times, about 2-3 seconds each. Heat the back of smeared surface of the slide. Never scorch the smear.

STAININGINITIAL STAININGArrange the slides on the staining bridge consecutively. Pour carbol fuchsin solution covering the whole surface of the slide.

STAININGHEATING OF THE SLIDEHeat the slide using an alcohol lamp or spirit cotton in a stick ‘till steam comes off from the stain. Do not boil and do not allow the stain to dry. Leave it for five minutes.

STAININGWASHING OF THE SLIDETilt the slide to drain off excess stain.Wash the staining solution off with a gentle stream of running water.

STAININGDECOLOURIZATIONTilt the slide to drain off excess rinse water.Cover the whole slide with 3% hydrochloric acid-ethanol and leave it until solution runs clear.

StainingWASHING OF THE SLIDEWash the slide with a gentle stream of running water.Tilt the slide to drain off excess rinse water.

StainingCOUNTERSTAININGPour 0.1% methylene blue to cover the whole surface of the smear and leave for 5-10 seconds.Tilt the slide to drain off excess methylene blue.

StainingWASHING AND DRYINGWash the slide with a gentle stream of running water.Tilt and place the slide on the slide rack to dry in the air. Don’t place under the sun to dry.

SMEAR READINGPROPER SCANNING Horizontal Scanning Vertical ScanningIMPROPER SCANNING Zigzag Scanning3 cm

AFB OBSERVATIONSingle/parallelformCoccoid formClump formScratches on the slide

MICROSCOPIC OBSERVATION OF AFB IN PROPERLY AND IMPROPERLY STAINED SMEARPROPER STAININGINSUFFICIENT HEATINGUNDERDECOLORIZEDINTENSELY COUNTERSTAINED

National Standard Reporting Scale (2001)

INTERPRETATION OF LAB RESULTSPOSITIVE - if all or at least two of the three specimens are positiveNEGATIVE - if all (3) specimens are negativeDOUBTFUL - if one of the three specimens is positive (sputum examination should be repeated)

Bacterial PneumoniasTypical pneumonia is caused by S. pneumoniae.Atypical pneumonias are caused by other microorganisms.Lobar pneumoniabronchopneumoniaMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

PneumoniasSign/ symptomsHigh feverDOBChest painProductive coughMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie TalaveraMortality within 30 days according to PSI risk class19

Pneumomoccal PneumoniaStreptococcus pneumoniae: Gram-positive encapsulated diplococciDiagnosis is by culturing bacteria.Penicillin Fluoroquinolones is drug of choice.Figure 24.13MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Pneumococcal pneumonia(Streptococcus pneumoniae)Gram-positive diplococcusEncapsulated (>80 serotypes)Susceptible populationElderlyPreviously illPhagocytic dysfunction (e.g., asplenic, sickle cell)Also cause meningitis, otitis mediaSensitive to optichin; autolysis by bile

Pneumococcal PneumoniaThe bacteria can be identified alpha-hemolysins, inhibition by optochin, bile solubility serological tests.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

120IdentificationNot optochin sensitiveoptochin sensitive

Pneumococcal Pneumonia Symptoms Feverbreathing difficultychest painrust-colored sputum.A vaccine consists of purified capsular material from 23 serotypes of S. pneumoniae.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Stages of pathogenesisEncounter - humans only, by respiratory dropletEntry - colonization of the oropharynx, aspiration into lung (pneumonia)Spread (extracellular)Pneumonia - blood culture can be positiveMeningitis - penetration of mucous membraneOtitis media- eustachian tube to middle earMultiplication Grows well in serous fluid in alveoli spaceEvade defensesCapsule--antiphagocyticsIgA protease

Haemophilus Influenzae PneumoniaGram-negative coccobacillusAlcoholism, poor nutrition, cancer, or diabetes are predisposing factors.Second-generation cephalosporinsMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Mycoplasmal Pneumonia Mycoplasmapneumoniae causes mycoplasmal pneumonia; it is an endemic disease.Young adults and childrenSymptoms persist for 3 weeks and longer (low fever, cough and headaches)PRIMARY ATYPICAL/ WALKING PNEUMONIAMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Mycoplasmal Pneumonia M. pneumoniae produces small “fried-egg” colonies after two weeks’ incubation on enriched media containing horse serum and yeast extract. Diagnosis is by PCR or serological tests.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Atypical (walking) pneumoniaMycoplasma pneumoniaLacks peptidoglycan-lactam resistantDisease primarily in young adultsEncounter - inhalation from humanEntry - restricted to mucosal surfaceTerminal adhesin protein (P1)Multiplication - require sterolsDamageInflammationDamage and desquamation of ciliated epitheliumTreatmentsErythromycin, doxycycline, tetracyline

Model for mycoplasma pathogenesis in the lungs

LegionellosisThe disease is caused by the aerobic gram-negative rod Legionellapneumophila.High fever 40.5C, cough and general pneumonia symptomsThe bacterium can grow in water, such as air-conditioning cooling towers, and then be disseminated in the air.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Legionnaire's disease/Pontiac FeverLegionella pneumophilaGram-negative rodStains irregularlySilver stainDiseasePontiac Fever - flu-like in anyone (1968) Fever muscular ache and cough(self limiting)Legionnaire's disease - pneumoniaPrimarily in middle aged to older men who heavy smoker and drinker or chronically ill1976 American Legion Convention in Philadelphia ( toll 182 cases/29 death)

LegionellosisThis pneumonia does not appear to be transmitted from person to person.Bacterial culture, FA tests, and DNA probes are used for laboratory diagnosis. Prevention : Copper Ionizing procedureTreatment : Erythromycin, some macrolides like AzithromycinMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Psittacosis (Ornithosis) Chlamydophilapsittaci – gram negative intracellular bacteria and is transmitted by contact with contaminated droppings and exudates of fowl.Elementary bodies allow the bacteria to survive outside a host.s/sx: fever, headache , chills, some with delirium and disorientationMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Psittacosis (Ornithosis) Commercial bird handlers are most susceptible to this disease.The bacteria are isolated in embryonated eggs, mice, or cell culture; identification is based on FA staining.Tx: TetracyclineMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Chlamydial Pneumonia Chlamydophilapneumoniae causes pneumonia; it is transmitted from person to person.Atherosclerosis-deposition of fats on arteriess/sx resemble mycoplasma pneumoniaTetracycline is used for treatment.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Q Fever Obligately parasitic, intracellular Coxiellaburnetii causes Q fever or X feverThe disease is usually transmitted to humans through unpasteurized milk or inhalation of aerosols in dairy barns, cattle tick bitesLaboratory diagnosis is made with the culture of bacteria in embryonated eggs or cell culture.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Q Fever Wide range of clinical symptoms60% asymptomatics/sx: High fever, muscle ache, headache and coughingHepatitis and endocarditis (persist for months)Tx: Doxycycline , ChloroquineMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Melioidosis Melioidosis, glanders disease (horses) caused by Burkholderiapseudomalleitransmitted by inhalation, ingestion, or through puncture wounds. Symptoms include pneumonia, sepsis, and encephalitis.Tx: CeftazidimeMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Diagnostic MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Viral Pneumonia A number of viruses can cause pneumonia as a complication of infections such as influenza.The etiologies are not usually identified in a clinical laboratory because of the difficulty in isolating and identifying viruses.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Respiratory Syncytial Virus (RSV) RSV is the most common cause of pneumonia in infants 2-6monthsLife threatening- txRibavirin and PalizumabCoughing, wheezing last more than a week, fever by bacterial infectionMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

InfluenzaHemagglutinin (H) spikes used for attachment to host cells.Neuraminidase (N) spikes used to release virus from cell.Figure 24.16MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

InfluenzaAntigenic shiftChanges in H and N spikesProbably due to genetic recombination between different strains infecting the same cellAntigenic driftMutations in genes encoding H or N spikesMay involve only 1 amino acid.Allows virus to avoid mucosal IgA antibodies.MICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Influenza SerotypesA: Causes most epidemics, H3N2, H1N1, H2N2B: Moderate, local outbreaks C: Mild diseaseMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

Influenza Deaths during epidemic - secondary bacterial infections.Multivalent vaccines for the elderly and other high-risk groups.Amantadine and rimantadine are effective prophylactic and curative drugsZanamivir and oseltamivirMICROPARA- RESPIRATORY INFECTIONby Dr Sonnie Talavera

152SARSCoronavirusSevere acute respiratory syndrome IP: 2-7 daysMOT: respiratory droplet/person to person contact

153RISK FACTORShistory of recent travel to China, Hong Kong, or Taiwan or close contact w/ ill persons with a hx of recent travel to such areas, ORIs employed in an occupation at particular risk for SARS exposure, i.e. healthcare worker with direct patient contact or a worker in a laboratory that contains live SARS, ORIs part of a cluster of cases of atypical pneumonia without an alternative diagnosis

154SIGNS AND SYMPTOMSfever, chills, rigors, myalgia, headache, diarrhea, sore throat, rhinorrhea2-7 days after onset of illness - shortness of breath and/or dry cough

155DIAGNOSISviral culturePCRserologic testing Mgmt: supportive

Respimicro [recovered]

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Respimicro [recovered]