Chlamydia
- 2. Family:Family: ChlamydiaceaeChlamydiaceae Genus:Genus: ChlamydiaChlamydia – C. trachomatisC. trachomatis Urogenital infections, Trachoma,Urogenital infections, Trachoma, Conjunctivitis, Pneumonia,Conjunctivitis, Pneumonia, Lymphogranuloma venerium (LGV)Lymphogranuloma venerium (LGV) – C. psittaciC. psittaci Pneumonia (Psittacosis)Pneumonia (Psittacosis) – C. pneumoniaeC. pneumoniae Bronchitis, sinusitis,Bronchitis, sinusitis, PneumoniaPneumonia ?? AtherosclerosisAtherosclerosis
- 3. Chlamydia-Chlamydia- MicrobiologyMicrobiology Small obligate intracellular parasitesSmall obligate intracellular parasites Contain DNA, RNA and ribosomesContain DNA, RNA and ribosomes Gram Negative cell wallGram Negative cell wall – Cell wall not well characterizedCell wall not well characterized – Inner and outer membraneInner and outer membrane – LPS but no peptidoglycanLPS but no peptidoglycan Dependant on energy moleculesDependant on energy molecules – Can’t make ATPCan’t make ATP
- 4. Physiology and StructurePhysiology and Structure Two morphological formsTwo morphological forms – Elementary bodyElementary body – Reticulate bodyReticulate body Elementary bodies (EB)Elementary bodies (EB) – Small (0.3 - 0.4 µm),Small (0.3 - 0.4 µm), ExtracellularExtracellular – Rigid outer membrane, ResistantRigid outer membrane, Resistant – Non-replicating, non-metabolically activeNon-replicating, non-metabolically active – InfectiousInfectious Bind to columnar epithelial cells / MacrophagesBind to columnar epithelial cells / Macrophages
- 5. Physiology and StructurePhysiology and Structure Reticulate bodies (RB)Reticulate bodies (RB) – Larger (0.8 - 1 µm)Larger (0.8 - 1 µm) – IntracellularIntracellular – Fragile membraneFragile membrane – Metabolically activeMetabolically active – ReplicatingReplicating – Non-infectiousNon-infectious
- 6. Developmental Cycle ofDevelopmental Cycle of ChlamydiaChlamydia EB bind to host cellsEB bind to host cells – Epithelial cellEpithelial cell – MacrophageMacrophage InternalizationInternalization – EndocytosisEndocytosis – PhagocytosisPhagocytosis Inhibition of phagosome-Inhibition of phagosome- lysosome fusionlysosome fusion Reorganization into RBReorganization into RB Growth of RB by binaryGrowth of RB by binary fissionfission
- 7. Developmental Cycle ofDevelopmental Cycle of ChlamydiaChlamydia Reorganization into EBReorganization into EB Inclusion bodiesInclusion bodies Release of EBRelease of EB – LysisLysis --C. psittaciC. psittaci – ExtrusionExtrusion -- C. trachomaC. trachoma andand C. pneumoniaeC. pneumoniae
- 8. Chlamydia trachomatisChlamydia trachomatis TrachomaTrachoma Inclusion conjunctivitisInclusion conjunctivitis Pneumonia in infantsPneumonia in infants Urogenital infectionsUrogenital infections Reiter’s SyndromeReiter’s Syndrome Lymphogranuloma venerium (Lymphogranuloma venerium (LGVLGV))
- 9. C. trachomatisC. trachomatis BiovarsBiovars - biological variants- biological variants – TrachomaTrachoma – LGVLGV SerovarsSerovars - serological variants- serological variants – Major outer membrane proteinsMajor outer membrane proteins – A through LA through L
- 10. C.C. trachomatis - Serovarstrachomatis - Serovars TRIC agents
- 11. Pathogenesis andPathogenesis and Immunity (Immunity (C.trachomatis)C.trachomatis) Infects epithelial cells / MacrophagesInfects epithelial cells / Macrophages Down regulation of Class I MHCDown regulation of Class I MHC Infiltration of PMNs and lymphocytesInfiltration of PMNs and lymphocytes Lymphoid follicle formationLymphoid follicle formation FibrosisFibrosis Disease results from destruction of cellsDisease results from destruction of cells and host immune responseand host immune response No long lasting immunity; reinfectionNo long lasting immunity; reinfection results in inflammatory responseresults in inflammatory response
- 12. C. trachomatisC. trachomatis - Epidemiology- Epidemiology TrachomaTrachoma – WorldwideWorldwide – Poverty and overcrowdingPoverty and overcrowding – Endemic in Africa, Middle East, India, SE AsiaEndemic in Africa, Middle East, India, SE Asia – Infection of childrenInfection of children – TransmissionTransmission: droplets, hands, contaminated: droplets, hands, contaminated clothing, flies, contaminated birth canalclothing, flies, contaminated birth canal
- 13. C. trachomatisC. trachomatis - Epidemiology- Epidemiology Genital tract infectionsGenital tract infections – Biovar: TrachomaBiovar: Trachoma STDSTD 50 million new cases/year worldwide50 million new cases/year worldwide – Biovar: LGVBiovar: LGV Prevalent in Africa, Asia and South AmericaPrevalent in Africa, Asia and South America
- 14. TrachomaTrachoma Chronic or repeated infectionChronic or repeated infection – Follicle formation on conjunctivaFollicle formation on conjunctiva – Scarring of the conjunctivaScarring of the conjunctiva
- 15. TrachomaTrachoma Eyelids turn in and abrade corneaEyelids turn in and abrade cornea – UlcerationUlceration – ScarringScarring – Blood vessel formationBlood vessel formation
- 16. TrachomaTrachoma Flow of tears impededFlow of tears impeded – Secondary infectionsSecondary infections
- 17. TrachomaTrachoma
- 19. Inclusion ConjunctivitisInclusion Conjunctivitis ((C.trachomatisC.trachomatis)) Associated with genital chlamydiaAssociated with genital chlamydia Mucopurulent dischargeMucopurulent discharge Corneal infiltrates, vascularization andCorneal infiltrates, vascularization and scarring can occurscarring can occur In neonates infection results fromIn neonates infection results from infected birth canalinfected birth canal – Apparent 5-12 days after birthApparent 5-12 days after birth – Ear infection and rhinitis often accompanyEar infection and rhinitis often accompany ocular diseaseocular disease
- 20. Infant PneumoniaInfant Pneumonia ((C.trachomatisC.trachomatis biovar: trachoma)biovar: trachoma) Associated with genital chlamydiaAssociated with genital chlamydia Infection arises from contaminated birthInfection arises from contaminated birth canalcanal Wheezing cough and pneumonia but noWheezing cough and pneumonia but no feverfever Often preceded by conjunctivitisOften preceded by conjunctivitis
- 21. Urogenital InfectionsUrogenital Infections ((C.trachomatisC.trachomatis)) FemalesFemales – Asymptomatic (80%)Asymptomatic (80%) – Cervicits, urethritis and salpingitisCervicits, urethritis and salpingitis – Postpartum feverPostpartum fever – Increased rateIncreased rate Premature deliveryPremature delivery Ectopic pregnancyEctopic pregnancy
- 22. Urogenital InfectionsUrogenital Infections ((C.trachomatisC.trachomatis)) MalesMales – Symptomatic (75%)Symptomatic (75%) – Urethritis, dysuria and pyuriaUrethritis, dysuria and pyuria – Cause ofCause of nongonococcal urethritisnongonococcal urethritis (35 - 50%)(35 - 50%) – Common cause ofCommon cause of postgonococcal urethritispostgonococcal urethritis
- 23. Reiter’s SyndromeReiter’s Syndrome Conjunctivitis, polyarthritis and genital orConjunctivitis, polyarthritis and genital or gastrointestinal inflammationgastrointestinal inflammation Associated with HLA-B27Associated with HLA-B27 50 - 65 % have50 - 65 % have C. trachomatisC. trachomatis infectioninfection 80% have antibodies to80% have antibodies to C. trachomatisC. trachomatis
- 24. Lymphogranuloma VenereumLymphogranuloma Venereum(LGV(LGV)) C. trachomatisC. trachomatis Sexually TransmittedSexually Transmitted First stageFirst stage – Small painless vesicular lesion at infection siteSmall painless vesicular lesion at infection site – Fever, headache and myalgiaFever, headache and myalgia Second stageSecond stage – Inflammation of draining lymph nodesInflammation of draining lymph nodes – Fever, headache and myalgiaFever, headache and myalgia – Buboes (rupture and drain)Buboes (rupture and drain) – ProctitisProctitis – Ulcers or ElephantiasisUlcers or Elephantiasis
- 25. Patient with LGVPatient with LGV Bilateral inguinal buboesBilateral inguinal buboes (arrows)(arrows)
- 26. C. trachomatisC. trachomatis - Diagnosis- Diagnosis CytologyCytology – IntracellularIntracellular Inclusion bodyInclusion body CultureCulture – HeLa, Mc CoyHeLa, Mc Coy cell linecell line – Yolk Sac ChickYolk Sac Chick embryoembryo – Iodine stainingIodine staining inclusionsinclusions Iodine-stained inclusion bodies
- 27. C.C. trachomatis - Diagnosistrachomatis - Diagnosis Antigen detectionAntigen detection (ELISA or IF)(ELISA or IF) – Group specific LPSGroup specific LPS – Strain specific outer membrane proteinsStrain specific outer membrane proteins SerologySerology – CF, ELISA, MIFCF, ELISA, MIF – Can’t distinguish between current or pastCan’t distinguish between current or past infectioninfection – Detection of high titer IgM antibodies can beDetection of high titer IgM antibodies can be helpfulhelpful Nucleic acid probesNucleic acid probes – Several kits availableSeveral kits available – May eventually replace cultureMay eventually replace culture
- 28. C. trachomatisC. trachomatis - Treatment and- Treatment and PreventionPrevention Tetracycline, erythromycin andTetracycline, erythromycin and sulfonamidessulfonamides Vaccines are of little valueVaccines are of little value Treatment coupled with improvedTreatment coupled with improved sanitationsanitation Safe sexual practicesSafe sexual practices Treatment of patients and their sexualTreatment of patients and their sexual partnerspartners
- 29. Chlamydophilia (Chlamydia)Chlamydophilia (Chlamydia) psittacipsittaci Psittacosis (Parrot fever)Psittacosis (Parrot fever) OrnithosisOrnithosis
- 30. Pathogenesis -Pathogenesis - C. psittaciC. psittaci Inhalation of organisms in bird droppingsInhalation of organisms in bird droppings – Person to person transmission is rarePerson to person transmission is rare Hematogenous spread to spleen and liverHematogenous spread to spleen and liver – Local necrosis of tissueLocal necrosis of tissue Hematogenous spread to lungs and otherHematogenous spread to lungs and other organsorgans Lymphocytic inflammatory responseLymphocytic inflammatory response – Edema, infiltration of macrophages, necrosis andEdema, infiltration of macrophages, necrosis and occasionally hemorrhageoccasionally hemorrhage – Mucus plugs may develop in alveoliMucus plugs may develop in alveoli Cyanosis and anoxiaCyanosis and anoxia
- 31. Epidemiology -Epidemiology - C. psittaciC. psittaci Organisms present in birds (symptomaticOrganisms present in birds (symptomatic or asymptomatic)or asymptomatic) – Tissue, feces, feathersTissue, feces, feathers Primarily an occupational diseasePrimarily an occupational disease – Veterinarians, poultry workers, zoo keepers,Veterinarians, poultry workers, zoo keepers, pet shop workerspet shop workers
- 32. OrnithosisOrnithosis Uncomplicated InfectionUncomplicated Infection Incubation periodIncubation period – 1-2 weeks1-2 weeks Fever, chills, headache, nonproductiveFever, chills, headache, nonproductive cough, mild pneumonitiscough, mild pneumonitis RecoveryRecovery – 5-6 weeks5-6 weeks
- 33. OrnithosisOrnithosis Complicated InfectionComplicated Infection Incubation periodIncubation period – 1-2 weeks1-2 weeks Fever, chills, headache, nonproductive cough, mentalFever, chills, headache, nonproductive cough, mental confusion, pneumonitis, cyanosis, jaundiceconfusion, pneumonitis, cyanosis, jaundice Prolonged RecoveryProlonged Recovery – 7-8 weeks7-8 weeks
- 34. Laboratory Diagnosis -Laboratory Diagnosis - C. psittaciC. psittaci Serology (Complement fixation test)Serology (Complement fixation test) – Fourfold rise in titerFourfold rise in titer
- 35. Treatment and Prevention -Treatment and Prevention - C. psittaciC. psittaci Tetracycline or erythromycinTetracycline or erythromycin Quarantine of imported birdsQuarantine of imported birds Control of bird infectionControl of bird infection – Antibiotic supplementation of foodAntibiotic supplementation of food
- 36. Chlamydophilia (Chlamydia)Chlamydophilia (Chlamydia) pneumoniaepneumoniae TWAR agentTWAR agent – Taiwan (TW-183) and acute respiratoryTaiwan (TW-183) and acute respiratory isolate (AR-39)isolate (AR-39) Atypical pneumoniaAtypical pneumonia Atherosclerosis ?Atherosclerosis ?
- 37. Pathogenesis -Pathogenesis - C. pneumoniaeC. pneumoniae Person to person spreadPerson to person spread – Respiratory dropletsRespiratory droplets Bronchitis, sinusitis and pneumoniaBronchitis, sinusitis and pneumonia
- 38. Epidemiology -Epidemiology - C. pneumoniaeC. pneumoniae Common infection (200,000 - 300,000 cases perCommon infection (200,000 - 300,000 cases per year)year) Primarily in adultsPrimarily in adults Most infections are asymptomaticMost infections are asymptomatic Associated with crowded conditionsAssociated with crowded conditions – Schools, military basesSchools, military bases etc.etc. Association with atherosclerosisAssociation with atherosclerosis – Organisms in diseased arteriesOrganisms in diseased arteries – AntibodiesAntibodies
- 39. Clinical Syndrome -Clinical Syndrome - C. pneumoniaeC. pneumoniae Mild or asymptomatic diseaseMild or asymptomatic disease Pharyngitis, bronchitis, persistent coughPharyngitis, bronchitis, persistent cough and malaiseand malaise Pneumonia may developPneumonia may develop – Usually a single lobeUsually a single lobe
- 40. Laboratory Diagnosis -Laboratory Diagnosis - C. pneumoniaeC. pneumoniae SerologySerology – Fourfold rise in titerFourfold rise in titer
- 41. Treatment and Prevention -Treatment and Prevention - C.C. pneumoniaepneumoniae Tetracycline or erythromycinTetracycline or erythromycin Difficult to prevent transmissionDifficult to prevent transmission No vaccineNo vaccine