MycoplasmasMycoplasmas and and ActinomycetesActinomycetes

Presented byPresented by

فطاني. مان جي محمد احمد آصف فطاني. د مان جي محمد احمد آصف د) عبد�العزيز ) الملك جامعة والجراحة الطب (بكاالوريوس عبد�العزيز ) الملك جامعة والجراحة الطب بكاالوريوس

) مانشستر ) جامعة والجزيئية الطبية الدقيقة الكائنات (ماجستير مانشستر ) جامعة والجزيئية الطبية الدقيقة الكائنات ماجستير) بريطانيا ) – مانشستر جامعة الطبية الدقيقة الكائنات (دكتوراه بريطانيا ) – مانشستر جامعة الطبية الدقيقة الكائنات دكتوراه

Dr Asif Jiman-Fatani, MB ChB, MSc, PhD (UK)Dr Asif Jiman-Fatani, MB ChB, MSc, PhD (UK)Assistant Professor in Medical Microbiology,Assistant Professor in Medical Microbiology,

Faculty of Medicine, King Abdulaziz UniversityFaculty of Medicine, King Abdulaziz University

Consultant MicrobiologistConsultant MicrobiologistHead, Clinical Microbiology LaboratoriesHead, Clinical Microbiology Laboratories

King Abdulaziz University HospitalKing Abdulaziz University Hospital

MYCOPLASMASMYCOPLASMASCharacteristicsCharacteristics

Lacking cell wallLacking cell wall Resistant to antibacterials that inhibit cell wall synthesisResistant to antibacterials that inhibit cell wall synthesis Gram’s stain : Not usefulGram’s stain : Not useful PleomorphicPleomorphic Cannot be classified as either cocci or bacilliCannot be classified as either cocci or bacilli

Enclosed in a plasma membraneEnclosed in a plasma membrane Lipid bilayer membrane containing sterolsLipid bilayer membrane containing sterols

Smallest free-living organismsSmallest free-living organisms Pass through bacteriologic filtersPass through bacteriologic filters

Can be cultured in vitro.Can be cultured in vitro.

MYCOPLASMASMYCOPLASMAS

Mycoplasma pneumoniaeMycoplasma pneumoniae →→ Atypical Pneumonia

Mycoplasma hominis → → STI: Non-gonococcal Urethritis, Cervicitis, PID

Ureaplasma urealyticum → → STI: Non-gonococcal Urethritis, Cervicitis, PID

Mycoplasma pneumoniae Mycoplasma pneumoniae )Eaton’s reagent()Eaton’s reagent(

Habitat and TransmissionHabitat and Transmission

Habitat is the human respiratory tract.Habitat is the human respiratory tract.

TransmissionTransmission : Respiratory droplets. : Respiratory droplets.

Mycoplasma pneumoniaeMycoplasma pneumoniaePathogenesisPathogenesis

P1 adhesion proteinP1 adhesion protein M. pneumoniaeM. pneumoniae binds to respiratory ciliated epithelium binds to respiratory ciliated epithelium Adherence results in ciliostasis & cell destruction Adherence results in ciliostasis & cell destruction →→ reduced reduced

ciliated clearanceciliated clearance Bacteria then gain access to the lower respiratory tractBacteria then gain access to the lower respiratory tract

Produces Produces hydrogen peroxidehydrogen peroxide : may damage the : may damage the respiratory tract.respiratory tract.

No exotoxins produced.No exotoxins produced. No endotoxin because there is no cell wall.No endotoxin because there is no cell wall.

Mycoplasma pneumoniaeMycoplasma pneumoniaeDiseasesDiseases

AtypicalAtypical pneumonia pneumonia :: Clinical Features: Fever – Clinical Features: Fever – DryDry cough “or scantily cough “or scantily

productive cough”productive cough” Walking pneumoniaWalking pneumonia Complications: Mild hemolytic anaemiaComplications: Mild hemolytic anaemia

Upper Respiratory Diseases :Upper Respiratory Diseases : Otitis MediaOtitis Media PharyngitisPharyngitis TracheobronchitisTracheobronchitis

Mycoplasma pneumoniaeMycoplasma pneumoniaeLaboratory DiagnosisLaboratory Diagnosis

Specimens: but scanty sputumSpecimens: but scanty sputum Gram stain : not useful.Gram stain : not useful.

Culture: on Culture: on special bacteriologicspecial bacteriologic media. Takes at least 10 days to grow )too media. Takes at least 10 days to grow )too long to be clinically useful(.long to be clinically useful(. Colonie: Fried egg appearanceColonie: Fried egg appearance

SerologySerology A cold-agglutinin titer of 1:128 or higher is indicative of recent A cold-agglutinin titer of 1:128 or higher is indicative of recent

infectioninfection Cold agglutinin: IgM autoantibodies against red blood cells that Cold agglutinin: IgM autoantibodies against red blood cells that

agglutinate these cells at 4 °C but not at 37 °C agglutinate these cells at 4 °C but not at 37 °C

Complement fixation test for antibodies to Complement fixation test for antibodies to Mycoplasma pneumoniaeMycoplasma pneumoniae is more specific.is more specific.

PCRPCR

Note Note : Diagnosis relies on clinical findings: Diagnosis relies on clinical findings

Mycoplasma pneumoniaeMycoplasma pneumoniaeTreatmentTreatment Erythromycin or …Erythromycin or … Tetracycline.Tetracycline.

PreventionPrevention No vaccine or drug is availableNo vaccine or drug is available

Genital MycoplasmasGenital Mycoplasmas

Mycoplasma hominis → → STD: Non-gonococcal Urethritis, Cervicitis, PID

Ureaplasma urealyticum → → STD: Non-gonococcal Urethritis, Cervicitis, PID

ActinomycetesActinomycetes

ActinomycetesActinomycetes Gram positive bacteriaGram positive bacteria

Filamentous branching bacilliFilamentous branching bacilli Superficially resemble fungi on morphologic groundsSuperficially resemble fungi on morphologic grounds

They are prokaryotesThey are prokaryotes

Has bacterial sizeHas bacterial size

ActinomycetesActinomycetes

Few are pathogenic to human, the most Few are pathogenic to human, the most important are :important are : Actinomyces israeliiActinomyces israelii Nocardia astroidesNocardia astroides

ACTINOMYCETESACTINOMYCETES

Actinomyces Actinomyces israeliiisraelii

Gram-positive filamentous branching bacilliGram-positive filamentous branching bacilli AnaerobicAnaerobic Grows slowlyGrows slowly

Actinomyces israeliiActinomyces israelii Habitat and TransmissionHabitat and Transmission

Habitat :Habitat : Found as scanty normal commensal in the: Found as scanty normal commensal in the: Mouth, especially anaerobic crevices around the teethMouth, especially anaerobic crevices around the teeth ColonColon VaginaVagina

Disease begins when these normal flora enter adjacent Disease begins when these normal flora enter adjacent sterile tissue e.g, by trauma, surgerysterile tissue e.g, by trauma, surgery

TransmissionTransmission into tissues occurs during : into tissues occurs during : Dental extraction - Poor dental hygieneDental extraction - Poor dental hygiene Trauma )mouth – uterus(Trauma )mouth – uterus( Organism also aspirated into lungs, causing thoracic actinomycosis.Organism also aspirated into lungs, causing thoracic actinomycosis.

Actinomyces israeliiActinomyces israeliiPathogenesisPathogenesis

Infections occur in both :Infections occur in both : Normal hostsNormal hosts Immunocompromised patientsImmunocompromised patients

No toxins or virulence factors known.No toxins or virulence factors known.

Organism forms sinus tracts that open onto skin and contain Organism forms sinus tracts that open onto skin and contain yellow “yellow “sulfur granulessulfur granules”” Sulfur granules : are made up of large masses of Sulfur granules : are made up of large masses of

organisms microcolonies of filamentous bacteriaorganisms microcolonies of filamentous bacteria

Actinomyces israeliiActinomyces israelii DiseaseDisease

Actinomycosis Actinomycosis )abscesses with draining sinus tracts()abscesses with draining sinus tracts( Chronic suppurative abscessChronic suppurative abscess The lesion )Mycetoma( :The lesion )Mycetoma( :

Begins as a hard red swellingBegins as a hard red swelling Ddevelops slowly, becomes filled with pusDdevelops slowly, becomes filled with pus Draining with sinus formationDraining with sinus formation

Sites:Sites: Oral-facial abscesses )> 50% of cases(Oral-facial abscesses )> 50% of cases(

Often associated with trauma or dental extractionOften associated with trauma or dental extraction Abdominal infections:Abdominal infections:

Abscess. Many after appendicitisAbscess. Many after appendicitis Uterine infection :Uterine infection :

Associated with intrauterine contraceptive devicesAssociated with intrauterine contraceptive devices Chest infectionChest infection Invasive infections in immunocompromised patientsInvasive infections in immunocompromised patients

Actinomyces israeliiActinomyces israelii Laboratory DiagnosisLaboratory Diagnosis

Specimen:Specimen: Pus Pus Filaments may aggregate to form visible granules “Sulphur Filaments may aggregate to form visible granules “Sulphur

granules” in pus: Yellowish particlesgranules” in pus: Yellowish particles No sulphurNo sulphur

Microscopy:Microscopy: Sulfur Granules :Sulfur Granules : Gram-positive filamentous, branching rods Gram-positive filamentous, branching rods

Culture:Culture: AnaerobicAnaerobic culture on blood agar plate )10 days( culture on blood agar plate )10 days( Molar teeth coloniesMolar teeth colonies

No serologic tests.No serologic tests.

Actinomyces israeliiActinomyces israeliiTreatmentTreatment

PenicillinPenicillin For up to 3-12 monthsFor up to 3-12 months

Tetracyclin or ClindamycinTetracyclin or Clindamycin For penicillin-allergic patientsFor penicillin-allergic patients

Surgical drainageSurgical drainage

PreventionPrevention Good oral hygieneGood oral hygiene Prophylactic antibiotics in association with GIT or oral trauma Prophylactic antibiotics in association with GIT or oral trauma

or surgeryor surgery No vaccine is available.No vaccine is available.

ACTINOMYCETESACTINOMYCETES

Nocardia asteroidesNocardia asteroides

Nocardia asteroidesNocardia asteroidesDiseaseDisease

Nocardiosis (especially lung and brain abscesses).Nocardiosis (especially lung and brain abscesses).

Nocardia asteroidesNocardia asteroidesCharacteristicsCharacteristics

Gram positive filamentous, branching rods.Gram positive filamentous, branching rods.

AerobicAerobic

Acid-fast (weakly)Acid-fast (weakly)

Nocardia asteroidesNocardia asteroides Habitat and TransmissionHabitat and Transmission

Habitat is the soil.Habitat is the soil.

Transmission :Transmission : Airborne particles, which are inhaled into the lungsAirborne particles, which are inhaled into the lungs Implantation : by contamination of skin woundsImplantation : by contamination of skin wounds

Nocardia asteroidesNocardia asteroidesPathogenesisPathogenesis

Predisposing Factors:Predisposing Factors: ImmunosuppressionImmunosuppression HIVHIV CancerCancer

No toxins or virulence factors known.No toxins or virulence factors known.

Nocardia asteroidesNocardia asteroidesDiseasesDiseases

Diseases:Diseases: Abscesses in: Abscesses in: LungLung BrainBrain KidneyKidney

Nocardia asteroidesNocardia asteroidesLaboratory DiagnosisLaboratory Diagnosis

Specimen :Specimen : Pus Pus

Microscopy :Microscopy : Gram-stained smear : Gram positive filamentous, branching rodsGram-stained smear : Gram positive filamentous, branching rods Ziehl-Neelsen stain )modified( : weakly AFB )branching(Ziehl-Neelsen stain )modified( : weakly AFB )branching(

Culture :Culture : Aerobic culture on blood agar plate.Aerobic culture on blood agar plate.

No serologic tests.No serologic tests.

Nocardia asteroidesNocardia asteroidesTreatmentTreatment

SulfonamidesSulfonamides Long durationLong duration Nocardia is resistant to penicillinNocardia is resistant to penicillin

PreventionPrevention No vaccine is available.No vaccine is available.

Differences between Differences between Actinomyces israeliiActinomyces israelii & & Nocardia astroidesNocardia astroides

Actinomyces israeliiActinomyces israeliiNocardia astroidesNocardia astroides

Growth Growth AtmosphereAtmosphere

AnaerobicAnaerobicAerobicAerobic

HabitatHabitatMouth, Colon, VaginaMouth, Colon, VaginaSoilSoil

TransmissionTransmissionTrauma (Tooth Trauma (Tooth extraction, Jaw fracture, extraction, Jaw fracture, Intrauterine Contr. Dev.)Intrauterine Contr. Dev.)

InhalationInhalation or or implantationimplantation

Sulfur granulesSulfur granulesYesYesNoNo

Acid-FastnessAcid-FastnessNoNoYes (weakly acid-fastYes (weakly acid-fast((

DiseaseDiseaseActinomycosis Actinomycosis (abscess with draining (abscess with draining sinuses) Cervicofacial, sinuses) Cervicofacial, Thorasic, Abd, PelvicThorasic, Abd, Pelvic

Nocardiosis (abscess in Nocardiosis (abscess in brain & kidneys in brain & kidneys in immunodeficient patients immunodeficient patients – Pneumonia)– Pneumonia)

TreatmentTreatmentPenicillinPenicillinSulfonamidesSulfonamides