Mycoplasma

mycoplasma

1. MycoplasmaMycoplasma
Shilpa.KShilpa.K
Microbiology TutorMicrobiology Tutor
AIMSRCAIMSRC

2. MycoplasmataceaeMycoplasmataceae
Two genera Two genera
–Mycoplasma Mycoplasma
–UreaplasmaUreaplasma
Smallest free living bacteriaSmallest free living bacteria
Do not have a cell wallDo not have a cell wall
–Resistant to cell wall acting antibioticsResistant to cell wall acting antibiotics
Cell membrane contains sterolsCell membrane contains sterols
Slow growing & Facultative anaerobeSlow growing & Facultative anaerobe
Do not stain by ordinary methodsDo not stain by ordinary methods
Morphology : Highly pleomorhicMorphology : Highly pleomorhic

3. Mycoplasma Mycoplasma (Scanning EM)(Scanning EM)

4. Important human Important human
pathogenspathogens
Mycoplasma pneumoniaeMycoplasma pneumoniae
–Eaton’s agentEaton’s agent
–Pleuropneumonia like organism (PPLO)Pleuropneumonia like organism (PPLO)
Mycoplasma hominisMycoplasma hominis
Mycoplasma genitaliumMycoplasma genitalium
Ureaplasma urealyticumUreaplasma urealyticum

5. Organism Disease
M. pneumoniaeUpper respiratory tract disease,
tracheobronchitis, atypical
pneumonia, (chronic asthma??)
M. hominis Pyleonephritis, pelvic
inflammatory disease,
postpartum fever
M. genitaliumNongonococcal urethritis
U. urealyticumNongonococcal urethritis,
(pneumonia and chronic lung
disease in premature infants??)
Diseases Caused by Mycoplasma

6. Mycoplasma Mycoplasma
pneumoniaepneumoniae
Strict human pathogenStrict human pathogen
Attaches by P1 pili to ciliary base on Attaches by P1 pili to ciliary base on
epithelial cellepithelial cell
Disease spreads by inhalation of Disease spreads by inhalation of
aerosolsaerosols
Spreads among close contactsSpreads among close contacts
Disease seen worldwideDisease seen worldwide

7. Mycoplasma Mycoplasma
pneumoniaepneumoniae
DiseasesDiseases
–Upper respiratory tract diseasesUpper respiratory tract diseases
–TracheobronchitisTracheobronchitis
–Primary atypical pneumoniaPrimary atypical pneumonia
–Complications Complications
neurological abnormalities, neurological abnormalities,
myo/pericarditismyo/pericarditis
hemolytic anemiahemolytic anemia

8. Atypical pneumoniaAtypical pneumonia
M. pneumoniaeM. pneumoniae
Incubation - 2-3 weeksIncubation - 2-3 weeks
Fever, headache and malaiseFever, headache and malaise
Persistent non-productive coughPersistent non-productive cough
Respiratory symptomsRespiratory symptoms
–Radiological signs precede symptomsRadiological signs precede symptoms
Organisms persist Organisms persist
Slow resolutionSlow resolution
Rarely fatalRarely fatal

9. LAB Diagnosis- LAB Diagnosis- M M
pneuminiaepneuminiae
SpecimenSpecimen
Respiratory secretionsRespiratory secretions
SerumSerum

10. Laboratory Diagnosis - Laboratory Diagnosis - M. M.
pneumoniaepneumoniae
MicroscopyMicroscopy
–Difficult to stainDifficult to stain
–Can help eliminate other organismsCan help eliminate other organisms
Culture (Culture (definitive diagnosisdefinitive diagnosis))
–Sputum or throat washingsSputum or throat washings
–Special transport medium neededSpecial transport medium needed
High index of suspicion - High index of suspicion - M. pneumoniaeM. pneumoniae
–May take 2-3 weeksMay take 2-3 weeks

11. Culture media usedCulture media used
PPLO broth and agarPPLO broth and agar
Serum is necessary for growthSerum is necessary for growth
In broth, growth indicated by pH change In broth, growth indicated by pH change
due to carbohydrate metabolismdue to carbohydrate metabolism
Colonies best seen under microscope – Colonies best seen under microscope –
Diene’s staining techniqueDiene’s staining technique

12. M pneumoniae coloniesM pneumoniae colonies

13. SerologySerology
Very useful as culture is technically Very useful as culture is technically
demandingdemanding
Specific and nonspecific serological testsSpecific and nonspecific serological tests
Specific testsSpecific tests
–Complement Fixation, ELISA, IFAComplement Fixation, ELISA, IFA
Non specific testsNon specific tests
–Streptococcus MG agglutination test Streptococcus MG agglutination test
–Cold agglutinin test with human O RBCs. Cold agglutinin test with human O RBCs.
Significant titer is > 1:128.Significant titer is > 1:128.

14. Treatment - Treatment - M. pneumoniaeM. pneumoniae
Treatment Treatment
–Tetracycline or erythromycinTetracycline or erythromycin
–Can’t use cell wall synthesis inhibitorsCan’t use cell wall synthesis inhibitors

15. Genital mycoplasmaGenital mycoplasma
M.hominisM.hominis
M.genitaliumM.genitalium
Ureaplasma urealyticumUreaplasma urealyticum

16. Organism Disease
M. pneumoniaeUpper respiratory tract disease,
tracheobronchitis, atypical
pneumonia, (chronic asthma??)
M. hominis Pyleonephritis, pelvic
inflammatory disease,
postpartum fever
M. genitaliumNongonococcal urethritis
U. urealyticumNongonococcal urethritis,
(pneumonia and chronic lung
disease in premature infants??)
Diseases Caused by Mycoplasma

17. M. hominisM. hominis, , M. genitaliumM. genitalium
and and
U. urealyticumU. urealyticum
Laboratory diagnosisLaboratory diagnosis
–Culture (except Culture (except M. genitaliumM. genitalium))
–Fried egg appearence of colonies on Fried egg appearence of colonies on
PPLO agarPPLO agar

18. Mycoplams spp Mycoplams spp
-Colonies-Colonies

19. Differentiation of SpeciesDifferentiation of Species
M. pneumoniae – M. pneumoniae – ferments ferments glucoseglucose
M. hominisM. hominis – Hydrolyses – Hydrolyses ArginineArginine
U. urealyticumU. urealyticum – Hydrolyses – Hydrolyses UreaUrea
M. genitaliumM. genitalium - difficult to culture - difficult to culture

20. Genital MycoplasmosisGenital Mycoplasmosis
--TreatmentTreatment
Tetracycline orTetracycline or
 ErythromycinErythromycin