Treponema Pallidum

Penicillin G REF: Microbiology, Volume 2; Volume 9, Part 2 edited by E. Edward Bittar, Neville Bittar page 241

See APPENDIX-65 for “SEXUALLY TRANSMITTED DISEASES”

“Parenteral penicillin G remains the treatment of choice for syphilis (Treponema pallidum) and resistance to penicillin has not been reported”

According to Harrison

“Treponema pallidunt has been recovered from C.S.F. during primary and secondary syphilis in 30% of cases”.

Ans. is ‘b’ i.e., Treponema pallidum

Ans. is ‘a’ i.e., Treponema pallidum

Ans. is ‘b’ i.e., Motile by peritrichate flagella 

Morphology

–    Elongated, flexible

Twisted spirally along the long axis

–       Motile by endoflagella, which are polar flagella.

Grant negative

– Can not be seen under light microscope in wet films but can be made out by negative staining with India ink. – pallidum does not take ordinary stains, but stain light rose red with prolonged Giemsa staining. – Morphology and motility can be seen under the dark ground or phase contrast microscope.

–  It can be stained by silver impregnation methods.

– Fontana’s method is useful for staining films.

– Levaditis’s method for tissue sections.

Cultivation

Do not grow in artificial culture media.

Virulent strains can be maintained by serial testicular passage in rabbits eg. Nichol’s strain

–   It is possible to maintain T. pallidum in motile and virulent form for 10-12 days in complex media under anaerobic conditions.

– Reiter strain (T phagedenis) – Non pathogenic treponeme, can grow in artificial culture.

– In its time, TPI was the most specific test available for diagnosis of syphilis and was considered the gold standard in syphilis serology. However because of its complexity, it has now been suplanted by other tests such as FTA-ABS and TPHA, which are quite as specific and much simpler.

Ans. is ‘b’ i.e., Hyaluronidase – enhances invasiveness 

“T pallidum has hyaluronidase that breaks down the hyaluronic acid in the ground substance of tissue and presumably enhances, invasiveness of the organism.” 

About other options

.  Antibody to cardiolipin (diphosphatidyl glyceral – DPG) is nonspecific as cardiolipin antigen is present both in T. pallidum and in mammalian tissue.

Antigenic structures of T. pallidum

.  Antigenic structure of T. pallidum is complex. Treponemal infection induces at least three type of antibodies.

Ans. is ‘c’ i.e., Treponema pallidum

.  Treponema pallidum is an obligate intracellular organism. Thus it cannot be cultivated in cell free medium.

.   Pneumocystis Jiroveci and Rhinosporidium seeberi can not be cultivated.

Ans. is ‘c’ i.e., Treponema pallidum

.   Susceptibility of T. pallidum to heat was the basis of the fever therapy for syphilis.

.   It is killed in 1-3 days at 0-4°C, so that transfusion syphilis can be prevented by storing blood for at least four days in the refrigerator before transfusion.

Ans. is ‘d’ i.e., Treponema pallidum

Ans. is ‘c’ i.e., Schaudinn and Hoffman 

Ans. is ‘a’ i.e., Fontana’s 

• Can not be seen under light microscope in wet films but can be made out by negative staining with India ink.
• L pallidum does not take ordinary stains, but stain light rose red with prolonged Giemsa staining.
• Morphology and motility can be seen under the dark ground or phase contrast microscope.
• It can be stained by silver impregnation methods.
• Fontana’s method is useful for staining films.
• Levaditis’s method for tissue sections.