**5. Specific bacterial immunotherapy (S.B.I.T)**

The immunological experience is treating osteomyelitis chronic forms at the Istituto Putti in Cortina starts in 1963 [11–13] by introducing immunotherapy, applied by the progressive administration in growing doses of a staphylococci pool, that had been collected from some patients with bone infections by the same germ and then inactivated in an aqueous solution suspension. At that time also autologous immunostimulation was carried out, i.e. a therapy prepared by isolating the responsible bacterial agent directly in the patient's exudate.

Also experiences with a *Pseudomonas aeruginosa* autologous immunotherapy have been carried out, but we abandoned it, as we saw that this bacterium wasn't the principal pathogenic agent, which provoked bone infections.

Nowadays only the isolation of Staphylococcus strains 5 and 8 is carried out, as only these strains are responsible for 98% of the bone infections. This aspect has been showed by a joint research with Institut Pasteur in Paris. We are working now only with these kinds of staphylococci and were able to better the general characteristics.

As already mentioned, administration is performed at growing dosages according to patterns adopted since long avoiding that too approached stimulation may exhaust the capacity responses as a consequence of a too prolonged stress.

The preparation is inoculated subcutaneously, and the therapy lasts about three months. After at least one month stop treatment may be repeated (**Figure 5**).

With reference to the above said we tried, together with "Immuno" in Vienna, to find out whether among chronic osteomyelitis patients there was some immunological deficit. We did not consider this evaluation had to be made on acute forms, as they show different characteristics while the host reactivity is still within the norm.

We evaluated therefore about 150 cases, with different ages and causes (hematogenic, post-traumatical and iatrogenous) and referred to following parameters:

#### **Figure 5.**

*Increasing subcutaneous injections of doses, according to a widely scheme (since 1963) of an inactivated staphylococci pool of type 5 and 8.*


This study ascertained indeed a reduction of the phagocytic activity as a whole, and especially the opsonisation activity.


It has been thought therefore that in immunotherapy more factors are involved; their principal property is to reduce the allergising effect and therefore to desensitise vs. the germ proteins and to increase the phagocytic activity.

This condition, neither whose entity nor its lasting may be defined, does not appear to be unlimited.

Obviously, this desensitisation can be obtained also by the right antibiotic choice that, as already said mainly in acute forms, may develop their bactericidal properties and sterilise the focus.

In the chronic forms it is possible to provoke this mechanism by carrying out a surgical toilette that restores the vascularization and stimulation conditions needed for a correct antibiotic action.

Checks upon immuno-stimulation treatment termination clearly showed corresponding results between laboratory deficit clinical conditions bettering laboratory bettering.
