Current knowledge of rickettsial diseases in Italy.

Rickettsial diseases continue to be the cause of serious health problems in Italy. From 1998 to 2002, 4,604 clinical cases were reported, with 33 deaths in the period from 1998 to 2001. Almost all the cases reported in Italy are cases of Mediterranean spotted fever (MSF). Other rickettsioses that have been historically documented are murine typhus and epidemic typhus. Since 1950, only sporadic cases of murine typhus have been reported, and Italy currently appears to be free of epidemic typhus. As in other European countries, imported cases of rickettsialpox, African tick-bite fever (ATBF), and scrub typhus have been reported. In 2004, three cases of a mild form of rickettsiosis were serologically attributed to Rickettsia helvetica.

Characterization of the first Bartonella henselae strain isolated from a cat in Italy.

Bartonella henselae has been identified and characterized for the first time in Italy. A strain, designed Pavia-1, was isolated from the blood of a cat whose owner developed cat scratch disease (CSD). Pavia-1 and two American B. henselae strains (Houston-1, ATCC 49882, type I and strain 269608, UC Davis, type II) were compared by whole-cell fatty analysis (CFA), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for protein profiles, Western immunoblotting (WB) for reactivity with polyclonal antibodies, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), type-specific 16S rRNA PCRs, and pulsed-field gel electrophoresis (PFGE). Bartonella clarridgeiae (ATCC 51734) was also included for comparison. Pavia-1 was identified as a B. henselae type I. PFGE allowed differentiation between B. clarridgeiae and B. henselae and furthermore, between all the B. henselae strains. The fingerprints of PFGE observed for Pavia-1 were distinct from those of B. henselae type II and also of Houston-1, suggesting that the two type I strains derived from two different clones. These results show the capability of B. henselae to develop genotypic variability between genetically related strains.

Differentiation of leptospires of the serogroup Pomona by monoclonal antibodies, pulsed-field gel electrophoresis and arbitrarily primed polymerase chain reaction.

All reference strains described as representing separate serovars belonging to the serogroup Pomona and a clinical leptospiral isolate (LP2) from this serogroup were analyzed using a battery of 9 monoclonal antibodies, pulsed-field gel electrophoresis (PFGE) and arbitrarily primed polymerase chain reaction (AP-PCR). Monoclonal antibody analysis provided taxonomic results which were in agreement with the current classification of the serogroup Pomona into six serovars and allowed the classification of the isolate LP2 in the serovar pomona. PFGE and AP-PCR, although in general agreement with monoclonal antibody analysis, also were able to demonstrate some differences in the restriction patterns of strains Pomona, Monjakov and CB. These results indicate that these strains, grouped within serovar pomona after the introduction of bacterial restriction endonuclease analysis as the typing method, but formerly described as representing separate serovars (pomona, monjakov and cornelli, respectively), are similar but not identical to one another. This was also the case with strains 5621, the serovar mozdok reference strain, and K1, formerly described as serovar dania reference strain, but currently recognized to be a mozdok-like strain. These findings suggest that the deletion of some serovars within the serogroup Pomona, namely mozdok, cornelli, and dania, should be reconsidered. Thus, PFGE appears to be a useful tool for the serovar identification of leptospires belonging to the serogroup Pomona and for shedding light on the problem of their classification.