[Preliminary considerations in a semiquantitative microbiological study in catheter-related infection]

In the interval September 1993-April 1994, 38 catheters from children admitted to the Children's Hospital of Iaşi were examined microscopically and by semiquantitative culture, in the children with sepsis and/or positive catheters hemocultures being performed concurrently. Twenty eight of these catheters proved to be sterile, the other 10 being positive to coagulase-negative staphylococci, gram-negative bacilli from Klebsiella-Enterobacter group, Candida species, the number of colonies/plate varying generally in concordance with the microscopic positive score. Of the 6 cases with > 50 colonies/plate, 3 progressed to septicemia, their hemocultures being positive to the same bacterial species demonstrating an identical sensitivity spectrum to antibiotics (2 cases with Enterobacter cloacae, 1 case with Klebsiella oxytoca). These results correlated with a bacterioscopic score > +1, in a case, which concomitantly presented local phenomena of phlebitis, a PNC score +3 being recorded. To conclude with, the results of microscopic examinations and semiquantitative culture can differentiate the contaminated catheters from those at bacteremic risk. For defining the cutoff level of the significant number of colonies/plate, more positive samples are needed.