A multi-centre retrospective study on intestinal parasitosis in Italy, 20052007

Abstract number: R2237

Raglio A., Arosio M., Crotti D., Gatti S., Bargiggia G., Bernieri F.

Objectives: Many data on the epidemiology of intestinal parasitosis are available for developing area, not so for industrialised countries. Our aim was to describe the epidemiology of parasitic intestinal infections in Italy, through a multicentre study coordinated by Association of Italian Clinical Microbiologists – Committee of Parasitology.

Methods: We asked twelve laboratories throughout the country to fill a questionnaire about their diagnostic methods and local epidemiology related to the period of 1 January 2005–31 December 2007. The attention was pointed to evaluate the results of standard stool parasitological examination (O&P), cellophane-tape test, Baermann/larvae culture methods and permanent stain (acid fast stain, Giemsa or trichrome stain) for intestinal helminths and protozoa.

Results: All the laboratories performed O&P and cellophane-tape test. 33524 samples were tested by O&P, 337 (1.0%) were positive for helminths and 851 (2.54%) for pathogen Protozoa. Helminths were: Taenia spp. 0.35%, Hymenolepis spp. 0.18%, A. lumbricoides 0.13%, T. trichiuria 0.12, Ancylostoma spp. 0.08%, S. mansoni 0.05%, D. latum 0.04% and 851/33524 (2.54%); Protozoa were: G. lamblia 2.15%, E. histolytica/dispar 0.36% and I. belli 0.02%. 2313 samples were examined by cellophane-tape test, 252 (10.89%) were positive for E. vermicularis. 7/12 labs used Baermann or larves culture methods for isolation of S. stercoralis: 196/14170 were positive (1.38%). 6/12 labs performed Giemsa and 2/12 labs trichrome stain for D. fragilis: 378/16357 (2.31%). All laboratories used acid fast stain for Cryptosporidium spp.: 44/2647 (1.66%). 4/12 labs used antigen detection for E. histolytica/dispar. Only 1 lab cultured suspected cases for E. histolytica by Robinson medium: 83/403 (20.6%).

Conclusions: Not all the labs are still organised for good faecal diagnostics and are available to performe adequate data collection. Anyway, faecal parasites and particularly helminths, excluding E. vermicularis and S. stercoralis, are very rare in Italy. Moreover, more labs should investigate for D. fragilis using at least Giemsa stain, and research specifically S. stercoralis when risk factors are present. For E. histolytica the antigen detection is useful but the gold standard remains the culture that is still available in few labs.