A girl, diagnosed enzymatically for MPS I (McKusick's OMIM (MPS I, Hurler syndrome, Scheie syndrome): 25280) at the age of 3 years and 9 months, was investigated until the age of 5 years and 4 months. Genetic analysis (performed by us) indicated that one allele of the alpha-L-iduronidase gene contains a mutation causing a common Q70X truncation in the enzyme amino acid sequence. Further studies (performed at Consorzio Genetica Moleculare Umana, Monza, Italy, supervised by Prof. Andrea Biondi and coordinated by Genzyme Co.) confirmed the presence of this allele and indicated that the second mutation is an in frame deletion of three base pairs (codon 349), resulting in the loss of aspartic acid residue (Delta349). The investigated MPS I patient suffered, between other symptoms characteristic for this disease, from frequent diarrhea or loose stools, often accompanied by vomiting. No obvious contacts with persons suffering from intestinal infections, including family members (who also had no documented chronic or often diarrhea), were noticed shortly before or during these episodes. During the most severe episodes of diarrhea, detailed microbiological analyses of stools were performed. The patient was never treated with antibiotics before stool collection, thus, results of microbiological assays were not affected by such a treatment. Bacterial, viral or fungal infections were detected in all these analyses (Table 1).
Isolation and preliminary analyses for identification and characterization of bacteria, viruses and fungi were performed using S-F selenium, blood agar, CNA, McConkey, SS, XLD, Sabouraud, Kligler and Singer, and BHI media (purchased from Becton Dickinson, Biomed or Bimex). Detailed analyses were performed using biochemical assay kits ID GN 32 (BioMerieux), EN-COCCUStest (Lachema) and ATB ID 32 C (BioMerieux), and immunological tests (kits purchased from Immunomed and BioMarieux). The microbiological assays were performed according to the semi-quantitative method, described previously. Non-enteropathogenic strains of Escherichia coli, strains of Enterococcus faecalis and small amounts of other bacteria belonging to Enterobacteriaceae were considered as normal aerobic bacterial flora. Identification of enteropathogenic E. coli strains was performed using a specific latex-immunological assay (purchased from Biomex). In this assay, 10 randomly chosen E. coli colonies (classified on the basis of microbiological and biochemical tests described above) were streak onto nutrient agar plates, and following 18 h incubation at 35 C bacteria were tested immunologically using the Biomex kit. The O antigens (characteristic for enteropathogenic E. coli strains but not for other strains of this bacterium), were detectable in this assay, and corresponding strains, bearing particular antigens, were divided into following groups: group A (antigens O26, O55, O111, O127 and O142), group B (antigens O86, O119, O124, O125, O126 and O128) and group C (antigens O18, O25, O44 and O114).