Isolation of Leptospira biflexa from commercially prepared deionized water labeled "sterile for tissue culture".

Leptospira biflexa were isolated from urine cultures of two patients with clinical and laboratory findings compatible with leptospirosis. Neither patient had detectable leptospiral agglutinins. The source of the L. biflexa was water labeled " "sterile for tissue culture" purchased from M. A. Bioproducts, formerly Microbological Associates. M. A. Bioproducts water is sterilized by filtration through a 0.22-mum-pore size membrane filter. Leptospiral contamination can occur in products sterilized by filtration. Heat sterilization of water eliminates this possibility.