Pseudo-leptospires in blood culture

Spiral filaments seen in the blood cultures of two patients with fever and jaundice were initially thought to be leptospires; these were later proved to be artefacts. An investigation was carried out to exclude the possibility of laboratory contamination of the culture media and to find out how these objects were produced. The significance of the findings is discussed in relation to the possibility of a mistaken diagnosis in routine laboratories which have a limited experience of leptospires.