Improved microscopical diagnosis of pulmonary tuberculosis in developing countries

Research output: Contribution to journalArticle


The diagnosis of pulmonary tuberculosis (TB) relies on the bacteriological examination of sputum. However, microscopy of smears made directly from sputum has a low sensitivity and there is an urgent need for improved methods. We have compared microscopy of smears made directly from sputum with microscopy after liquefaction of sputum with household bleach (NaOCl) and concentration of bacteria by centrifugation. In 3 studies performed in Ethiopia and India, the use of the NaOCl method increased the number of samples positive for acid-fast bacilli by more than 100%. The technique is appropriate for developing countries and its application would increase the efficiency of TB control programmes. As a potent disinfectant, NaOCl also has the advantage of lowering the risk of laboratory infection.


  • Negussie Gebre
  • Ulf Karlsson
  • Göran Jönsson
  • Ragini Macaden
  • Alemnesh Wolde
  • Abraham Assefa
  • Håkan Miörner
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Microbiology in the medical area


  • tuberculosis, diagnosis by microscopy
Original languageEnglish
Pages (from-to)191-193
JournalTransactions of the Royal Society of Tropical Medicine and Hygiene
Issue number2
Publication statusPublished - 1995
Publication categoryResearch