The Ito-Reenstierna test is an intradermal test, using inactivated Haemophilus ducreyi, for diagnosis of chancroid. Due to limited sensitivities for detection of circulating antibodies to H. ducreyi, serology has currently limited usefulness in the routine diagnosis of chancroid infection but may be useful in population-based epidemiological research as a screening method for past infection. Ref: Lautenschlager S (2012). Chapter 202. Chancroid. In Goldsmith L.A., Katz S.I., Gilchrest B.A., Paller A.S., Leffell D.J., Wolff K (Eds), Fitzpatrick's Dermatology in General Medicine, 8e.