Concordance of interstitial cystitis in monozygotic and dizygotic twin pairs

Our objective was to determine whether there is a greater concordance of in terstitial cystitis (IC) among monozygotic than dizygotic twins. Members of the Interstitial Cystitis Association (ICA) who responded to a survey abou t first-degree family members with IC symptoms or confirmed IC were request ed to identify themselves if they were 1 of a twin pair. Each twin responde nt and co-twin were then evaluated via a questionnaire and acquisition of h ydrodistention reports as to their meeting modified National Institute of D iabetes and Digestive and Kidney Diseases (NIDDK) criteria for IC, Of the c o-twins of 8 monozygotic twin respondents, 2 had probable and 3 had confirm ed IC compared with none of the co-twins of the 26 dizygotic twin responden ts (including 15 female co-twins). There is a greater concordance of IC amo ng monozygotic than dizygotic twin pairs suggesting a genetic susceptibilit y to IC. (C) 2001, Elsevier Science Inc.