Clinical Classification and Incidence of Fulminant and Abortive Malignant Hyperthermia Reactions in Italy

A study made throughout Italy during the period 1990–1993 by the Malignant Hyperthermia (MH) Laboratory and the Italian MH Registry showed that the incidence of MH reactions in Italy was 1 in 51000. These data are not greatly different from the results reported by anesthesiologists in a retrospective investigation in four regions: Piemonte, Emilia Romagna, Veneto, and Tuscany, where the incidence was found to be about 1 in 70 000–75 000 and only the “very suspected MH reactions (fulminant and abortive)” were considered. The referred signs of MH adverse reactions—fulminant and abortive—were, first of all, tachycardia, arrhythmia, fever, rigidity, high values of creatine kinase (CK), myoglobinuria, acidosis, hypoxia, dark venous bleeding, and, when monitored, high end-tidal (ET) CO2. Following these clinical signs and considering their association with 110 MH reactions, 28 of the probands referred to the MH Italian Registry and to the four MH laboratories in the past 4 years (1990–1993) were classified as fulminant forms and 69 as abortive forms, with an incidence of 1 in 200 000 and 1 in 81000, respectively.