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Istituto Superiore di Sanità
EpiCentro - Epidemiology for public health
Epidemiology for public health - ISS

Italian Haemolytic Uraemic Syndrome Registry

The Italian Haemolytic Uraemic Syndrome (HUS) Registry collects information on cases of this condition reported across the country. Data are recorded systematically and continuously. The registry is operated by the Italian Society of Paediatric Nephrology (Società Italiana di Nefrologia Pediatrica - SiNePe), in collaboration with the Istituto Superiore di Sanità (ISS). Cases of the disease are mainly reported by the paediatric and adult nephrology centres participating in the surveillance, through the HUS Registry information system (ISSEU).

Report / 1 December 2020 – 30 November 2021

HUS is considered a rare condition. In Italy, 54 cases were recorded between 1 December 2020 and 30 November 2021. Patients were from 14 different Regions. Of the 54 cases, 53 (98%) were recorded, as expected, in the paediatric population (<15 years of age). Over the last 12 months, the average notification rate for this age group has been 0.64 cases per 100,000 residents, with marked regional variations. The highest rate was observed in Apulia (1.8 cases per 100,000 residents). In this and six other Regions or Autonomous Provinces (Liguria, Emilia-Romagna, Piedmont, Lombardy, Friuli-Venezia Giulia and Autonomous Province of Bolzano), the notification rate was higher than the national average.

The number of HUS cases reported to the Italian Registry in the three months between September and November 2021 was 26.3% lower than expected, dropping to 12 from an average of 16.3 cases for the same period in the previous 10 years. Figures for the six months between December 2020 and May 2021 were also lower than the expected total for that time of year. By contrast, the number of HUS cases reported in June-August 2021 was slightly higher than expected: in August 2021, in particular, it was 18% higher than the average for that month in the previous 10 years.

HUS is known to predominantly affect the paediatric population (<15 years of age), and is often developed in the earliest years of life. The median age of clinical onset among the cases reported between 1 December 2020 and 30 November 2021 and in the previous 10 years was 22 months and 32 months, respectively. Only 1 HUS case was reported in the adult population between 1 December 2020 and 30 November 2021 (2% of the total).

Distribution by sex showed no significant differences between males and females.

Over the last 12 months, Shiga toxin-producing E. coli (STEC) infection has been confirmed by at least one laboratory test in 47 (89%) of the 53 HUS cases who had their stool and/or serum samples taken. Tests were carried out at the ISS National Reference Laboratory for E. coli or other laboratories approved by the Italian HUS Registry [1]. For 35 of the 47 positive cases, the STEC serogroup was also identified: in 80% (N=28) of the HUS cases for which this information was available, one of the top-5 STEC serogroups (O26, O157, O111, O145, O103) was detected. It should be noted that, in the last 12 months, STEC serogroup O80 has been detected in only one HUS case, despite accounting for an increasing number of cases in recent years. This is an important finding because, while the number of affected cases remains low, STEC O80 is still considered highly pathogenic and an emerging serogroup in Europe. In the remaining 12 cases, STEC infection was diagnosed using techniques that did not allow serogroup identification.


Risorse utili


Note 1: HUS (Molecular Epidemiology and Public Health Laboratory, University of Bari; Microbiology Laboratory of the Ca’ Granda Ospedale Maggiore General Hospital, Milan)


Last update: 13 January 2022

Publication date: 25 March 2021

Authors: Gaia Scavia, Eleonora Ventola, Arnold Knijn, Fabio Minelli, Paola Chiani, Stefano Morabito – Istituto Superiore di Sanità, Italian Haemolytic Uraemic Syndrome (HUS) Registry; Laura Massella, Italian Society of Paediatric Nephrology (SiNePe)