“…The following countries were involved in the selected studies: Switzerland (2, 22.2%) [ 10 , 11 ], Italy (2, 22.2%)[ 11 , 12 ], Japan (1, 11.1%) [ 13 ], China (1, 11.1%) [ 14 ], Egypt (1, 11.1%) [ 15 ], UK (1, 11.1%) [ 16 ], Greece (1, 11.1%)[ 16 ], and Pakistan (1, 11.1%)[ 17 ]. Studies were mono-center in most of the cases (6, 66.7%) [ 10 , 12 – 15 , 17 ], whereas multi-center in only two (25%)[ 10 , 16 ] studies. Three (33.3%) [ 10 , 13 , 17 ] case-series recruiting ≥ 10 patients were selected; five (62.5%) [ 11 , 12 , 14 – 16 ] studies were observational and retrospective, without providing further epidemiological details.…”