Severe COVID-19 in Hospitalized Carriers of Single CFTR Pathogenic Variants

Baldassarri, Margherita; Fava, Francesca; Fallerini, Chiara; Daga, Sergio; Benetti, Elisa; Zguro, Kristina; Amitrano, Sara; Valentino, Floriana; Doddato, Gabriella; Giliberti, Annarita; Di Sarno, Laura; Palmieri, Maria; Carriero, Miriam Lucia; Alaverdian, Diana; Beligni, Giada; Iuso, Nicola; Castelli, Francesco; Quiros-Roldan, Eugenia; Mondelli, Mario Umberto; Miceli, Rosalba; Frullanti, Elisa; Furini, Simone; Mari, Francesca; Renieri, Alessandra; Gabbi, Chiara

The clinical presentation of COVID-19 is extremely heterogeneous, ranging from asymptomatic to severely ill patients. Thus, host genetic factors may be involved in determining disease presentation and progression. Given that carriers of single cystic fibrosis (CF)-causing variants of the CFTR gene—CF-carriers—are more susceptible to respiratory tract infections, our aim was to determine their likelihood of undergoing severe COVID-19. We implemented a cohort study of 874 individuals diagnosed with COVID-19, during the first pandemic wave in Italy. Whole exome sequencing was performed and validated CF-causing variants were identified. Forty subjects (16 females and 24 males) were found to be CF-carriers. Among mechanically ventilated patients, CF-carriers were more represented (8.7%) and they were significantly (p < 0.05) younger (mean age 51 years) compared to noncarriers (mean age 61.42 years). Furthermore, in the whole cohort, the age of male CF-carriers was lower, compared to noncarriers (p < 0.05). CF-carriers had a relative risk of presenting an abnormal inflammatory response (CRP ≥ 20 mg/dL) of 1.69 (p < 0.05) and their hazard ratio of death at day 14 was 3.10 (p < 0.05) in a multivariate regression model, adjusted for age, sex and comorbidities. In conclusion, CF-carriers are more susceptible to the severe form of COVID-19, showing also higher risk of 14-day death.