High Risk of Secondary Infections Following Thrombotic Complications in Patients With COVID-19
Authors: Ripa Marco , Galli Laura , D’Angelo Armando , Apruzzi Luca , Palumbo Diego , Campochiaro Corrado , Tassan Din Chiara , Danise Anna , Da Prat Valentina , Vitali Giordano , Brugliera Luigia , Poli Andrea , Monardo Roberta , Monti Giacomo , Baccellieri Domenico , De Cobelli Francesco , Clementi Massimo , Iannaccone Sandro , Dagna Lorenzo , Rovere-Querini Patrizia , Ciceri Fabio , Tresoldi Moreno , Zangrillo Alberto , Scarpellini Paolo , Castagna Antonella ,   COVID-BioB Study Group, Andolina Andrea , Bigoloni Alba , Bossolasco Simona , Bruzzesi Elena , Canetti Diana , Castiglioni Barbara , Cernuschi Massimo , Chiurlo Matteo , Cinque Paola , Dell’Acqua Raffaele , Della Torre Liviana , Gianotti Nicola , Guffanti Monica , Hasson Hamid , Messina Emanuela , Morsica Giulia , Nozza Silvia , Ranzenigo Martina , Uberti-Foppa Caterina , Vinci Concetta , Badalucco Ciotta Flavia , Bottanelli Martina , Clemente Tommaso , Mainardi Ilaria , Mori Giovanni , Papaioannu Borjesson Rebecka , Ponta Giacomo , Muccini Camilla , Mastrangelo Andrea , Oltolini Chiara , Spagnuolo Vincenzo , Benassi Luca , Bigai Giorgia , Bozzolo Enrica , Borio Giorgia , Bussolari Cecilia , Calvisi Stefania , Canti Valentina , Castellani Jacopo , Cavallo Ludovica , Cilla Marta , Cinel Elena , Compagnone Nicola , D’Aliberti Teresa , Damanti Sarah , De Lorenzo Rebecca , Di Lucca Giuseppe , Di Terlizzi Gaetano , Dumea Iulia , Farolfi Federica , Ferrante Marica , Frangi Claudia , Gallina Gabriele , Germinario Bruno Nicolò , Lanzillotta Marco , Li Voti Raffaele , Marinosci Alessandro , Martinenghi Sabina , Memoli Massimo , Montagna Marco , Pascali Maria , Patrizi Alessandro , Pomaranzi Chiara , Scotti Raffaella , Strada Silvia , Boffini Nicola , Cavalli Giulio , Della Torre Emanuel , De Luca Giacomo , Farina Nicola , Moroni Luca , Ramirez Giuseppe Alvise , Tomelleri Alessandro , Azzolini Maria Luisa , Baiardo Redaelli Martina , Calabrò Maria Grazia , Casiraghi Giuseppina Maria , Dell’Acqua Antonio , Fresilli Stefano , Guzzo Francesca , Landoni Giovanni , Lombardi Gaetano , Maimeri Nicolò , Moizo Elena , Nisi Francesco Giuseppe , Oriani Alessandro , Ortalda Alessandro , Pasculli Nicola , Pieri Marina , Turi Stefano , Bertoglio Luca , Bilman Victor , Carletti Silvia , Gona Floriana , Mancini Nicasio , Della Valle Patrizia , Molinari Chiara , Poloniato Antonella , Lalla Francesca , Prestifilippo Dario , Sapienza Jacopo , Seghi Federico 
Published: September 2022

Background

This study’s primary aim was to evaluate the impact of thrombotic complications on the development of secondary infections. The secondary aim was to compare the etiology of secondary infections in patients with and without thrombotic complications.

Methods

This was a cohort study (NCT04318366) of coronavirus disease 2019 (COVID-19) patients hospitalized at IRCCS San Raffaele Hospital between February 25 and June 30, 2020. Incidence rates (IRs) were calculated by univariable Poisson regression as the number of cases per 1000 person-days of follow-up (PDFU) with 95% confidence intervals. The cumulative incidence functions of secondary infections according to thrombotic complications were compared with Gray's method accounting for competing risk of death. A multivariable Fine-Gray model was applied to assess factors associated with risk of secondary infections.

Results

Overall, 109/904 patients had 176 secondary infections (IR, 10.0; 95% CI, 8.8–11.5; per 1000-PDFU). The IRs of secondary infections among patients with or without thrombotic complications were 15.0 (95% CI, 10.7–21.0) and 9.3 (95% CI, 7.9–11.0) per 1000-PDFU, respectively (P = .017). At multivariable analysis, thrombotic complications were associated with the development of secondary infections (subdistribution hazard ratio, 1.788; 95% CI, 1.018–3.140; P = .043). The etiology of secondary infections was similar in patients with and without thrombotic complications.

Conclusions

In patients with COVID-19, thrombotic complications were associated with a high risk of secondary infections.