Response to: 'Severe COVID-19 associated pneumonia in 3 patients with systemic sclerosis treated with rituximab' by Avouac et al .

We read with deep interest the comments by Avouac and colleagues1 and their report of severe cases of COVID-19 in three patients with systemic sclerosis (SSc) under rituximab treatment. The heterogeneous profile of patients as well as the potential implication of comorbidities appear to be the hallmarks of this viral outbreak. Applied to the field of SSc, the absence of pre-existing interstitial pneumonia is an illustration of the viral ability to surprise and challenge our classic thinking. A singular profile of patients with both autoimmune disease and COVID-19 has not yet emerged, and each patient may be a special case when faced with COVID-19, considering the gathering and interplay of pathophysiological mechanisms and clinical features of the rheumatic disease, comorbidities,2 viral aggression and immune response against coronavirus.3 The weight of comorbidities is at least illustrated by the high number (until today: 323) of referenced papers on PubMed, while numerous risk factors are suspected and debated.2 To date, large data concerning rituximab during the pandemic are lacking, and whether rituximab is associated with a specific risk of more severe …