*3.1. Clinical Patient Characteristics*

Between February 2020 and March 2021, a positive SARS-CoV-2 infection was demonstrated by PCR in eighteen LTRs. The median age was 49.9 years, and most patients were male (n = 12, 67%). The demographic and clinical characteristics are summarized in Table 1. The mean time since transplantation was 5.5 years, with cystic fibrosis and COPD being the most common pretransplant underlying disease (n = 6, 33% and n = 5, 28%, respectively).


**Table 1.** Patient characteristics according to COVID-19 disease severity.

BMI = body mass index.

The most common symptoms were fever (n = 9, 50%), nausea/vomiting (n = 7, 39%), cough (n = 6, 33%), dyspnea (n = 6, 33%) and fatigue (n = 6, 33%). Headache was reported by five patients (28%), and anorexia by three patients (23%). Only one patient (6%) reported altered sense of smell and taste (Table 2). Among the comorbidities, 10 patients (56%) had hypertension, six (33%) diabetes mellitus, six (33%) cardiovascular disease, eight (44%) chronic kidney disease and five (28%) a history of malignancy. Among the immunosuppressive drugs, 18 patients (100%) were long-term treated with prednisone, 15 patients (83%) had mycophenolate mofetil (MMF), 10 patients (56%) were on tacrolimus treatment, six patients (33%) had cyclosporine A, one patient (6%) had everolimus and one (6%) had rapamycin. Severity stages were classified according to Siddiqi, ranging from stage I to III. Seven (39%) patients had mild disease (stage I), five (28%) had moderate disease without hypoxemia (stage IIA), four (22%) with hypoxemia (stage IIB), while two (11%) were categorized as severe (stage III).
