Patients with primary antibody deficiency are at risk for severe and in many cases for prolonged COVID-19. Convalescent plasma treatment of immunocompromised individuals could be an option especially in countries with limited access to monoclonal antibody therapies. While studies in immunocompetent COVID19 patients have demonstrated only a limited benefit, evidence for the safety, timing, and effectiveness of this treatment in antibody-deficient patients is lacking. Here, we describe 16 cases with primary antibody deficiency treated with convalescent plasma in four medical centers. In our cohort, treatment was associated with a reduction in viral load and improvement of clinical symptoms, even when applied over a week after onset of infection. There were no relevant side effects besides a short-term fever reaction in one patient. Longitudinal full-genome sequencing revealed the emergence of mutations in the viral genome, potentially conferring an antibody escape in one patient with persistent viral RNA shedding upon plasma treatment. However, he resolved the infection after a second course of plasma treatment. Thus, our data suggest a therapeutic benefit of convalescent plasma treatment in patients with primary antibody deficiency even months after infection. While it appears to be safe, PCR follow-up for SARS-CoV-2 is advisable and early re-treatment might be considered in patients with persistent viral shedding.

Background Vascularized bone grafts from the medial femoral condyle (MFC) are used to gain surgical revascularization of osseous defects. To date objective data regarding the donor site morbidity are limited. This study aims to evaluate the donor site associated outcome after MFC flap harvest. Patients and Methods From 2008 to 2016, 22 patients who underwent MFC bone flap harvest for osseous revascularization of 9 talus, 8 scaphoids, 2 metacarpals, 1 phalanx, 1 pilon tibiale, and 1 distal femur were included. Outcome analysis was performed for the whole cohort as well as for two subgroups (recipient site upper [group A] and lower extremity [group B]) by the lower extremity functional scale (LEFS), the OAK‐score of the Swiss Orthopedic Society and the visual analog scale (VAS). Additionally, a 3D gait analysis was performed for four patients. Results The mean flap size was 1 × 1 × 3 cm. No flap loss was observed. One minor surgical revision was performed due to donor site hematoma. Mean follow‐up was 35.8 (12–98) months. Mean LEFS‐score was 74.9 ± 9.5 (A: 74.3 ± 7.9; B: 75.6 ± 11.2, p > .05) and OAK‐score was 92.8 ± 9.4 (A: 93.2 ± 5.8; B: 92.4 ± 12.3, p > .05). At follow‐up examination, pain at rest was stated with 0.1 ± 0.2 (A: 0.1 ± 0.3; B 0 ± 0, p > .05) and with activity 0.6 ± 1.4 (A: 1.2 ± 1.8; B: 0 ± 0, p > .05) on VAS. The 3‐D gait analysis showed normative walking patterns. Conclusion After MFC flap harvest knee function and gait pattern were almost unimpaired. Donor site morbidity can be considered as being of minor concern in the decision‐making for this microvascular procedure.

No abstract