POS1257 HYPOGAMMAGLOBULINEMIA IS A SIGNIFICANT RISK FACTOR FOR MORTALITY IN PATIENTS WITH ANCA ASSOCIATED VASCULITIS AND COVID-19
Authors: B. Ince, M. Bektas, N. Koca, B. F. Agargun, S. Zarali, D. Y. Guzey, Y. Yalçinkaya, B. Artim-Esen, A. Gül, M. Inanc
Journal: Annals of the Rheumatic Diseases (2021)

Background: The negative impact of COVID-19 in patients with ANCA associated vasculitis (AAV) and patients on rituximab (RTX) treatment have been reported (1). Risk factors for severe course of COVID-19 and increased mortality in these patients are unclear. Objectives: To evaluate the course of COVID-19 in our AAV cohort and identifying risk factors for mortality. Methods: Patients with AAV who were classified according to CHCC and whose scheduled last visit were after December 2019 were screened and evaluated for COVID-19 either by phone call or in the clinic. Records of patients with a history of hospital admission due to COVID-19 were evaluated. Cumulative clinical findings and treatment history were noted. Hypogammaglobulinemia (hIgG) was defined as IgG level below 700 mg/dl. All inpatients with a diagnosis of COVID-19 were screened for hIgG and IVIG was administered if necessary. Results: Eighty-nine patients (47.2% female, mean age 56 + 12.5 (28-81)) were included into the study. The diagnosis was GPA in 56 (62.9%) and MPA in 33 (37.1%) patients. Mean follow up time was 91 + 53.4 (26-272) months. Anti-PR3 and anti-MPO were positive in 46 (51.7%) and 32 (35.9%) patients, respectively. Lower respiratory tract (LRT) involvement was present in 72 (80.9%) and 10 patients had a history of diffuse alveolar haemorrhage (DAH). Sixty-one patients (68.2%) had a history of rapidly progressive glomerulonephritis (RPGN) and 21 (23.6%) had peripheral nervous system (PNS) involvement. Fifteen (16.9%) patients had COVID-19; 14 of them were PCR positive, one patient had symptoms and thorax CT findings compatible with COVID-19. Pulmonary infiltrates were observed in 13 patients (86.7%); 9 (60%) had severe pneumonia. Twelve patients (85.7%) were hospitalized, 6 patients (42.9%) needed ICU admission and 5 patients (35.7%) died. Tocilizumab and anakinra for hyperinflammation during COVID-19 were used in 1 (6.7%) and 4 (26.7%) patients, respectively. Four out of five deceased patients (3 on RTX treatment, 1 with renal transplant) were in remission at the time of COVID-19. COVID-19 was detected in a patient with disease flare and DAH, during treatment with high dose steroids and plasmapheresis. hIgG was detected in all deceased patients from COVID-19 during hospital admission (mean IgG: 495±113.2 mg/dL). Symptomatic COVID-19 was more frequent in patients with a history of DAH, RPGN and hIgG. hIgG during the follow-up was significantly associated with COVID-19 in multivariable analysis (p=0.01, OR=20,6 %95 CI (2-210). Comparison of patients who died of COVID-19 and survived showed that female sex, PNS involvement and hIgG during the clinical course and hospital admission were risk factors for increased mortality (Table 1). Age, smoking, treatments, history of flares or serious infections, remission status and chronic renal insufficiency did not differ between groups. Conclusion: The frequency and mortality from COVID-19 is found to be high in our AAV cohort compared to previous reports (1). Patients with serious lung or renal involvement are prone to symptomatic COVID-19. Previously reported severe outcomes on RTX therapy might be related to consequent hIgG. High dose IVIG treatment may not be sufficient in improving survival in AAV patients with severe COVID-19 and hIgG. References: [1]Severity of COVID-19 and survival in patients with rheumatic and inflammatory diseases: data from the French RMD COVID-19 cohort of 694 patients. 2020:annrheumdis-2020-218310. Table 1. Comparison of risk factors for CI and mortality in patients with AAV COVID-19 (n=15) Non-infected (n=74) p OR Death (n=5) Survive (n=10) p2 OR2 Age 53.4±11.9 56.6±12.6 NS 51.2±12.6 54.6±12.1 NS Sex (female) 6 35 NS 4 2 0.036 14 (0.9-207) LRT Involvement 14 58 NS 5 9 NS DAH 4 6 0.038 4.1 (1-16.9) 1 3 NS RPGN 15 46 0.004 8.5 (1-68.4) 5 7 NS PNS involvement 3 18 NS 3 0 0.005 9 (1.4 - 57) RTX treatment 10 33 NS 3 7 NS hIgG in outpatient visits 6 7 0.02 6.3 (1.8-23.3) 4 2 0.02 16(1.5-234) hIgG during hospitalization due to CI - - - - 5 4 0.025 2.5 (1.2-5.4) Flares≥1 7 25 NS 4 3 NS Chronic Renal Insufficiency 7 22 NS 4 3 NS Disclosure of Interests: None declared