Background Increased rate of severe infection (SI) in patients who exposed to immunosuppressive drugs has been a well-known complication in inflammatory rheumatic diseases. However,there are few reports on SI complicating AAV course.
Methods We investigated the characteristics of “SI requiring hospitalization” in AAV patients with lung involvement who were previously included into a study evaluating lung damage. Data were collected from hospital records between 2000-2014. Demographics, data on infection investigation including blood, sputum and urine cultures, viral serology, PPD/QTB tests, procalcitonin (PCT), imaging and biopsy findings, comorbidites, vasculitis activity and damage scores, cumulative dose of glucocorticoid (GC), cyclophosphamide (CYC) and rituximab (RTX) were noted into a predefined protocol. Infections that could not be revealed by cultures but succesfully treated with antibiotics were categorized as unidentified (UI). We compared the demographic and clinical data, comorbidities, initial BVAS and cumulative VDI scores and GC/CYC doses according to the presence of SI by Mann-Whitney U test.
Results Fifty-one AAV patients with lung involvement (25 female) (40 GPA, 8 MPA, 3 e-GPA) who were diagnosed according to ACR and CHCC criteria were included into the study. Age at diagnosis and duration of follow-up were as follows: 49±13 years (med 51), 67±52 mo (med 47). Lung (100%), kidney (78%), ENT (72%), nervous system (25%) were the involved organs. ANCA positivity was 94% (66% cANCA/anti-PR3, 34% p-ANCA/anti-MPO). Initial BVAS and cumulative VDI scores were 22±7 (4-38) (med 23), 3,4±2,2 (0-9) (med 3), respectively. Twenty-nine relapses occurred in 15 (29%) patients. Cumulative dose of GC and CYC were 16±9 g (med 14), 17±25 (med 6), respectively. RTX was used in 17 patients. Diabetes (18%), chronic kidney failure (25%) were the major comorbidities and 7% had ESRD. Influenza and pneumococcal vaccination and TMP-SMX prophylaxis were applied in one forth and two-thirds of AAV cohort, respectively. Eighty-seven SI noted in 25(52%) patients. Identified and unidentified SI in AAV cohort were shown in Table 1. Recurrent SI occurred in 27% of pulmonary and 33% of non-pulmonary groups. SI was associated with relapse in 16%. Serum PCT level increased in 93% (3.5±16.5, med 0.26) of 33 AAV patients. SI proportion was found to be increased during the first six months (%35) and after the 60th month of follow-up (30%). There were no significant difference between the patients with or without SI according to the risk factors. Four patients died from SI during follow-up.
Conclusions Prevalence of SI was high and had a bimodal pattern in the early and late phase of AAV. SI was found to have a high proportion of re-occurrence. SI complicated disease relapses in a small group of patients.
Disclosure of Interest None declared