Adverse effect of Pneumocystis Jirovecii infection associated with rituximab therapy for autoimmune disease are more frequently reported in older vs. younger patient.

INTRODUCTION: Rituximab is a chimeric anti-CD20 antibody commonly used to treat patients with autoimmune diseases. Such diseases mainly affect young people, but older patients may also be concerned. So far, very little data exist concerning the safety of rituximab in older patients with autoimmune diseases. METHODS: This study was intended to describe the adverse reaction profile of rituximab in patients over 75 years of age treated for autoimmune diseases and to compare such profile to those observed in patients below 75 years of age. Adverse reactions related to rituximab were reported to the French Pharmacovigilance Network. From such reports, a descriptive analysis as well as a disproportionality analysis were performed to identify safety signals. RESULTS: 1096 reports of rituximab-related adverse reactions reported in France between 2006 and 2019, were included in the study, such as 127 in the older group (>75 years) and 969 in the younger group (<75 years). Infusion reactions were less frequently reported than other adverse drug reaction in older patients (11 vs. 27%, P<0.001). By contrast, a higher rate of opportunistic infection due to Pneumocystis jirovecii was reported in the older subject group (3.9 vs. 0.6%, P<0.001), along with neutropenia (22.8 vs. 9.3%, P<0.0001). These results were confirmed by the disproportionality analysis. CONCLUSION: Pneumocystis jirovecii infection was significatively more reported in older patients treated by Rituximab which probably reflects a higher incidence in this population. The use of anti-pneumocystis prophylaxis should be considered in this population.

Cross-sectional reassessment after 4 years of clinical routine use of AQUIOS CL for absolute T cell quantitation in a university hospital.

BACKGROUND: We had previously reported appropriate performances of automated AQUIOS CL cytometer (Beckman Coulter) for regulatory approval of absolute T cell enumeration. However, after 4 years of routine use, we still observed recurrent histogram anomalies that may affect both absolute values and T cell subset percentages results. The objective of the current study was thus to perform a cross-sectional evaluation of these graphical anomalies within a university hospital context, to assess their influence on results and ultimately to propose a standardized decision tree to circumvent graphical disturbances at the time of results validation. METHODS: Eight hundred and sixty-two blood samples were prospectively analyzed on AQUIOS CL. Results were compared to (i) lymphocyte values from complete blood count; (ii) results from manual staining and analysis on Navios cytometer (Beckman Coulter); (iii) results after washing step and reacquisition on AQUIOS CL. RESULTS: Nearly 75% analyses did not show any graphical anomaly. 20% had single anomaly on "Lymphs (45)" or "Lymphs EV" regions influencing T cells percentages and requiring manual re-gating of "CD3- capture" region. 5% showed concomitant "Lymphs EV" and "Lymphs (45)" anomalies influencing both T cell percentages and absolute counting and requiring additional staining and analysis on Navios. Finally, <1% presented with anomaly on "CD4/CD8" histogram or "CD3+ All" region, influencing both T cell percentages and absolute counting. CONCLUSIONS: Around 25% AQUIOS CL results were flawed due to gating anomalies. In <5% cases, additional back-up procedures should be undertaken to ensure results validity. A simple decision-tree may help in guiding validation process.

Dual Ureaplasma parvum arthritis: a case report of U. parvum septic arthritis following contralateral reactive arthritis in an immunosuppressed patient.

BACKGROUND: Ureaplasma parvum is usually part of the normal genital flora. Rarely can it cause invasive infections such as genitourinary infections, septic arthritis, or meningitis. CASE PRESENTATION: Here we present the first description of chronic ureterocystitis in a 56-year-old immunocompromised patient, complicated first by reactive arthritis and secondarily by contralateral septic arthritis due to U. parvum infection. U. parvum was detected in synovial fluid and in a urine sample. Treatment consisted of double-J stenting and targeted antibiotic therapy. Evolution showed resolution of urinary symptoms and clinical improvement of arthritis despite functional sequelae. CONCLUSIONS: Given the high prevalence of U. parvum colonisation, this diagnosis should remain a diagnosis of exclusion. However, because of the difficulty in detecting this microorganism, it should be considered in unexplained subacute urethritis or arthritis, including reactive arthritis, especially in immunosuppressed patients. Real-time PCR positivity in the absence of a differential diagnosis should not be overlooked.