Ocrelizumab is an effective anti-CD20 therapy approved for Relapsing Remitting (RRMS) and Primary Progressive Multiple Sclerosis (PPMS). In clinical trials, a proportion of patients developed hypogammaglobulinemia which could contribute to infection risk. This study aimed to identify hypogammaglobulinemia and its risk factors and evaluate potentially associated serious infection risk in a real-world cohort of patients.

All MS patients treated with ocrelizumab in a Quebec City MS clinic from January 2017 to August 2021 were included and detailed patient characteristics were collected by chart review. Levels of immunoglobulins (IgM, IgA and IgG) were assessed prior to each treatment. Serious infection was defined as an infection requiring hospitalization or emergency room treatment. Association between hypogammaglobulinemia and serious infection was analyzed.

A total of 266 patients (average follow-up 2.05 years) were included (87% RRMS). After 6 infusions, 32.8%, 3.5% and 4.2% of patients had at least one IgM, IgA and IgG hypogammaglobulinemia event respectively. Aside from pre-treatment hypogammaglobulinemia, there were no variables associated with on-treatment hypogammaglobulinemia. There was a total of 21 serious infections (3.36 and 12.33 per 100-person-years in RRMS and PPMS). Developing hypogammaglobulinemia during treatment was not associated with serious infection. A regression analysis did not show associations between serious infection and key disease characteristics.

Similar to ocrelizumab extension studies, our cohort demonstrated a significant rate of hypogammaglobulinemia over time, mostly with IgM. No association was found between hypogammaglobulinemia and serious infection.

Since the beginning of the new millennium, prevalence of syphilis has re-increased and is once again, a major public health problem. Neurosyphilis is the extension of syphilitic infection to the nervous system. It is considered by many as a cause of reversible dementia, when treated early. However, scarce data exist on the evolution of cognitive and behavioral impairments in patients affected by tertiary neurosyphilis.

The aim of this study was to explore the cognitive and behavioral changes in a cohort of patients diagnosed with neurosyphilis.

A retrospective study based on systematized chart review between 2000 and 2012 in a large neurological tertiary care facility.

Clinical evaluations by treating physicians.

Eighteen patients were identified with tertiary neurosyphilis. Out of this group, only two had systematic neuropsychological follow-up despite physician reports of significant and persistent cognitive and psychiatric changes. For these two cases, only slight improvements were noted in memory and executive skills while improvements in attention were marked. None of our patients had previous psychiatric history yet a large proportion developed symptoms after the infection.

Although neurosyphilis is traditionally considered a reversible form of dementia, we found limited support for this claim in our two patients with close follow-up. Quality data on the cognitive and psychiatric changes in the rest of our cohort was dramatically lacking, and this could not be explained by absence of symptoms at presentation. Given the recrudescence of syphilis, we propose a systematic approach to the evaluation and follow-up of this disorder.