Effective definition of low humoral response to Clostridioides difficile infection.

BACKGROUND: Determination of the humoral response to Clostridioides difficile (CD) toxins could be of great value in the management of patients with CD infection (CDI). METHODS: A prospective study was conducted on the clinical characteristics and humoral response in patients with CDI. Determination of ELISA IgG CD anti-toxin B (tgcBiomics, Germany) was performed. The following dilutions were planned for each patient, 1:100, 1: 200, 1: 400, 1: 800: 1: 1600. A significant concentration of antibody was considered to be present in each dilution if an optical density 0.2 units higher than the negative control of the technique was evident. RESULTS: Eighty-five patients were included during the study period, November 2018-February 2020. The median age was 73 years (interquartile range: 62.5-85 years), with female predominance (45 patients, 52.9%). Thirty-nine patients (45.9%) had a severe infection. Seven patients (8.2%) had suffered an episode of CDI in the previous three months. Seventeen patients (20%) had one or more recurrent episodes during the three-month follow-up: No patient died during admission or required surgery for severe-complicated infection. The incidence of recurrence in patients with no antibody detected at 1:400 dilution was 25.4% (16 patients) while it was 4.3% (one patient) in patients with antibody present at that dilution (p = 0.03). Liver cirrhosis was associated with higher humoral response against CD. CONCLUSIONS: Antibodies IgG CD anti-toxin B detection at a dilution of 1:400, using a B ELISA technique, effectively identified patients at increased risk of recurrence. This information could help assist in the management of patients.

Prevalence of Cardiac Amyloidosis in Patients with Carpal Tunnel Syndrome.

Carpal tunnel syndrome (CTS) is a common finding among patients with cardiac amyloidosis. We sought to determine the prevalence of cardiac amyloidosis in patients who had undergone CTS surgery. From 2005 to 2014, 308 patients ≥ 60 years underwent CTS surgery. Of these, 233 (76%) agreed to participate in the study and 101 (73 ± 8 years; 68% females) showed left ventricular hypertrophy (LVH) ≥ 12 mm and underwent additional studies to diagnose AL and ATTR amyloidosis. Based on complementary studies, three patients were diagnosed with cardiac amyloidosis (two wild-type ATTR and one AL). The three patients showed bilateral CTS with no occupational risk factors. Prevalence of cardiac amyloidosis in the overall cohort was only 1.2% (3/233), but among patients with LVH and bilateral CTS, the prevalence was 5.5% (3/55) and 13.6% (3/22) if cases with an occupational risk factor were excluded. Cardiac amyloidosis should be excluded in the presence of bilateral CTS and particularly if an occupational risk factor is absent.

Anti-idiotypic vaccination in the treatment of low-grade B-cell lymphoma.

BACKGROUND AND OBJECTIVES: Patients with B-cell lymphoma can be induced to mount a specific immune response against the individual idiotypic determinants expressed in their tumor cells. This form of active immunotherapy is now under evaluation in the clinical setting. We evaluated the feasibility and effectiveness of this kind of immunotherapy in a group of patients with low-grade lymphoma, which included two cases of bi/triclonal lymphoma. DESIGN AND METHODS: Nine patients with a histopathologic diagnosis of follicular non-Hodgkin's (NHL) low-grade B-cell lymphoma were initially selected for this disease-free survival study. Idiotypic proteins were recovered by somatic fusion of the tumor cells and their identity with the tumor idiotype determined by molecular methods. The patients received the vaccine consisting of their tumor Ig protein coupled to keyhole limpet hemocyanine and were observed for toxicity, anti-idiotypic immune response, clinical outcome and circulating t(14;18)+ tumor cells. RESULTS: The median duration of follow-up was 40 (10-64) months from the initiation of immunotherapy. Tumor regression was detected in two patients. No tumor progression was observed in the other patients. Eight patients generated specific anti-idiotypic antibodies and 3 out of five were cleared of circulating t(14;18)+ cells. INTERPRETATION AND CONCLUSIONS: Induction of tumor-specific anti-idiotypic immune responses may be of benefit to patients affected by low-grade B-cell NHL. Our results are in line with those previously reported and call attention to the issue of tumor clonality in this kind of treatment.