Cerebrospinal fluid CXCL13 concentration for diagnosis and monitoring of neurosyphilis in people with HIV.

OBJECTIVES: The study aimed to assess and compare cerebrospinal fluid (CSF)-CXCL13 levels in People with HIV (PWH) with suspected neurosyphilis (NS), those with syphilis but without NS, and patients without treponema infection. Additionally, it aimed to evaluate changes in CSF-CXCL13 concentrations before and after antibiotic treatment. DESIGN: This was a prospective cohort study involving 93 PWH suspected of NS. All participants underwent lumbar puncture, with CSF-CXCL13 levels measured at baseline and during follow-up in patients diagnosed with NS. METHODS: CSF-CXCL13 levels were quantified using ELISA. The Mann-Whitney U test was used to analyze differences between groups, while the Wilcoxon test assessed within subject changes. ROC curve analysis determined the diagnostic efficacy of CSF-CXCL13 for NS. RESULTS: Significantly higher CSF-CXCL13 levels were observed in patients with NS compared to those with syphilis without NS and non-syphilis patients. Posttreatment, a decline in CSF-CXCL13 levels was noted in all NS cases. A CSF-CXCL13 threshold exceeding 60.0 pg/ml, in conjunction with reactive CSF-FTA-ABS, yielded a sensitivity of 88.9% and a specificity of 97.6% for NS diagnosis. CONCLUSIONS: CSF-CXCL13 emerges as a valuable adjunctive biomarker for detecting NS in PWH, especially in cases with nonreactive CSF-VDRL. Monitoring CSF-CXCL13 levels also appears effective in evaluating therapeutic response in PWH undergoing NS treatment.

Antibody indexes in COVID-19 convalescent plasma donors: Unanswered questions.

OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is characterized by high contagiousness, as well as variable clinical manifestations and immune responses. The antibody response to SARS-CoV-2 is directly related to viral clearance and the antibodies' ability to neutralize the virus and confer long-term immunity. Nevertheless, the response can also be associated with disease severity and evolution. This study correlated the clinical characteristics of convalescent COVID-19 patients with immunoglobulin A (IgA) and IgG anti-SARS-CoV-2 antibodies. METHODS: This study included 51 COVID-19 health care professionals who were candidates for convalescent plasma donation from April to June 2020. The subjects had symptomatic COVID-19 with a polymerase chain reaction-confirmed diagnosis. We measured anti-SARS-CoV-2 IgA and IgG antibodies after symptom recovery, and the subjects were classified as having mild, moderate, or severe symptoms. RESULTS: Anti-SARS-CoV-2 antibodies were positive in most patients (90.2%). The antibody indexes for IgA and IgG did not differ significantly between patients presenting with mild or moderate symptoms. However, they were significantly higher in patients with severe symptoms. CONCLUSIONS: Our study showed an association between higher antibody indexes and severe COVID-19 cases, and several hypotheses regarding the association of the antibody dynamics and severity of the disease in SARS-CoV-2 infection have been raised, although many questions remain unanswered.

Antibody indexes in COVID-19 convalescent plasma donors: Unanswered questions

OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is characterized by high contagiousness, as well as variable clinical manifestations and immune responses. The antibody response to SARS-CoV-2 is directly related to viral clearance and the antibodies' ability to neutralize the virus and confer long-term immunity. Nevertheless, the response can also be associated with disease severity and evolution. This study correlated the clinical characteristics of convalescent COVID-19 patients with immunoglobulin A (IgA) and IgG anti-SARS-CoV-2 antibodies. METHODS: This study included 51 COVID-19 health care professionals who were candidates for convalescent plasma donation from April to June 2020. The subjects had symptomatic COVID-19 with a polymerase chain reaction-confirmed diagnosis. We measured anti-SARS-CoV-2 IgA and IgG antibodies after symptom recovery, and the subjects were classified as having mild, moderate, or severe symptoms. RESULTS: Anti-SARS-CoV-2 antibodies were positive in most patients (90.2%). The antibody indexes for IgA and IgG did not differ significantly between patients presenting with mild or moderate symptoms. However, they were significantly higher in patients with severe symptoms. CONCLUSIONS: Our study showed an association between higher antibody indexes and severe COVID-19 cases, and several hypotheses regarding the association of the antibody dynamics and severity of the disease in SARS-CoV-2 infection have been raised, although many questions remain unanswered.