Follow-Up Study of Anti-SARS-CoV-2 IgG Antibody Response in COVID-19 Patients up to 6 Months After Infection

Abstract

Introduction: The aim of the current study was to investigate the relationship between lung involvement of SARS-CoV-2 and antibody levels of COVID-19 patients 3 and 6 months from the disease. Methods: A total of 156 participants were divided into two groups, Group 1: lung involvement (LI)-positive and Group 2: LI-negative. Biochemical parameters and anti-SARS-CoV-2 IgG antibody levels were measured. Results: The results showed that mean levels of urea, LDH, CRP, ferritin, neutrophil count and D-dimer were significantly higher in the LI-positive group. In addition, mean antibody levels in the 3rd and 6th months were higher in the LI-positive group (p < 0.005). Discussion: High antibody levels in LI-positive patients correlated with some immunologic and biochemical parameters. Further studies should be performed to determine protective antibody levels against reinfection, how long protective titers last and the mechanisms by which COVID-19 symptoms, demographics and comorbidities may drive higher antibody levels.

Lactate dehydrogenase contribution to symptom persistence in long COVID: A pooled analysis

“…Finally, 46 studies with 8289 participants (3338 PASC and 4951 controls) were included in our pooled analysis (Table 1). 24–69 These included studies were all peer‐reviewed, published between 2020 and 2023; had data from 28 studies in Resp‐PASC, 10 studies in Neuro‐PASC, 5 studies in Cardio‐PASC, 2 studies in gastrointestinal‐PASC and as only 1 study was in Reno‐PASC. Thirty‐four studies were of cohort design, 11 were case control and 1 cross‐sectional.…”

“…The duration of follow‐up varied among the studies from 2 to 12 months. Majority of the studies reported ICU admission of 4%–100% except a few studies that had mostly mildly COVID‐19 cases in their cohorts during acute infection 28,41,56,68 . Twenty‐four included studies were rated ‘good’ while 22 studies were rated to be of ‘moderate score’ based on the criteria outlined in NOS and Joanna Briggs Institute Critical Appraisal checklist [Supplementary Table and ].…”

“…Majority of the studies reported ICU admission of 4%-100% except a few studies that had mostly mildly COVID-19 cases in their cohorts during acute infection. 28,41,56,68 Twenty-four included studies were rated 'good' while 22 studies were rated to be of 'moderate score' based on the criteria outlined in NOS and Joanna Briggs Institute Critical Appraisal checklist [Supplementary Table 2A and 2B]. A total of 17% of included studies reported the LDH analytical tool employed in their study (Table 1).…”