Post-discharge follow-up of pediatric COVID-19 patients: insights into serological dynamics.

Introduction: Limited data are available regarding SARS-CoV-2 serological response dynamics in pediatric patients with COVID-19, contributing to gaps in our understanding of the immune response in this population. This study aimed to investigate SARS-CoV-2 IgG seropositivity in patients diagnosed with COVID-19 during hospitalization and 2-4 weeks after discharge. Methods: A cohort of patients, consisting of 31 individuals with confirmed acute COVID-19 infection and 27 diagnosed with Multisystem Inflammatory Syndrome in Children (MIS-C), was enrolled in the study. Follow-up clinic appointments were scheduled for 2-4 weeks post-discharge. During admission and follow-up, blood samples were collected from each patient for laboratory analysis. Anti-nucleoprotein SARS-CoV-2 IgG levels were determined using the Enzyme-Linked Immunosorbent Assay (ELISA) method. Results: In this study, a cohort of 58 patients was examined. At admission, 52% (n = 14) of MIS-C patients and 10% (n = 3) of acute COVID-19 patients had positive SARS-CoV-2 IgG test. Only 48 cases were referred to the hospital, and follow-up data was available for 20 cases with MIS-C and 28 cases with acute COVID-19. All patients (n = 15) who initially tested positive for SARS-CoV-2 IgG at admission remained positive serology during follow-up (100%). Among the 33 patients who initially tested negative, 12 (37.5%) showed a positive serology result during follow-up, while 21 (62.5%) remained negative. Within this subgroup, 11 cases (44%) were diagnosed with acute COVID-19, and one patient (12.5%) presented with MIS-C. Fourteen cases with acute COVID-19 infection (56%) and seven cases with MIS-C (87.5%) consistently showed negative serology results throughout the study. During follow-up, the median lymphocyte count demonstrated a significant difference, with 0.96 × 109 cells per L (IQR: 0.75-3.0 × 109 cells per L) in the SARS-CoV-2 IgG-negative group and 2.9 × 109 cells per L (IQR = 1.33-7.22 × 109 cells per L) in the SARS-CoV-2 IgG-positive group (p-value = 0.03). Patients who demonstrated seropositivity during the follow-up were associated with a notably severe disease (p-value = 0.028). Conclusion: Our study highlights the dynamic nature of SARS-CoV-2 IgG antibody responses in pediatric patients with COVID-19 infection. We observed a notable increase in seropositivity rates during follow-up. Furthermore, patients who were seropositive at follow-up demonstrated a severe disease course and lower lymphocyte counts compared to those with persistently negative serology. Our findings underscore the importance of longitudinal serological monitoring in understanding disease progression and immune response dynamics in pediatric COVID-19 cases.

Clinical and laboratory features of SARS-CoV-2 variants across multiple rounds of pandemic waves in hospitalized children in an Iranian referral hospital.

BACKGROUND: Since the onset of the COVID-19 pandemic, SARS-CoV-2 has evolved into independent new forms, variants of concern (VOCs). While epidemiological data showed increased transmissibility of VOCs, their impact on clinical outcomes is less clear. This study aimed to investigate the differences between the clinical and laboratory features of children infected with VOCs. METHODS: This study included all cases with SARS-CoV-2-positive nasopharyngeal swabs obtained from patients referred to Children's Medical Center (CMC), an Iranian referral hospital, between July 2021 and March 2022. The inclusion criteria for this study included all patients, regardless of age, who had a positive test anywhere in the hospital setting. Exclusion criteria for the study included those whose data was obtained from non-hospital outpatient settings, or referred from another hospital. The SARS-CoV-2 genome area encoding the S1 domain was amplified and sequenced. The type of variant in each sample was identified based on the mutations in the S1 gene. Demographic characteristics, clinical data, and laboratory findings were collected from the patient's medical records. RESULTS: This study included 87 pediatric cases with confirmed COVID-19, with a median age of 3.5 years (IQR: 1-8.12). Data from sequencing reveals the type of variants as 5 (5.7%) alpha, 53 (60.9%) Delta, and 29 (33.3%) Omicron. The incidence of seizure was higher in patients with Alpha and Omicron infection compared to the Delta group. A higher incidence of diarrhea was reported in Alpha-infected patients, and a higher risk of disease severity, distress, and myalgia was associated with Delta infection. CONCLUSION: Laboratory parameters did not mostly differ among the patients infected with Alpha, Delta, and Omicron. However, these variants may manifest different clinical features. Further studies with larger sample sizes are required to fully understand the clinical manifestations of each variant.

Multisystem inflammatory syndrome associated with SARS-CoV-2 infection in children: update and new insights from the second report of an Iranian referral hospital.

INTRODUCTION: Here, we are sharing our second report about children affected by Multisystem Inflammatory Syndrome in Children (MIS-C). The aim of the present study was to update our knowledge about children with MIS-C. Furthermore, we tried to compare clinical manifestations, laboratory features and final outcome of patients based on disease severity, in order to better understanding of the nature of this novel syndrome. METHODS: This retrospective study was conducted at Children's Medical Center Hospital, the hub of excellence in paediatrics in Iran, located in Tehran, Iran. We reviewed medical records of children admitted to the hospital with the diagnosis of MIS-C from July 2020 to October 2021. RESULTS: One hundred and twenty-two patients enrolled the study. Ninety-seven (79.5%) patients had mild to moderate MIS-C (MIS-C without overlap with KD (n = 80); MIS-C overlapping with KD (n = 17)) and 25 (20.5%) patients showed severe MIS-C. The mean age of all patients was 6.4 ± 4.0 years. Nausea and vomiting (53.3%), skin rash (49.6%), abdominal pain (46.7%) and conjunctivitis (41.8%) were also frequently seen Headache, chest pain, tachypnea and respiratory distress were significantly more common in patients with severe MIS-C (P < 0.0001, P = 0.021, P < 0.0001 and P < 0.0001, respectively). Positive anti-N severe acute respiratory syndrome coronavirus 2 IgM and IgG were detected in 14 (33.3%) and 23 (46.9%) tested patients, respectively. Albumin, and vitamin D levels in children with severe MISC were significantly lower than children with mild to moderate MIS-C (P < 0.0001, P = 0.05). Unfortunately, 2 (1.6%) of 122 patients died and both had severe MIS-C. CONCLUSION: Patients with MIS-C in our region suffer from wide range of signs and symptoms. Among laboratory parameters, hypoalbuminemia and low vitamin D levels may predict a more severe course of the disease. Coronary artery dilation is frequently seen among all patients, regardless of disease severity.

Hepatitis C infection in hemodialysis patients in Iran: a systematic review.

Hemodialysis (HD) patients are recognized as one of the high-risk groups for hepatitis C virus (HCV) infection. The prevalence of HCV infection varies widely between 5.5% and 24% among different Iranian populations. Preventive programs for reducing HCV infection prevalence in these patients require accurate information. In the present study, we estimated HCV infection prevalence in Iranian HD patients. In this systematic review, we collected all published and unpublished documents related to HCV infection prevalence in Iranian HD patients from April 2001 to March 2008. We selected descriptive/analytic cross-sectional studies/surveys that have sufficiently declared objectives, a proper sampling method with identical and valid measurement instruments for all study subjects, and proper analysis methods regarding sampling design and demographic adjustments. We used a meta-analysis method to calculate nationwide prevalence estimation. Eighteen studies from 12 provinces (consisting 49.02% of the Iranian total population) reported the prevalence of HCV infection in Iranian HD patients. The HCV infection prevalence in Iranian HD patients is 7.61% (95% confidence interval: 6.06-9.16%) with the recombinant immunoblot assay method. Iran is among countries with low HCV infection prevalence in HD patients.