Intracranial Empyemas in the COVID-19 Era: A New Phenomenon? A Paediatric Case Series and Review of the Literature

Abstract

Introduction We present the largest series of paediatric intracranial empyemas occurring after COVID-19 infection to date, and discuss the potential implications of the pandemic on this neurosurgical pathology. Methods Patients admitted to our centre between January 2016 and December 2021 with a confirmed radiological diagnosis of intracranial empyema were retrospectively reviewed, excluding non-otorhinological source cases. Patients were grouped according to onset before or after onset of the COVID-19 pandemic, and COVID-19 status. A literature review of all post-COVID-19 intracranial empyemas was performed. SPSS v27 was used for statistical analysis. Results 16 patients were diagnosed with intracranial empyema: n=5 prior to 2020 and n=11 after, resulting in an average annual incidence of 0.3% prior to onset of the pandemic and 1.2% thereafter. Of those diagnosed since the pandemic, 4 (25%) were confirmed to have COVID-19 on recent PCR test. Time from COVID-19 infection until empyema diagnosis ranged from 15 days to 8 weeks. Mean age for post-COVID-19 cases was 8.5 years (range: 7-10 years) compared to 11 years in non-COVID cases (range: 3-14 years). Streptococcus intermedius was grown in all cases of post-COVID-19 empyema and 3 of 4 (75%) post-COVID-19 cases developed cerebral sinus thromboses, compared to 3 of 12 (25%) non-COVID-19 cases. All cases were discharged home with no residual deficit. Conclusion Our post-COVID-19 intracranial empyema series demonstrates a greater proportion of cerebral sinus thromboses than non-COVID-19 cases, potentially reflecting the thrombogenic effects of COVID-19. Incidence of intracranial empyema at our centre has increased since the start of the pandemic, causes of which require further investigation and multicentre collaboration.

The association of COVID-19 pandemic with the increase of sinogenic and otogenic intracranial infections in children: a 10-year retrospective comparative single-center study

“…In the field of otorhinolaryngology, studies have reported a reduced number of otogenic and sinogenic infections [ 10 , 17 , 19 , 23 ]. Despite the decline in infection cases, recent case reports and clinical studies have identified a worrisome trend of increased severity in sinusitis and otitis media among children, resulting in multiple intracranial complications including extensions of epidural and subdural infections, as well as cerebral venous sinus thrombosis [ 1 , 2 , 5 , 13 , 14 , 18 , 20 , 25 , 26 ]. In our study, we observed a sudden increase in intracranial infections of otogenic origin after the beginning of the pandemic (3 cases versus no cases before the pandemic over the observational period of our study), while those of sinogenic origin remained comparably stable.…”

“…Similar to our study, 73% of the COVID-19 cases were associated with sinusitis, with Streptococcus intermedius being the most commonly cultured species. In the long-term follow-up, all patients recovered without any limitations [ 13 ].…”

Intracranial complications of sinogenic and otogenic infections in children: an ESPN survey on their occurrence in the pre-COVID and post-COVID era

“…This theory is supported by the evidence of two factors potentially favoring the bacterial penetration in adults: the inflammation of the respiratory tract mucosa and the circulation of COVID DNA and lipopolysaccharide in the plasma [ 37 , 38 ]. Nevertheless, the role of COVID-19 in favoring the bacterial penetration in the central nervous system still remains unproved in children [ 21 , 22 ]. The second hypothesis concerns the impairment of the respiratory microbiota.…”

“…However, several studies showed that COVID infection itself is associated with a risk of venous sinus thrombosis, probably because of the hypercoagulability induced by COVID-19, resulting in a significant mortality rate (about 36%) [ 74 , 75 ]. Based on their data of 75% of children with venous sinus thrombosis among those with intracranial empyema and recent COVID infection (3 out of 4 cases) versus 25% of children without COVID infection (3 out of 12 cases), Hall et al postulated a concurrent role of COVID infection in inducing sinus venous thrombosis in this subset of patents [ 22 ]. The present survey does not confirm this data in a large number of cases.…”

“…The goal of the study provided by Hall and coworkers was to assess the possible relationship between COVID-19 infection and occurrence of intracranial empyema by retrospectively reviewing all intracranial empyema cases from 2016 to 2021 [ 22 ]. Overall, they found 16 cases, 6 of them belonging to the 2016–2019 period (incidence of 1.25 cases/year, 0.3% of all period-related surgical admissions) and 11 of them belonging to the 2020–2021 period (5.5 cases/year, 1.2% of all admissions).…”