Effect of different management strategies on outcomes in subarachnoid neurocysticercosis: a descriptive, multicentre, retrospective cohort study in the USA

Background: infection. There is limited evidence to guide clinical management. We aimed to describe the clinical and laboratory features of a cohort of patients with SANCC, and assess the impact of different management strategies on their clinical course. Methods: antigen or qPCR and negativity to viral, fungal, and bacterial pathogens. Each site reported up to the most recent 7 sequential patients with SANCC based on institutional memory or systematic searching of the electronic medical records. Data entry was performed from Nov 12, 2021 to Nov 28, 2022. Minimal criteria for inclusion was a discharge summary for a hospitalisation due to SANCC. Data collection centred around the earliest hospitalisation associated with the SANCC. Data from prior and subsequent inpatient and outpatient visits were also collected. Data were analysed to assess the impact of treating with anthelmintics based on CSF biomarkers, the normalisation of imaging, or a fixed duration on SANCC recurrence rates. Diagnostic delay was defined as patients with prior hospitalisation or extensive workup for a complication (e.g. stroke, hydrocephalus, meningitis, mass) but without SANCC suspected. Those with a diagnostic delay and those with a diagnosis of SANCC but were initially managed without anthelmintics (e.g. shunt, cyst removal) were considered to have a delay in anthelmintic treatment. The effect of delay in anthelmintic treatment on subsequent Emergency Room visits and hospitalisations was assessed. Findings: biomarkers (antigen [TsAg] and/or qPCR) to guide length of anthelmintic therapy decreased SANCC recurrence (0 [n = 0 of 17] vs. 23% [n = 8 of 33], p = 0.039, odds ratio [OR] 95% confidence interval [CI] 0.0-0.84), whereas use of magnetic resonance imaging normalisation to guide treatment length did not decrease recurrence (15% [n = 3 of 20] vs 16.67% [n = 5 of 30] p > 0.9, OR 95% CI 0.21-4.18). A delay in anthelmintic treatment was associated with an increase in subsequent SANCC-related Emergency Department visits or hospital admissions (median 1, IQR 1-2) compared to no anthelmintic delay (median 0.5, IQR 0-1; p = 0.018). Interpretation: SANCC is commonly misdiagnosed and diagnostic and therapeutic delays may lead to more subsequent hospital encounters for SANCC-related problems. Use of CSF Ts biomarkers to guide anthelmintic therapy may decrease SANCC recurrence. However, given the small sample size, adjustment for confounders with regression analysis was not performed and we cannot exclude confounding as responsible for differences seen. Larger, prospective studies are needed to confirm these findings. Funding: Division of Intramural Research, National Institute of Allergy and Infectious Diseases.