The clinical relevance of performing a day seven post-operative absolute CD4 count in elective brain tumor surgery – A prospective cohort study from a single South African neurosurgical center

Introduction: The co-morbid presence of a neoplastic brain tumor, in a patient who is HIV positive, is not uncommon in South Africa. The day-7 post-operative absolute CD4 count offers a unique window into the immunological status of an individual post elective brain tumor surgery. Materials and methods: We performed a prospective cohort study consecutively enrolling all elective adult patients admitted tom our wards from the 01 July 2018–30 March 2020, with neoplastic brain tumors. In total 19 subjects that underwent elective operative intervention had a day seven post-operative absolute CD4 count performed. Data collected and analyzed in this study included age, HIV status, pre-operative corticosteroid therapy, pre-operative day CD4 count, timing of prophylactic antibiotic administration, craniotomy type, blood loss, duration of surgery, extent of resection, day seven post-operative CD4 count, post-operative corticosteroid therapy, histology, day-7 nosocomial infection incidence, Gram-stain result, and Glasgow Outcome Score. Results: Significance was demonstrated between the pre-operative day CD4 count and the day 7 post-operative CD4 count (p = 0.03). This allowed us to conclude the immunological impact of the surgery to have been insignificant. Significance was demonstrated between craniotomy type and day-7 post-operative CD4 count (p = 0.04). Significance was also demonstrated between extent of resection and the day-7 post-operative absolute CD4 count (p = 0.0018). A clinical trend was demonstrated for subjects with a lower day-7 post-operative CD4 count to have an increased risk of acquiring a day-7 nosocomial infection and a trend that this would be a Gram- negative infection. Conclusion: As per a PubMed review of the literature we are the first to report the relationship of the skull base surgical approaches, and a subtotal resection, and the statistically significantly delirious effect that these have on a day-7 absolute CD4 count. We further exclude increased intra-operative blood loss as an underlying cause behind the significance of these relationships.