High opening pressure at lumbar puncture (LP) (spinal tap) is recognised as a poor prognostic feature of cryptococcal meningitis. For these patients repeated LP is advocated, including the use of lumbar drains or ventricular shunts in some cases.
In a provocative paper from Uganda, Rolfes and colleagues found that at least one ‘therapeutic’ LP for high opening pressure or a change in clinical status reduced death significantly, regardless of the actual opening pressure. 75 (30%) individuals had at least one therapeutic LP and only 5 deaths (7%) occurred in this group compared with 31 deaths (18%) occurred among 173 individuals without a therapeutic LP. The adjusted relative risk of mortality was 0.31 (95% confidence interval: 0.12-0.82). Those individuals receiving therapeutic LPs were in a poorer prognostic group, having higher CSF opening pressures, higher CSF fungal burdens, and were more likely to have altered mental status at baseline than those with no therapeutic LPs.
While these data are not definitive, second and third LPs early after diagnosis may improve outcome. The reason for improvement after LP is not clear. However LPs are labour intensive and require considerable skill. In regions with high numbers of cryptococcal meningitis patients, follow up LPs on everyone with this diagnosis will layer another burden on top of already struggling health services.Definitive guidance is important and will require additional study.