High CSF transforming growth factor beta levels after subarachnoid haemorrhage: association with chronic communicating hydrocephalus

Abstract

Background: Chronic communicating hydrocephalus is a common sequela of subarachnoid haemorrhage and develops when the flow and drainage of CSF are impaired after fibrosis in the subarachnoid space. Released by platelets into the CSF after subarachnoid haemorrhage, transforming growth factor (TGF)beta1/beta2 are potent fibrogenic agents that may promote post-haemorrhagic fibrosis and chronic communicating hydrocephalus.

Methods: Temporal changes in total (latent plus active) TGFbeta1/beta2 CSF levels of post-haemorrhage patients developing acute hydrocephalus were measured using ELISA to discover if titres were higher in patients that subsequently developed chronic communicating hydrocephalus, compared with those that did not.

Results: Mean (SD) CSF levels of total TGFbeta1 were 97 (42) pg/ml and total TGFbeta2 were 395 (39) pg/ml in control patients with (non-haemorrhagic) hydrocephalus. For days 1-5 post-subarachnoid haemorrhage (dph), levels of 1427 (242) pg/ml and 976 (191) pg/ml were seen for total TGFbeta1 and TGFbeta2, respectively. Beyond 5 dph, total TGFbeta1/beta2 levels declined but remained significantly elevated (p<0.01) above control patient values for at least 19 dph. Haemorrhagic patients that went on to develop chronic communicating hydrocephalus had significantly higher levels of total TGFbeta1 (p<0.01) and TGFbeta2 (p<0.05) between 1 and 9 dph, compared with those of haemorrhagic patients that did not.

Conclusions: Acutely measured levels of TGFbeta1/beta2 in the CSF of patients with subarachnoid haemorrhage are thus potential prognostic biomarkers for the subsequent development of chronic communicating hydrocephalus, indicating likely dependency on CSF shunting.