Does pituitary tumour apoplexy have an infective aetiology?

Pituitary apoplexy is a life-threatening acute medical emergency, secondary to the sudden haemorrhage and/or infarction of a pre-existing pituitary adenoma. It is estimated to affect between 2-7% of pituitary adenomas and patients usually present with sudden headache, visual disturbance and altered mental status which if untreated, can result in death. Several factors have been implicated with apoplexy, including use of anti-coagulants, prior major surgery and pregnancy. Despite this, in excess of 50% of patients present suddenly with no recognised precipitating factor and as such, a stratified approach to patient management is difficult with regards to this acute clinical syndrome.

Anatomically, the human pituitary gland is positioned at the base of the brain and housed directly above the sphenoid sinus in a small bony cavity called the sella turcica. Previous studies by our group and others have noted thickening of the sphenoid sinus mucosa in 64-89% of patients in the acute of phase of pituitary apoplexy [1]. In order to investigate a microbial cause, preliminary work has used PCR-cloning to identify Enterobacteriaceae from the sinuses of apoplexy patients (n=5). These organisms were not detected in the sphenoid samples of non-apoplectic controls.

The aim of this study is to investigate the microbiology of the sphenoid sinus and pituitary gland in pituitary apoplexy patients in comparison to non-apoplectic controls. For this we aim to employ a combination of imaging techniques (fluorescent in-situ hybridisation), next generation sequencing (MiSeq) and immunohistochemistry. Later stages of this project may involve the development of microcosm systems broadly representative of the sphenoid sinus for the investigation of bacterial population dynamics in vitro.

The successful candidate will be trained in-house in a range of microbiological techniques, including the analysis of next generation sequencing data (QIIME, Phyloseq). The candidate may also contribute to the development of ethics applications for the collection of tissue samples. Laboratory based work will be undertaken at the University of Manchester, Stopford Building and as such, the student will have access to the world leading facilities available at this institution.

Candidates are expected to hold a minimum upper-second (or equivalent) undergraduate degree in a related biomedical/biological science such as Microbiology or a closely related field. A Masters qualification in a similar area would be highly desirable.