title: Crystals seen on CSF microscopy in a case of suspected subarachnoid haemorrhage.
abstract: Although crystals are rarely identified on cerebrospinal fluid (CSF) microscopy, their presence can be of significant diagnostic value. We report a case of oxalate crystals seen on CSF microscopy of a 43-year-old woman. The patient presented with headaches, nausea and vomiting. CT of the head showed a small focus of hyper-density, suspicious of haemorrhage, in the right side of the pontine cistern. CSF cell count was within the normal range. Although no organisms were seen on microscopy, copious oxalate crystals were seen. The same crystals were seen on microscopy of CSF collected in a fluoride oxalate container used for glucose analysis. A follow-up contrast-enhanced CT angiogram did not demonstrate any abnormalities. It transpired that excess CSF had been collected into a fluoride oxalate container. This had subsequently been decanted into a plain container for microbiological analysis. Correct specimen collection should be emphasised when teaching lumbar puncture technique.
authors.affiliation: Department of Medical Microbiology, Hull Royal Infirmary, Hull, East Riding of Yorkshire, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: Weiand
authors.affiliation: Department of Clinical Biochemistry, Hull Royal Infirmary, Hull, East Riding of Yorkshire, UK.
authors.forename: Ian
authors.initials: I
authors.lastname: Hanning
authors.affiliation: Department of Neurology, Hull Royal Infirmary, Hull, East Riding of Yorkshire, UK.
authors.forename: Moussa
authors.initials: M
authors.lastname: Mouhamadou
authors.affiliation: Department of Medical Microbiology, Hull Royal Infirmary, Hull, East Riding of Yorkshire, UK.
authors.forename: Debbie
authors.initials: D
authors.lastname: Wearmouth
mesh_terms: D000328:Adult; D002129:Calcium Oxalate / Q000134:cerebrospinal fluid*; D003460:Crystallization; D005260:Female; D006261:Headache / Q000134:cerebrospinal fluid* / Q000000981:diagnostic imaging / Q000209:etiology; D006801:Humans; D008853:Microscopy / Q000379:methods*; D011859:Radiography; D013048:Specimen Handling; D013129:Spinal Puncture / Q000379:methods*; D013345:Subarachnoid Hemorrhage / Q000134:cerebrospinal fluid* / Q000000981:diagnostic imaging
chemical_list: D002129:Calcium Oxalate