October 17, 2014
Hypoglycorrhachia is defined as an abnormally low glucose concentration within the cerebrospinal fluid is often suggestive of an underlying infectious or systemic process. This is often defined as a glucose concentration less than 40 mg/dL. As well, under homeostatic conditions, the CSF/serum glucose ratio should be > 0.6. In certain cases, hypoglycorrhachia with a CSF/serum ratio > 0.6 can be secondary to systemic hypoglycemia and must be considered in the differential when evaluating this finding. In a retrospective analysis of patients with hypoglycorrhachia, infectious etiologies such bacterial, viral or fungal meningitis were most common. In fact, up to one quarter of patients had a definitive diagnosis of bacterial meningitis. However, up to one third of patients may have a non-infectious etiology that may include malignancy, stroke/hemorrhage, autoimmune processes, or more rare transport deficiencies.
- Chow E and Troy SB. The Differential Diagnosis of Hypoglycorrhachia in Adult Patients. The American Journal of the Medical Sciences. 2013; 0: 1-5.
- Leen WG et al. Child Neurology: Differential Diagnosis of low CSF glucose in children and young adults. Neurology. 2013; 81: e178-e181.
Submitted by James Addington, MD, Resident Physician, Department of Neurology University of Virginia