Saliva and bloodspot cortisol: novel sampling methods to assess hydrocortisone replacement therapy in hypoadrenal patients

BACKGROUND: In patients with hypoadrenalism, it is often difficult to assess the optimal dose of glucocorticoid replacement. Serial serum cortisol measurements for a cortisol day curve are sometimes used, but this has low acceptability for patients. In this study, we evaluate the reliability of saliva and capillary bloodspot cortisol as alternative methods in assessing cortisol profiles in hypoadrenal patients on hydrocortisone replacement. METHODS: We first examined the correlations between serum cortisol, saliva and bloodspot cortisol in in-hospital patients not on glucocorticoid therapy. We then studied 18 hypoadrenal patients on hydrocortisone therapy and measured their serum, saliva and bloodspot cortisol concurrently at seven different time points in a single day. RESULTS: For in-hospital patients, a significant correlation exists between saliva and serum cortisol (R = 0.7121, P < 0.0001), but there is a stronger correlation between bloodspot and serum cortisol (R = 0.9494, P < 0.0001). The correlations were weaker in hypoadrenal patients on hydrocortisone (saliva and serum cortisol: R = 0.6262, P < 0.001; bloodspot and serum cortisol: R = 0.7871, P < 0.001). When we evaluated each measurement with respect to an arbitrary target range, there was a greater degree of agreement between serum and capillary bloodspot cortisol (85% agreement) than between serum and saliva cortisol (65% agreement) (P < 0.001). CONCLUSION: Bloodspot samplings provide a simple and convenient way for ambulant hypoadrenal patients on hydrocortisone replacement therapy to assess cortisol levels at multiple times in a single day. This may be useful in determining the optimal glucocorticoid dose for hypoadrenal patients.     

Thalamic reductions in children with chromosome 22q11.2 deletion syndrome

Children with chromosome 22q11.2 deletion syndrome (22q) suffer from physical and behavioral dysfunctions, including neuroanatomical anomalies, visuo-spatial processing deficits, and increased risk for psychopathology. Reduced total brain volume, parietal lobe volume, and cerebellar volumes, enlarged ventricles, and increased basal ganglia volumes have been reported. Since previous literature has related the pulvinar nucleus of the thalamus to visuo-spatial processing, we compared the thalamic volume in children with 22q to typically developing controls. Children with 22q showed a significant reduction of the thalamus compared with normally developing children, specifically in the posterior portion of the thalamus, including the pulvinar nucleus. These results provide the first evidence for a potential relationship between posterior thalamic reductions and the characteristic visuo-spatial deficits demonstrated in this group.     

Catastrophic presentation of mitochondrial disease due to a mutation in the tRNA(His) gene

The authors describe a patient who presented with headache, seizures, and severe cerebral edema in whom they identified a novel mutation in the mitochondrial (mt-) tRNA(His) gene. This G12147A transition is heteroplasmic, predicted to disrupt a highly conserved base pair, and segregates with the cytochrome c oxidase deficiency in single muscle fibers.     

Computational models of the basal ganglia: from robots to membranes

With the rapid accumulation of neuroscientific data comes a pressing need to develop models that can explain the computational processes performed by the basal ganglia. Relevant biological information spans a range of structural levels, from the activity of neuronal membranes to the role of the basal ganglia in overt behavioural control. This viewpoint presents a framework for understanding the aims, limitations and methods for testing of computational models across all structural levels. We identify distinct modelling strategies that can deliver important and complementary insights into the nature of problems the basal ganglia have evolved to solve, and describe methods that are used to solve them.     

Pediatric thoracic lymphangiomatosis: is chest wall resection too radical?

Lymphangiomas account for 5% to 6% of all pediatric neoplasms. Complex pathologic processes often present a diagnostic and treatment challenge. Radical and major surgery might have a role in complex cases when medical treatment fails.     

Palliative care research protocols: a special case for ethical review?

Between October 2001 and May 2002 the Chairperson and Vice-Chairperson of each Multicentre Research Ethics Committee (MREC) in England, Wales and Scotland took part in a semi-structured interview to ascertain the attitudes of MRECs to palliative care research. Interviews were transcribed and analysed using a grounded theory approach. Most respondents said each protocol was reviewed on its own merits, according to broad ethical principles, but were equivocal as to whether palliative care protocols posed particular or different challenges compared to those from other specialties. Respondents said they reviewed only a small number of palliative care protocols, and that they were less experienced with some of the study methods utilized, particularly qualitative designs. Four main themes emerged from the analysis. Respondents expressed concerns about the protocol itself--in regard to safeguarding the principles of autonomy and justice. There were concerns about how the research would be carried out, especially the protection of patients and the influence and input of the researcher in the process. The third theme concerned the impact of the research on the participant, particularly intrusion, potential distress and the existence of support mechanisms. Fourthly, respondents identified patient groups receiving palliative care (children, the elderly, bereaved families, patients in intensive therapy units, and those from ethnic groupings), who they considered might be particularly vulnerable.