The significance of protein S-100B testing in cardiac arrest patients

S100B protein in serum is elevated after global cerebral ischemic injury

BACKGROUND:

S100B protein in patients with cardiac arrest, hemorrhagic shock and other causes of global cerebral ischemic injury will be dramatically increased. Ischemic brain injury may elevate the level of serum S100B protein and the severity of brain damage.

METHODS:

This article is a critical and descriptive review on S100B protein in serum after ischemic brain injury. We searched Pubmed database with key words or terms such as “S100B protein”, “cardiac arrest”, “hemorrhagic shock” and “ischemia reperfusion injury” appeared in the last five years.

RESULTS:

S100B protein in patients with cardiac arrest, hemorrhagic shock and other causes of ischemic brain injury will be dramatically increased. Ischemic brain injury elevated the level of serum S100B protein, and the severity of brain damage.

CONCLUSION:

The level of S100B protein in serum is elevated after ischemic brain injury, but its mechanism is unclear.

A lack of association between elevated serum levels of S100B protein and autoimmunity in autistic children

BACKGROUND

S100B is a calcium-binding protein that is produced primarily by astrocytes. Increased serum S100B protein levels reflect neurological damage. Autoimmunity may have a role in the pathogenesis of autism in some patients. Autoantibodies may cross the blood-brain barrier and combine with brain tissue antigens, forming immune complexes and resulting in neurological damage. We are the first to investigate the relationship between serum levels of S100B protein, a marker of neuronal damage, and antiribosomal P protein antibodies in autistic children.

METHODS

Serum S100B protein and antiribosomal P antibodies were measured in 64 autistic children in comparison to 46 matched healthy children.

RESULTS

Autistic children had significantly higher serum S100B protein levels than healthy controls (P < 0.001). Children with severe autism had significantly higher serum S100B protein than patients with mild to moderate autism (P = 0.01). Increased serum levels of antiribosomal P antibodies were found in 40.6% of autistic children. There were no significant correlations between serum levels of S100B protein and antiribosomal P antibodies (P = 0.29).

CONCLUSIONS

S100B protein levels were elevated in autistic children and significantly correlated to autistic severity. This may indicate the presence of an underlying neuropathological condition in autistic patients. Antiribosomal P antibodies may not be a possible contributing factor to the elevated serum levels of S100B protein in some autistic children. However, further research is warranted to investigate the possible link between serum S100B protein levels and other autoantibodies, which are possible indicators of autoimmunity to central nervous system in autism.

Serum levels of protein S100B predict intracranial lesions in mild head injury

OBJECTIVES

This study was aimed to assess whether serum S100B levels at emergency department admission can be used to omit unnecessary computed tomography (CT) in patients with minor head injury (MHI).

DESIGN AND METHODS

Sixty consecutive patients with recent MHI were included in this study. Serum S100B measurement and CT scanning were performed in all patients within 3h from head injury.

RESULTS

A positive CT scan was present in 20 out of 60 subjects. Significantly higher values of protein S100B were found in CT positive than in CT negative patients (1.35 versus 0.48 μg/L; p<0.001). The area under the ROC curve for protein S100B was highly significant (AUC 0.80; p<0.001) and a S100B cut-off value of 0.38 μg/L displayed 100% sensitivity and 58% specificity.

CONCLUSIONS

Serum S100-B levels might allow to omit unnecessary CT in patients with pure MHI, thus reducing radiation exposure and saving healthcare resources.