MR imaging of the posterior hypophysis in children with tuberculous meningitis

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) contributes to the morbidity and mortality in children with tuberculous meningitis (TBM). MRI assists in the early diagnosis of TBM and absence of the normal posterior pituitary bright spot (PPS) on T1-weighted MRI in TBM may indicate the functional integrity of the posterior hypophysis. The objective of this retrospective descriptive study of 22 children with TBM was to determine the prevalence of an absent PPS on T1-weighted MRI in children with TBM and its correlation with serum sodium levels (hyponatremia), severity of disease at presentation, and developmental outcome after 6 months. The prevalence of absent PPS in children with TBM was 55%. No significant correlation was found between the PPS and serum sodium status (p = 0.41) or severity of disease at presentation (p = 0.104). There was however a correlation between absent PPS and poorer developmental outcome at 6-month follow-up (p = 0.027).