Causes and Follow-Up of Central Diabetes Insipidus in Children

Abstract

Objective: To identify the causes of central diabetes insipidus (CDI) by evaluating the values of magnetic resonance imaging (MRI) in the diagnosis of pediatric CDI, providing evidence for the clinical diagnosis and treatment of CDI.

Methods: Seventy-nine patients with CDI (CDI group) hospitalized from July 2012 to March 2017 and 43 healthy children (control group) were enrolled in this study. All cases underwent MRI examination including T1-weighted three-dimensional magnetization-prepared rapid gradient-echo (T1WI-3D-MP RAGE) imaging sequences. The pituitary volume, the signal intensity of posterior pituitary, and the morphology of pituitary stalk were measured between two groups. The medical history, urine testing, imaging of hypothalamic-pituitary region, and hormone levels were also recorded.

Results: Age and gender were matched between the CDI and control groups. The height and BMI in the CDI group were less and the urine volume in 24 h was higher than those in the control group. The signal intensity of the posterior pituitary was higher in the control group, whereas the pituitary volume was smaller in the CDI group. In the CDI group, 44 cases presented with morphological changes of the pituitary stalk. Clinical symptoms mainly included polydipsia, polyuria, short stature, and vomiting. All patients were confirmed by water deprivation vasopressin test. Forty-four CDI children were associated with hypopituitarism, including 33 cases of PSIS with multiple pituitary hormone deficiencies (MPHD) and 11 cases of growth hormone deficiency (IGHD). The pituitary volume in the cases of pituitary stalk interruption syndrome (PSIS) with MPHD was smaller than that in the IGHD patients.

Conclusions: The signal intensity ratio of the posterior lobe, pituitary volume, and the morphology of pituitary stalk on T1WI-3D-MP RAGE image contribute to the diagnosis of CDI.

Figure 1

Etiological classification of CDI. Craniopharyngioma: (a) T1WI image showed tumor (white arrowhead); (b) 3D examination showed clearer uniform tumor (white arrow). Intracranial germinoma: (c) T1WI image showed that the upper edge of the pituitary was uplifted, and the posterior high signal was not shown, and the pituitary stalk was thickened (white arrow); (d) the enhanced examination showed that the pituitary stalk and pineal gland were uniformly nodular (white arrows). Langerhans cell histiocytosis: (e) T1WI showed a thickening of the pituitary stalk, showing T1 and other T2 signals, clear edges, pressure in the third ventricle, disappearance of the funnel crypt, slightly increased pressure in the optic chiasm, and no signal in the posterior pituitary; (f) the enhanced scan showed mild even enhancement of the mass, and the anterior pituitary was less clear.

Figure 2

Measurement of the posterior pituitary signal intensity. (a) The signal intensity of the posterior pituitary of the normal pituitary was higher than that of the pons. (b) The high signal of the posterior pituitary (white arrow) contrasts with the anterior pituitary and the pons.

Figure 3

Pituitary stem blockage syndrome. (a) T1WI showed that the anterior pituitary was thin, the central site was sunken, the posterior pituitary high signal was not clearly shown, and the pituitary stalk was interrupted (white arrow). (b) The enhanced examination showed a small ectopic position in the anterior pituitary and after the optic chiasm, and obvious uniform enhancement was found in the posterior leaves. (c) T1WI showed that high intensity of posterior pituitary was disappeared and the pituitary stalk showed a thin line. (d) The enhanced examination showed anterior pituitary atrophy.