1. Diabetes insipidus: Differential diagnosis and management
Gary L. Robertson, MD 
Best Practice & Research Clinical Endocrinology & Metabolism 
Volume 30, Issue 2, Pages (March 2016)
DOI: /j.beem
Copyright © 2016 Elsevier Ltd Terms and Conditions

2. Fig. 1
Relation of plasma AVP to plasma and urine osmolarity in patients with different types of DI. Open and closed squares indicate partial or severe pituitary DI. Open or closed triangles indicate partial or severe nephrogenic DI. Closed circles indicate primary polydipsia.
Best Practice & Research Clinical Endocrinology & Metabolism  , DOI: ( /j.beem )
Copyright © 2016 Elsevier Ltd Terms and Conditions

3. Fig. 2
Urine osmolarity under basal conditions, during a dehydration test and after administration of AVP or desmopressin (DDAVP) in patients with primary polydipsia, acquired or familial pituitary DI and acquired or familial nephrogenic DI. The shaded boxes indicate the values in healthy adults under the same three conditions.
Best Practice & Research Clinical Endocrinology & Metabolism  , DOI: ( /j.beem )
Copyright © 2016 Elsevier Ltd Terms and Conditions

4. Fig. 3
Algorithm for differential diagnosis of DI by modified fluid deprivation test.
Best Practice & Research Clinical Endocrinology & Metabolism  , DOI: ( /j.beem )
Copyright © 2016 Elsevier Ltd Terms and Conditions

5. Fig. 4
Algorithm for differential diagnosis of DI by plasma AVP-MRI method.
Best Practice & Research Clinical Endocrinology & Metabolism  , DOI: ( /j.beem )
Copyright © 2016 Elsevier Ltd Terms and Conditions

6. Fig. 5
T-1 weighted mid-saggital MR images in patients with different types of DI. Note that the hyperintense signal normally emitted by the posterior pituitary is absent in pituitary DI (A), faint in nephrogenic DI (B) and present in primary polydipsia (C).
Best Practice & Research Clinical Endocrinology & Metabolism  , DOI: ( /j.beem )
Copyright © 2016 Elsevier Ltd Terms and Conditions

7. Fig. 6
Effect of desmopressin therapy in 3 adults with different types of DI. The left panel (A) is a patient with partial pituitary DI. The middle panel (B) is partial nephrogenic DI. The right panel (C) is a patient with the dipsogenic form of primary polydipsia. The shaded bars indicate urine volume and the open bars fluid intake in mL/8 h. The shaded triangles show the osmolarity of each 8 h urine collection. The black circles indicate the plasma sodium concentration at the beginning of each collection period. The stippled boxes at the top indicate the period of desmopressin therapy, 200 μg by mouth every 8 h. The box labeled FR in panel C indicates fluid restriction. In all 3 patients, fluid intake tended to be higher than urine volume due to insensible water loss. In the patient with pituitary DI, desmopressin normalized urine osmolarity and volume within 8 h. At the same time, it also reduced thirst and fluid intake but the decrease was smaller than urine output. Consequently, body water increased and plasma sodium fell, suppressing thirst and water intake to bring it into balance with urine output and stabilize plasma sodium within the normal range. In the patient with nephrogenic DI, desmopressin had no appreciable effect on any of these variables. In dipsogenic DI, desmopressin also normalized urine osmolarity and volume within 8 h but the reduction in thirst and fluid intake was smaller and remained relatively high for the next 32 h, resulting in progressive water retention and the development of hyponatremia that was corrected by discontinuing desmopressin and restricting fluid intake (RFI).
Best Practice & Research Clinical Endocrinology & Metabolism  , DOI: ( /j.beem )
Copyright © 2016 Elsevier Ltd Terms and Conditions