Diabetes Insipidus Clinical Presentation

Updated: Feb 21, 2018
  • Author: Romesh Khardori, MD, PhD, FACP; Chief Editor: George T Griffing, MD  more...
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Polyuria, polydipsia, and nocturia are the predominant manifestations of diabetes insipidus (DI). The daily urine volume is relatively constant for each patient but is highly variable between patients, ranging from 3-20 L.

A patient’s history may indicate whether he/she has central or nephrogenic DI. The most common form of DI is central DI following trauma or surgery to the region of the pituitary and hypothalamus. It may exhibit 1 of 3 patterns: transient, permanent, or triphasic. The triphasic pattern is observed more often clinically. Whether improvements in surgical techniques and approaches have altered the frequency of the triphasic pattern is not well studied.

The first phase of the triphasic pattern is a polyuric one that lasts 4-5 days, caused by inhibition of antidiuretic hormone (ADH). An immediate increase in urine volume and a concomitant fall in urinary osmolality occur. The second phase is an antidiuretic one that lasts 5-6 days, resulting from the release of stored hormone; urinary osmolality rises. The third phase can be permanent DI, when stores of ADH are exhausted and the cells that produce ADH are absent or unable to produce more.

In infants with DI, the most apparent signs may be the following:

  • Crying
  • Irritability
  • Growth retardation
  • Hyperthermia
  • Weight loss

In children, the following manifestations typically predominate:

  • Enuresis
  • Anorexia
  • Linear growth defects
  • Fatigability

Pregnancy is associated with an increased risk of DI, but this form remits after delivery. In addition, pregnancy may unmask subclinical or mild central DI. DI complicates about 1 in 30,000 pregnancies. [23] (See Pituitary Disease and Pregnancy.)

In mentally intact patients, thirst is the most sensitive indicator of water balance. Many patients have a predilection for drinking cold liquids, often water. Neurologic symptoms vary with the patient’s access to water; patients with free access may have no neurologic symptoms at all. However, the clinical presentation depends on the cause and severity, as well as on the patient’s associated medical condition(s).

Rarely, patients present with adipsic DI. This usually implies a lesion affecting ADH production and the hypothalamic osmoreceptor. Patients with adipsic DI are at much higher risk of severe dehydration and may require prescriptive fluid replacement regimes.

If the condition that caused DI also damaged the anterior pituitary or hypothalamic centers that produce releasing factors, patients may present with other symptoms and signs of anterior pituitary dysfunction. These would include excessive fatigue, diminished libido or erectile dysfunction, headache, dry skin, and hair loss.

A study by Masri-Iraqi et al suggested that anterior pituitary dysfunction occurs in the majority of adults with central DI. The investigators found that in 73% of the study’s subjects, which consisted of 70 adults with central DI, one or more anterior pituitary axes were affected. [24]


Physical Examination

The physical examination findings vary with the severity and chronicity of DI. The examination findings may be entirely normal. Hydronephrosis, with pelvic fullness, flank pain or tenderness, or pain radiating to the testicle or genital area, may be present. Bladder enlargement occurs in some patients. Unless the thirst mechanism is impaired or access to fluid is restricted, dehydration is not seen. Aside from an enlarged bladder, no specific signs of DI exist.