Transient diabetes insipidus during pregnancy: a clinical case and a review of the syndrome

Pregnancy-associated diabetes insipidus in Japan-a review based on quoting from the literatures reported during the period from 1982 to 2019

This Review Article overviews the literature on diabetes insipidus (DI) associated with pregnancy and labor in Japan published from 1982 to 2019. The total number of patients collected was 361, however, only one-third of these cases had detailed pathophysiologic information enabling us to identify the respective etiology and subtype. Pregnancy-associated DI can be divided into 3 etiologies, central (neurogenic) DI, nephrogenic DI, and excess vasopressinase-associated DI. Neurogenic DI has various causes: for example, DI associated with tumoral lesions in the pituitary and neighboring area, DI associated with Sheehan's syndrome and/or pituitary apoplexy, and DI associated with lymphocytic infundibuloneurohypophysitis (LINH, stalkitis). Nephrogenic DI results from defective response of the kidney to normal levels of vasopressin. However, the most interesting causal factor of pregnancy-associated DI is excess vasopressinase, caused either by excess production of vasopressinase by the placenta or defective clearance of vasopressinase by the liver. Hepatic complications resulting in pregnancy-associated DI include acute fatty liver of pregnancy (AFLP) and HELLP syndrome (syndrome of hemolysis, elevated liver enzymes, low platelets), as well as pre-existing or co-incidental hepatic diseases. A possible role of glucose uptake in putative stress-induced DI and the importance of correct diagnosis and treatment of pregnancy-associated DI, including use of 1-deamino 8-D arginine vasopressin, are also discussed.

Gestational diabetes insipidus: Diagnosis and management

In the pregnant patient, hypotonic polyuria in the setting of elevated serum osmolality and polydipsia should narrow the differential to causes related to diabetes insipidus (DI). Gestational DI, also called transient DI of pregnancy, is a distinct entity, unique from central DI or nephrogenic DI which may both become exacerbated during pregnancy. These three different processes relate to vasopressin, where increased metabolism, decreased production or altered renal sensitivity to this neuropeptide should be considered. Gestational DI involves progressively rising levels of placental vasopressinase throughout pregnancy, resulting in decreased endogenous vasopressin and resulting hypotonic polyuria worsening through the pregnancy. Gestational DI should be distinguished from central and nephrogenic DI that may be seen during pregnancy through use of clinical history, urine and serum osmolality measurements, response to desmopressin and potentially, the newer, emerging copeptin measurement. This review focuses on a brief overview of osmoregulatory and vasopressin physiology in pregnancy and how this relates to the clinical presentation, pathophysiology, diagnosis and management of gestational DI, with comparisons to the other forms of DI during pregnancy. Differentiating the subtypes of DI during pregnancy is critical in order to provide optimal management of DI in pregnancy and avoid dehydration and hypernatremia in this vulnerable population.

Other Pituitary Conditions and Pregnancy

Diagnosis of lymphocytic hypophysitis occurring in the peripartum period is based on clinical and neuroradiological data and does not require a biopsy. Its course is generally spontaneously favorable in terms of mass effect but may require the administration of corticosteroids or even transsphenoidal resection. The course of pituitary deficiencies is highly variable; some cases recover over time, whereas others persist indefinitely. Sheehan syndrome is very rare in developed countries. Because agalactia and amenorrhea are often neglected, the diagnosis is generally delayed. Diabetes insipidus occurring in late pregnancy is caused by the increased placental production of vasopressinase and disappears after delivery.

Diabetes insipidus during pregnancy

Diabetes insipidus (DI) in pregnancy is a heterogeneous syndrome, most classically presenting with polyuria and polydipsia that can complicate approximately 1 in 30,000 pregnancies. The presentation can involve exacerbation of central or nephrogenic DI during pregnancy, which may have been either overt or subclinical prior to pregnancy. Women without preexisting DI can also be affected by the actions of placental vasopressinase which increases in activity between the 4th and 38th weeks of gestation, leading to accelerated metabolism of AVP and causing a transient form of DI of pregnancy. This type of DI may be associated with certain complications during pregnancy and delivery, such as preeclampsia. Management of DI of pregnancy depends on the pathophysiology of the disease; forms of DI that lack AVP can be treated with desmopressin (DDAVP), while forms of DI that involve resistance to AVP require evaluation of the underlying causes.

Transient diabetes insipidus in pregnancy

Gestational diabetes insipidus (DI) is a rare complication of pregnancy, usually developing in the third trimester and remitting spontaneously 4–6 weeks post-partum. It is mainly caused by excessive vasopressinase activity, an enzyme expressed by placental trophoblasts which metabolises arginine vasopressin (AVP). Its diagnosis is challenging, and the treatment requires desmopressin. A 38-year-old Chinese woman was referred in the 37th week of her first single-gestation due to polyuria, nocturia and polydipsia. She was known to have gestational diabetes mellitus diagnosed in the second trimester, well-controlled with diet. Her medical history was unremarkable. Physical examination demonstrated decreased skin turgor; her blood pressure was 102/63 mmHg, heart rate 78 beats/min and weight 53 kg (BMI 22.6 kg/m²). Laboratory data revealed low urine osmolality 89 mOsmol/kg (350–1000), serum osmolality 293 mOsmol/kg (278–295), serum sodium 144 mmol/l (135–145), potassium 4.1 mmol/l (3.5–5.0), urea 2.2 mmol/l (2.5–6.7), glucose 3.5 mmol/l and HbA1c 5.3%. Bilirubin, alanine transaminase, alkaline phosphatase and full blood count were normal. The patient was started on desmopressin with improvement in her symptoms, and normalisation of serum and urine osmolality (280 and 310 mOsmol/kg respectively). A fetus was delivered at the 39th week without major problems. After delivery, desmopressin was stopped and she had no further evidence of polyuria, polydipsia or nocturia. Her sodium, serum/urine osmolality at 12-weeks post-partum were normal. A pituitary magnetic resonance imaging (MRI) revealed the neurohypophyseal T1-bright spot situated ectopically, with a normal adenohypophysis and infundibulum. She remains clinically well, currently breastfeeding, and off all medication. This case illustrates some challenges in the diagnosis and management of transient gestational DI.

Subclinical diabetes insipidus

Subclinical central diabetes insipidus (CDI) can be the outcome of a number of diseases that affect the hypothalamus-infundibulum-post hypophysis axis. One of the most common forms of subclinical CDI is linked to an autoimmune pathogenesis even if other causes may be also responsible. Among these, pregnancy, traumatic and surgical brain injury and some infiltrative, vascular, infectious and neoplastic diseases have been reported with increasing frequency. The natural history of autoimmune CDI seems to evolve through 4 functional stages according to the presence of antibodies to vasopressin-secreting cells (AVPcAb) and the relationship between their behavior overtime, the variations of posterior pituitary function and the characteristics of hypothalamic-hypophyseal region on magnetic resonance imaging. This staging is of crucial importance for the therapeutic strategy, taking into account that some stages could be still reversible. Several medical treatments have been suggested to interrupt the progression toward clinical CDI but the results are still discussed.

Recurrent pregnancy-induced diabetes insipidus in a woman with hemochromatosis

Diabetes insipidus is a rare disorder in pregnant women, predating pregnancy or appearing for the first time during gestation. In pregnancy it usually affects women with HELLP syndrome or acute fatty liver of pregnancy and results from the reduced hepatic degradation of placental vasopressinase leading to its increased activity. Although infiltrative diseases have been found to cause diabetes insipidus in non-pregnant population, very few studies showed that these disorders may manifest for the first time during gestation. We describe here the case of transient diabetes insipidus in two subsequent pregnancies of a female with hemochromatosis. The first symptoms of this disease appeared for the first time at the beginning of the third trimester of her second pregnancy, and diagnosis was established on the basis of typical clinical presentation, confirmed by a water deprivation test. Diabetes insipidus resulted from the increased activity of vasopressinase, caused by hemochromatosis-induced liver dysfunction, the presence of which was confirmed between the pregnancies by liver biopsy and identification of the HFE gene mutation. Subsequent desferrioxamine treatment resulted in a less severe clinical course of diabetes insipidus in the last patient's pregnancy. In both pregnancies, the patient was successfully treated with oral desmopressin, which is resistant to degradation by placental vasopressinase. Although unrecognized pituitary disorders may pose a serious health problem to the mother and fetus, hemochromatosis-induced diabetes insipidus, as the case of our patient demonstrates, if effectively diagnosed and treated, cannot be regarded as a contraindication for pregnancy.

Diabetes insipidus in pregnancy: etiology, evaluation, and management

OBJECTIVE

To review the approach to a patient with diabetes insipidus during pregnancy.

METHODS

This review examines the normal physiology of water homeostasis, the related changes that occur during pregnancy, and the pathophysiology of diabetes insipidus in pregnancy. Associated complications, evaluation, and management are discussed.

RESULTS

Diabetes insipidus can complicate up to 1 in 30,000 pregnancies. Diabetes insipidus during pregnancy has a variety of causes, some that predate the pregnancy and others that begin during gestation. Polyuria and polydipsia can occur or be exacerbated in women with overt or subclinical central or nephrogenic diabetes insipidus. These women have either decreased central secretory reserve or impaired renal responsiveness to vasopressin. In addition, women can experience diabetes insipidus de novo in pregnancy through the actions of placental vasopressinase, which causes accelerated degradation of vasopressin. This form of diabetes insipidus may be associated with increased complications of pregnancy, including preeclampsia. Management of central diabetes insipidus and transient diabetes insipidus of pregnancy can be achieved with 1-deamino-8-D-arginine vasopressin (desmopressin acetate) (DDAVP), a vasopressin analogue. Nephrogenic diabetes insipidus is typically resistant to both DDAVP and vasopressin and underlying causes should be addressed.

CONCLUSIONS

Increased awareness of diabetes insipidus in pregnancy may lead to early diagnosis and appropriate treatment that will reduce the risks of maternal and fetal morbidity. Overall, growing experience with DDAVP has shown that it is a safe and effective treatment for diabetes insipidus caused by a variety of factors.