Hyperparathyroidism in pregnancy: diagnostic dilemma?

Hyperparathyroidism in Pregnancy: A Review of the Literature

Importance

Maternal hyperparathyroidism can be associated with significant maternal and fetal morbidity and fetal mortality. Because the maternal symptoms are typically nonspecific, the disorder may not be recognized leading to adverse pregnancy outcomes.

Objective

The aim of this study was to review the literature on the etiology/prevalence, pathophysiology, diagnosis, management (medical and surgical), and the maternal/neonatal complications associated with pregnancies complicated by hyperparathyroidism.

Evidence Acquisition

A literature search was undertaken by our university librarian using the search engines PubMed and Web of Science. Search terms used included "hyperparathyroidism" AND "pregnancy" OR "pregnancy complications" OR "maternal." The number of years searched was not limited, but the abstracts had to be in English.

Results

There were 309 abstracts identified, 164 of which are the basis of this review. This includes 137 articles of the 269 individual case reports in the literature since the first case report in 1947. The articles and case reports reviewed the etiology, risk factors, diagnosis, management, complications, and maternal/fetal outcomes of pregnancies complicated by hyperparathyroidism.

Conclusions and Relevance

Undiagnosed maternal hyperparathyroidism can result in critical maternal and fetal outcomes during pregnancy. This review highlights what is currently known about hyperparathyroidism during pregnancy to increase the awareness of this serious pregnancy disorder.

A neonate with late-onset hypocalcemia due to unrecognized maternal hyperparathyroidism and a systematic overview of similar cases

Objective: Neonatal seizures are alarming manifestations of an underlying significant disorder demanding immediate attention and intervention. Hypocalcemia, although rare, must be considered in the differential diagnosis of neonatal seizures. Method: We present an unusual case of a 10-day-old infant with unexplained symptomatic hypocalcemia, experiencing multiple episodes of focal tonic-clonic seizures, born by an entirely asymptomatic mother. Moreover, we conducted a systematic search in PubMed and Scopus databases to present a clinical overview of all similar cases. Result: Maternal laboratory investigation revealed markedly increased calcium levels with concomitant high parathyroid hormone levels due to a parathyroid adenoma, undiagnosed during antenatal checkup. Conclusion: This is one of the few cases in the literature where neonatal symptomatology led to the diagnosis of undiagnosed maternal hyperparathyroidism. Early detection and appropriate management of neonatal hypocalcemia could eliminate serious maternal and fetal morbidity.

Recurrent pancreatitis induced by hyperparathyroidism in pregnancy

Introduction

As primary hyperparathyroidism affects mainly middle-aged and elderly women, it is an infrequent finding during gestation and breastfeeding. To date, less than 200 pregnant patients with primary hyperparathyroidism diagnosed during pregnancy have been described. Like in other disorders of the parathyroid gland, the recognition of primary hyperparathyroidism during pregnancy and lactation may be difficult, as clinical symptoms are not specific, while laboratory findings may be masked by some typical pregnancy-induced changes in calcium and phosphate homeostasis. If remains untreated, the disease may result in serious clinical implications for the mother and fetus. Most authors consider surgery within the second trimester of pregnancy as the treatment of choice in this group of patients.

Case report

In our paper, we discuss the case of a 35-year-old female with a history of recurrent acute pancreatitis and recurrent abortions. As the patient declined surgery, conservative management with calcitonin was started and continued throughout the rest of pregnancy, and led to giving birth to the infant whose only health problem was transient hypocalcemia.

Conclusion

The described case shows that conservative management, if started respectively early and conducted on the basis of a patient’s condition, may effectively reduce increased perinatal and maternal morbidity and mortality in pregnant women declining surgery.

Three case reports of maternal primary hyperparathyroidism in each trimester and a review of optimal management in pregnancy

Primary hyperparathyroidism (PHPT) during pregnancy is associated with significant maternal and fetal risks. Prompt diagnosis and effective management during pregnancy can improve both maternal and fetal outcomes. However, there is no consensus with regard to conservative versus surgical management especially in the first and third trimester. We report three cases of PHPT associated with pregnancy that underwent parathyroidectomy each in a different trimester. Cases 1 and 2 were found to have hypercalcaemia and elevated parathyroid hormone levels in the second and first trimesters, respectively. Case 3 was known to have PHPT prenatally but previously declined parathyroidectomy. All three cases underwent parathyroidectomies during pregnancy without significant postoperative complications and all achieved favourable maternal and neonatal outcomes. Maternal hyperparathyroidism represents a preventable cause of maternal morbidity, with fetal morbidity and mortality. The benefits of parathyroidectomy with normalization of serum calcium in the mothers outweigh the risks of hypercalcaemia and suppression of the fetal parathyroid, especially where maternal vitamin D concentration is low.

Hypocalcemic tetany in the newborn as a manifestation of unrecognized maternal primary hyperparathyroidism

Primary hyperparathyroidism (PHP) during pregnancy is a very rare event that increases maternal and perinatal morbidity and mortality. We present a case in which hypocalcemic tetany of the neonatal infant - caused by transient hypoparathyroidism in the child - finally revealed asymptomatic maternal PHP. An apparently healthy 30-year-old woman had an uneventful pregnancy and delivery. On the 15th postpartal day, the newborn developed hypocalcemic tetany. After receiving supplementation of calcium and vitamin D, the child developed without further pathological findings. Laboratory and radiological studies in the mother led to a diagnosis of maternal PHP. An adenoma of the right lower parathyroid gland was subsequently removed. The search for the cause of hypocalcemia in a newborn should not focus on the patient alone. Examining the apparently healthy mother and approaching the case in a multidisciplinary fashion may benefit both the child and the mother.

Thyroid disease and other endocrine disorders in pregnancy

Endocrine disorders, in particular, thyroid disorders, are common in pregnancy. The endocrine adaptation to pregnancy, need for adequate iodine supplementation, and thyroxine replacement are presented. In addition, autoimmune diseases of the thyroid and pituitary that may occur subsequent to the immune changes of pregnancy and the postpartum period are discussed. A brief account of the presentation of other endocrine disorders (ie, pituitary,parathyroid, calcium, adrenal and gonadal disorders) also is given, along with their evaluation and management.

[Severe primary hyperparathyroidism and vitamin D deficiency]

Primary hyperparathyrodism is a common disease, often asymptomatic. A young post-partum woman was hospitalized for functional impotence of the upper right limb and poor health status. Laboratory tests revealed severe primary hyperparathyroidism (osteitis fibrosa cystica and nephrolithiasis) associated with vitamin D deficiency. Technetium 99m and thallium parathyroid scintigraphy showed increased uptake under the left thyroid lobe. After surgical resection of a parathyroid adenoma, serum calcium fell markedly and parathyroid levels declined but remained above normal. Calcium and 25(OH)-vitamin D supplementation led to normal calcium and vitamin D levels in three Months, with marked improvement in the bone lesions visualized on the six-Month x-rays. Based on this observation, we describe the many radiological aspects of bone involvement in long-standing hyperparathyroidism aggravated by vitamin D deficiency. Early diagnosis of hyperparathyroidism is crucial.

Primary hyperparathyroidism in pregnancy: evidence-based management

Primary hyperparathyroidism during pregnancy poses significant risks to the mother and the fetus. Fortunately, prompt diagnosis and effective management can improve outcomes for both. There is controversy regarding appropriate management of these patients, especially late in gestation. The objective of this article, therefore, is to review the literature and to propose an evidence-based approach to managing these patients. The prevalence of primary hyperparathyroidism in the general population is 0.15%. This condition is more common in women and 25% of cases appear in women during the childbearing years. The true incidence during pregnancy, however, is not known. Because up to 80% of gravid patients with primary hyperparathyroidism are asymptomatic, diagnosing this condition is more difficult. Complications associated with primary hyperparathyroidism in pregnancy have been reported to occur in up to 67% of mothers and 80% of fetuses. In addition to many constitutional symptoms, maternal complications include nephrolithiasis, bone disease, pancreatitis, hyperemesis, muscle weakness, mental status changes, and hypercalcemic crisis. Reported fetal complications include intrauterine growth retardation, low birth weight, preterm delivery, intrauterine fetal demise, postpartum neonatal tetany, and permanent hypoparathyroidism. A four-fold decrease in perinatal complications may be achieved with appropriate therapy. Conservative intervention may be appropriate under certain circumstances, but excision of a parathyroid adenoma remains the only definitive treatment. Debate continues regarding the safety of surgery in the third trimester. However, several cases of successful surgery have been reported.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader will be able to describe the typical presentation of a patient with hyperparathyroidism, summarize the work up and management of a patient with hyperparathyroidism, and list the treatment options for a pregnant patient with hyperparathyroidism.

Primary hyperparathyroidism in a twin pregnancy and review of fetal/maternal calcium homeostasis

BACKGROUND

Hyperparathyroidism occurs rarely in pregnancy; this is the first reported case in a twin gestation. Management of this unusual case is described and an overview of fetal/maternal calcium homeostasis is discussed.

METHODS

The patient presented at 33 weeks' gestation with hypertension and premature labor. Serum calcium and phosphorus were 14.6 and 1.7 mg/dL, respectively. An intact parathyroid hormone (PTH) level was 243 pg/mL (normal, 10-65).

RESULTS

The patient was treated with parenteral saline hydration and oral phosphate supplementation that was continued through week 37. Although the calcium remained elevated between 12.6 and 13.3 mg/dL, medical therapy was continued because of the risks of surgery in the third trimester. Alternative medical treatments (bisphosphonates, calcitonin) were considered ill advised in pregnancy. The patient remained asymptomatic without further labor, and at week 37, fraternal twins were delivered by cesarean section. The infants were monitored closely and experienced no hypocalcemic symptoms after delivery. Postpartum, the mother's parathyroid scan and ultrasound were negative. She underwent neck exploration and a single 700-mg adenoma was removed. Transient asymptomatic hypocalcemia (7.5 mg/dL) occurred postoperatively, and she was placed on oral calcium (1500 mg/day) and calcitriol (0.25 mg/day). These were stopped at 8 weeks, when both PTH and parathyroid hormone-related peptide levels were normal.

CONCLUSION

Mother and infants continue to do well after 18 months. This case provides an interesting setting to consider the interrelationships between elevated maternal PTH and the fetal/placental factors that regulate calcium metabolism in pregnancy.