Case report: Adrenal LH/hCG receptor overexpression and gene amplification causing pregnancy-induced Cushing's syndrome

Pregnancy complicated with adrenal adenoma causing ACTH-independent Cushing's syndrome, accompanied by obstetric antiphospholipid syndrome and severe pre-eclampsia: case report and literature review

This case report shares the management experience of a patient with pregnancy combined with adrenal adenoma causing ACTH-independent Cushing's syndrome (CS), accompanied by obstetric antiphospholipid syndrome (OAPS) and severe pre-eclampsia. The case was a 26-year-old that presented with typical clinical symptoms and signs of CS. The patient had a history of 4 spontaneous abortions in the last 4 years. The 24-hour urinary free cortisol was significantly increased, an abnormal cortisol circadian rhythm was demonstrated by a high late-night salivary cortisol, blood ACTH was suppressed (< 1ng/dL), anticardiolipin antibody was positive, and imaging examination showed an adrenal tumor. The patient underwent laparoscopic adrenal tumor resection under general anesthesia at 23 weeks of gestation. The tumor was pathologically confirmed to be an adrenocortical adenoma. The patient underwent a cesarean section at 39 weeks of gestation to give birth to a healthy baby girl with an Apgar score of 10. Pregnancy complicated by CS is clinically rare, easily masked by normal physiological changes of pregnancy, and is difficult to diagnose. The determination of 24-hour urinary free cortisol, the circadian rhythm of serum cortisol, ultrasound, and MRI can be helpful in the diagnosis of CS during pregnancy. Surgery is the first choice for the treatment of CS during pregnancy. As a subtype of antiphospholipid syndrome, patients with OAPS are prone to thrombotic events and recurrent miscarriages if not treated accordingly. To our knowledge no cases of CS with OAPS and severe pre-eclampsia have been reported. We summarize the experience of the treatment of this patient and review the literature to improve clinicians' awareness of this disease.

Clinical, pathophysiologic, genetic and therapeutic progress in Primary Bilateral Macronodular Adrenal Hyperplasia

Patients with primary bilateral macronodular adrenal hyperplasia (PBMAH) usually present bilateral benign adrenocortical macronodules at imaging and variable levels of cortisol excess. PBMAH is a rare cause of primary overt Cushing's syndrome, but may represent up to one third of bilateral adrenal incidentalomas with evidence of cortisol excess. The increased steroidogenesis in PBMAH is often regulated by various G-protein coupled receptors aberrantly expressed in PBMAH tissues; some receptor ligands are ectopically produced in PBMAH tissues creating aberrant autocrine/paracrine regulation of steroidogenesis. The bilateral nature of PBMAH and familial aggregation, led to the identification of germline heterozygous inactivating mutations of the ARMC5 gene, in 20-25% of the apparent sporadic cases and more frequently in familial cases; ARMC5 mutations/pathogenic variants can be associated with meningiomas. More recently, combined germline mutations/pathogenic variants and somatic events inactivating the KDM1A gene were specifically identified in patients affected by GIP-dependent PBMAH. Functional studies demonstrated that inactivation of KDM1A leads to GIP-receptor (GIPR) overexpression and over or down-regulation of other GPCRs. Genetic analysis is now available for early detection of family members of index cases with PBMAH carrying identified germline pathogenic variants. Detailed biochemical, imaging, and co-morbidities assessment of the nature and severity of PBMAH is essential for its management. Treatment is reserved for patients with overt or mild cortisol/aldosterone or other steroid excesses taking in account co-morbidities. It previously relied on bilateral adrenalectomy; however recent studies tend to favor unilateral adrenalectomy, or less frequently, medical treatment with cortisol synthesis inhibitors or specific blockers of aberrant GPCR.

Peptidergic G Protein-Coupled Receptor Regulation of Adrenal Function: Bench to Bedside and Back

An altered secretion of adrenocortical and adrenomedullary hormones plays a role in the clinical syndromes of primary aldosteronism (PA), Cushing, and pheochromocytoma. Moreover, an altered production of adrenocortical hormones and/or an abnormal release of factors by the adrenal medulla are involved in several other diseases, including high blood pressure, congestive heart failure, liver cirrhosis, nephrotic syndrome, primary reninism, renovascular hypertension, Addison disease, Bartter, Gitelman, and virilization syndromes. Understanding the regulation of adrenal function and the interactions between adrenal cortex and medulla is, therefore, the prerequisite for mechanistic understanding of these disorders. Accumulating evidence indicates that the modulation of adrenal hormone biosynthesis is a process far more complex than originally thought, as it involves several factors, each cooperating with the other. Moreover, the tight vascular and neural interconnections between the adrenal cortex and medulla underlie physiologically relevant autocrine/paracrine interactions involving several peptides. Besides playing a pathophysiological role in common adrenal diseases, these complex mechanisms could intervene also in rare diseases, such as pheochromocytoma concomitant with adrenal Cushing or with PA, and PA co-occurring with Cushing, through mechanisms that remain to be fully understood at the molecular levels. Heterodimerization of G protein-coupled receptors (GPCRs) induced by peptide signaling is a further emerging new modulatory mechanism capable of finely tuning adrenal hormones synthesis and release. In this review we will examine current knowledge on the role of peptides that act via GPCRs in the regulation of adrenal hormone secretion with a particular focus on autocrine-paracrine signals.

Pregnancy-induced Cushing's syndrome with an adrenocortical adenoma overexpressing LH/hCG receptors: a case report

BACKGROUND

Pregnancy-induced Cushing's syndrome (CS) with an adrenocortical adenoma overexpressing luteinizing hormone (LH)/human choriogonadotropin (hCG) receptors (LHCGR) has been rarely reported in the literatures. This peculiar condition challenges the canonical diagnosis and management of CS.

CASE PRESENTATION

A 27-year-old woman (G2P0A1) presented at 20 weeks gestational age (GA) with overt Cushingoid clinical features. Adrenocorticotropic hormone (ACTH)-independent CS was diagnosed based on undetectable ACTH and unsuppressed cortisol levels by dexamethasone. Magnetic resonance imaging (MRI) scanning without contrast revealed a left adrenal nodule while pituitary MRI scanning was normal. A conservative treatment strategy of controlling Cushingoid comorbidities was conducted. At 36 weeks GA, a caesarean operation was performed and a live female infant was delivered. At 8 weeks after parturition, our patient achieved normalization of blood pressure, blood glucose, serum potassium, and urinary cortisol level spontaneously. During non-pregnancy period, stimulation testing with exogenous hCG significantly evoked a cortisol increase. The woman underwent resection of the adrenal tumor at 6 months after parturition. Immunohistochemistry (IHC) showed the tumor tissue that stained positive for luteinizing hormone (LH)/human choriogonadotropin (hCG) receptor (LHCGR), whereas negative for both melanocortin 2 receptor (MC2R) and G protein-coupled receptor-1 (GPER-1).

CONCLUSIONS

Stimulation test with exogenous hCG after parturition is necessary for the diagnosis of pregnancy-induced CS. LHCGR plays an essential role in the pathogenesis of this rare condition.

Endocrine causes of hypertension in pregnancy

Hypertension is a common and morbid complication of pregnancy. While endocrine causes of secondary hypertension are not rare, women with these conditions do not often conceive, and even less commonly are these disorders diagnosed during pregnancy. This review will consider conditions of adrenal hormone excess that cause secondary hypertension: primary aldosteronism (PA), Cushing syndrome (CS), and pheochromocytoma/paraganglioma. We emphasize that pregnancy itself elicits changes in the regulation of aldosterone and cortisol production and standard endocrine testing algorithms. Furthermore, conventional imaging modalities and pharmacotherapies are often contraindicated in pregnancy, which complicates diagnosis and management. Nevertheless, surgical management in the second trimester is the preferred treatment strategy for most of these rare cases when feasible. This article will discuss the approach to patients with endocrine causes of hypertension during pregnancy with emphasis on those aspects that deviate from the assessment and treatment of non-pregnant patients.

Approach to Cushing's syndrome in pregnancy: two cases of Cushing's syndrome in pregnancy and a review of the literature

Cushing's syndrome (CS) rarely occurs during pregnancy. The primary aim of this article is to propose a therapeutic approach to CS in pregnancy. Here, we present two cases of CS in pregnancy and a literature review. This article proposes the early diagnostic points, especially the clinical approach to this medical condition, mainly for pregnant women without a previous diagnosis of CS. More importantly, we present therapeutic strategies for CS during pregnancy, especially glucocorticoid replacement for perioperative, postoperative, and perinatal periods in pregnant women with CS in order to minimize complications for both mother and fetus. At the same time, we also assess the anxiety status of patients. This article summarizes the approach to CS in pregnancy, not only with a physiological assessment but with a psychological assessment as well.

The adrenal cortex: Physiology and diseases in human pregnancy

Pregnancy is characterized by marked alterations in the hypothalamic-pituitary-adrenal axis and in the function of the adrenal gland. Some of those alterations have clinical characteristics that are similar to those of adrenal gland disorders. While adrenal disorders are rare among pregnant women, they harbor the potential for significant morbidity if they remain unrecognized and untreated. As the majority of patients with adrenal disorders present with clinical features that are typical of normal pregnancy - diagnosis during pregnancy is not uncommonly delayed. A high index of suspicion must be practiced for these disorders as they might carry severe obstetrical negative outcomes. In this review we will survey the normal function of adrenal glands in pregnancy and the role of adrenal hormones in pregnancy. We will outline the adrenal disorders that commonly present during pregnancy and review the literature on treatment modalities.

Exacerbation of Cushing's syndrome during pregnancy: stimulation of a cortisol-secreting adrenocortical adenoma by ACTH originating from the foeto-placental unit

A 29-year-old G4A3 woman presented at 25 weeks of pregnancy with progressive signs of Cushing's syndrome (CS), gestational diabetes requiring insulin and hypertension. A 3.4 × 3.3 cm right adrenal adenoma was identified during abdominal ultrasound imaging for nephrolithiasis. Investigation revealed elevated levels of plasma cortisol, 24 h urinary free cortisol (UFC) and late-night salivary cortisol (LNSC). Serum ACTH levels were not fully suppressed (4 and 5 pmol/L (N: 2-11)). One month post-partum, CS regressed, 24-h UFC had normalised while ACTH levels were now less than 2 pmol/L; however, dexamethasone failed to suppress cortisol levels. Tests performed in vivo 6 weeks post-partum to identify aberrant hormone receptors showed no cortisol stimulation by various tests (including 300 IU hLH i.v.) except after administration of 250 µg i.v. Cosyntropin 1-24. Right adrenalectomy demonstrated an adrenocortical adenoma and atrophy of adjacent cortex. Quantitative RT-PCR analysis of the adenoma revealed the presence of ACTH (MC2) receptor mRNA, while LHCG receptor mRNA was almost undetectable. This case reveals that CS exacerbation in the context of pregnancy can result from the placental-derived ACTH stimulation of MC2 receptors on the adrenocortical adenoma. Possible contribution of other placental-derived factors such as oestrogens, CRH or CRH-like peptides cannot be ruled out. Learning points: Diagnosis of Cushing's syndrome during pregnancy is complicated by several physiological alterations in hypothalamic-pituitary-adrenal axis regulation occurring in normal pregnancy. Cushing's syndrome (CS) exacerbation during pregnancy can be associated with aberrant expression of LHCG receptor on primary adrenocortical tumour or hyperplasia in some cases, but not in this patient. Placental-derived ACTH, which is not subject to glucocorticoid negative feedback, stimulated cortisol secretion from this adrenal adenoma causing transient CS exacerbation during pregnancy. Following delivery and tumour removal, suppression of HPA axis can require several months to recover and requires glucocorticoid replacement therapy.

Genetics of micronodular adrenal hyperplasia and Carney complex

Micronodular bilateral adrenal hyperplasia (MiBAH) is a rare cause of adrenal Cushing syndrome (CS). The investigations carried out on this disorder during the last two decades suggested that it could be divided into at least two entities: primary pigmented nodular adrenocortical disease (PPNAD) and isolated micronodular adrenocortical disease (i-MAD). The most common presentation of MiBAH is familial PPNAD as part of Carney complex (CNC) (cPPNAD). CNC, associated with multiple endocrine and non-endocrine neoplasias, was first described in 1985 in 40 patients, 10 of whom were familial cases. In 2000, we identified inactivating germline mutations of the PRKAR1A gene, encoding the regulatory subunit type 1α (RIα) of protein kinase A (PKA), in the majority of patients with CNC and PPNAD. PRKAR1A mutations causing CNC lead to increased PKA activity. Since then, additional genetic alterations in the cAMP/PKA signaling pathway leading to increased PKA activity have been described in association with MiBAH. This review summarizes older and recent findings on the genetics and pathophysiology of MiBAH, PPNAD, and related disorders.

Aberrant G-protein coupled hormone receptor in adrenal diseases

The regulation of cortisol or aldosterone production when ACTH of pituitary origin or the renin-angiotensin systems are suppressed in primary adrenal Cushing's syndrome or in primary aldosteronism is exerted by diverse genetic and molecular mechanisms. In addition to recently identified mutations in various genes implicated in the cyclic AMP or ion channel pathways, steroidogenesis is not really autonomous as it is frequently regulated by the aberrant adrenocortical expression of diverse hormone receptors, particularly G-protein coupled hormone receptors (GPCR) which can substitute for the normal function of ACTH or angiotensin-II. In addition, paracrine or autocrine production of ligands for the aberrant GPCR such as ACTH or serotonin is found in some adrenal tumors or hyperplasias and participates in a complex regulatory loop causing steroid excess. Targeted therapies to block the aberrant ligands or their receptors could become useful in the future, particularly for patients with bilateral source of steroid excess.

Adrenal Cushing's syndrome during pregnancy

Cushing syndrome (CS) during pregnancy is a rare condition with only a few cases reported in the literature. Misdiagnosis of CS is common because of overlapping features like fatigue, weight gain, striae and emotional changes that can occur during normal pregnancy. Changes in maternal hormones and their binding proteins complicate assessment of glucocorticoid hormone levels during gestation. CS during pregnancy is most frequently due to an adrenal adenoma and to a lesser degree to adrenocorticotropic hormone (ACTH) hypersecretion by a pituitary adenoma. Furthermore, aberrant expression of luteinizing hormone (LH) receptors in the adrenal cortex has been suggested to be involved in the pathogenesis of adrenal CS during pregnancy. We report three pregnant women with ACTH-independent Cushing's syndrome and an adrenal tumor. After uncomplicated delivery, patient 1 underwent in vivo testing for aberrant hormone receptor expression by the adenoma. Cortisol responses were found after administration of luteinizing hormone-releasing hormone (LHRH), human chorionic gonadotropin (hCG), glucagon, vasopressin and a standard mixed meal. All patients were treated with laparoscopic adrenalectomy. Adrenal tumor tissue of two patients showed positive immunohistochemical staining of LH receptors. Considering the cortisol responses to LHRH and hCG, and the development of CS during pregnancy in these patients, it is likely that ACTH-independent hypercortisolism was induced by the pregnancy-associated rise in hCG levels that activated aberrantly expressed LH receptors in the adrenal adenoma. Remarkably, adrenal adenomas may simultaneously express multiple aberrant receptors and individual ligands may play a role in the regulation of cortisol production in CS during pregnancy.

Cushing's syndrome and pregnancy outcomes: a systematic review of published cases

Pregnancy in Cushing's syndrome (CS) is extremely rare due to the influence of hypercortisolism on the reproductive axis. Purpose of this study is to investigate whether the etiology of CS in pregnancy determines a different impact on the fetal/newborn and maternal outcomes. We performed a systematic review of cases published in the literature from January 1952 to April 2015 including the words "Cushing AND pregnancy". We included 168 manuscripts containing 220 patients and 263 pregnancies with active CS during pregnancy and with a history of CS but treated and cured hypercortisolism at the time of gestation. Adrenal adenoma was the main cause of active CS during pregnancy (44.1 %). Women with active CS had more gestational diabetes mellitus (36.9 vs. 2.3 %, p = 0.003), gestational hypertension (40.5 vs. 2.3 %, p < 0.001) and preeclampsia (26.3 vs. 2.3 %, p = 0.001) than those with cured disease. The proportion of fetal loss in active CS was higher than in cured CS (23.6 vs. 8.5 %, p = 0.021), as well as global fetal morbidity (33.3 vs. 4.9 %, p < 0.001). The predictors of fetal loss in active CS were etiology of hypercortisolism [Odds Ratio -OR-for pregnancy-induced CS 4.7 (95 % Confidence Interval-CI 1.16-18.96), p = 0.03], publication period [OR for "1975-1994" 0.10 (95 % CI 0.03-0.40), p = 0.001] and treatment during gestation (p = 0.037, [OR medical treatment 0.25 (95 % CI 0.06-1.02), p = 0.052], [OR surgical treatment 0.34 (95 % CI 0.11-1.06), p = 0.063]). The period of diagnosis of CS (before, during or after pregnancy) was the only predictor of overall fetal morbimortality [OR for diagnosis during pregnancy 4.66 (95 % CI 1.37-15.83), p = 0.014]. Patients with active CS, especially in pregnancy-induced CS, experienced more problems in pregnancy and had the worst fetal prognosis in comparison to other causes. Diagnosis of CS during pregnancy was also associated with worse overall fetal morbimortality. Both medical treatment and surgery during pregnancy appeared to be protective in avoiding fetal loss.

Functional Implications of LH/hCG Receptors in Pregnancy-Induced Cushing Syndrome

Context:

Elevated human choriogonadotropin (hCG) may stimulate aberrantly expressed luteinizing hormone (LH)/hCG receptor (LHCGR) in adrenal glands, resulting in pregnancy-induced bilateral macronodular adrenal hyperplasia and transient Cushing syndrome (CS).

Objective:

To determine the role of LHCGR in transient, pregnancy-induced CS.

Design, Setting, Patient, and Intervention:

We investigated the functional implications of LHCGRs in a patient presenting, at a tertiary referral center, with repeated pregnancy-induced CS with bilateral adrenal hyperplasia, resolving after parturition.

Main Outcome Measures and Results:

Acute testing for aberrant hormone receptors was negative except for arginine vasopressin (AVP)–increased cortisol secretion. Long-term hCG stimulation induced hypercortisolism, which was unsuppressed by dexamethasone. Postadrenalectomy histopathology demonstrated steroidogenically active adrenocortical hyperplasia and ectopic cortical cell clusters in the medulla. Quantitative polymerase chain reaction showed upregulated expression of LHCGR, transcription factors GATA4, ZFPM2, and proopiomelanocortin (POMC), AVP receptors (AVPRs) AVPR1A and AVPR2, and downregulated melanocortin 2 receptor (MC2R) vs control adrenals. LHCGR was localized in subcapsular, zona glomerulosa, and hyperplastic cells. Single adrenocorticotropic hormone–positive medullary cells were demonstrated in the zona reticularis. The role of adrenal adrenocorticotropic hormone was considered negligible due to downregulated MC2R. Coexpression of CYP11B1/CYP11B2 and AVPR1A/AVPR2 was observed in ectopic cortical cells in the medulla. hCG stimulation of the patient’s adrenal cell cultures significantly increased cyclic adenosine monophosphate, corticosterone, 11-deoxycortisol, cortisol, and androstenedione production. CTNNB1, PRKAR1A, ARMC5, and PRKACA gene mutational analyses were negative.

Conclusion:

Nongenetic, transient, somatic mutation-independent, pregnancy-induced CS was due to hCG-stimulated transformation of LHCGR-positive undifferentiated subcapsular cells (presumably adrenocortical progenitors) into LHCGR-positive hyperplastic cortical cells. These cells respond to hCG stimulation with cortisol secretion. Without the ligand, they persist with aberrant LHCGR expression and the ability to respond to the same stimulus.

Adrenal cortex expression quantitative trait loci in a German Holstein × Charolais cross

Background

The importance of the adrenal gland in regard to lactation and reproduction in cattle has been recognized early. Caused by interest in animal welfare and the impact of stress on economically important traits in farm animals the adrenal gland and its function within the stress response is of increasing interest. However, the molecular mechanisms and pathways involved in stress-related effects on economically important traits in farm animals are not fully understood. Gene expression is an important mechanism underlying complex traits, and genetic variants affecting the transcript abundance are thought to influence the manifestation of an expressed phenotype. We therefore investigated the genetic background of adrenocortical gene expression by applying an adaptive linear rank test to identify genome-wide expression quantitative trait loci (eQTL) for adrenal cortex transcripts in cattle.

Results

A total of 10,986 adrenal cortex transcripts and 37,204 single nucleotide polymorphisms (SNPs) were analysed in 145 F2 cows of a Charolais × German Holstein cross. We identified 505 SNPs that were associated with the abundance of 129 transcripts, comprising 482 cis effects and 17 trans effects. These SNPs were located on all chromosomes but X, 16, 24 and 28. Associated genes are mainly involved in molecular and cellular functions comprising free radical scavenging, cellular compromise, cell morphology and lipid metabolism, including genes such as CYP27A1 and LHCGR that have been shown to affect economically important traits in cattle.

Conclusions

In this study we showed that adrenocortical eQTL affect the expression of genes known to contribute to the phenotypic manifestation in cattle. Furthermore, some of the identified genes and related molecular pathways were previously shown to contribute to the phenotypic variation of behaviour, temperament and growth at the onset of puberty in the same population investigated here. We conclude that eQTL analysis appears to be a useful approach providing insight into the molecular and genetic background of complex traits in cattle and will help to understand molecular networks involved.

Electronic supplementary material

The online version of this article (doi:10.1186/s12863-016-0442-x) contains supplementary material, which is available to authorized users.

Multiple aberrant hormone receptors in Cushing's syndrome

The mechanisms regulating cortisol production when ACTH of pituitary origin is suppressed in primary adrenal causes of Cushing's syndrome (CS) include diverse genetic and molecular mechanisms. These can lead either to constitutive activation of the cAMP system and steroidogenesis or to its regulation exerted by the aberrant adrenal expression of several hormone receptors, particularly G-protein coupled hormone receptors (GPCR) and their ligands. Screening for aberrant expression of GPCR in bilateral macronodular adrenal hyperplasia (BMAH) and unilateral adrenal tumors of patients with overt or subclinical CS demonstrates the frequent co-expression of several receptors. Aberrant hormone receptors can also exert their activity by regulating the paracrine secretion of ACTH or other ligands for those receptors in BMAH or unilateral tumors. The aberrant expression of hormone receptors is not limited to adrenal CS but can be implicated in other endocrine tumors including primary aldosteronism and Cushing's disease. Targeted therapies to block the aberrant receptors or their ligands could become useful in the future.

Management of adrenal tumors in pregnancy

Adrenal diseases, including Cushing syndrome (CS), primary aldosteronism (PA), pheochromocytoma, and adrenocortical carcinoma, are uncommon in pregnancy; a high degree of clinical suspicion must exist. Physiologic changes to the hypothalamus-pituitary-adrenal axis in a normal pregnancy result in increased cortisol, renin, and aldosterone levels, making the diagnosis of CS and PA in pregnancy challenging. However, catecholamines are not altered in pregnancy and allow a laboratory diagnosis of pheochromocytoma that is similar to that of the nonpregnant state. Although adrenal tumors in pregnancy result in significant maternal and fetal morbidity, and sometimes mortality, early diagnosis and appropriate treatment often improve outcomes.

Cushing's syndrome in pregnancy

Cushing's syndrome is a rare condition in the general population and is even less common during pregnancy with only a few cases reported in literature. The diagnosis of Cushing's syndrome may be difficult during pregnancy because the typical features of the disorder and pregnancy may overlap. However, Cushing's syndrome results in increased fetal and maternal complications, and diagnosis and treatment are critical. This report describes a case of 26-year-old female at the 19th week of pregnancy with symptoms and signs of hypercortisolism, where ACTH-independent Cushing's syndrome was diagnosed and treated by robotic laparoscopic adrenalectomy at the 21th week of gestation.

Adrenal diseases during pregnancy: pathophysiology, diagnosis and management strategies

: Adrenal diseases--including disorders such as Cushing's syndrome, Addison's disease, pheochromocytoma, primary hyperaldosteronism and congenital adrenal hyperplasia--are relatively rare in pregnancy, but a timely diagnosis and proper treatment are critical because these disorders can cause maternal and fetal morbidity and mortality. Making the diagnosis of adrenal disorders in pregnancy is challenging as symptoms associated with pregnancy are also seen in adrenal diseases. In addition, pregnancy is marked by several endocrine changes, including activation of the renin-angiotensin-aldosterone system and the hypothalamic-pituitary-adrenal axis. The aim of this article was to review the pathophysiology, clinical manifestation, diagnosis and management of various adrenal disorders during pregnancy.

Recurrent ACTH-independent Cushing's syndrome in multiple pregnancies

A 27-year-old woman presented with Cushing's syndrome. Typical clinical symptoms and signs developed at the beginning of each pregnancy. The latest three pregnancies all ended with natural abortion at about three months. It was the fourth time that she was pregnant. By week 18 of gestation, plasma cortisol diurnal rhythm was absent, basal urinary free cortisol was 1650 μg/24 h and ACTH levels were suppressed. The diagnosis of ACTH-independent Cushing's syndrome was established. Cushing's syndrome in the patient resolved within four weeks of abortion. But signs and symptoms of hypercortisolism recurred in the fifth pregnancy and resolved soon after abortion during the follow-up. The mechanisms by which pregnancy-induced Cushing's syndrome occurred in this patient are unclear. Aberrant responsiveness or hyperresponsiveness of adrenocortical cells to a non-ACTH and non-CRH substance produced in excess in pregnancy should be considered.

Adrenal disorders in pregnancy

Pregnancy is marked by alterations in a number of endocrine systems, including activation of the renin-angiotensin-aldosterone system and the hypothalamic-pituitary-adrenal axis. The placenta, the fetal adrenal glands and the liver constitute an interactive endocrine entity, known as the fetoplacental unit. In the fetoplacental unit, the fetal adrenal glands are the primary source of dehydroepiandrosterone sulphate, which is further metabolized by the fetal liver and placenta to produce a variety of oestrogens. Several disorders can affect both the fetal and maternal adrenal glands during pregnancy. The most common fetal adrenal disorder, steroid 21-hydroxylase deficiency, leads to abnormalities in sexual development and can be life threatening for the neonate. Although rare, maternal adrenal disorders are associated with considerable maternal mortality and morbidity if not promptly recognized and treated. However, diagnosis is often difficult to establish because of the endocrine changes occurring during normal pregnancies and the lack of reference values for the majority of the adrenal steroids. This Review provides an overview of adrenal steroid metabolism during pregnancy and focuses on diagnosis and treatment of the most common fetal and maternal adrenal disorders.

Adrenal disease in pregnancy

Adrenal disorders in pregnancy are relatively rare, yet can lead to significant maternal and fetal morbidity. Making a diagnosis is challenging as pregnancy may alter the manifestation of disease, many signs and symptoms associated with pregnancy are also seen in adrenal disease, and the fetal-placental unit alters the maternal endocrine metabolism and hormonal feedback mechanisms. The most common cause of Cushing's syndrome in pregnancy is an adrenal adenoma, followed by pituitary etiology, adrenal carcinoma, and other exceedingly rare causes. Medical therapy of Cushing's syndrome includes metyrapone and ketoconazole, but generally surgical treatment is more effective. Exogenous corticosteroid administration is the most common cause of adrenal insufficiency, followed by the endogenous causes of ACTH or CRH secretion. Primary adrenal insufficiency is least common. A low early morning cortisol <3 mcg/dL (83 mmol/L) in the non-stressed state and in the setting of typical clinical symptoms confirms the diagnosis. In the second and third trimester cortisol rises to levels 2-3 fold above those in the non-pregnant state, therefore a baseline level of <30 mcg/dL (823 mmol/L) warrants further evaluation. ACTH stimulated normal cortisol values have been established for each trimester. Hydrocortisone, which does not cross the placenta, is the glucocorticoid treatment of choice, and fludrocortisone is used as mineralocorticoid replacement in patients with primary disease. Congenital adrenal hyperplasia is an autosomal recessive disorder; 21-hydroxylase deficiency (21OHD) is the most common form of the disease. Non-classical 21OHD is most common, followed by the salt-wasting and simple virilizing forms. The treatment of choice for pregnant women affected with CAH is hydrocortisone, and fludrocortisones is added for those with the salt-wasting form of the disease. If the fetus is at risk for classical CAH, dexamethasone treatment can be used prenatally to prevent masculinization of the genitalia in a female infant. Because dexamethasone crosses the placenta, it should not be used to treat pregnant women with CAH if the fetus is not at risk for the disease.

Management of pituitary tumors in pregnancy

Pituitary tumors, usually adenomas, account for about 10-15% of all intracranial tumors. Their treatment, which includes surgery, medicine or radiotherapy, either isolated or in combination, aims to halt tumor growth or achieve tumor shrinkage, as well as control hormone hypersecretion or ensure hormone replacement. Such approaches have made pregnancy possible for women with pituitary adenomas. Medical therapy with dopamine agonists is the treatment of choice for most patients with prolactinomas, with surgery reserved for individuals resistant to drugs. On the other hand, surgery before conception is indicated as a first-line approach in patients with acromegaly, Cushing disease or clinically nonfunctioning pituitary macroadenomas. In these patient populations, medical therapy with somatostatin analogues (acromegaly) or drugs that target the adrenal glands, such as metyrapone and ketoconazole (Cushing disease), should be reserved for those in whom surgery is unsuccessful or contraindicated.

Human adrenal LH/hCG receptors and what they could mean for adrenal physiology and pathology

Although the research on the potential regulation of human adrenal cortex by LH and hCG is still in its infancy, the available evidence supports the presence of very low levels of LH/hCG receptors in entire zona reticularis and deeper part of zona fasciculata. The activation of these receptors may lead to an increased secretion of androgens and/or cortisol. The same chronically elevated levels, along with unknown genetic and epigenetic changes, may also lead to the formation of tumors that can secrete all three major classes of adrenal steroid hormones. As shown in murine models, the increased receptor levels often seen in tumors, are probably caused by elevated LH/hCG levels. However, the elevated LH/hCG levels or their receptors alone may not be sufficient for the development of adrenal pathology. Therefore, further studies to advance our current understanding on the pathophysiology of human adrenal hCG/LH receptors are required.