Factitious Cushing's syndrome

A woman with pituitary-dependent Cushing's disease remained hypercortisolemic after bilateral adrenalectomy. A search for an adrenal remnant by venous catheterization study suggested persistent cortisol-secreting tissue in the left adrenal bed. During ACTH stimulation, plasma corticosterone concentrations remained low and cortisol remained high, suggesting the cortisol was of exogenous origin. Cushingoid features resolved after confronting the patient with this evidence. Plasma corticosterone concentrations played a novel role in the diagnosis of factitiously induced Cushing's syndrome in this patient.     

Factitious,or iatrogenic but unexpected Cushing's syndrome

Prolonged exposition to supraphysiological doses of exogenous glucocorticoid eventually results in iatrogenic Cushing's syndrome, whose intensity depends on the dose and duration of the treatment and on individual susceptibility. In patients with chronic inflammatory diseases treated with oral glucocorticoids iatrogenic Cushing's is expected and recognized and it only imposes that the dose of glucocorticoid be maintained as low as possible and that there is no better alternative therapy available.In some cases, however, iatrogenic Cushing's syndrome may be unexpected by the prescribing physician as the true exposure to corticoids may depend largely on the patient: this is the case for topical steroids used in inflammatory skin diseases such as psoriasis. Factitious Cushing's syndrome (FCS) is another cause of exogenous Cushing's syndrome in whom the exposure to glucocorticoid is unexpected, as it is hidden to the physician by a patient suffering from Münchausen syndrome. FCS might be very difficult to diagnose depending on the type of glucocorticoid used, the specificity of the dosage used for cortisol, and the timing of the measurement of cortisol and ACTH. The best evidence for FCS is the demonstration by LC-MS/MS of exogenous glucocorticoid in his urine or plasma but this requires that the patient has not stopped to take glucocorticoid at the time of exploration. FCS related to hydrocortisone can be difficult to prove and to distinguish from cyclical Cushing's syndrome. Analysis of the literature shows that FCS has led to prolonged or invasive explorations and even to adrenal surgery, while unrecognized FCS has led to fatal infectious complications.     

Cushing's syndrome

During the past 30 years, there have been advances in understanding of the pathogenesis of Cushing's syndrome and in differential diagnosis of its various forms. Improved diagnostic tests and procedures have increased the ability to recognise even mild hypercortisolism and have provided the means to obtain an accurate diagnosis. Despite these advances, the occurrence of unusual clinical presentations and laboratory shortcomings may produce diagnostic problems and challenge clinical intuition. This article reviews recent pathogenic views, new tests, and new diagnostic problems in the evaluation of Cushing's syndrome. Atypical clinical presentations of hypercortisolism and some laboratory shortcomings that may confuse the diagnosis of Cushing's syndrome are also reported.     

Cushing's syndrome

Cushing's syndrome remains one of the most challenging problems in clinical endocrinology. Cushing's disease is caused in the majority of cases by basophil pituitary microadenomas which may be successfully treated by trans-sphenoidal hypophysectomy. Treatment with metyrapone or o,p'-DDD can always induce a clinical remission but not a cure, and neurotransmitter therapy may be effective in a minority of cases. Pituitary irradiation cures about half of cases in the long-term and may be used for surgical failures. Tumours producing ectopic ACTH are frequently benign, small and occult and may produce a syndrome clinically indistinguishable from Cushing's disease. Biochemical investigations cannot absolutely distinguish pituitary from ectopic sources of ACTH and therefore body CT scanning and percatheter venous sampling are essential diagnostic investigations. Tumour localization may result in resection and complete cure, although even small tumours may have a malignant potential. Adrenal tumours are readily diagnosed by plasma ACTH measurement and adrenal CT scanning. Adrenal adenomas are cured by adrenalectomy. Carcinomas may be treated by a combination of adrenalectomy, radiotherapy and o,p'-DDD, but long-term prognosis is poor.     

Cushing's syndrome

The clinical characteristics and current concepts of pathophysiology of Cushing's syndrome have been reviewed. The specific type of pituitary or ectopic ACTH-dependent and ACTH-independent Cushing's syndrome and the underlying pathology can be determined biochemically and with the aid of anatomic localization procedures. Several approaches are available for treating pituitary ACTH-dependent Cushing's syndrome, but transsphenoidal pituitary microsurgery is the ideal type, with remission of the disease being observed in 80 to 90% of cases. When successful, pituitary microsurgery is followed by preservation of normal pituitary function and restoration of normal hypothalamic-pituitary-adrenal function within 6 to 12 months postoperatively. Medical therapy of Cushing's disease includes drugs that inhibit CRH-ACTH secretion, such as cyproheptadine and bromocriptine, and agents that inhibit cortisol synthesis, such as aminoglutethimide, metyrapone, ketoconazole, and mitotane, or that block the action of cortisol at the glucocorticoid receptor level, such as RU-485. With the exception of mitotane, which has adrenalytic effects, the action of the other pharmacologic agents is promptly reversed when treatment is discontinued. Thus, drug therapy is effective only as temporary treatment for Cushing's syndrome when surgical approaches are contraindicated or when attempts are made to improve the patient's clinical and metabolic status in preparation for surgery. Mitotane is effective in extending survival of patients with adrenal carcinoma, particularly when it is administered early as adjuvant therapy or when it is combined with repeated debulking resection of recurrent tumor. The toxicity associated with mitotane administration limits the use of larger and probably more effective doses in these patients. The synthesis of more specific cytochrome P-450 enzyme inhibitors and of mitotane analogues with more limited toxicity may ultimately provide more effective tools in the pharmacologic management of Cushing's syndrome.     

Cushing's syndrome

Cushing's syndrome results from lengthy and inappropriate exposure to excessive glucocorticoids. Untreated, it has significant morbidity and mortality. The syndrome remains a challenge to diagnose and manage. Here, we review the current understanding of pathogenesis, clinical features, diagnostic, and differential diagnostic approaches. We provide diagnostic algorithms and recommendations for management.     

Cyclic Cushing's syndrome

Because glucocorticoids are necessary to sustain life and maintain homeostasis, adrenal disorders, if not detected in a timely fashion, can have serious consequences. Cyclic Cushing's syndrome is a disease characterized by rhythmic fluctuations in glucocorticoid production. In patients with this disorder, both clinical and biochemical spontaneous remissions may occur and therefore the activity of the hypothalamic-pituitary-adrenal axis between the cycles may be undisturbed. The clinical manifestation of cyclic Cushing's syndrome may be complex and varied, differing not only between patients but also in the same patient on a daily to monthly basis. The presence of cyclic Cushing's syndrome should always be considered in patients with a clinical presentation of hypercortisolism coexisting with normal glucocorticoid plasma levels and a paradoxical response to the dexamethasone test. We here present a detailed case report on a patient diagnosed with cyclic Cushing's syndrome. We report diagnostic and treatment strategies used in our patient and their impact on the course and outcome of the disease.     

Familial Cushing's syndrome

Cushing's syndrome has been demonstrated in four of seven siblings with clinical manifestations appearing around puberty in three of the four siblings. The only other associated findings in these cases were short stature and disturbed carbohydrate metabolism. Adenomatous hyperplasia of the adrenal glands was demonstrated in 3 of the patients, and a virilizing adrenal carcinoma in the fourth sibling. The pathogenesis of the adrenocortical disorders in these siblings is discussed.     

Megestrol-induced Cushing's syndrome

This case describes the first report of a patient developing Cushing's syndrome whilst being treated with the synthetic progestogen, megestrol acetate (Megace). Drugs are the commonest cause of Cushing's syndrome. Some synthetic progestogens are known to have glucocorticoid activity at high doses. On structural grounds neither megestrol nor its major metaboiltes would be expected to interact with the glucocorticoid receptor, though the manufacturers report that it may have ‘weak glucocorticoid activity'.     

Subclinical Cushing's syndrome

Subclinical Cushing's syndrome (CS) is attracting increasing interest since the serendipitous discovery of an adrenal mass has become a rather frequent event owing to the routine use of sophisticated radiologic techniques. Cortical adenoma is the most frequent type of adrenal incidentaloma accounting for approximately 50% of cases in surgical series and even greater shares in medical series. Incidentally discovered adrenal adenomas may secrete cortisol in an autonomous manner that is not fully restrained by pituitary feedback, in 5 to 20% of cases depending on study protocols and diagnostic criteria. The criteria for qualifying subclinical cortisol excess are controversial and presently there is no consensus on a gold standard for the diagnosis of this condition. An increased frequency of hypertension, central obesity, impaired glucose tolerance, diabetes and hyperlipemia has been described in patients with subclinical CS; however, there is still no clear demonstration of the long-term complications of this condition whose management remains largely empirical. Either adrenalectomy or careful observation associated with treatment of the metabolic syndrome have been suggested as treatment options.     

Factitious diseases and Münchausen's syndrome

Factitious diseases in which the symptoms are simulated or created intentionally are very varied: functional manifestations, haemorrhages, anaemia, pyrexia, metabolic disturbances (hypoglycaemia, hypokalaemia, hyperthyroidism, etc.), skin lesions and others. Different symptomatic associations are possible. The Munchausen syndrome which is mainly seen in anglo-saxon countries, is characterised by a long history of factitious symptoms in subjects with psychological profiles which are difficult to define because of the very behaviour of the patients themselves. Besides this syndrome, many psychological disorders have been described in patients presenting with factitious symptoms. One particular form is the creation of factitious diseases in children by their parents. The diagnosis of factitious disease is always difficult and confirmatory proof cannot always be obtained apart from certain cases in which laboratory tests show the presence of drugs in the plasma or urine. Psychotherapy which appears to be essential for these patients is generally very difficult to achieve.     

Factitious Cushing syndrome: two case reports

INTRODUCTION: Search of corticosteroid use is an important precaution before any exploration of hypercorticism. Nevertheless, this use may be factitious leading to serious misdiagnosis and pitfalls. EXEGESIS: We report two cases of 29 and 60 years old male patients, referred for hypercorticism with patent features including metabolic and trophical signs. Laboratories findings revealed unelevated urinary cortisol values (40 and 27 microg/ day) in both cases with normal ACTH and normal plasmatic cortisol response to synacthène (32,5 and 35 microg/dl). Corticosteroid use, initially denied, was finally approved by the patients (hydrocortisone and dexamethasone for the first patient and betametasone for the second). So, they were assigned to psychiatric therapy. CONCLUSION: Our cases emphasize that corticosteroid misuse must be evoked in patients with unexpected hormonal assessment of pituitary adrenal axis despite patent clinical features of hypercorticism. Several specific tests are actually available for detect factitious Cushing syndrome. However, differential diagnostic remains difficult mainly with pseudo Cushing and cyclical Cushing syndromes.