Acromegaly: A rare disease?

Acromegaly is generally considered a benign and uncommon disease. However, some recent data bring support to the idea that it is more frequent than previously thought. Besides, acromegaly can significantly shorten the length of life due to its cardiovascular and metabolic complications. Since its clinical signs are insidiously progressive for many years, there is a considerable delay in its detection. Usually, many different specialists have been consulted before reaching diagnosis of acromegaly. Those specialists include cardiologists, pulmonologists, dentists, rheumatologists, and diabetes specialists. Possible means to achieve earlier detection are based on increasing awareness of doctors and the public in general. In this paper, the author analyzes the factors related to delayed diagnosis and the potential ways to ameliorate awareness of the disease with particular attention to screening procedures.

[Myxedema coma]. / Coma mixedematoso.

Hypothyroidism is a frequently diagnosed and simply treated disease. If not recognised, however, in time it may develop into the most severe manifestation of hypothyroidism known as myxedema coma. The term "myxedema coma" is generally seen as misleading since most patients do not initially present in a coma. The typical progression is lethargy evolving into stupor and, eventually, into coma with respiratory failure and hypothermia. It mainly affects elderly women, often occurring in winter and is relatively rare. It can be considered a form of decompensated hypothyroidism often triggered by a variety of non-thyroid conditions or diseases provoking an extremely severe condition of multiple system failure with lethal consequences unless an early diagnosis is made and an aggressive treatment is administered.

Implementing a screening program for acromegaly in Latin America: necessity versus feasibility.

INTRODUCTION: Acromegaly is a rare disease with a large burden due its associated comorbidities and the life-long management required. Since the occurrence and severity of associated complications are related to length of exposure to the excess growth hormone seen in acromegaly, early diagnosis is imperative. The delay in diagnosis, however, can be long, and may be the result of a lack of disease awareness and screening programs. Since acromegaly is an uncommon disease, finding ways to increase recognition and diagnosis that would permit early detection in a logical and cost-effective manner could be a challenge. METHODS: We conducted a retrospective literature review for information relating to the screening and diagnosis of acromegaly using PubMed. The aim was to assess whether an acromegaly-screening program in Latin America (and elsewhere) would be both of use and be feasible. FINDINGS AND CONCLUSIONS: An earlier diagnosis allows earlier initiation of treatment, such as surgery and/or drugs, which leads to more successful disease management (biochemical control) and better outcomes. Since the delay in diagnosis can be long, we believe that clear opportunities exist for earlier (and increased) detection of acromegaly. This can be achieved by increasing disease awareness for earlier recognition of symptoms and by using targeted screening (rather than mass screening) programs.

The 10:00-11:00 pm urine cortisol/creatinine ratio. An alternative to late-night salivary cortisol for the diagnosis of Cushing's syndrome.

The aim of this study was to investigate interchangeability of two tests to diagnose Cushing's syndrome. We compared 10:00-11:00 PM urinary free cortisol/creatinine ratio (UFC/Cr) with late night 11:00 PM salivary cortisol (LNSC) in normal and obese controls vs. patients with Cushing's syndrome. Mean UFC/Cr did not differ between 69 normal and 62 obese controls (9.9 ± 7.9 vs. 9.7 ± 9.3) whereas 116 Cushing's patients had significantly higher values (277.0 ± 318.0; z: -11.1 and -10.2, respectively; p < 0.001). LNSC was 1.9 ± 1.2 nmol/l in 44 normal and 2.5 ± 1.6 in 45 obese subjects with no differences between them, but was significantly higher in 47 Cushing's patients (24.8 ± 23.3; z: -7.22 and -6.96, respectively, p < 0.001). Comparison of UFC/Cr and LNSC in samples obtained simultaneously showed that UFC/Cr was 12.0 ± 8.7 ng cortisol/mg creatinine in 34 normal, 12.3 ± 8.9 in 40 obese and 319.5 ± 333.4 in 35 CS subjects (p < 0.001 vs. normal and obese), whereas LNSC was 1.8 ± 1.2 nmol/l in normal, 2.6 ± 1.7 in obese and 24.6 ± 17.4 in CS patients (p < 0.001 vs. normal and obese); ROC curves showed comparable high sensitivity and specificity figures for the diagnosis of CS. We concluded that UFC/Cr test is easy to perform, readily available in routine laboratories, has high sensitivity and specificity, and offers a valuable alternative to LNSC in the study of Cushing's syndrome.

Aggressive tumors and difficult choices in acromegaly.

PURPOSE: The current article looks at some of the factors associated with pituitary adenomas displaying unusually aggressive biological and clinical behaviour in patients with acromegaly. METHODS: This was a retrospective, narrative review of previously published evidence chosen at the authors' discretion and presented from the perspective of a Latin American case study. FINDINGS AND CONCLUSIONS: Although most pituitary tumors in acromegalic patients are benign and non-aggressive many can behave more aggressively, compromising local surrounding structures. These lesions tend to respond poorly to somatostatin analogs, have a higher risk of recurrence after surgery and, thus, a worse prognosis. Patients with more aggressive tumors constitute a particular challenge, as they often require several therapeutic approaches and may be difficult to manage, especially when options are restricted due to limited resources.

A practical approach to acromegaly management in Latin America.

INTRODUCTION: Evidence-based treatment guidelines have undoubtedly advanced medical practice and supported optimal management of acromegaly, but their application may be hampered by limited access to the latest treatment options. METHODS: In this retrospective, narrative review, the authors revisited existing treatment guidelines for acromegaly in Latin America. These were considered in conjunction with published evidence chosen at the authors' discretion. FINDINGS: In a socially and economically diverse region, such as Latin America, any regional practice guidelines need to appreciate that recommended treatment options, such as surgery by expert pituitary surgical teams and drug therapies, especially somatostatin analogs, are often not available due to limited resources. In these instances, physicians may be obliged to apply less effective therapeutic options. CONCLUSIONS: The current article looks at the practical aspects of acromegaly management in Latin America and discusses this in the context of existing guidelines. Furthermore, we consider potential strategies to make better use of resources through combination and multimodal approaches to treatment.

[Non-autoimmune thyroiditis]. / Tiroiditis no-autoinmunes.

The term thyroiditis comprises a group of thyroid diseases characterized by the presence of inflammation, including autoimmune and non-autoimmune entities. It may manifest as an acute illness with severe thyroid pain (subacute thyroiditis and infectious thyroiditis), and conditions in which the inflammation is not clinically evident evolving without pain and presenting primarily thyroid dysfunction and/or goiter (drug-induced thyroiditis and Riedel thyroiditis). The aim of this review is to provide an updated approach on non-autoimmune thyroiditis and its clinical, diagnostic and therapeutic aspects.

[Female hyperandrogenemia and normal serum levels of testosterone and sex hormone binding globulin]. / Hiperandrogenemia femenina y niveles séricos normales de testosterona y globulina ligadora de esteroides sexuales.

It is well known that the reference values usually employed for endocrine biochemical measurements are those suggested by the suppliers of commercial kits despite their advice that each laboratory should set its own reference values. Our objectives were to (i) determine reference ranges for serum testosterone (T) and sex hormone binding globulin (SHBG) appropriate to our laboratory and population, and (ii) to analyze their influence on evaluating hyperandrogenemia. SHBG and T were measured, and free and bioavailable testosterone calculated, in (a) 30 selected non-hyperandrogenic women, (b) 87 non-selected healthy female blood donors, (c) 53 women with hyperandrogenism, and (d) 38 women with hyperandrogenic disorders but without biochemical hyperandrogenemia according to normal ranges suggested by the kit manufacturer. Mean serum SHBG concentrations were significantly different among all four groups. SHBG levels were significantly higher in selected normal women (group a). Using our results for this selected control group as new reference values, 12 out of 38 (31.6%) women with hyperandrogenic disorders without apparent hyperandrogenemia (group d) were recategorized as hyperandrogenemic. Similarly, 4 out of 63 (6.4%) non-selected, normal weight, women (group b), were recategorized as hyperandrogenic. Therefore, the diagnosis of hyperandrogenemia would improve accuracy by using customized reference SHBG values instead of those suggested by the suppliers.

[A critical analysis of cortisol measurements: an update]. / Medición de cortisol y sus fracciones. Una puesta al día.

Serum cortisol measurement is a very useful tool in the biochemical evaluation of adrenocortical function. Since this hormone circulates in blood mainly linked to binding globulins but is also partially free, it can be measured not only in the blood but also in urine, saliva and other biological fluids and tissues. Basal determinations as well as dynamic testing may be performed to evaluate the circadian variations, to estimate the diurnal cortisol secretion and to analyze its relations with other components of the hypothalamic-pituitary-adrenal axis. Measurements of cortisol in blood, saliva and urine may reflect the cortisol secretion at the time of sample collection or during a 24 h span. Recently, it has been proposed the determination of cortisol in tissues such as hair and nails like a means of evaluating the hormonal status during prolonged periods. The aim of this paper is to update the methodology for measuring cortisol and its usefulness for the clinical diagnosis of troubles of the hypothalamic-pituitary-adrenal axis.

[Pseudo-pituitary tumor and hypopituitarism secondary to a sphenoid sinus inverted papilloma]. / Pseudo-tumor pituitario e hipopituitarismo secundario a un papiloma invertido del seno esfenoidal.

Inverted papilloma (IP) is a benign uncommon epithelial tumor, arising mostly from the lateral nasal wall. Though benign, this lesion is highly invasive into surrounding tissues and malignant transformation may occur. Primary IP of the sphenoid sinus and intracranial extension with dural invasion, even without histological evidence of malignancy, has only rarely been described. Hypopituitarism as a complication of this lesion has never been reported. We describe the case of a 59-year-old woman who was evaluated because of a 5-year-history of severe headaches and abnormalities in the visual field. Magnetic resonance imaging (MRI) showed a 1.4 per 2.0 cm heterogeneous sellar lesion with suprasellar and sphenoid sinus extension, eroding the sellar floor with optic chiasm compression. Otolaryngologists gave her 16 mg/day of prednisone during approximately 3 months with a near total regression of the mass on MRI. The endocrine biochemical evaluation showed pituitary gonadal, thyroid and adrenal insufficiency. A new MRI showed growth of the tumor with obliteration of the sphenoid sinus. An endoscopic sinus biopsy revealed an IP, so a transnasal endoscopic sinus surgery was performed with complete resection evidenced by MRI a year later.

[Amiodarone and thyroid dysfunction]. / Amiodarona y disfunción tiroidea.

Amiodarone is a structural analogue of thyroid hormone, and some of its anti-arrhythmic actions and toxicity are attributable to its interaction with nuclear receptors of thyroid hormones. Being highly lipophilic, amiodarone is concentrated in many tissues and is eliminated, consequently, very slowly. It is preferably employed to manage life-threatening arrhythmias, including ventricular fibrillation and unstable ventricular tachycardia. Other indications include atrial fibrillation and flutter, severe congestive heart failure, prevention of atrial fibrillation recurrence, and even in emergency medical situations to prevent sudden cardiac death. The aim of this review is to provide an updated approach on amiodarone and its influence on thyroid physiology and to discuss and analyze in depth its potential and not infrequent thyroidal adverse effects such as hypothyroidism and thyrotoxicosis.

Management of acromegaly in Latin America: expert panel recommendations.

Although there are international guidelines orienting physicians on how to manage patients with acromegaly, such guidelines should be adapted for use in distinct regions of the world. A panel of neuroendocrinologists convened in Mexico City in August of 2007 to discuss specific considerations in Latin America. Of major discussion was the laboratory evaluation of acromegaly, which requires the use of appropriate tests and the adoption of local institutional standards. As a general rule to ensure diagnosis, the patient's GH level during an oral glucose tolerance test and IGF-1 level should be evaluated. Furthermore, to guide treatment decisions, both GH and IGF-1 assessments are required. The treatment of patients with acromegaly in Latin America is influenced by local issues of cost, availability and expertise of pituitary neurosurgeons, which should dictate therapeutic choices. Such treatment has undergone profound changes because of the introduction of effective medical interventions that may be used after surgical debulking or as first-line medical therapy in selected cases. Surgical resection remains the mainstay of therapy for small pituitary adenomas (microadenomas), potentially resectable macroadenomas and invasive adenomas causing visual defects. Radiotherapy may be indicated in selected cases when no disease control is achieved despite optimal surgical debulking and medical therapy, when there is no access to somatostatin analogues, or when local issues of cost preclude other therapies. Since not all the diagnostic tools and treatment options are available in all Latin American countries, physicians need to adapt their clinical management decisions to the available local resources and therapeutic options.

[Therapeutic management in 154 acromegalic patients]. / Enfoque terapéutico en 154 pacientes con acromegalia.

Acromegaly is a chronic, invalidating disease due in over 95% of cases to a growth hormone (GH) secreting pituitary adenoma. Its clinical manifestations are associated to local complications related to the tumor growth and/or to the metabolic consequences of GH excess. We report here our experience on 154 acromegalic patients. Surgical remission rate using stringent biochemical criteria was 32%, a figure relatively low due to the great number of patients bearing macroadenomas with invasive complications. Primary or adjuvant radiotherapy was able to obtain normalization of biochemical parameters in as much as 65.4% of treated patients. In only 14.0% of acromegalics drug therapy with dopaminergic agents was effective in controlling the disease. By contrast, somatostatinergic analogues were more effective, obtaining a clinical and biochemical remission in 45.7% of the patients. In summary, multimodal therapy of acromegaly can lead to a global safe control of the disease in 55.2% of the cases. The ongoing development of new drugs represents promising alternatives in the management of this disabling condition.

[Analysis of a pituitary adenoma registry]. / Análisis de un Registro de adenomas pituitarios.

Collection and analysis of data obtained during the clinical treatment of pituitary tumours are of great utility in the decision making process, when facing clinical situations. We report here data on 519 from 670 patients with pituitary adenomas obtained from a computerized registry. Three hundred and forty five were females (66%) and 174 males (34%), aged 14-80. Final diagnosis was acromegaly in 176, Cushing's disease in 153, prolactinoma in 101 and clinically non-functioning adenoma in 89. Mean age at diagnosis was 43.9 ± 13.5 (16-80) for acromegalics, 35.7 ± 12.9 (14-72) for Cushing's, 30.0 ± 13.4 (15-79) for prolactinoma and 52.1 ± 15.2 (17-79), for non-functioning tumours. The setup of an institutional registry on pituitary tumours constitutes a useful tool to analyze clinical experience, optimize the cost/benefit ratio of procedures used for diagnosis and to ameliorate therapeutic strategies, improving patient's care. It greatly contributes to teaching medical students as well as to post-graduate physicians and provides a basis for developing clinical research.

High prevalence of thyroid disorders in relatives of patients with familial papillary thyroid cancer.

In the familial form of papillary thyroid cancer (PTC), two or more members of the same family have to be affected with PTC. Prevalence is around 5% of all PTC. We performed a clinical analysis in 79 relatives of 16 patients of 7 unrelated kindred with the diagnosis of familial papillary thyroid carcinoma (FPTC). The results were compared with a control group. Thyroid palpation and TSH and TPO-Ab assessment was carried out in the relatives without a diagnosed PTC. Additionally, molecular analysis was performed in the sixteen affected patients. Clinical screening of the 79 family members showed the presence of goiter in 22/79 (29 %). This frequency was much higher than that observed in the control group (8.7%), p < 0.001. Hypothyroidism was found in 4 of the relatives (5%) vs. 2.5% observed in the control group, p < 0.01, and anti-thyroid antibodies (TPO-Ab) were positive in 14% of the relative's group vs. 10 % in the control group, (p = NS). In the molecular analysis, only a protooncogene TRK rearrangement was observed in family # 6. In conclusion, we found a higher incidence of goiter and hypothyroidism in the relatives of patients with FPTC. Nevertheless, TPO-Ab frequency was not different. No molecular abnormalities were indicative of a specific pattern in this subset of patients with FPTC.

[Long-term survival after small doses of radioiodine therapy for brain metastases of thyroid cancer]. / Supervivencia prolongada luego de pequeñas dosis de terapia con radioyodo en metástasis cerebral de cáncer de tiroides.

Differentiated thyroid cancer is generally accompanied by a long term survival. However, in some cases distant metastases can develop and among them, brain localizations are of poor prognosis. The aim of this presentation is to communicate the clinical case of a 65 year-old woman who consulted for diplopia in vertical gaze which had appeared one month earlier. MRI showed a big mass at the level of the occipital condyle. Diagnosis of primary brain tumor was made so she was operated twice with incomplete tumor resection. The pathological study was confirmatory of a metastatic lesion of thyroid carcinoma. A total thyroidectomy with resection of a papillary cancer of the follicular variant was performed. Then, she was successfully treated with small repetitive radioiodine amounts for a total accumulated dose of 325 mCi 131I, with a long-term survival.

El cáncer diferenciado de tiroides generalmente se acompaña de una supervivencia a largo plazo. Sin embargo, en algunos casos pueden desarrollarse metástasis a distancia y, entre ellas, las localizaciones cerebrales son de mal pronóstico. El objetivo de esta presentación es comunicar el caso clínico de una mujer de 65 años que consultó por diplopía en la mirada vertical que había aparecido un mes antes. La resonancia magnética mostró una gran masa a nivel del cóndilo occipital. Se realizó el diagnóstico de tumor cerebral primario, por lo que fue operada dos veces con resección tumoral incompleta. El estudio histopatológico confirmó una lesión metastásica de carcinoma de tiroides. Se realizó una tiroidectomía total con resección de un cáncer papilar de la variante folicular. Luego, fue tratada con éxito con pequeñas cantidades repetitivas de yodo radiactivo para una dosis total acumulada de 325 mCi 131I, con una supervivencia a largo plazo.

In what clinical settings should Cushing's syndrome be suspected?

Despite its low frequency, endogenous Cushing's syndrome is not an exceptional clinical entity. A growing number of cases are currently derived to specialized centers suggesting an increasing knowledge of the clinical features of hypercortisolism by specialists of diverse branches of clinical medicine. Clinical signs derive from an exaggeration of the physiological actions of cortisol inducing protein breakdown, hyperglycemia, fat mobilization, dyslipidemia, hydrosaline retention, immunosuppression and increased susceptibility to infection. Despite its low specificity, symptoms such as unexplained development of central obesity, mood changes, fatigue, weakness, myopathy, easy bruisability, red striae, arterial hypertension, diabetes and hyperlipidemia, are suggestive of the diagnosis. From an epidemiological point of view, Cushing's syndrome is to be suspected and consequently searched for among patients with uncontrolled high blood pressure or diabetes mellitus, metabolic syndrome, polycystic ovarian syndrome, osteoporosis, depression or adrenal incidentaloma. True Cushing's syndrome has to be differentiated from pseudo syndromes. Most sensitive physical signs for discriminating Cushing's syndrome from pseudo-Cushing states are the presence of supraclavicular fat pads, myopathy, thin skin and easy bruising. The recognition of the clinical manifestations of Cushing's syndrome and of the sub-populations at risk of contracting the disease should be improved through medical education at the medical school and at postgraduate levels. Clinical detection of Cushing's syndrome must be performed mainly by non-endocrinologists, yet its etiological diagnosis and therapeutic management is to be carried out in highly experienced and specialized centers, to ensure the best results in the treatment of this really challenging endocrine disturbance.

Long-term outcome after bilateral adrenalectomy in Cushing's disease with focus on Nelson's syndrome.

OBJECTIVE: We analyzed the clinical, biochemical, and imaging findings of adrenalectomized patients with Cushing's disease (CD) in order to compare the characteristics of those who developed Nelson's syndrome (NS) versus those who did not develop this complication (NNS), aiming to identify possible predictive factors for its occurrence. SUBJECTS AND METHODS: We performed a retrospective review of the clinical records of a group of patients with CD who underwent TBA between 1974 and 2011. RESULTS: Out of 179 patients with CD, 13 (7.3%) underwent TBA. NS occurred in 6 of them (46%) after a mean of 24 months from the total bilateral adrenalectomy (TBA). Age at diagnosis, duration of Cushing's syndrome (CS) until TBA, and steroid replacement doses were similar in both groups. Initial urinary cortisol levels (24-hour urinary free cortisol [UFC]) were significantly higher in the NS group than in the NNS group (p = 0.009). Four patients in the NS group and three of those in the NNS group received radiotherapy before TBA (p = 0.26). Three patients in the NS group presented residual tumors before TBA, compared with none in the NNS group (p = 0.04). At 1 year after TBA, the median ACTH level was 476 ng/L (240-1500 ng/L) in the NS group and 81 ng/L (48-330 ng/L) in the NNS group (p = 0.0007). CONCLUSION: In conclusion, a residual tumor before TBA, higher 24-hour UFC at diagnosis, and increasing ACTH levels within 1 year after TBA emerged as predictive factors of development of NS.