Diagnosis and treatment of neuroendocrine tumors - A series of 13 clinical cases (2014-2017)

Paragangliomas and pheocromocytomas are rare neuroendocrine tumors with different clinical presentation, being responsible for secondary arterial hypertension with target-organ lesions. Surgery is a curative therapy in these tumors and demands a multidisciplinary approach. These tumors are more frequent between the 4th and 5th decades of life and their clinical manifestations are related to catecholamines production: headache, palpitations, variable blood pressure. This article presents 13 clinical cases of patients with neuroendocrine tumors, with an median-age of 56,7 years, submitted to surgery between 2014 and 2017. The diagnosis was made based on clinical suspicion, serum and urinary catecholamines and metanephrins, imagiologic evaluation with CT or abdominal and pelvic MRI and MIBG scintigraphy. After surgery, the majority of patients remained with normal blood pressure, without anti-hypertensive therapy and follow-up was maintained in Outpatient Clinic, with periodic blood tests and imaging reevaluation.

Wavelet analysis of autonomic outflow of normal subjects on head-up tilt, cold pressor test, Valsalva manoeuvre and deep breathing

Non-invasive autonomic evaluation has used fast Fourier transform (FFT) to assign a range of low (LF) and high frequencies (HF) as markers of sympathetic and parasympathetic influences, respectively. However, FFT cannot be applied to brief transient phenomena, such as those observed on performing autonomic tests where the acute changes of cardiovascular signals (blood pressure and heart rate) that represent the first and most important stage of the autonomic performance towards a new state of equilibrium occur. Wavelet analysis has been proposed as a method to overcome and complement information taken exclusively in the frequency domain. With discrete wavelet transform (DWT), a time-frequency analysis can be done, allowing the visualization in time of the contribution of LF and HF to the observed changes of a particular signal. In this study, we evaluate with wavelets the acute changes in R-R intervals and systolic blood pressure that are observed in normal subjects during four classical autonomic tests: head-up tilt (HUT), cold pressor test (CPT), deep breathing (DB) and Valsalva manoeuvre (VM). Continuous monitoring of ECG and blood presure was performed. Also LF, HF and LF/HF were calculated. Consistent with previous interpretations, data showed an increase of sympathetic activity in HUT, CPT and VM. On DB, results reflected an increase in parasympathetic activity and frequencies. In conclusion, when compared with FFT, wavelet analysis allows the evaluation of autonomic variability during short and non-stationary periods of time and may constitute a useful advance in the assessment of autonomic function in both physiological and pathological conditions.

Tachycardiomyopathies

Heart failure is a common disease with major social and economic repercussions for the health system. All potentially curable or reversible causes of heart failure should be investigated and treated if possible. Several experimental and clinical studies have demonstrated that supraventricular tachycardias can induce a form of dilated cardiomyopathy (tachycardiomyopathy), which may be reversible with ventricular frequency response control. In this article we present a clinical case, and review this clinical entity, so often underdiagnosed.

New transthyretin mutation V28M in a Portuguese kindred with amyloid polyneuropathy

A 62-year-old Portuguese man, with no history of familial amyloid polyneuropathy (FAP), and a 2(1/2)-year history of tingling in the toes and sexual dysfunction was found neurophysiologically to have a sensory-motor axonal polyneuropathy. Autonomic tests showed slight sympathetic and marked parasympathetic involvement. Heart, kidney, and eyes were normal. Single strand conformation polymorphism (SSCP) mutation analysis for the transthyretin (TTR) gene was performed. The SSCP pattern suggested the presence of a mutation in exon 2, but was different from the pattern observed for a control representing the most common TTR mutation associated with FAP, i.e., TTR V30M. DNA sequencing analysis revealed an A-to-G transition in the first base of codon 28 normally encoding a valine, giving rise to a methionine residue. The presence of this extra methionine was confirmed by peptide mapping and mass spectrometry analysis. Biopsy of nerve and skin of the propositus showed amyloid deposits that were immunoreactive for TTR. This is a new variant TTR related to late-onset amyloid neuropathy with autonomic dysfunction. This case confirms that TTR mutation screening should be considered in patients with a clinical disorder consistent with amyloid neuropathy even in the absence of a family history.

[Atypical radiologic features of pulmonary tuberculosis. Nodular images in strings of balloons]

Chest radiographs are an important tool for the diagnosis and follow-up. Yet the radiographic findings can vary significantly, ranging from the so-called usual to unusual patterns. In this paper the authors report three cases of pulmonary tuberculosis in which the chest radiographs showed a nodular, pseudo-tumoral pattern. Based on literature and on their own experience, the authors discuss the frequency of this radiologic presentation in this setting and its correlation with the immunological status of the patient, the pathogenicity of Mycobacterium tuberculosis and the clinical presentation of the disease.

[Orthostatic tachycardia syndromes]

Orthostatic tachycardia may be due to several physiologic abnormalities. Normal regulation of cardiac frequency in relation to postural changes is described; main causes of orthostatic tachycardia are described, in particular hypovolemia, beta-adrenergic hypersensitivity and segmental autonomic neuropathy. The current therapeutic attitudes are discussed.

[Assessment of cardiovascular reflexes in patients with mitral valve prolapse syndrome]

OBJECTIVE

Functional evaluation of Autonomic Nervous System in patients with Mitral Valve Prolapse Syndrome.

DESIGN

Study of cardiovascular reflexes.

SETTING

Out patients studied in the Laboratory for Study of Autonomic Nervous System Function of Santa Maria Hospital, Lisbon, Portugal.

MATERIAL AND METHODS

We studied 20 patients with clinical and echocardiographic diagnosis of mitral valve prolapse, who presented Mitral Valve Prolapse Syndrome, without significant mitral regurgitation, and with normal left ventricular function. Cardiovascular reflexes were analysed by mean of five tests.

RESULTS

In 75% of the cases, patients had results according to vagal hypofunction. Orthostatic hypotension was present in 40%. Among patients with orthostatic hypotension, 75% had postural phenomena. Among patients with postural phenomena, 75% had orthostatic hypotension.

CONCLUSIONS

In the present study, patients behaviour hasn't been uniform. Vagal hypofunction was present in 75% and orthostatic hypotension in 40% of the cases. A relation has been found between orthostatic hypotension and postural into.

[Pure autonomic failure]

We present the case of a 64-year-old woman who, in the past 5 years, complained of constipation/diarrhea, hyposudoresis, xerostomia and xerophthalmia, dysuria and orthostatic hypotension. Cardiovascular reflexes analysis revealed sympathetic and parasympathetic failure. Norepinephrine was markedly reduced, both lying and after tilt. Norepinephrine infusion determined a significant rise in blood pressure, allowing the diagnosis of denervation hypersensitivity. The diagnosis of pure autonomic failure was made. Therapy with 9 alpha fludrocortisone and metoclopramide was initiated with marked and sustained symptomatic effect.