PubMed Health⌕ Search

Biomedical subjects

M Loyo

Publications and source records attributed to M Loyo.

At least 19 recordsLinked to original sources

[Familial pituitary tumor with somatotropic compromise].

Pituitary adenoma, familiar type, with apparent affection over the involved somatomammotropin of secretion of growth hormone and prolactin, with dominant autosomic transmission, is described for the first time. It was seen that a couple of members without demonstrable tumour, showed clinical data (phenotype) of acromegaly. On investigation of histocompatibility antigens it was observed that the patients with tumour and other symptomatic ones, but without tumour, shared the same haplotypes, and so is very possible that investigation of HLA antigens in patients with pituitary tumour, contributes to better identify its nature and frequency.

Acromegaly↗

Long-acting bromocriptine for the acute treatment of large macroprolactinomas.

Six patients with hyperprolactinemia, visual impairment and large macroprolactinoma were treated with a long-acting bromocriptine, in dosage of 50 mg as a single im injection. All patients underwent a full assessment of pituitary prolactin (PRL) secretion before treatment and the studies were repeated about every week during 40 days. Following bromocriptine injection a rapid amelioration of the clinical and visual defects occurred in all patients. Likewise, a significant reduction of the hyperprolactinemia was documented in all six patients and in three of them serum PRL levels reached values as low as 20 ng/ml, and a tumor size reduction was demonstrated by cranial computerized tomography in three of the six cases. No side effects were associated with the administration of bromocriptine. From this study we conclude that the long-acting bromocriptine represents an additional option for the initial management of large prolactinomas in particular when they are associated with severe visual impairment.

Bromocriptine↗

Bromocriptine therapy as pre-operative adjunct of non-functional pituitary macroadenomas.

Although bromocriptine administration produces reduction in size of prolactinomas, its effect upon non-functional pituitary adenomas is still uncertain. Nine patients with macroadenomas, 2 of them with prolactinomas and 7 with non-functional tumours, received bromocriptine prior to transsphenoidal surgery. Size reduction of tumour mass was assessed by computerized tomography and by visual field examination before and following bromocriptine treatment. There were no signs of size diminution or pathological changes in the non-functional adenomas treated pharmacologically during 15 to 360 days. Both patients with prolactinomas had radiological evidence of size reduction and morphological changes on microscopic examination. These 2 patients had tumours with prolactin granules (immunocytochemistry) and adenoma cells showed reduced cytoplasmatic, nuclear and nucleolar areas. Neither vascular damage, cell necrosis, nor infarction was observed by electron microscopy. Patients with non-functional tumours as determined by immunocytochemistry and hormone production did not benefit from bromocriptine. The suggestion that bromocriptine can be used as primary treatment for non-functional pituitary tumours is not supported by the present study. Conversely, in cases of macroprolactinoma, bromocriptine is a useful pre-operative adjunct when surgery is planned and for those patients in whom a surgical cure is considered difficult owing to the tumour size.

Adenoma↗

Mechanisms of hydrocephalus in cerebral cysticercosis: implications for therapy.

Patients with hydrocephalus secondary to cerebral cysticercosis are a highly heterogeneous group. The mechanisms of hydrocephalus in these patients are multiple. Intraventricular cysts may be found in the 3rd and 4th ventricles, the sylvian aqueduct, and the foramen of Monro. Intraventricular cysts can be suspected when the 3rd and 4th ventricles or aqueduct remain enlarged despite shunting. Intraventricular contrast medium demonstrates the presence of the parasites. The intraventricular cysts should be removed surgically. Hydrocephalus due to cisternal cysticercosis can be diagnosed by isotope cisternography. These patients should receive shunts, but the long term prognosis is probably poor. Guidelines for the management of hydrocephalus due to cysticercosis are suggested.

Adult↗

Fourth ventricular cysticercosis.

This is a review of the clinical presentation and results of surgical treatment of 25 cases of cysticercosis of the 4th ventricle. All of the patients presented with hydrocephalus and, after shunting, dilatation of the 4th ventricle persisted while the supratentorial ventricular system returned to its normal size. We propose that, after a shunt procedure is performed, early direct surgical excision of the parasite should be done. Good or excellent results were achieved in 81.4% of the patients. Associated arachnoiditis and vasculitis were the major causes of poor outcomes.

Adult↗

Cardiac arrhythmias associated with subarachnoid hemorrhage: prospective study.

This is a prospective study of cardiac arrhythmias in patients with acute subarachnoid hemorrhage (SAH) secondary to ruptured aneurysm. Twenty per cent of the patients had serious, life-threatening arrhythmias. However, 100% of the patients had some kind of cardiac arrhythmia. The arrhythmias occurred during the first 48 hours after SAH. Such arrhythmias occur in patients without overt, pre-existing heart disease, hypoxemia, or electrolyte imbalance. A prolonged Q-T interval is frequently observed in patients with SAH who develop serious ventricular arrhythmias. (Neurosurgery, 5: 675--680, 1979).

Acute Disease↗

Exercise supplementation to dipyridamole prevents hypotension, improves electrocardiogram sensitivity, and increases heart-to-liver activity ratio on Tc-99m sestamibi imaging.

BACKGROUND: Myocardial perfusion imaging with dipyridamole is an alternative with which to evaluate patients who are unable to exercise. Many patients who undergo dipyridamole testing are limited in their ability, but are not completely unable, to exercise. There are benefits from adding low workload exercise to dipyridamole testing, including a reduction of thallium 201 concentration in the liver, leading to a higher heart-to-liver activity ratio and better image quality. This prospective study was designed to evaluate a protocol of exercise supplementation during dipyridamole technetium 99m sestamibi imaging and to verify whether a higher heart-to-liver activity ratio could be obtained. We also evaluated the potential of this combined protocol to prevent hypotension and induce ischemic changes on the electrocardiogram (ECG). METHODS AND RESULTS: Ninety consecutive patients who were not completely disabled for exercise underwent dipyridamole Tc-99m sestamibi cardiac single photon emission computed tomography with a protocol of exercise supplementation (DipEx). The heart-to-liver activity ratio, hemodynamics, and electrocardiographic changes were studied. The findings were compared with those of a control group (Dip) composed of 99 patients who underwent dipyridamole infusion alone. Patients with left bundle branch block, pacemaker, and atrial fibrillation were excluded. The DipEx patients tolerated the protocol, exercising 4.2 +/- 1.3 minutes on the treadmill (Bruce protocol). Compared with Dip, patients in the DipEx group had a higher heart-to-liver activity ratio (1.3 +/- 0.4 vs 1.6 +/- 0.5, respectively; P =.00001), had no incidence of hypotension (6% vs 0%, respectively; P =.03), and had a higher sensitivity of the ECG to detect ischemia (6% vs 34%, respectively; P =.003). The increase in sensitivity seen in the DipEx group was accompanied by a significant decrease in specificity compared with the Dip group (67% vs 100%, P =.000001). CONCLUSIONS: Our data show that the addition of limited exercise to dipyridamole results in benefits during Tc-99m sestamibi imaging, increasing heart-to-liver activity ratio, preventing vasodilator-induced hypotension, and improving ECG sensitivity for the detection of ischemia. Furthermore, this protocol also provides an estimation of the patient's physical capacity and could be used as an alternative for patients undergoing dipyridamole infusion who are not completely unable to exercise.

Adult↗

Intracranial venous thrombosis in young women.

Twenty women of child-bearing age with intracranial venous thrombosis are reported. Thirteen developed thrombosis post-partum; 6 while on oral contraceptives. In one patient no cause was found. All diagnoses were confirmed by carotid angiography and in 10 out of 14 patients laboratory data indicated a hypercoagulable state. Coagulation studies were performed in 14 normal puerperal women, matched by age, who served as controls. No statistical differences was found between thrombotic and control groups. Radiologic signs of sino-venous occlusion are reviewed. Conservative treatment with anti-edematous agents, anticonvulsants and antiplatelet aggregants is advocated.

Adolescent↗