Orwik

Obstructive sleep apnoea and the orexigenic pathway in type 2 diabetes.

Iodine-131 therapy for hyperthyroidism prescribed by endocrinologist - our preliminary experience.

INTRODUCTION: Radioiodine (I-131) is a useful therapeutic modality of hyperthyroidism when medical therapy fails. Traditionally, the nuclear physicians undertake the prescription of I-131 therapy. However, endocrinologists are increasingly being reco... expand abstractgnized for their competence in prescribing individualized doses of I-131 for the treatment of various thyroid disorders. METHODS: In this pilot prospective study, we collaborated with our nuclear medicine colleagues to determine the outcomes of 80 patients with hyperthyroidism who underwent I-131 ablation as prescribed by the endocrinologist. Doses administered were based primarily on thyroid volume with adjustments contingent on adverse factors, and fixed assumptions on target absorbed dose (R) and uptake (U) were used. Seventy-three had Graves' disease (GD) and seven had toxic nodular goitre (TNG) or toxic adenomas (AFTN). Therapeutic success was defined as achievement of hypothyroidism or euthyroidism. RESULTS: 95.9 percent (70 of 73) of GD patients and 85.7 percent (6 of 7) of those with TNG/AFTN achieved successful outcomes after a single dose of endocrinologist-directed I-131 therapy. More than 50 percent of patients became hypothyroid by three months and about two-thirds became hypothyroid by six months post I-131 therapy. CONCLUSION: Our results indicate that the success rate of endocrinologist-directed I-131 therapy exceeds 95 percent with a single dose and compares favourably with nuclear physician-directed therapy outcomes. collapse abstract

High iodine (substrate) turnover Graves' disease: the intriguing 'rapid responder' variant of thyrotoxicosis.

Factors determining the responsiveness to antithyroid drugs (ATDs) in Graves' disease are not fully known. Notwithstanding the typical pattern and tempo of thyroid hormone responses to thionamides, the existence of an unusual subset of Graves' diseas... expand abstracte with extraordinarily rapid thyroid hormone responses to ATDs will prove challenging even to the expert clinician. Termed 'rapid responder Graves' disease' or 'high turnover Graves' disease', the serum thyroxine (FT4) and triiodothyronine (FT3) of patients with this variant of thyrotoxicosis can decline precipitously during the initiation of ATDs and yet escalate acutely upon discontinuation of pharmacological intervention. We describe a case that presented with low serum FT4 and FT3 in association with suppressed serum thyrotropin (TSH) concentrations soon after starting carbimazole even at a low dose. The erratic clinical course comprising largely of serum FT4 nadirs and peaks is elaborated to facilitate appreciation of the difficulty in the stabilization of the thyroid with ATDs. The possible pathogenetic mechanisms for the chaotic fluctuations in thyroid hormones to minor changes in thionamide dose adjustments are discussed as well. collapse abstract

Pituitary abscess: our experience with a case and a review of the literature.

Pituitary abscess is a rare disease. Due to its potentially high mortality and morbidity rate, it should be considered in the differential diagnosis of sellar masses. Despite recent advances in radiological investigations, making a definitive diagnos... expand abstractis preoperatively remains challenging. This 45-year-old Indian gentleman presented with severe throbbing headache for six months. Magnetic resonance imaging of the brain revealed a sellar mass with peripheral enhancement that was misdiagnosed as a pituitary macroadenoma. A trans-sphenoidal excision was done, which surprisingly yielded only pus that was drained accordingly from the lesion. Fungal and bacterial cultures were negative. However this patient subsequently lost complete function of the pituitary gland, resulting in central diabetes insipidus and required permanent hormonal replacement therapy in the deficient endocrine axes. A Medline search was conducted and a review of 24 cases reported in the last 5 years discussed. collapse abstract

Thyrotoxicosis and acute abdomen--still as defying and misunderstood today? Brief observations over the recent decade.

BACKGROUND: Clinicians managing thyrotoxic patients with acute abdomen face challenging diagnostic and risky therapeutic dilemmas. AIM: To analyse the frequency of medical vs. surgical acute abdomen, and to characterize the poorly understood thyrotox... expand abstractic medical acute abdomen phenomenon. DESIGN: Retrospective review of case notes. METHODS: All case files with a simultaneous diagnosis of thyrotoxicosis and acute abdomen admitted between 1994 and 2004 were traced and audited. RESULTS: Thirteen had a history of thyrotoxicosis while 12 were newly diagnosed. The commonest cause was Graves' disease. Twenty-three (92%) cases were thyrotoxic, of whom six (24%) had thyroid crisis, while two (8%) had subclinical thyrotoxicosis. The provisional diagnosis of acute abdomen was correct in 14 cases (56%), but discordant with the final diagnosis in 11 cases (44%). Eight cases (32%) without any demonstrable pathology were medical, vs. four (16%) with surgical acute abdomen, while 11(44%) had gastritis, hepatobiliary-pancreatic disorders or diverticulitis conservatively managed. The epigastrium and/or central abdomen (72.7%) were the commonest affected regions in medical acute abdomen. CONCLUSION: Although the majority of acute abdomen in thyrotoxicosis was medical in nature, our experience indicates that surgical conditions were not uncommon. Thus, serious causes requiring life-saving surgery should be excluded before attributing it to medical acute abdomen. collapse abstract

Multiple endocrinopathies associated with lithium therapy.

OBJECTIVE: To illustrate a case of lithium-associated primary hyperparathyroidism, thyrotoxicosis, and nephrogenic diabetes insipidus and to discuss the potential mechanisms for these complications. METHODS: We describe the clinical and laboratory fi... expand abstractndings in our current patient and review the related medical literature. RESULTS: A 65-year-old Chinese woman with bipolar affective disorder, who had received maintenance lithium therapy for 10 years, was seen in an acute care hospital because of fever and confusion. Investigations showed that she had primary hyperparathyroidism and hyperthyroidism. She underwent a parathyroidectomy, which revealed a parathyroid adenoma. Her initial subclinical hyperthyroidism evolved into overt hyperthyroidism after use of lithium was discontinued. Therapy was initiated with carbimazole, which was up-titrated briefly; the patient was subsequently weaned off this medication. Her postoperative course was complicated by persistent polyuria in conjunction with a negative fluid balance, consistent with nephrogenic diabetes insipidus. Thus, amiloride therapy was instituted. The results of an objective causality assessment suggested that the primary hyperparathyroidism, hyperthyroidism, and nephrogenic diabetes insipidus were possibly or probably related to the lithium therapy. CONCLUSION: Lithium remains an intriguing drug with numerous potential endocrinologic complications. It is important that clinicians prescribing lithium are aware of its side effects and have a strategy for their detection and management. collapse abstract

Molecular pathways linking the pheochromocytoma susceptibility genes.

Isolated adrenal mass in cachectic patients-don't forget malignant pheochromocytoma.

Configuration of the hemoglobin oxygen dissociation curve demystified: a basic mathematical proof for medical and biological sciences undergraduates.

The oxygen dissociation curve (ODC) of hemoglobin (Hb) has been widely studied and mathematically described for nearly a century. Numerous mathematical models have been designed to predict with ever-increasing accuracy the behavior of oxygen transpor... expand abstractt by Hb in differing conditions of pH, carbon dioxide, temperature, Hb levels, and 2,3-diphosphoglycerate concentrations that enable their applications in various clinical situations. The modeling techniques employed in many existing models are notably borrowed from advanced and highly sophisticated mathematics that are likely to surpass the comprehensibility of many medical and bioscience students due to the high level of "mathematical maturity" required. It is, however, a worthy teaching point in physiology lectures to illustrate in simple mathematics the fundamental reason for the crucial sigmoidal configuration of the ODC such that the medical and bioscience undergraduates can readily appreciate it, which is the objective of this basic dissertation. collapse abstract

A mathematical model of pituitary--thyroid interaction to provide an insight into the nature of the thyrotropin--thyroid hormone relationship.

The mathematical model proposed focuses on the description of the behavior of the interaction between thyrotropin (i.e. thyroid-stimulating hormone (TSH)) and thyroid hormones with the objective of providing a better understanding of the behavior of ... expand abstractTSH-T4 relationship in health and in disease. The normal pituitary-thyroid axis is tightly coupled and regulated with a servomechanism. In the physiological situation, any elevation of thyroid hormones will inhibit TSH secretion by the thyrotrophs of the pituitary, which in turn lead to an appropriate reduction in stimulation of the thyroid, accompanied by a decline of thyroid hormones towards normal. Similarly, a decline in thyroid hormones represents a potent input signal that when sensed by the pituitary thyrotrophs, will result in an increase of TSH output by the latter to accelerate the synthesis and secretion of thyroid hormones to drive the state towards normal equilibrium. Using this model, the profound sensitivity of thyrotrophs to feedback by thyroid hormones can be appreciated and understood better in the context of diseases of thyroid hormone excess and deficiency. collapse abstract

Catecholamine and metanephrine excess in intracerebral haemorrhage: revisiting an obscure yet common "pseudophaeochromocytoma".

The enigmatic duality of high-density lipoprotein-cardioprotective yet potentially atherogenic: comment on the article by McMahon et al.

Controversial endocrine interventions for the aged.

Specific endocrine changes occur with the ageing process. The last decade has witnessed significant progress in the basic and clinical science of ageing, thereby rejuvenating the interest in anti-ageing medicine, especially that of hormone replacemen... expand abstractt, by medical professionals and the lay public. However, endocrine manipulation as a therapeutic strategy for ageing is still evolving as continuing research attempts to answer the many questions of what it can achieve at the risk of incurring unknown long-term adverse effects. The current day doctor is confronted with a host of options, and will benefit from a synopsis of the latest evidence before making the most appropriate decision for aged patients seeking hormonal replacement therapy as a means to counter the effects of ageing. This review aims to give a rapid overview of the endocrine profile of geriatric population and the studies on the more controversial hormonal replacement therapies for the aged. collapse abstract

Association of polycystic ovary syndrome and fibromyalgia in a patient with primary hyperparathyroidism: a novel triad?

Quality of life and psychological status in survivors of severe acute respiratory syndrome at 3 months postdischarge.

BACKGROUND: Little is known about the long-term consequence of severe acute respiratory syndrome (SARS). We carried out an assessment on SARS patients after their recovery from their acute illness. METHOD: Postal survey comprising Health-Related Qual... expand abstractity of Life (HRQoL) questionnaires and anxiety and depression measures was sent to them at 3 months' postdischarge. RESULTS: There was a significant impairment in both the HRQoL and mental functioning. Forty-one percent had scores indicative of a posttraumatic stress disorder (PTSD); about 30% had likely anxiety and depression. CONCLUSION: SARS has significant impact on HRQoL and psychological status at 3 months. collapse abstract

Calcinosis cutis with siliconomas complicated by hypercalcemia.

OBJECTIVE: To report a case of extensive calcinosis cutis presumably caused by silicone injections, which was complicated by hypercalcemia. METHODS: A long-standing case of calcinosis cutis with subsequent development of hypercalcemia is presented, a... expand abstractnd possible mechanisms for the underlying metabolic dysfunction are discussed. RESULTS: A 78-year-old woman presented with severe hypercalcemia and was found to have extensive subcutaneous calcifications on the anterior chest wall and abdomen, likely related to previous silicone injections. The hypercalcemia was treated with intravenously administered pamidronate and aggressive rehydration. Resection of the extensive long-standing calcific deposits was not a viable option. The hypercalcemia resolved with treatment, but the patient died of urinary tract sepsis. CONCLUSION: Extensive calcinosis cutis can result in hypercalcemia, possibly attributable to granulomatous reaction and vitamin D excess. collapse abstract

Potentially fatal paracetamol overdose and successful treatment with 3 days of intravenous N-acetylcysteine regime--a case report.

INTRODUCTION: Paracetamol overdose is the most common drug overdose worldwide. To our knowledge, the maximum number of paracetamol tablets ingested reported in the literature is 45 g. CLINICAL PICTURE: We describe a 21-year-old patient who acutely in... expand abstractgested 120 tablets, each 500 mg paracetamol (i.e., 60 g equivalent to 1200 mg/kg body weight) in a suicidal attempt. Our patient also drank 2 bottles of codeine-based cough syrup equivalent to 360 mg of codeine. At 6 hours post ingestion, her serum paracetamol level was 207 mg/L. The poor prognostic factors for paracetamol overdose in our patient included massive paracetamol ingestion (confirmed by blood levels), codeine co-ingestion and elevated serum amylase (189 U/L). TREATMENT: She was treated with a 3-day modified regimen of intravenous N-acetylcysteine. OUTCOME: The liver function tests and the prothrombin time remained normal over the second and third day of admission and the patient was discharged without complications on the fifth day. CONCLUSION: From this experience we feel that in very severe paracetamol poisoning, a modified regime of intravenous N- acetylcysteine for 3 days is safe and efficacious. collapse abstract

Acute dysautonomia: a rare manifestation of diabetic autonomic neuropathy masquerading as pheochromocytoma.

Accidental provocation of phaeochromocytoma: the forgotten hazard of metoclopramide?

The perilous potential of metoclopramide when used inadvertently in patients harbouring phaeochromocytomas goes largely under-recognised. Despite the rarity of phaeochromocytoma, clinicians should exercise caution in the use of metoclopramide among h... expand abstractypertensives and those with labile blood pressures, given the potentially life-threatening crisis it can readily evoke in those with this tumour. We report a series of three patients with phaeochromocytoma who developed acute crises from metoclopramide. collapse abstract

1-year pulmonary function and health status in survivors of severe acute respiratory syndrome.

STUDY OBJECTIVES: To characterize the long-term pulmonary function and health status in a prospectively identified cohort of patients who survived the severe acute respiratory syndrome (SARS). DESIGN: Prospective follow-up cohort study. SETTING: Univ... expand abstractersity-affiliated hospital. PATIENTS: Ninety-four patients who recovered from SARS were assessed at a uniform time point of 1 year after hospital discharge. MEASUREMENTS: The study included the measurement of static and dynamic lung volumes, the determination of the diffusing capacity of the lung for carbon monoxide (D(LCO)), and a health status evaluation using the St. George Respiratory Questionnaire (SGRQ). RESULTS: Eleven patients (12%) had mild impairment of FVC, 20 (21%) had mild impairment of FEV1, 5 (5%) had mild impairment of the FEV1/FVC ratio, and 17 (18%) had mild impairment of the D(LCO). There was one patient (1%) who had moderate impairment of FVC, one patient (1%) who had moderate impairment of the FEV1/FVC ratio, and three patients (3%) who had moderate impairment of the D(LCO). No pulmonary function abnormalities were detected in 59 patients (63%). Mean scores were significantly higher (ie, worse) than the population norms in the activity (p < 0.001), impacts (p < 0.001), and total (p < 0.001) domains of the SGRQ. CONCLUSIONS: One year after recovery from SARS, persistent pulmonary function impairment was found in about one third of patients. The health status of SARS survivors was also significantly worse compared with the healthy population. The main determinants of morbidity in recovered SARS patients need to be further defined. collapse abstract

Hypocortisolism in survivors of severe acute respiratory syndrome (SARS).

OBJECTIVE: Following the severe acute respiratory syndrome (SARS) outbreak, many survivors were observed to suffer from psychosomatic symptoms reminiscent of various endocrine disorders. Hence, we sought to determine the existence of any chronic endo... expand abstractcrine sequelae in SARS survivors. DESIGN, PATIENTS, MEASUREMENTS: Sixty-one survivors of SARS prospectively recruited were analysed for hormonal derangements 3 months following recovery. Patients with pre-existing endocrine disorders were excluded. Any endocrine abnormalities diagnosed were investigated and treated where indicated up to a year. Serial evaluation facilitated characterization of trends and prognostication of any endocrinological aberrations. RESULTS: Twenty-four (39.3%) patients had evidence of hypocortisolism. The hypothalamic-pituitary-adrenal (HPA) axis dysfunction of the majority resolved within a year. Two (3.3%) of the hypocortisolic cohort had transient subclinical thyrotoxicosis. Four (6.7%) were biochemically hypothyroid, being comprised of three with central hypothyroidism and one with primary hypothyroidism. Two of the three with central hypothyroidism had concomitant central hypocortisolism. Eight had subnormal DHEAS levels. CONCLUSIONS: These preliminary findings highlight a possible aetiologic role of SARS-associated coronavirus in causing a reversible hypophysitis or direct hypothalamic effect, with the HPA axis affected more frequently than the HPT axis. collapse abstract

Under-recognised paradox of neuropathy from rapid glycaemic control.

Insulin induced neuropathy has been reported previously in people with diabetes treated with insulin, and subsequently reported in patients with insulinomas. However, neuropathy caused by rapid glycaemic control in patients with poorly controlled dia... expand abstractbetes with chronic hyperglycaemia is not a widely recognised entity among clinicians worldwide. It is expected that this phenomenon of paradoxical complication of neuropathy in the face of drastic decreases in glycosylated haemoglobin concentrations will assume greater importance with clinicians achieving glycaemic targets at a faster pace than before. collapse abstract

A hypothetical index of hypothalamic-pituitary-adrenal (HPA) axis function.

The short ACTH stimulation test (SST) is commonly used by clinicians to determine the integrity of the hypothalamic-pituitary-adrenal (HPA) axis in cases of suspected adrenal insufficiency. Concern has arisen for under-diagnosis of central hypocortis... expand abstractolism using the standard dose (250 mcg) SST with the recent introduction of low-dose (1 mcg) SST as a potentially more sensitive test for central hypocortisolism. Amidst this uncertainty, I will present a novel index hypothesized to extend the sensitivity of the standard dose SST as an adjunctive diagnostic tool for any level of hypocortisolism. collapse abstract

Pulmonary function and exercise capacity in survivors of severe acute respiratory syndrome.

The aim of this study was to investigate pulmonary function and exercise capacity in a group of survivors of the severe acute respiratory syndrome (SARS). At 3 months after hospital discharge, 46 survivors of SARS underwent the following evaluation: ... expand abstractspirometry, static lung volumes and carbon monoxide transfer factor (TL,CO). In total, 44 of these patients underwent cardiopulmonary exercise testing. No abnormalities were detected in the pulmonary function tests in 23 (50%) of the patients. Abnormalities of forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC and TL,CO were detected in seven (15%), 12 (26%), one (2%) and 18 (39%) patients, respectively. All of these abnormalities were mild except in one case. In 18 patients (41%), the maximum aerobic capacity was below the lower limit of the normal range. Breathing reserve was low in four patients and significant oxygen desaturation was detected in a further four patients. Comparison of the measured exercise capacity with resting pulmonary function tests showed many cases of discordance in impairment. In conclusion, pulmonary function defects were detected in half of the recovered severe acute respiratory syndrome patients 3 months after hospital discharge, but the impairment was mild in almost all cases. Many patients had reduced exercise capacity that cannot be accounted for by impairment of pulmonary function. collapse abstract

Endocrinological aberrations in survivors of the severe acute respiratory syndrome (SARS) in Singapore.