Nocturnal enuresis—theoretic background and practical guidelines

Nocturnal polyuria, nocturnal detrusor overactivity and high arousal thresholds are central in the pathogenesis of enuresis. An underlying mechanism on the brainstem level is probably common to these mechanisms. Enuretic children have an increased risk for psychosocial comorbidity. The primary evaluation of the enuretic child is usually straightforward, with no radiology or invasive procedures required, and can be carried out by any adequately educated nurse or physician. The first-line treatment, once the few cases with underlying disorders, such as diabetes, kidney disease or urogenital malformations, have been ruled out, is the enuresis alarm, which has a definite curative potential but requires much work and motivation. For families not able to comply with the alarm, desmopressin should be the treatment of choice. In therapy-resistant cases, occult constipation needs to be ruled out, and then anticholinergic treatment—often combined with desmopressin—can be tried. In situations when all other treatments have failed, imipramine treatment is warranted, provided the cardiac risks are taken into account

Common endocrine and metabolic disorders among the Chinese in Hong Kong

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High-density lipoprotein cholesterol, hepatic lipase and lipoprotein lipase activities in thyroid dysfunction - Effects of treatment

The have investigated the effects of hyper- and hypothyroidism (clinical and subclinical) on lipid metabolism, with special emphasis on serum high-density lipoprotein cholesterol, post-heparin plasma hepatic lipase and lipoprotein lipase activities. In 16 patients with hyperthyroidism, increased post-heparin plasma hepatic lipase activity, decreased serum total cholesterol and serum high-density lipoprotein cholesterol were found while lipoprotein lipase activity and serum triglyceride were normal. In six patients with overt hypothyroidism serum total cholesterol and triglyceride were increased, post-heparin plasma hepatic lipase and lipoprotein lipase were decreased while serum high-density lipoprotein cholesterol was normal. In six patients with subclinical hypothyroidism, serum total cholesterol was increased, serum high-density lipoprotein cholesterol was decreased was decreased, while serum triglyceride, post-heparin plasma hepatic lipase and lipoprotein lipase were normal. When the three groups of patients became euthyroid, serum total cholesterol, serum triglyceride, post-heparin plasma hepatic lipase, lipoprotein lipase, and serum high-density lipoprotein cholesterol reverted to normal except for serum high-density lipoprotein cholesterol in the hyperthyroid group which showed no significant change with treatment. A positive correlation was found between serum T3 and post-heparin plasma hepatic lipase while negative correlations were found between serum total cholesterol and serum T3, post-heparin plasma hepatic lipase and serum total cholesterol, lipoprotein lipase and serum triglyceride respectively. Thus in these patients with thyroid dysfunction, significant reversible alterations in serum total cholesterol, triglyceride and high-density lipoprotein cholesterol were found and could be correlated with the observed changes in the activities of hepatic lipase and lipoprotein lipase.link_to_subscribed_fulltex

Effects of heroin addiction on thyrotrophin, thyroid hormones and prolactin secretion in men

Pituitary-thyroid function in male heroin addicts and addicts after abstinence (ex-addicts) was studied and compared with that of healthy euthyroid men. In heroin addicts the increases in circulating total thyroxine and triiodothyronine levels were accompanied by an increase in the thyroid hormone uptake test. These changes may reflect a quantitative increase in thyroxine binding globulin. Reverse triidothyronine concentrations in heroin addicts were normal. The thyrotrophin-releasing hormone elicited a diminished thyrotrophin response in heroin addicts which was significantly different from that in control subjects and ex-addicts. An elevation of serum prolactin was noted in heroin addicts, while ex-addicts had normal levels. Gradual recovery of pituitary-thyroid function occurred after heroin withdrawal.link_to_subscribed_fulltex

Pituitary-thyroid responses to surgical stress

The effect of surgery on pituitary-thyroid function was studied in 1 euthyroid patients. There was a sharp early increase in total thyroxine level, causing displacement of triiodothyronine from thyroid hormone binding proteins resulting in the elevation of the biologically more potent free triiodothyronine fraction. The serum triiodothyronine concentration fell rapidly during and after the operation, with a concomitant rise in reverse triiodothyronine level. Increased prolactin levels were found during and after surgery. With no post-operative complication, recovery of normal pituitary-thyroid function occurred after 4 to 7 days of convalescence.link_to_subscribed_fulltex

Effect of surgical stress on pituitary-testicular function

The effect of surgical stress on the secretions of LH, FSH, testosterone (T) and oestradiol (E2) were studied in twelve male patients. During surgery LH rose significantly; post-operatively, LH fell but remained persistently elevated a week after operation. However, T and E2 fell progressively to a nadir on the second and fifth post-operative day respectively and remained suppressed. Serum FSH showed no significant change. Despite a post-operative decrease in sex hormone binding globulin (SHBG) binding capacity, non-SHBG bound T showed a decrease parallel to T. Multiple sampling studies showed that the secretions of LH were increased and that of T were decreased post-operatively. Following surgery, LH responses to LHRH were magnified, FSH and T responses showed no significant change when compared with the pre-operative responses. These data suggest that secretions of LH were increased during surgery. Following surgical stress, T and E2 concentrations were suppressed resulting in a compensatory elevation of LH concentrations.link_to_subscribed_fulltex

The effect of heroin addiction on pituitary-testicular function

The effect of heroin addiction on pituitary-testicular function was studied in 54 active and 19 abstinent addicts and their results were compared with those of 43 age-matched controls. Abnormal sexual function was frequently found in heroin addicts and this persisted after drug withdrawal. The mean total (mean ± SE, 18.1 ± 1.0 nmol/l) and free (0.17 ± 0.03 nmol/l) testosterone (T) levels in heroin addicts were significantly lower than those in healthy controls (total T 22.8 ± 1.1 nmol/l, P<0.005; free T 0.30 ± 0.03 nmol/l, P<0.005). The mean sex hormone binding globulin binding capacity was higher in heroin addicts (60.1 ± 5.2 nM) than in healthy controls (35.5 ± 2.1 nM). These hormonal changes returned promptly to normal after withdrawal. The basal LH and FSH and the responses to LHRH were comparable in the 3 groups studied. The finding of significantly lower total and free T together with higher SHBG indicates an abnormal testicular function in heroin addiction. Normal basal and LHRH-stimulated LH and FSH levels suggest that chronic heroin abuse depressed testicular function via the hypothalamus or higher centers.link_to_subscribed_fulltex

Dissociated thyroxine, triiodothyronine and reverse triiodothyronine levels in patients with familial goiter due to iodide organification defects

The thyroid function of patients with three different types of organification defect was studied. All patients were characterized by a high thyroidal 131I uptake and a positive perchlorate discharge. Patients with Pendred's syndrome who had goitre and congenital nerve deafness were mostly euthyroid with normal circulating thyroid hormone levels. Only two of them had compensated euthyroidism with elevated total T3, high basal TSH and delayed return to basal value after TRH. The patients who were euthyroid with large goitres and normal hearing had elevated total T3 and an exaggerated TSH response to TRH. The thyroid function of these two groups of patients contrasted with that of goitrous cretins, who were clinically hypothyroid with low circulating total T4, increased T3 and decreased rT3 levels. The data suggest that in patients with intrathyroidal iodine deficiency secondary to organification defect, there is preferential T3 production in an effort to maintain euthyroid state, and this is further substantiated in the case of gross thyroid insufficiency either by enhanced peripheral conversion of T4 to T3, or reduced metabolic clearance of T3 and increased clearance of rT3, resulting in elevated T3 and decreased rT3 levels.link_to_subscribed_fulltex

Hypothalamic hypopituitarism following cranial irradiation for nasopharyngeal carcinoma

Eight patients, one male and seven females, with no pre-existing hypothalamic-pituitary disease, who developed symptoms of hypopituitarism following cranial irradiation for nasopharyngeal carcinoma were studied 5 years or more after radiotherapy. All were GH deficient. Four of the patients with no GH response during insulin tolerance tests (ITT) showed increased GH in response to synthetic human growth hormone releasing factor (GFR-44). Four patients had impaired cortisol responses to ITT, and gradual but diminished cortisol responses to ovine corticotrophin releasing factor (CRF-41). There was no significant difference between mean peak increments in response to ITT and those in response to CRF-41. TSH responses to TRH were delayed in five and absent in two patients; four of these had low free T4 index. Prolactin was raised in all seven women and increased further in response to TRH. Two patients had impaired gonadotrophin responses to LHRH. None of the patients had clinical or biochemical evidence of diabetes insipidus. These data suggest that postirradiation hypopituitarism in these patients results from radiation damage to the hypothalamus leading to varying degrees of deficiency of the hypothalamic releasing or inhibitory factors.link_to_subscribed_fulltex