The effect of thyrotoxicosis on adrenocortical reserve

OBJECTIVE: Variations in thyroid function are known to be associated with changes in adrenocortical activity. Previous studies in animals have suggested that long-standing hyperthyroidism may be associated with diminished adrenal functional reserve despite a continuing hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. In humans, there has been no direct assessment of adrenal secretory reserve in clinical thyrotoxicosis. This study aimed to assess adrenocortical reserve in response to low-dose ACTH, following dexamethasone suppression, in patients with severe thyrotoxicosis. DESIGN AND METHODS: Ten patients (four men and six women, 30-45 years) with severe long-standing thyrotoxicosis due to Graves' disease (n=6) or toxic nodular goitre (n=4) were studied at diagnosis and again when in a stable euthyroid state following drug therapy for 8-12 months. All patients underwent ACTH stimulation tests at 0800h with ACTH(1-24) (Cortrosyn; 0.1microg/kg body weight, i.v.) following overnight suppression of the HPA axis with dexamethasone (1mg per os at 2300h). Serum cortisol was assayed at -15, 0, 15, 30, 60 and 90min after the administration of ACTH. RESULTS: The mean (+/-s.d.) peak and delta cortisol responses to ACTH (634.5+/-164nmol/l and 618+/- 196nmol/l respectively), as well as the net area under the response curve (36769+/-12188nmol/lx min) in the hyperthyroid patients were significantly lower compared with the values when the same patients were euthyroid (911+/-157nmol/l, 905+/-160nmol/l and 57652+/-10128nmol/lxmin respectively; P<0.005). Subnormal peak cortisol responses (<500nmol/l) were observed in two severely toxic patients. The findings were independent of the cause of thyrotoxicosis. CONCLUSION: In patients with severe thyrotoxicosis, cortisol secretion in response to low-dose ACTH stimulation, following dexamethasone suppression, is lower in the hyperthyroid than in the euthyroid state. It appears that thyrotoxicosis is associated with subtle impairment of adrenocortical reserve.     

The influence of 24 h urine sampling on the evaluation of renal dysfunction.

Sir, Renal dysfunction and the treatment of renal disease dependon glomerular filtration rate (GFR) and proteinuria (Upr). Currentguidelines recommend the use of creatinine–based estimationequations to predict GFR in patients with chronic kidney disease(CKD) [1]. The accuracy of these equations has been questioned,in patients with altered body composition, in proportion tomuscle mass (i.e. male/female) [2]. Even the proposed estimationof GFR using cystatin C is not independent of body composition[3]. For these reasons, 24 h urinary collection (U_{24 h}     

Children in Sauna: Electrocardiographic Abnormalities

ABSTRACT. We studied changes in ECG in 81 children and 20 adolescents and young adults when they were exposed to heat stress in a climatic chamber, which resembled an ordinary Finnish sauna. Changes were similar to those caused by increased sympathetic activity in 57% of the subjects during the bath and in 23% during the recovery period. Three children had extrasystoles during and four after sauna. One previously healthy 5-year-old girl with wandering pacemaker sacred a 3.3 sec sinus arrest and had reversible junctional rhythm during the heat exposure. We conclude that, although these changes were transient and benign, the sinus arrest suggest that heat stress in sauna is considerable and may be risky for those children who have disorders of the sinoatrial node.     

Excess body weight and risk of first-ever acute ischaemic non-embolic stroke in elderly subjects

In a population-based case–control study we assessed the association between obesity and acute ischaemic/non-embolic stroke. A total of 163 patients aged older than 70 years (88 men and 75 women) admitted due to a first-ever-in-a-lifetime acute ischaemic/non-embolic stroke and 166 volunteers (87 men and 79 women) without a history of cardiovascular disease were included. The association of stroke with body mass index (BMI) or waist circumference (WC) was determined by multivariate logistic regression modelling after adjusting for potential confounding factors. Overweight and obesity were more prevalent amongst stroke patients compared to controls. Subjects with a BMI ≥30 kg/m² had 2.5-times higher odds to suffer an acute ischaemic/non-embolic stroke compared to subjects within the lowest BMI category of 18.5–20.9 kg/m². Analysis of interaction showed that in the presence of overweight and/or obesity (classified as a BMI ≥25 kg/m² and/or a WC >102 cm in men and >88 cm in women) the inverse relationship between HDL cholesterol and ischaemic/non-embolic stroke was negated. Excess weight is associated with an increased risk of acute ischaemic/non-embolic stroke in elderly individuals independently of concurrent metabolic derangements. Moreover, in the presence of obesity, HDL cholesterol loses its protective effect against ischaemic stroke.     

Serological Evidence for the Role of Bacterial Infections in the Pathogenesis of Thyroid Diseases

ABSTRACT. Subacute thyroiditis is generally believed to be of viral origin, and infection is also suspected of playing a role as a triggering factor in the pathogenesis of autoimmune thyroid diseases. We have measured a broad spectrum of bacterial and viral antibodies in paired sera of 32 patients with thyroid disease of recent onset. The data indicate a preceding infection in 14 (44%) of the patients, enterobacterial in 5, streptococcal in 4 and staphylococcal in 2. A viral infection was suggested in 6 patients, in each case caused by different agents; 3 of them also showed evidence of a bacterial infection. Patients with positive microbial serology were found in all diagnostic groups, including subacute thyroiditis, Graves' disease and Hashimoto's disease. These results suggest an association between a preceding bacterial infection and the development of thyroid disease in some patients.     

Postappendectomy fluid collections in children: incidence, nature, and evolution evaluated using US

At the authors' medical center, most patients with postappendectomy fluid collections are treated conservatively. Thirty-two (15%) of 216 children underwent postoperative sonography following appendectomies. In ten patients (31%), a total of 16 fluid collections were found on the initial postoperative sonogram. In the seven patients (70%) whose fluid collections were confined to the pelvis, the condition was treated conservatively and it resolved in 2-9 weeks. In three patients, fluid collections required surgical drainage and proved to be abscesses. In two of the three patients, abscesses were multiple and widely distributed in the abdomen, and the patients were clinically ill. The authors conclude that clinically symptomatic fluid collections develop postoperatively in approximately 5% of children who have undergone appendectomy for acute appendicitis and that the size and course of the fluid collection can be objectively monitored using sonography. Such fluid collections confined to the pelvis ultimately resolve with conservative, nonoperative therapy, although resolution may take up to 2 months.     

Maternal and paternal alcohol consumption and miscarriage

Summary. To explore the role of parental alcohol consumption in miscarriage we interviewed 80 women who miscarried about their own and their partners' drinking habits. A control group of 81 gestational-age-matched women whose pregnancy ended in the delivery of a healthy infant at term were similarly questioned. The use of alcohol by women and men was equally frequent in both groups. Before pregnancy, the mean alcohol consumption per week had been about 1–2 drinks for the women and 4–5 drinks for the men. During the presumed day of conception, 13% of the women who miscarried and 11% of the women in the control group had drunk on average 3–4 drinks; the other women had been abstinent at this time. Of the partners, 13% and 15%, respectively, had taken a mean of 4–5 drinks. In both groups 58% of the subjects continued to consume alcohol during pregnancy. The mean consumption was about one drink a week by the women who miscarried and half a drink a week in the control group. Of women who miscarried, 36 had a blighted ovum and in this subgroup alcohol consumption in both women and men was similar to that in the other women who miscarried and their partners, suggesting that alcohol is not causally related to the development of a blighted ovum. These results suggest that moderate maternal or paternal alcohol consumption does not increase the risk of miscarriage.