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T Cundy

Publications and source records attributed to T Cundy.

At least 73 records · Page 4Linked to original sources
PubMed1993

Reversibility of hypogonadotrophic hypogonadism associated with genetic haemochromatosis.

OBJECTIVE: Recent reports have suggested that hypogonadotrophic hypogonadism in men with genetic haemochromatosis can be reversed by aggressive venesection therapy. We have studied prospectively men with this complication of haemochromatosis in order to document the frequency and completeness of recovery from hypogonadism. PATIENTS AND DESIGN: Six men with symptomatic hypogonadotrophic hypogonadism and genetic haemochromatosis were studied before beginning venesection therapy and again after depletion of body iron stores. MEASUREMENT: Symptoms of hypogonadism, serum gonadotrophins and serum total and free testosterone concentrations. RESULTS: Five men aged 47-66 showed no symptomatic improvement and no change in serum gonadotrophin or testosterone concentrations. The symptoms of one man, aged 33, resolved completely after venesection and this was accompanied by increases in serum LH and FSH. Serum total and free testosterone concentrations increased fourfold, but remained subnormal. CONCLUSION: Only one partial recovery from hypogonadotrophic hypogonadism was seen and this was in the youngest subject. In reviewing the other documented cases of reversal it would appear that the age at diagnosis is critical and there are no proven cases of reversal of hypogonadotrophic hypogonadism in men over the age of 40 at the start of venesection therapy.

Aged↗
PubMed1993

Determinants of birth-weight in women with established and gestational diabetes.

Increased birth-weight (macrosomia) can complicate the diabetic pregnancy, but many factors other than hyperglycaemia can influence birth-weight, in particular maternal obesity. In a mixed population (European, Maori and Pacific Islander) with a high prevalence of glucose intolerance and obesity we have examined the relative impact of various maternal factors on birth-weight in women with both established and gestational diabetes. Mean birth-weight was significantly greater in women with established or gestational diabetes than in controls (p < 0.0001), but was similar in women with gestational and established diabetes, despite glycaemic control being significantly poorer (p < 0.0001) in the latter. Birth-weight closely paralleled prepregnancy body mass index rather than glycaemic control, but in Maori women it was lower than expected, probably because of their high prevalence of smoking. Daily cigarette consumption was negatively correlated with birth-weight (p < 0.01) despite the smokers having significantly poorer glycaemic control (p < 0.001). The most significant variables influencing birth-weight in the diabetic pregnancy were gestational age at delivery, prepregnancy body mass index, maternal height, estimated weight gain during pregnancy, the presence of hypertension and cigarette smoking (the latter 2 having negative effects on birth-weight). Glycaemic control in the last half of pregnancy was not significant in this analysis. We conclude that within the limits of glycaemic control which we obtained, birth-weight was largely determined by maternal factors other than hyperglycaemia. Birth-weight thus has severe limitations as an outcome measure of the diabetic pregnancy.

Adult↗
PubMed1991

Bone density in women receiving depot medroxyprogesterone acetate for contraception.

OBJECTIVE: To determine if the use of the injectable contraceptive depot medroxyprogesterone (DMPA), which reduces ovarian oestrogen production, is associated with changes in bone density. DESIGN: Population study. DMPA users were compared with two control groups selected from larger population studies and individually matched for several putative determinants of bone density (age, race, body mass index, and years of oestrogen deficiency). Controls and DMPA users were matched without prior knowledge of their bone density measurements. SETTING: Teaching hospital and community family planning clinics. SUBJECTS: 30 current users of DMPA with a minimum five years' previous use, 30 premenopausal controls, and 30 postmenopausal controls. MAIN OUTCOME MEASURE: Lumbar spine and femoral neck bone mineral density assessed by dual energy x ray absorptiometry. RESULTS: Compared with premenopausal controls matched for age, race, and body mass index, DMPA users had significantly reduced bone density in the lumbar spine (mean difference 7.5% (95% confidence interval 1.9% to 13.1%), p = 0.002) and in the femoral neck (6.6%, (0.8% to 12.3%), p = 0.007). Compared with postmenopausal controls matched for body mass index and duration of oestrogen deficiency, DMPA users had greater bone density in the lumbar spine (8.9% (4.3% to 13.5%), p = 0.001), but in the femoral neck the difference in bone density was less (4.0% (-0.4% to 8.5%), p = 0.04). CONCLUSIONS: Women using DMPA have bone density values intermediate between those of normal premenopausal and postmenopausal controls; thus, the degree of oestrogen deficiency induced by DMPA may have an adverse effect on bone density.

Absorptiometry, Photon↗
PubMed1989

Marxism today.

Explore the source record for details and available documents.

Albuterol↗
PubMed1989

Hypogonadism and sexual dysfunction in hemochromatosis: the effects of cirrhosis and diabetes.

The contribution of diabetes and cirrhosis to sexual dysfunction and hypogonadism was evaluated by two-way analysis of variance in a group of 30 men with idiopathic hemochromatosis. The prevalence of severe sexual dysfunction was significantly higher in men with hemochromatosis than in a control group matched for prevalence of diabetes and age (P less than 0.001). In both controls and hemochromatosis patients the presence of diabetes was significantly associated with sexual dysfunction (P less than 0.005), but the more severe symptoms in the hemochromatosis patients were related to the additive effects of hypoandrogenism (P less than 0.01). Sexual dysfunction was a common early complaint in hemochromatosis patients, but these symptoms were frequently overlooked, leading to diagnostic delay. Mean testicular volume was a useful measure of gonadal status, being significantly correlated with indices of serum free testosterone (rs = 0.83; P less than 0.01) and LH (rs = 0.71; P less than 0.001). The presence of cirrhosis did not contribute significantly to symptomatology, but had an effect independent of and additive to hypogonadotropic hypogonadism in reducing serum free testosterone (P less than 0.02) and estradiol (P less than 0.002), an effect apparently mediated through central rather than testicular mechanisms. Hypoandrogenism was associated with an increase in serum sex hormone-binding globulin (SHBG) concentrations (P less than 0.005), but cirrhosis also had an independent effect in raising SHBG (P less than 0.005), which could not be accounted for by changes in circulating sex hormone concentrations. Thus, the evaluation of sexual dysfunction or hypogonadism in men with hemochromatosis requires consideration of the effects of both diabetes and cirrhosis. Because of the greater variance in SHBG some estimate of free testosterone rather than total testosterone is preferable.

Adult↗
PubMed1989

Increased activated T-lymphocytes and normal thyrotropin receptor antibody levels in Graves' disease in long-term remission.

The involvement of the immune system in the attainment and maintenance of carbimazole-induced remission in Graves' disease is poorly understood. We have investigated levels of T-lymphocytes expressing the HLA DR marker of activation and levels of thyrotropin receptor antibody (TRAb) in patients in sustained, carbimazole-induced, long-term remission from Graves' disease (median duration of remission 29 months, range 7-64). Levels of activated T-lymphocytes were increased in patients with long-term remission compared with controls (p less than 0.05) and were no different from the high levels found in patients with active Graves' disease. In contrast, levels of TRAb were normal in patients in long-term remission but high in patients with active disease (p less than 0.01). These results show that increased activated T-lymphocytes but normal levels of antibody to the thyrotropin receptor characterize patients in carbimazole-induced long-term remission of Graves' disease suggesting that activated T-lymphocytes may be important in the maintenance of remission.

Adult↗
PubMed1987

Rapid suppression of plasma alkaline phosphatase activity after renal transplantation in patients with osteodystrophy.

Plasma alkaline phosphate activity is a important marker of increased skeletal turnover (both resorption and formation) and bone disease in uraemia, but its value after renal transplantation is uncertain. The rate of fall of alkaline phosphatase was compared in three groups of uraemic patients with osteodystrophy and elevated serum alkaline phosphatase undergoing either renal transplantation, parathyroidectomy or therapy with 1a hydroxylated vitamin D derivates. Alkaline phosphatase fell after transplantation, irrespective of graft function, with a half-time significantly less than the other treatments (p less than 0.001). We suggest that this represents a direct inhibitory effect of steroids on osteoblasts and that alkaline phosphatase is thus an unreliable marker of bone resorption after transplantation.

Alkaline Phosphatase↗
PubMed1987

Osteopenia in systemic mastocytosis: natural history and responses to treatment with inhibitors of bone resorption.

Studies of a 63-year-old woman with osteopenia due to systemic mastocytosis are reported. Delay in making the diagnosis and the occurrence of coincident medical problems meant that radiographs during a 12-year period were available for study. Skeletal symptoms began 20 years after the skin lesions of mastocytosis first appeared, but once established bone loss was rapid, particularly from cortical bone (estimated at 3.75% pa). Biochemical and histological measurements indicated a "high turnover" bone disease and treatment with inhibitors of bone resorption was assessed. Oral, but not intravenous, clodronate was effective in reducing bone turnover as judged by falls in hydroxyproline excretion (p less than 0.01) and serum alkaline phosphatase (p less than 0.01). Mithramycin and chlorambucil were ineffective. Clodronate may be beneficial in arresting bone loss in this disorder.

Biopsy↗
PubMed1987

Remission of hypoparathyroidism during lactation: evidence for a physiological role for prolactin in the regulation of vitamin D metabolism.

We studied a young woman with surgical hypoparathyroidism who, on her usual maintenance dose of calcitriol, developed hypercalcaemia 9 d postpartum when lactation was established. Serum values of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) values were very high (127 pg/ml). The patient remained without exogenous calcitriol treatment for 40 d, during which time serum 1,25(OH)2D3 levels remained within the normal range and serum calcium fell with a half-time of 27 d. The requirements for calcitriol increased to antepartum levels when lactation had ceased. There was a close negative correlation between requirements for calcitriol and serum PRL values. After weaning, an episode of hypercalcaemia was induced by increasing the dose of calcitriol. On stopping calcitriol the serum 1,25(OH)2D3 fell to low values (4 pg/ml) within 2 d and serum calcium fell with a half-time of 3 d, necessitating the early reintroduction of calcitriol. We conclude that in hypoparathyroidism exogenous vitamin D requirements fall during lactation because of enhanced endogenous production of 1,25(OH)2D3. The lactation-associated increase in circulating 1,25(OH)2D3 concentrations thus results from a parathyroid hormone-independent mechanism, possibly by an effect of PRL on the 1 alpha-hydroxylase.

Adult↗
PubMed1987

Serum thyrotrophin in patients with destructive pituitary lesions assessed by a sensitive immunoradiometric assay.

Using a sensitive immunoradiometric assay, serum concentrations of thyrotrophin (TSH) were measured both basally and after intravenous thyrotrophin releasing hormone (TRH) in two groups of patients with destructive pituitary lesions. Group A patients, who had more extensive pituitary hormone deficiencies and biochemical evidence of hypothyroidism at the time of study, had significantly lower mean serum TSH concentrations than the group B patients who were biochemically euthyroid. Basal TSH was below the lowest value seen in a control group of normal subjects in 5 of the 8 group A patients. In all patients TSH increased significantly after injection of TRH; the peak values being significantly correlated with the basal. In contrast to recent studies, which have emphasised other mechanisms in the production of secondary hypothyroidism, our data suggest that inadequate production of immunoassayable TSH is a common cause of secondary hypothyroidism in patients with destructive pituitary disease. Little, if any, additional clinical information is to be gained by measurement of TSH after TRH stimulation in this circumstance.

Adolescent↗
PubMed1986

Pathogenesis of osteomalacia in chronic renal failure and its relationship to vitamin D.

Considerable confusion arises in defining osteomalacia in the presence of renal disease. There are no radiographic or biochemical features which satisfactorily identify all patients with osteomalacia. Histological definitions need to distinguish increased amounts of osteoid due to defective mineralisation from that due to increased bone turnover, both of which may coexist in chronic renal failure. The pathogenesis of osteomalacia in renal failure is multifactorial and not always due to defective metabolism of vitamin D. Deficient production of 25-hydroxyvitamin D may occur because of nutritional privation or urinary losses in the nephrotic syndrome, but these are rare causes of osteomalacia in patients on haemodialysis treatment. It is not clear to what extent defective production of calcitriol, characteristic of end-stage chronic renal failure is causally related to osteomalacia, in part due to uncertainties as to whether vitamin D acts directly on bone to promote mineralisation or whether its effects are mediated indirectly by modulating calcium and phosphate transport at other sites. Following the institution of renal replacement therapy, the incidence of osteomalacia varies markedly between renal units due to the skeletal retention of aluminium caused by the contamination of dialysis fluid or by the chronic ingestion of aluminium-containing phosphate binding agents. This form of osteomalacia is associated with a high risk of fracture, probably more related to depressed bone formation than to the presence of osteomalacia. Rarer causes of osteomalacia include parathyroidectomy and calcium and phosphate deficiency.

Aluminum↗
PubMed1986

Comparative effects of alfacalcidol and parathyroidectomy with vitamin D in hyperparathyroid renal bone disease.

Parathyroidectomy is now rarely undertaken for hyperparathyroid bone disease in chronic uraemia unless treatment with 1 alpha-hydroxylated vitamin D3 derivatives is unsuccessful. However, no comparisons have been reported of the use of parathyroidectomy with 1 alpha-hydroxylated vitamin D3 derivatives in patients with bone disease of comparative severity. We studied 14 uraemic patients on maintenance haemodialysis treatment before and after treatment with 1 alpha-hydroxyvitamin D3 (alfacalcidol) and compared the findings with those from 12 patients studied before and after parathyroidectomy followed by treatment with vitamin D. The initial severity of the bone disease in the two groups was similar as judged by biochemical, radiographic and histological findings. Both groups demonstrated significant falls in plasma alkaline phosphatase (p less than 0.005) and healing of radiographic erosions after treatment. The histological changes in bone, however, were more marked in patients after parathyroidectomy. Significant reductions were observed in the active osteoblastic surface (p less than 0.005), the total resorption surface (p less than 0.05), the active resorption surface (p less than 0.02) and the index of marrow fibrosis (p less than 0.001), but these indices did not change significantly in the alfacalcidol-treated patients. We concluded that the responses to alfacalcidol in bone are less complete than those obtained with parathyroidectomy despite similar biochemical and radiographic responses.

Adolescent↗
PubMed1985

Who gets renal bone disease before beginning dialysis?

To identify patients at risk from renal bone disease we compared the demographic characteristics of 243 patients with end stage renal failure grouped according to the presence (97 (40%] or absence of severe renal bone disease as judged by histological criteria. Youth, female sex, tubulointerstitial types of nephropathy, and a long duration of uraemia were all identified as significant independent risk factors for the development of bone disease. The relative risks from being female and having tubulointerstitial renal disease were separately identifiable when the estimated observation of renal failure was short (less than four years). The identification of patients at high risk from bone disease may clarify the pathogenesis and treatment strategies of renal osteodystrophy.

Adolescent↗