Pituitary responsiveness to GH-releasing hormone, GH-releasing peptide-2 and thyrotrophin-releasing hormone in critical illness

OBJECTIVE Protein hypercatabolism and preservation of fat depots are hallmarks of critical illness, which is associated with blunted pulsatile GH secretion and low circulating IGF-I, TSH, T4 and T3. Repetitive TRH administration is known to reactivate the pituitary-thyroid axis and to evoke paradoxical GH release in critical illness. We further explored the hypothalamic-pituitary function in critical illness by examining the effects of GH-releasing hormone (GHRH) and/or GH-releasing peptide-2 (GHRP-2) and TRH administration. PATIENTS AND DESIGN Critically ill adults (n=40; mean age 55 years) received two i.v. boluses with a 6-hour interval (0900 and 1500 h) within a cross-over design. Patients were randomized to receive consecutively placebo and GHRP-2 (n=10), GHRH and GHRP-2 (n=10), GHRP-2 and GHRH+GHRP-2 (n=10), GHRH+GHRP-2 and GHRH+GHRP-2+TRH (n=10). The GHRH and GHRP-2 doses were 1μg/kg and the TRH dose was 200μg. Blood samples were obtained before and 20, 40, 60 and 120 minutes after each injection. MEASUREMENTS Serum concentrations of GH, T4, T3, rT3, thyroid hormone binding globulin (TBG), IGF-I, insulin and cortisol were measured by RIA; PRL and TSH concentrations were determined by IRMA. RESULTS Critically ill patients presented a striking GH response to GHRP-2 (mean±SEM peak GH 51±9 μg/l in older patients and 102±2μg/l in younger patients; P=0.005 vs placebo). The mean GH response to GHRP-2 was more than fourfold higher than to GHRH (P=0.007). In turn, the mean GH response to GHRH+GHRP-2 was 2.5-fold higher than to GHRP-2 alone (P=0.01), indicating synergism. Adding TRH to the GHRH+GHRP-2 combination slightly blunted this mean response by 18% (P=0.01). GHRP-2 had no effect on serum TSH concentrations whereas both GHRH and GHRH+GHRP-2 evoked an increase in peak TSH levels of 53 and 32% respectively. The addition of TRH further increased this TSH response < ninefold (P=0.005), elicited a 60% rise in serum T3 (P=0.01) and an 18% increase in T4 (P=0.005) levels, without altering rT3 or TBG levels. GHRH and/or GHRP-2 induced a small increase in serum PRL levels. The addition of TRH magnified the PRL response 2.4-fold (P=0.007). GHRP-2 increased basal serum cortisol levels (531±29nmol/l) by 35% (P=0.02); GHRH provoked no additional response, but adding TRH further increased the cortisol response by 20% (P=0.05). CONCLUSIONS The specific character of hypothalamic-pituitary function in critical illness is herewith extended to the responsiveness to GHRH and/or GHRP-2 and TRH. The observation of striking bursts of GH secretion elicited by GHRP-2 and particularly by GHRH+GHRP-2 in patients with low spontaneous GH peaks opens the possibility of therapeutic perspectives for GH secretagogues in critical care medicine.     

Laparoscopic hysterectomy

Summary Thirty-three patients were selected for laparoscopic hysterectomy and operated on in the Department of Obstetrics, Gynecology and Reproductive Medicine of Clermont-Ferrand University Hospital. Surgical techniques included blunt dissection with scissors and bipolar coagulation to achieve hemostasis. A case was considered successful when all the uterine vessels were treated by laparoscopy. Twenty-four cases were completed laparoscopically (72.7%). None of these patients had postoperative bleeding; 22 had an uneventful postoperative recovery. Nine procedures were converted to laparotomy (27.3%), five because of a difficult or unsatisfactory hemostasis. We conclude that in selected cases, a total hysterectomy can be performed safely by experienced laparoscopists. Further technological progress is necessary to make this procedure more acceptable. Its value as compared to the others will have to be demonstrated.     

Marchiafava-Bignami Disease

Marchiafava-Bignami disease is a rare demyelinating disease involving the corpus callosum and other central white matter tracts. In the patient described here, the disease produced extensive demyelination of the corpus callosum and deep cerebral white matter. This widespread demyelination, confirmed pathologically, was associated with a fulminant fatal course. The magnetic resonance imaging appearance is quite suggestive of Marchiafava-Bignami disease and plays an important role in the premortem diagnosis.     

Human infestation with bird mites in Wollongong.

This is a report of a case of bird mite infestation which occurred in Wollongong in mid-December 1996. The individual suffered hundreds of bites, most of which were marked by itchy red papules 3-4 mm in diameter. Tiny mobile parasites (< 1 mm) collected from the skin and adjacent bedroom wall were identified as bird mites from the family Gamasidae, most probably from the genus Ornithonyssus. The source of the infestation was a starling nest under the eaves adjacent to the bedroom. The report summarises the ways bird mite bites can be distinguished from other insect and arachnid bites. If bird mite infestation is not correctly diagnosed, families who attempt to repeatedly treat it as if it were lice or scabies may incur considerable expense until the source of infestation is eliminated.     

The ethics and conduct of cross-cultural research in developing countries

Bioethics is the study of moral problems as they relate to health-care delivery. The Hippocratic Oath laid the foundation of medical ethics as we know it today. Advances in medical technology have moved attention away from traditional ethical concepts, which are now either taken for granted or have been accorded the back seat. Contemporary ethical issues that occupy the minds of ethicists include euthanasia, advance directives, in vitro fertilization, surrogate motherhood and transplantation. Some of these are of less concern in developing countries than in the developed world. In developing countries, the ethics of cross-cultural research, the ethics of scarcity and sacrifice, and the activities and ethics of multinational companies assume far greater importance. This discussion will concentrate on the ethics and conduct of cross-cultural research in developing countries. The other important topics of scarcity, sacrifice and multinational activity will be covered elsewhere. Culture is the integrated patterns of human knowledge, beliefs and behaviour of a given community. Culture provides individuals with their identity. To work effectively with people it is necessary to view the world from their perspective. This is particularly important when dealing with people from cultures different from one's own. The world is functionally shrinking and there is interdependence not only in the traditional areas of communication and information transfer but also in the economic, environmental, demographic and migration areas. The concept of ‘global health village’ has now become a reality. In the past, researchers seem to have been motivated to conduct studies in developing countries for a variety of reasons. Whereas some of these are laudable, others are of more dubious ethical implications. This article focuses on issues related to the structural design, process and outcome of such research. Anyone contemplating conducting research in developing countries, especially cross-cultural research, must keep three main points in mind. In particular, the collective wisdom of both foreign and local investigators should be pooled to determine the appropriate research question(s) relevant to the needs of the target population. If human subjects are required for the study, ethical obligations based on the principle of respect for the person and respect for the autonomy of study subject must prevail. Finally constant checks and balances must be in place to ensure benefit of the research, not only to science and society but to individual subjects as well.     

Prevalence of mental illness and its impact on the use of home care and nursing homes: a population-based study of older adults in Manitoba.

OBJECTIVES: To determine the prevalence of mental illness in older adults and its effect on home care and personal care home (PCH) use. METHODS: Using nonidentifying administrative records (fiscal years 1997-1998 to 2001-2002) from the Population Health Research Data Repository housed at the Manitoba Centre for Health Policy, we determined the 5-year period prevalence for individuals aged 55 years and over (119 539 men and 145 752 women) for 3 mental illness categories: cumulative mental disorders (those having a diagnosis of depression, anxiety disorder, personality disorder, schizophrenia, and [or] substance abuse), any mental illness, and dementia. We calculated age-specific and age-adjusted rates of home care and PCH use and the prevalence of mental illness in PCH residents. RESULTS: From the group aged 55 to 59 years to the group aged 90 years or older, the prevalence of mental illness increased with the population's age. The prevalence of any mental illness rose from 32.4% to 45.0% in men and from 42.6% to 51.9% in women, and dementia prevalence rose from 2.0% to 33.6% in men and from 1.3% to 40.3% in women. The age-adjusted annual rates of open home care cases per 1000 population aged 55 and older varied by mental illness grouping (no mental disorder, 57 for men and 91 for women; cumulative mental disorders, 162 for men and 191 for women; dementia, 300 for men and 338 for women). The age-adjusted rates of PCH use per 1000 population aged 75 years and older also varied by mental illness grouping (no mental disorder, 53 for men and 78 for women; cumulative mental disorders, 305 for men and 373 for women; dementia, 542 for men and 669 for women). Among patients admitted to (or resident in) a PCH in 2002-2003, 74.6% (87.1%) had a mental illness, and 46.0% (69.0%) had dementia. CONCLUSIONS: Mental illness affects the use of home care and nursing homes profoundly. Individuals with dementia used home care at 3 times the rate of those having no mental illness diagnosis, and they used PCHs at 8 times the rate.     

Depression symptoms in movement disorders: comparing Parkinson's disease, dystonia, and essential tremor.

Depression is common in Parkinson's disease (PD) and affects 30 to 50% of all patients. In contrast to the wealth of research on depression in PD, little is known about the occurrence of depression in other movement disorders. The primary objective of the current study was to determine whether the high prevalence of depression symptoms seen in PD is also found in other movement disorders, by directly comparing rates of specific depression symptoms and depression severity across PD, dystonia, and essential tremor (ET). Three hundred and fifty-four patients with PD, 83 patients with dystonia, and 53 patients with ET completed the Beck Depression Inventory (BDI). We found no significant between-groups differences for depression severity, frequency, or endorsement of specific depression symptoms. Forty-eight percent of PD patients, 37.3% of dystonia patients, and 34% of ET patients were found to be at least mildly depressed (BDI score of 10 or higher). The most commonly endorsed symptoms were fatigability, difficulty with work, anhedonia, and sleep disturbance. Clinicians should be aware that depression is a frequent problem in dystonia and ET, in addition to PD, and inquire about depression symptoms in these patients so that they can be appropriately treated.