Myositis associated with growth hormone therapy

Increased liver enzymes and hormonal therapies in girls and adolescents with Turner syndrome

Elevated liver enzymes can be seen relatively frequently in patients with Turner syndrome (TS), while the pathogenesis of this remains unclear. Our epidemiological and prospective study aimed to investigate: a) the natural 2-yr course of liver disease in a selected cohort of young patients with TS, who had been preliminarily recruited on the basis of persistently elevated liver enzymes; b) the role of prolonged hormonal therapies in the etiology of liver dysfunction. From an overall population of 214 TS patients younger than 20 yr, only 19 (8.9%) were recruited, according to the following inclusion criteria: increased serum concentrations of one or more liver enzymes, exceeding the uppermost limit of the respective normal ranges, and persistence of these liver alterations for 6 months after the preliminary assessment. On the basis of the results of this prospective study, we can conclude that: a) the prevalence of liver abnormalities in girls and adolescents with TS is much lower and more strictly related to hormonal therapies than in TS adults; b) both autoimmunity and obesity are not frequently involved in the etiology of TS liver dysfunction; c) liver damage is either mild or moderate and its severity is not conditioned by karyotype; d) its course may be self-limiting; e) its natural history may be characterized in some cases by a slight deterioration of intrahepatic cholestasis, with no negative repercussions on liver synthetic function.

Genetic and environmental risk factors for idiopathic inflammatory myopathies

Although the studies discussed are beginning to reveal a number of genetic and possible environmental risk factors for myositis, further investigations are needed to fully understand and classify these syndromes. The difficulties in this process include small numbers of subjects with varying disease phenotypes available for study, polygenic risk factors for which it remains unclear which are primary and which are secondary or linked genes, and the lack of validated environmental exposure assessment tools. New technologies and international collaborative approaches, however, may overcome some of these difficulties and allow us to identify genetic and environmental risk factors, as well as the critical gene-environment interactions in the IIM and its subgroups. Nonetheless, our understanding of these diseases is still in the early stages. Although we have learned a great deal about these disorders through detailed investigations over the last several decades, we have even further to go to understand the environmental triggers and genetic susceptibilities for the myositis syndromes.

Juvenile dermatomyositis: immunogenetics, pathophysiology, and disease expression

Data are rapidly accumulating documenting disease susceptibility may be linked to genetic markers (DQA1*0501 or related alleles) which are associated with upregulation of IFN-alpha/beta inducible genes elicited in response to an antigen which may be viral. Continued immune-mediated inflammation, resulting in partial lipodystrophy and pathological calcifications, may be fanned by the increased production of TNF alpha usually associated with the TNF alpha-308A allele.

Myositis in children

Idiopathic inflammatory myositis in children includes multiple disease entities, but is primarily made up of juvenile dermatomyositis and, to a lesser degree, juvenile polymyositis. Much new information has been published in the last few years about these diseases, including the epidemiology, pathogenesis, clinical diagnosis, and outcomes and treatment. This includes information on onset of symptoms, potential inciting agents, and regional differences. Exciting data have emerged in our understanding of the immune response gene associations and the description of chimerism in children with these disorders. Finally, new advances in clinical evaluations and outcomes have been described as well as new treatment protocols to provide a more effective therapy with less toxicity. Continued investigation is needed to further understand these diseases, but great strides are being made in our understanding and ability to care for children with idiopathic inflammatory myositis.

Classification and treatment of the juvenile idiopathic inflammatory myopathies

This article reviews the current status of the classification and treatment of the juvenile idiopathic inflammatory myopathies. The intent of classification is to define homogeneous groups that share similar clinical features, disease courses, and responses to therapy. The classification scheme proposed includes clinicopathologic subsets, serologic subjects based on the presence of myositis-specific and myositis-associated autoantibodies, and environmental triggers of myositis. Juvenile dermatomyositis is the most common and widely recognized of these disorders. The second part reviews the history of treatment of juvenile dermatomyositis and discusses agents to consider for patients with refractory disease, unacceptable steroid toxicity, or poor prognostic factors.

The immune effects of neuropeptides

Current evidence indicates that the neuroendocrine system is the highest regulator of immune/inflammatory reactions. Prolactin and growth hormone stimulate the production of leukocytes, including lymphocytes, and maintain immunocompetence. The hypothalamus-pituitary-adrenal axis constitutes the most powerful circuit regulating the immune system. The neuropeptides constituting this axis, namely corticotrophin releasing factor, adrenocorticotrophic hormone, alpha-melanocyte stimulating hormone, and beta-endorphin are powerful immunoregulators, which have a direct regulatory effect on lymphoid cells, regulating immune reactions by the stimulation of immunoregulatory hormones (glucocorticoids) and also by acting on the central nervous system which in turn generates immunoregulatory nerve impulses. Peptidergic nerves are major regulators of the inflammatory response. Substance P and calcitonin gene-related peptide are pro-inflammatory mediators and somatostatin is anti-inflammatory. The neuroendocrine regulation of the inflammatory response is of major significance from the point of view of immune homeostasis. Malfunction of this circuit leads to disease and often is life-threatening. The immune system emits signals towards the neuroendocrine system by cytokine mediators which reach significant blood levels (cytokine-hormones) during systemic immune/inflammatory reactions. Interleukin-1, -6, and TNF-alpha are the major cytokine hormones mediating the acute phase response. These cytokines induce profound neuroendocrine and metabolic changes by interacting with the central nervous system and with many other organs and tissues in the body. Corticotrophin releasing factor functions under these conditions as a major co-ordinator of the response and is responsible for activating the ACTH-adrenal axis for regulating fever and for other CNS effects leading to a sympathetic outflow. Increased ACTH secretion leads to glucocorticoid production. alpha-melanocyte stimulating hormone functions under these conditions as a cytokine antagonist and an anti-pyretic hormone. The sympathetic outflow, in conjunction with increased adrenal activity. leads to the elevation of catecholamines in the bloodstream and in tissues. Current evidence suggests that neuroimmune mechanisms are essential in normal physiology, such as tissue turnover, involution, atrophy, intestinal function, and reproduction. Host defence against infection, trauma and shock relies heavily on the neuroimmunoregulatory network. Moreover, abnormalities of neuroimmunoregulation contribute to the aetiology of autoimmune disease, chronic inflammatory disease, immunodeficiency, allergy, and asthma. Finally, neuroimmune mechanisms play an important role in regeneration and healing.

Elevation of serum creatine phosphokinase during growth hormone treatment in patients with multiple pituitary hormone deficiency

Serum creatinine phosphokinase (s-CPK) increased to more than 500 U/l in 5 out of 21 patients with growth hormone (GH) deficiency during the 2 years of treatment with biosynthetic GH. In three of these five patients, s-CPK had elevated gradually after the start of GH treatment and remained high in one patient except in the period when GH injection was interrupted, and gradually decreased in the other two patients during treatment. These three patients had complete GH deficiency associated with multiple pituitary hormone deficiency due to pituitary stalk transection. One of the remaining two patients had Noonan syndrome and his s-CPK levels before therapy were relatively high. The fifth patient was a baseball athlete and the elevation of s-CPK seemed to be attributable to the strenuous exercise. Conclusion. s-CPK increases significantly in a certain group of patients with GH deficiency during GH replacement therapy. Measurement of s-CPK is to be included in the follow up laboratory tests at least in the 1st treatment year to evaluate the potential hazardous effects of GH on muscle.