Immune-mediated Mechanisms (immune-mediated + mechanism)

Distribution by Scientific Domains


Selected Abstracts


POSTIRRADIATION LUMBOSACRAL RADICULOPLEXOPATHY: IMPROVEMENT AFTER IMMUNE THERAPY

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2000
A. Bersano
A delayed progressive impairment of peripheral nervous system including brachial and lumbosacral radiculoplexopathy is a well-known complication of local radiotherapy. No treatment for this infrequent complication is currently available. Recently, improvement after treatment with high dose immunoglobulin (IVIg) has been reported in some patients, suggesting either an immune-mediated inflammatory nerve damage induced by irradiation or a dysimmune neuropathy (CIDP-like) misdiagnosed as a postirradiation disease. We report on two patients who developed motor lumbosacral radiculoplexopathy several years after local radiotherapy. The first patient (ZA) is a 49 y.o. man developing a progressive proximal>distal weakness and hypotrophy of lower limbs, 20 years after radiotherapy of lumbosacral region for seminoma. Electrophysiological studies showed markedly reduced motor conduction velocities (CV) and prolonged F-wave latencies in lower limb nerves. The second patient (BF), is a 52 y.o. woman who developed progressive left brachial plexopathy and distal>proximal weakness and hypotrophy of lower limbs 12 years after a first course of toracoascellar and lumbar irradiation for Hodgkin lymphoma followed by a second course of cervicoclavicular irradiation for tumor recurrence 7 years later. Electrophysiological studies showed markedly reduced CMAP amplitudes and proportionally reduced CV in motor nerves. No sensory impairment was detected in both patients. CSF protein was elevated in both patients while cells were normal. On the assumption of a possible dysimmune origin of the disease, patient ZA underwent high dose intravenous steroid treatment, while patient BF, who had previously deteriorated after steroids, was treated with IVIg. After treatment, patient ZA became able to walk with less waddling, to rise from the floor and climb stairs without support, and to run. Improvement was less consistent in patient BF, whose right leg strength improved even if she still needed bilateral support to walk. The improvement observed in both patients supports the hypothesis that, at least in some patients, an immune-mediated mechanism may underlie postirradiation radiculoplexopathy. [source]


Association of higher rheumatoid arthritis disease activity during pregnancy with lower birth weight: Results of a national prospective study

ARTHRITIS & RHEUMATISM, Issue 11 2009
Yaël A. de Man
Objective To determine the outcome of pregnancy in women with rheumatoid arthritis (RA) in relation to disease activity and medication use during the pregnancy. Methods In a prospective study, pregnant women with RA were evaluated before conception (when possible), during each trimester of the pregnancy, and postpartum. Clinical characteristics, disease activity, medication use, and pregnancy outcome were analyzed. To examine the independent influence of prednisone use and disease activity on birth weight, regression analyses were performed, with adjustments for gestational age of the child at delivery, the sex of the newborn, and the mother's smoking status, education level, parity, and use of an assisted reproduction technique. Kaplan-Meier curve analyses were performed to examine the association between medication use and gestational age at delivery. Results Data from 152 Caucasian RA patients with singleton pregnancies were available. Both the mean ± SD birth weight (3,379 ± 564 gm) and the mean ± SD birth weight standard deviation score (SDS; +0.1 ± 1.1), which is the birth weight adjusted for the gestational age and sex of the newborn, were comparable with those in the general population. On multiple linear regression analyses of birth weight and birth weight SDS, both of which were adjusted for covariates, only disease activity was associated with lower birth weight (P = 0.025). The gestational age at delivery was significantly lower in women who were taking prednisone (38.8 versus 39.9 weeks; P = 0.001), and their delivery was more often premature (<37 weeks; P = 0.004). Conclusion Pregnancy outcome in women with well-controlled RA is comparable with that in the general population. The effect of prednisone on birth weight is mediated by a lower gestational age at delivery, whereas a higher level of disease activity independently influences birth weight negatively, suggesting an immune-mediated mechanism. [source]


Breed Associations for Canine Exocrine Pancreatic Insufficiency

JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 2 2007
Daniel J. Batchelor
Background:Knowledge of breed associations is valuable to clinicians and researchers investigating diseases with a genetic basis. Hypothesis:Among symptomatic dogs tested for exocrine pancreatic insufficiency (EPI) by canine trypsin-like immunoreactivity (cTLI) assay, EPI is common in certain breeds and rare in others. Some breeds may be overrepresented or underrepresented in the population of dogs with EPI. Pathogenesis of EPI may be different among breeds. Animals:Client-owned dogs with clinical signs, tested for EPI by radioimmunoassay of serum cTLI, were used. Methods:In this retrospective study, results of 13,069 cTLI assays were reviewed. Results:An association with EPI was found in Chows, Cavalier King Charles Spaniels (CKCS), Rough-Coated Collies (RCC), and German Shepherd Dogs (GSD) (all P < .001). Chows (median, 16 months) were younger at diagnosis than CKCS (median, 72 months, P < .001), but not significantly different from GSD (median, 36 months, P= .10) or RCC (median, 36 months, P= .16). GSD (P < .001) and RCC (P= .015) were younger at diagnosis than CKCS. Boxers (P < .001), Golden Retrievers (P < .001), Labrador Retrievers (P < .001), Rottweilers (P= .022), and Weimaraners (P= .002) were underrepresented in the population with EPI. Conclusions and Clinical Implications: An association with EPI in Chows has not previously been reported. In breeds with early-onset EPI, immune-mediated mechanisms are possible or the disease may be congenital. When EPI manifests later, as in CKCS, pathogenesis is likely different (eg, secondary to chronic pancreatitis). Underrepresentation of certain breeds among dogs with EPI has not previously been recognized and may imply the existence of breed-specific mechanisms that protect pancreatic tissue from injury. [source]


Cutaneous manifestations of tuberculosis

CLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 4 2007
J. E. Lai-Cheong
Summary Cutaneous involvement is a rare manifestation of tuberculosis (TB). The correct diagnosis is often significantly delayed because cutaneous TB is not routinely considered in the differential diagnosis or because investigations fail to reveal the presence of Mycobacterium tuberculosis. The clinical features of cutaneous TB are diverse, and result from exogenous and endogenous spread of M. tuberculosis and from immune-mediated mechanisms. The recognition of cutaneous TB is important, as the diagnosis is frequently overlooked resulting in delayed treatment. [source]


Resistance/susceptibility to Echinococcus multilocularis infection and cytokine profile in humans.

CLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2000

Differences have been shown between HLA characteristics of patients with different courses of alveolar echinococcosis (AE). Notably the HLA B8, DR3, DQ2 haplotype was associated with more severe forms of this granulomatous parasitic disease. We compared IL-10, IL-5, interferon-gamma (IFN- ,) and tumour necrosis factor (TNF) secretion by peripheral blood mononuclear cells (PBMC) isolated from eight HLA-DR3+, DQ2+, B8+ AE patients and from 10 HLA-DR3,, DQ2,, B8, patients after non-specific mitogenic and specific Echinococcus multilocularis antigenic in vitro stimulation. PBMC from seven HLA-DR3+, DQ2+, B8+ healthy subjects and nine HLA-DR3,, DQ2,, B8, subjects were also studied as controls. PBMC from AE patients with HLA DR3+, DQ2+ haplotype secreted higher levels of IL-10 without any stimulation and after specific antigenic stimulation than did patients without this haplotype. Higher levels of IL-5 and IFN- , were also produced by these patients' PBMC after stimulation with non-purified parasitic antigenic preparations; however, the specific alkaline phosphatase antigen extracted from E. multilocularis induced only Th2-type cytokine secretion. A spontaneous secretion of TNF by HLA DR3+, DQ2+ B8+ AE patients was also found. These results suggest that HLA characteristics of the host can influence immune-mediated mechanisms, and thus the course of AE in humans; specific antigenic components of E. multilocularis could contribute to the preferential Th2-type cytokine production favoured by the genetic background of the host. [source]