L.H. Visser

Risk factors for the development of polyneuropathy and myopathy in critically ill patients.

Background Previously, mainly retrospective and a few important prospective studies postulated the role of sepsis or systemic inflammatory response syndrome (SIRS), multiple organ failure, and the use of medication as causative factors for the development of critical illness polyneuropathy and myopathy (CIPNM). This study aimed to identify the risk factors in the development of CIPNM. Methods Prospectively, we studied 98 patients who were on artificial respirators for the development of CIPNM. The Acute Physiology and Chronic Health Evaluation (APACHE) III score, presence of SIRS, and sepsis severity score at entry; the dosage of midazolam, vecuronium, and steroids at entry and day 7 of artificial respiration; and the use of aminoglycosides at entry were related with time to CIPNM or time of last follow-up. The Kaplan-Meier method and log-rank test were used. Results Thirty-two patients (33%) developed CIPNM. After multivariate analysis, it was found that the APACHE III score and the presence of SIRS were significantly related with risk for the development of CIPNM. No significant relation was found for the use of midazolam, vecuronium, or steroids. Based on a risk index from a Cox regression model with APACHE III score and presence of SIRS as outcomes, three groups could be constructed with low-, medium-, and high-risk patients for the development of CIPNM. Conclusions The APACHE III score, a quantitative index of disease severity based on clinical and laboratory physiologic data, is a valuable predictor for the development of CIPNM in patients in the intensive care unit. Together with the presence of SIRS, it can be used to estimate the risk of developing CIPNM for patients on artificial respirators.

Effect of methylprednisolone when added to standard treatment with intravenous immunoglobulin for Guillain-Barré syndrome: Randomised trial

BACKGROUNDnDespite available treatment with intravenous immunoglobulin (IVIg), morbidity and mortality are considerable in patients with Guillain-Barré syndrome (GBS). Our aim was to assess whether methylprednisolone, when taken with IVIg, improves outcome when compared with IVIg alone.nnnMETHODSnWe did a double-blind, placebo-controlled, multicentre, randomised study, to which we enrolled patients who were unable to walk independently and who had been treated within 14 days after onset of weakness with IVIg (0.4 g/kg bodyweight per day) for 5 days. We assigned 233 individuals to receive either intravenous methylprednisolone (500 mg per day; n=116) or placebo (n=117) for 5 days within 48 h of administration of first dose of IVIg. Because age is an important prognostic factor, we split treatment groups into two age-groups-ie, younger than age 50 years, or 50 years and older. Our primary outcome was an improvement from baseline in GBS disability score of one or more grades 4 weeks after randomisation. Analysis was by intention to treat.nnnFINDINGSnWe analysed 225 patients. GBS disability scores increased by one grade or more in 68% (76 of 112) of patients in the methylprednisolone group and in 56% (63 of 113) of controls (odds ratio [OR] 1.68, 95% CI 0.97-2.88; p=0.06). After adjustment for age and degree of disability at entry, treatment OR was 1.89 (95% CI 1.07-3.35; p=0.03). Side-effects did not differ greatly between groups.nnnINTERPRETATIONnWe noted no significant difference between treatment with methylprednisolone and IVIg and IVIg alone. Because of the relevance of prognostic factors and the limited side-effects of methylprednisolone, the potential importance of combination treatment with the drug and IVIg, however, warrants further investigation.

Cytomegalovirus infection and Guillain-Barre syndrome The clinical, electrophysiologic, and prognostic features

Guillain-Barre syndrome (GBS) is usually preceded by infections, in particular cytomegalovirus (CMV) and Campylobacter jejuni infection. We studied the clinical and electrophysiologic features of 20 CMV-associated GBS patients and compared the findings with earlier established data of C. jejuni-related GBS patients (n = 43) and of GBS patients without these infections (n = 71). The patients all participated in the Dutch GBS trial in which we compared the effect of intravenous immune globulins and plasma exchange. We demonstrate that CMV-related GBS patients have a different clinical pattern in comparison with the other two GBS groups. They are significantly younger, initially have a severe course indicated by a high frequency of respiratory insufficiency, and often develop cranial nerve involvement and severe sensory loss. This is in contrast to C. jejuni infection, which is associated with motor GBS. Both infections are associated with delayed recovery compared with the GBS patients without these infections. NEUROLOGY 1996;47: 668-673

Critical illness polyneuropathy and myopathy (CIPNM): evidence for local immune activation by cytokine-expression in the muscle tissue.

In a longitudinal prospective study a muscle biopsy was taken from 30/32 (33%) of the 98 patients who developed critical illness polyneuropathy and myopathy (CIPNM). Neuropathic changes were found in 37%, myopathic in 40%, and a combination in 23% of the biopsies. The immunohistopathology showed macrophages and Th-cells in 40% and 60% of the muscle biopsies respectively. Small mainly perivascular infiltrates contained macrophages and Th-cells. ICAM-1, VCAM and MAC were found on the vascular endothelium in 58%, 53% and 79% respectively. In all biopsies there was an upregulation of both HLA-I and HLA-DR. Proinflammatory cytokines and TNFalphaR75 were also produced locally (IL-1beta in 71%, IFN-gamma in 40%, IL-12 in 73%, TNFalphaR75 in 90%). The anti-inflammatory cytokine IL-10 was simultaneously expressed in 96% of the biopsies. HLA-DR, TNFalphaR75 and IL-10 differed significantly when compared with control muscle biopsies. Our data provide evidence that small numbers of activated leukocytes producing both pro- and anti-inflammatory cytokines infiltrate skeletal muscle of CIPNM patients. We propose that the local balance of leukocyte activities is of importance in the pathophysiology of muscle weakness in CIPNM.

Prognostic factors of Guillain-Barré syndrome after intravenous immunoglobulin or plasma exchange

Objective: To determine the influence of clinical, laboratory, and electrodiagnostic factors on the prognosis of Guillain-Barré syndrome (GBS). Background: Identification of prognostic factors may lead to better selection of patients with a poor prognosis for new therapeutic trials. Methods: The authors studied 147 patients with GBS who participated in the Dutch GBS trial comparing the effect of IV immunoglobulins with plasma exchange (PE). Outcome was measured at 8 weeks because half of the patients had recovered independent locomotion by then and at 6 months, the endpoint of the study. Results: Multivariate logistic regression revealed the following factors predicting outcome (inability to walk independently) at 8 weeks: a preceding gastrointestinal illness (yes, no), age (≥50, <50 years), Medical Research Council sum score (<40, ≥40) at the start of treatment, and—described for the first time—a recent cytomegalovirus (CMV) infection (yes, no). At 6 months, the same clinical factors were found, but an initial rapid progression of weakness also appeared to be a prognostic factor. Analysis of treatment interactions revealed that the effect of diarrhea was more pronounced in the PE-treated group. Conclusions: The main predictors of outcome in GBS are clinical factors. Diarrhea is an important poor predictor of outcome, especially for the PE-treated group, and a recent CMV infection predicts delayed early recovery.

Difference in distribution of muscle weakness between myasthenia gravis and the Lambert–Eaton myasthenic syndrome

Background: Myasthenia gravis and the Lambert–Eaton myasthenic syndrome (LEMS) may have a similar distribution of muscle weakness. Deciding on a diagnosis of myasthenia gravis or LEMS on clinical grounds may therefore be difficult. Objective: To compare the localisation of initial muscle weakness and the distribution of weakness at the time of maximum severity in patients with myasthenia gravis and LEMS. Subjects: 101 patients with myasthenia gravis and 38 patients with LEMS. Results: In myasthenia gravis, initial weakness involved extraocular muscles in 59%, bulbar muscles in 29%, and limb muscles in 12% of the patients. In LEMS no patient had ocular weakness, 5% had bulbar weakness, and 95% had weakness of the limbs as the first symptom (p < 0.001). At the point of maximum severity, weakness in myasthenia gravis was purely ocular in 25%, oculobulbar in 5%, restricted to the limbs in 2%, and present in both oculobulbar muscles and limbs in 68%. At this point, none of the LEMS patients had weakness restricted to extraocular or bulbar muscles (p = 0.002). The legs were affected in all LEMS patients, whereas in 12 patients with generalised myasthenia gravis limb weakness was restricted to the arms (p = 0.024). Conclusions: In a patient suspected to have a myasthenic syndrome whose first symptom is ocular weakness, LEMS is virtually excluded. Limb weakness confined to the arms is only found in generalised myasthenia gravis and not in LEMS. Muscle weakness in myasthenia gravis tends to develop in a craniocaudal direction, and in the opposite direction in LEMS.

Guillain-Barré Syndrome: Multifactorial Mechanisms versus Defined Subgroups

The clinical spectrum of Guillain-Barré syndrome (GBS) is summarized in relation to antecedent infections and anti-ganglioside antibodies. Associations exist between a pure motor form of GBS, diarrhea, Campylobacter jejuni infection, and anti-GM1 antibodies; between cranial nerve involvement and Miller Fisher syndrome, C. jejuni infection, and anti-GQ1b antibodies; and between variants, such as severe sensory involvement and cytomegalovirus infection. These three clinical variants are suggested to form the extremes of a continuous spectrum; they are discussed in relation to the more pathologically defined patterns of acute motor axonal neuropathy and acute motor-sensory axonal neuropathy. In particular, patients with a clinically pure motor variant of GBS, diarrhea, anti-GM1 antibodies, or C. jejuni infection seem to respond better to early treatment with high-dose immunoglobulins than to plasma exchange.

The epidemiology of the Lambert-Eaton myasthenic syndrome in the Netherlands

The Lambert-Eaton myasthenic syndrome (LEMS) is presumed to be rare, but epidemiologic studies in large circumscribed populations have not been performed. Small cell lung carcinoma (SCLC) is said to be present in about 50% of LEMS patients, but this frequency might be subject to bias, as estimates were based on retrospective data from large specialized centers.1–4⇓⇓⇓ We established the prevalence and incidence of LEMS and the frequency of underlying SCLC in the Netherlands.nnThe study period ran from July 1, 1998, to July 1, 2003, and concerned the entire Netherlands, with 16,221,695 inhabitants by July 1, 2003. All eight university hospitals and eight large neurologic centers participated in this study. Patients were identified through standard hospital databases using codes 358.0 and 358.1 of the International Classification of Diseases, 9th revision, or using the Dutch neurologic coding system according to Kortbeek, or using the neuromuscular databases in the university hospitals. To overcome a possible referral bias we sent a letter to all neurologists in the Netherlands in a search for other LEMS patients, backed by additional attention to the aims of this study by publications in Dutch medical journals and presentations to neurologists and pulmonologists. Case finding was started on July …

The Dutch neuromuscular database CRAMP (Computer Registry of All Myopathies and Polyneuropathies): development and preliminary data.

Each of the various neuromuscular diseases is rare. Consequently, solid epidemiological data are not available and it is often difficult to find sufficient patients for studies. For this reason, the Dutch neuromuscular database, CRAMP (Computer Registry of All Myopathies and Polyneuropathies), was developed in 2004 by the Dutch Neuromuscular Research Support Centre, to store information on patient characteristics and diagnoses (based on Rowland and McLeods classification) in a uniform and easily retrievable manner. Care was taken to preserve data confidentiality. It is envisaged that CRAMP will prove particularly useful for studies in which multicentre collaboration is needed to recruit a sufficiently large number of patients. More than 10,000 patients with neuromuscular diseases (4,837 female, 5,476 male) have been registered since 2004, half of whom (n=5059) have peripheral nerve disorders.

HLA class I and II in Lambert-Eaton myasthenic syndrome without associated tumor

Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune disorder, in which antibodies against voltage-gated calcium channels located at nerve terminals cause muscle weakness and autonomic dysfunction. In approximately half of the patients the autoimmune process is initiated by a tumor. In the other half of patients no tumor is found and the etiology is unknown. The aims of this study were to investigate the strength of HLA-associations with nontumor LEMS (NT-LEMS) and to study the relation of HLA-haplotypes with age at onset of LEMS and other clinical features. Therefore, typing of HLA class I and II was performed in 19 patients with NT-LEMS, who were clinically evaluated. NT-LEMS was significantly associated with alleles of both HLA-class I (i.e. HLA-B8) as well as -class II (i.e. HLA-DR3 and -DQ2). HLA-B8+ patients had significantly younger age at onset of LEMS and tended to be female. This study shows that HLA-class I haplotype is associated with a distinct phenotype in NT-LEMS.