Le syndrome de l’homme raide : formes cliniques, traitement et profil évolutif

INTRODUCTION

Stiff-Man syndrome (SMS) is a rare neurological disease first described fifty years ago. There are several clinical forms, which are frequently misdiagnosed. The aim of this study is to review three of the main clinical forms.

MATERIAL AND METHODS

Case reports concerning three women suffering from different forms of SMS are presented, giving the main clinical features, their associations with other diseases, and the biological and electrophysiological findings.

RESULTS

The first patient presented a symmetric axial muscle rigidity, painful spasms and contractions of the trunk and limbs associated with anti-GAD antibodies. The common form of SMS was diagnosed and the patient was improved by intravenous immunoglobulin (IVIg). The second patient suffered from contractions and spasms localized to the lower limbs. In this patient, anti-GAD antibodies were absent. The Stiff-Leg syndrome was diagnosed and the patient was improved by intrathecal baclofen. The third patient presented rigidity of limb and trunk muscles associated with signs of encephalitis. In this patient, only anti-amphiphysin antibodies were present. The progressive encephalomyelitis with rigidity was diagnosed and the patient was improved by IVIg associated with corticosteroid.

CONCLUSION

Identifying patients with SMS makes it possible to propose appropriate medical management. There are several forms of the disease, and the severity of the evolution differs in each case. Treatment with GABA-ergic inhibitory drugs, IVIg and corticosteroid improve both the symptomatology and the quality of life of these patients.

Sudden spasms following gradual lordosis—the stiff-person syndrome

BACKGROUND

A 28-year-old woman presented to hospital after an episode of severe lower back spasms that occurred during a stressful family gathering. She had a history of progressive difficulty bending forward and increasing lumbar lordosis.

INVESTIGATIONS

Physical examination, spine MRI scan, abdominal and pelvic ultrasound, electromyogram, nerve conduction studies, cerebrospinal fluid analysis, breast examination, Pap smear, transabdominal and endovaginal ultrasound.

DIAGNOSIS

Stiff-person syndrome with high titer of antibodies against glutamic acid decarboxylase.

TREATMENT

Benzodiazepines and intravenous immunoglobulins.

Intravenous immunoglobulin: striving for appropriate use

BACKGROUND

Intravenous immunoglobulin (IVIG) is the mainstay therapy in human immune deficiency states characterized by qualitative and quantitative reductions in B cells. In addition, however, there is widespread use of IVIG in a number of other areas, including neuroimmunologic, infectious, dermatologic, hematologic, autoimmune, inflammatory and idiopathic disorders. In many of these cases, there are little objective data to support the use.

METHODS

We performed a review of more than 400 publications in PubMed using the key words 'intravenous immunoglobulin' and excluded publications that focused on immune deficiency, for which the indication for IVIG is already clear.

RESULTS

For a number of off-label indications, there is significant evidence of efficacy and IVIG has become the standard of care for many clinical syndromes other than immune deficiency. In some conditions, however, the data have not been well controlled or randomized and are often limited to case reports that are difficult to interpret. Although the critical shortage of IVIG of the last decade is no longer an issue, IVIG is expensive and not without risk. The use of IVIG should be based not only on clinical data, but also, and especially, on the biological rationale for its use.

CONCLUSIONS

The appropriate use of IVIG is an important issue that is difficult to resolve, and will continue to challenge clinicians based on expense and potentially limited supply, including the intrinsic limitations of donor plasma. The establishment of national and international voluntary registries to report use of IVIG in disorders for which evidence is lacking would be a first step toward facilitating randomized, controlled clinical trials.

[Stiff-person syndrome--two Hungarian cases and review of the literature]

The stiff-man syndrome is a rare neurological disorder characterized by progressive stiffness of the axial muscles and co-contraction of agonist and antagonist muscles sometimes accompanied by involuntary sudden muscle spasms. The disease is thought to be caused by immunological changes leading to a GABA transmission disturbance, but the precise pathogenesis is not clear. Two Hungarian cases are presented in this article accompanied by a review of the literature. The aim of the paper is to call the attention on this presumably underdiagnosed disease. The diagnostic laboratory tests of the disease are available in Hungary.

The role of IVIg in the treatment of patients with stiff person syndrome and other neurological diseases associated with anti-GAD antibodies

INTRODUCTION

High-titre anti-GAD antibodies are characteristically seen in patients with stiff person syndrome (SPS). Other CNS disorders, rarely associated with high anti-GAD antibody titres, include: a) SPS-plus, a syndrome characterised by SPS and cerebellar ataxia; b) Batten's disease; and c) rare patients with epilepsy and idiopathic cerebellar ataxia. Currently, high-titre anti- GAD antibodies serve only as markers of an autoimmune process within the CNS because their pathogenic role in the afore-mentioned disorders has not been established. In SPS, there is evidence of autoimmune pathogenesis based on: the association of the disease with other autoimmune disorders or autoantibodies; immunogenetic background; presence of oligoclonal IgG bands in the CSF with increased intrathecal anti-GAD antibody synthesis and response to immunotherapies. SPS is the only GAD-positive CNS disease where a controlled study with immunotherapy has been conducted.

METHODS

Sixteen anti-GAD antibody-positive patients were randomised to receive IVIg or placebo for 3 months. After a washout, they crossed to the alternative therapy for another three months. Efficacy was based on the difference in scores of the distribution of stiffness index and heightened sensitivity (spasms) from baseline to the second and third month of the infusions. Direct treatment and carry-over effect were compared for both groups.

RESULTS

The stiffness scores in the IVIg-randomised patients declined significantly from month 1 through 4, but rebounded when they crossed to placebo. In contrast, the scores in the placebo-randomised group remained constant from month 1-4 but dropped significantly after crossing to IVIg. Eleven patients who received IVIg became able to walk unassisted, stopped falling and assumed household or work duties. The duration of benefit varied from 6-12 weeks or up to a year. The anti-GAD(65) antibody titres declined after IVIg, but not after placebo.

CONCLUSION

Based on a controlled study, IVIg is a safe and effective therapy for SPS in patients unresponsive to other agents. Whether IVIg has a role in the other GAD-positive patients with neurological disease, or in SPS patients without GAD antibodies, remains unknown.

Stiff-Person Syndrome

BACKGROUND

Stiff-person syndrome (SPS) is a rare neurologic disorder with autoimmune features. It is characterized by progressive, severe muscle rigidity or stiffness most prominently affecting the spine and lower extremities.

REVIEW SUMMARY

Superimposed muscle spasms result in simultaneous contraction of agonist and antagonist muscles which are detectable by electromyography (EMG) and relieved by administration of benzodiazepines. The exacerbation of SPS by emotional stressors often results in the referral of these patients for psychiatric assessment although this was more common before the discovery of an association with antibodies to glutamic acid decarboxylase (GAD antibodies). Formerly known as stiff-man syndrome, the female to male ratio is 2:1 and the principle paraneoplastic variant is associated with breast cancer. Although rare, this is a disease of middle age that severely curtails the functional capacity of those it strikes. It is frequently associated with diabetes and other autoimmune diseases. IVIg is recently demonstrated to be effective in the treatment of SPS; diazepam remains useful in managing the symptoms.

CONCLUSIONS

This article summarizes the history of SPS, describes important clinical features, discusses management, touches upon areas of uncertainty, and postulates some avenues for research.

Neuropathology and binding studies in anti-amphiphysin-associated stiff-person syndrome

The authors report a 71-year-old woman with amphiphysin-associated paraneoplastic stiff-person syndrome, opsoclonus, and encephalopathy. The patient's symptoms temporarily responded to plasmapheresis in parallel with a decline of serum anti-amphiphysin antibody titers. Later, the encephalopathy progressed rapidly and the patient died. Binding studies and the detection of autoantibodies in the patient's CNS as well as the treatment response suggest a pathogenic role of the anti-amphiphysin antibodies.

['Stiff-person'-syndrome]

In two patients, a man aged 54 years and a woman aged 49 years, stiff-person syndrome was diagnosed. This is a rare disorder of the central nervous system, with signs of an autoimmune pathogenesis. Patients present with pain and stiffness of the lower back, a complaint that is regularly seen in general practice. Moreover, the disease causes hypertonia and very painful cramps of the lower back and legs. Electromyographic examination in the resting condition reveals continuous muscle activity in the long back muscles, which decreases following the administration of diazepam. In 60% of patients, antibodies to glutamic acid decarboxylase may be found in the serum or cerebrospinal fluid; this enzyme is involved in the production of the inhibiting neurotransmitter gamma-aminobutyric acid. Both patients were treated with diazepam, baclofen and corticosteroids. Stiff-person syndrome is a rare but treatable disorder that should be considered when patients present with stiffness and pain in the lower back and upper legs.

Paraneoplastic neurologic syndromes: approaches to diagnosis and treatment

There is increasing evidence that many paraneoplastic neurologic syndromes are immune-mediated. Because symptoms usually have an acute onset and precede the tumor diagnosis, the recognition of a neurologic disorder as a paraneoplastic syndrome is challenging. The poor response to treatment of many paraneoplastic neurologic syndromes has been attributed to the early, irreversible pathological changes involving the nervous system. This may account for the more frequent responses to therapy of some paraneoplastic neurologic syndromes affecting the peripheral nerves and neuromuscular junction compared with those that produce neuronal degeneration. This review focuses on the current therapeutic approaches to immune-mediated paraneoplastic neurologic syndromes, including prompt recognition of the disorder, detection and treatment of the associated tumor, and, in some disorders, immunosuppressive therapy.

[Successful treatment of the backward-bending attack due to generalized spasm in stiff-person syndrome with intravenous immune globulin therapy]

We report a 63-year-old man with stiff-person syndrome, who dramatically responded to the treatment with high dose intravenous immunoglobulin (IVIG). He developed stiffness of the right leg and low back five years ago. He was treated with oral diazepam 6 mg/day and showed a marked improvement. He had been maintained on the same dose since then. In 2000, he began to have episodic generalized spasm and painful spasm of his left leg as well as persistent stiffness of his legs and low back. Findings on the physical examination were normal except for a prominent hyperlordosis with co-contracture of the lumbar paraspinal and abdominal muscles. Neurologic examination revealed stiffness in the lower limbs, more marked on the left side, and lower truncal muscles. The left leg had painful spasm, which was provoked by tactile stimuli. There was severe generalized spasm which made him suddenly bend backward. These backward-bending attacks were provoked spontaneously or reflexively by sudden tactile stimuli. He was unable to arise from a chair or stand without assistance. His deep tendon reflexes on both legs were brisk and Babinski sign was negative. He had no diabetes mellitus and thyroid function was normal. Antibodies against glutamic acid decarboxylase(GAD), antinuclear antibody, thyroid peroxidase autoantibody and antithyroglobulin autoantibody in the serum were present. His painful spasm was disappeared and muscle stiffness was moderately improved by treatment with oral diazepam and clonazepam, but backward-bending attacks due to generalized spasms were not controlled. He received IVIG. Three days after the administration of IVIG, these attacks disappeared completely. Subsequently muscle stiffness improved. One week after, he was able to walk without assistance. IVIG may be useful for treatment of generalized spasm, which had no response to treatment with diazepam or clonazepam.

The stiff-person syndrome. Case report

The stiff-person syndrome is a rare and disabling disorder, characterized by muscle rigidity with superimposed painful spasms involving axial and limb musculature. The clinical symptoms are continuous contraction of agonist and antagonist muscles caused by involuntary motor-unit firing at rest and the spasms that are precipitated by tactile stimuli, passive strach, volitional movement of affected or unaffected muscles, startling noises and emotional stimuli. Both the rigidity and the spasms are relieved by sleep, general anaesthesia, myoneural blockade and peripheral nerve blockade. The cause of the stiff-person syndrome is unknown but an autoimmune pathogenesis is suspected because 1) the presence in the cerebrospinal fluid (CSF) of antibodies against glutamic acid decarboxylase (GAD), the rate-limiting enzyme for the synthesis of the inhibitory neurotrasmitter gamma-aminobutyric acid (GABA), 2) the association of the disease with other autoimmune disorders, 3) the presence of various autoantibodies and 4) a strong immunogenetic association. The stiff-person syndrome is clinically elusive but potentially treatable and should be considered in patients with unexplained stiffness and spasms. Drugs that enhance GABA neurotransmission, such as diazepam, vigabatrin and baclofen, provide modest relief of clinical symptoms. Immunomodulatory agents such as steroids, plasmapheresis and intravenous immunoglobulin, seem to offer substantial improvement.

[Successful treatment in a patient with a focal form of stiff-person syndrome using plasma exchange and intravenous immunoglobulin therapy]

We report a 42-year-old female with continuous muscle stiffness and painful muscle spasms of the right leg. The symptoms developed suddenly and worsened over the week after onset. At hospitalization, the right leg had a fixed posture of extension and the foot was plantar-flexed and internally rotated. Neurological examination revealed hyperreflexia of the right knee with positive Chaddock's sign, and stiffness and painful spasms located in the right leg, exaggerated by sudden auditory and tactile stimuli or by emotional stress. She could not walk due to her stiffness. There were no signs of rigidity in the left leg, upper extremities, or truncal muscles. Electrophysiological examinations revealed continuous muscle discharge. High titers of anti-glutamic decarboxylase (GAD) antibodies were detected in serum (140,000 U/ml) and cerebrospinal fluid (1,347 U/ml), confirming that the patient suffered from stiff-leg syndrome. Systemic evaluation revealed no malignant neoplasm, but revealed euthyroid Hashimoto's disease. Stiff-leg syndrome in this case was unresponsive to pharmacotherapy with diazepam and was unchanged for the first month of hospitalization. Plasma exchange therapy alleviated the clinical symptoms and decreased the anti-GAD antibody titer. After IVIg therapy, the symptoms and signs have dramatically disappeared to date but the titer of anti-GAD antibodies in serum recurred after an initial fall. To our knowledge, this is the first case of stiff-leg syndrome in Japan.

[Stiff limb syndrome associated with Hashimoto's encephalopathy: improvement after corticotherapy]

Stiff limb syndrome is a recently described variant of stiff man syndrome and is characterized by limb stiffness and spasms. Unlike stiff man syndrome, stiff limb syndrome is rarely associated with anti GAD antibodies, poorly improves after symptomatic treatment, and has a relapsing and remitting course. Both stiff man and stiff limb syndromes are frequently associated with auto-immune diseases. We report a case of a 70-year old man who presented with a stiff limb syndrome associated with symptoms highly suggestive of Hashimoto's encephalopathy. The signs of encephalopathy dramatically resolved after corticosteroid treatment, and remissions was complete after 12 months. The stiff limb syndrome had a remitting course despite symptomatic treatment including diazepam, baclofen and vigabatrin and immunomodulating treatments including corticoid and intravenous immunoglobulins.

Atypical low back pain: stiff-person syndrome

Stiff-person syndrome was diagnosed in a patient with chronic low back pain. The diagnosis of this rare neurological condition rests mainly on the clinical findings of axial and proximal limb rigidity, increased lumbar lordosis often accompanied with pain, and normal neurological findings apart from brisk deep tendon reflexes. Electromyography of the lumbar paraspinal muscles shows motor unit firing at rest with normal appearance of the motor unit potentials. Titers of antibody to glutamic acid decarboxylase are elevated. Diazepam is the treatment of reference. Physical therapy can substantially improve quality of life.

Plasma exchange in stiff-man syndrome

Stiff-man syndrome (STS) is a rare neurological disorder characterized by involuntary axial and proximal limb rigidity and continuous motor unit activity on electromyography (EMG). Autoantibodies to glutamic acid decarboxylase (GAD) present in 60% of the patients are implicated. We report on the use of plasma exchange (PE) in 2 patients with STS whose serum and cerebrospinal fluid were negative for GAD autoantibodies. One patient showed minimal clinical improvement following PE while the second reported subjective improvement, but not any different from that with medications. Based on the results of PE in our patients, it seems that those who are autoantibody negative are less likely to respond. Whether a more aggressive approach to PE will be beneficial remains speculative.

Double filtration plasma exchange and immunoadsorption therapy in a case of stiff-man syndrome with negative anti-GAD antibody

We report the effects of double filtration plasma exchange and immunoadsorption therapy which were performed for a case of stiff-man syndrome even though the patient was negative for anti-glutamic acid decarboxylase (GAD) antibody. The patient underwent a course of four double filtration plasma exchanges, which resulted in marked clinical improvement. Painful muscle cramps disappeared and muscle stiffness reduced within a day after the first plasma exchange. The patient's improvement continued, but his condition declined again about ten months after plasma exchange. Immunoadsorption therapy was then performed, and this treatment was also effective.