[Botulism toxin in practice]

Tear osmolarity, dry eye syndrome, blepharospasm and botulinum neurotoxin

PURPOSE

To assess the severity of dry eye disease in patients with blepharospasm (BEB) before (control) and after injection of botulinum neurotoxin A (BoNT/A).

DESIGN

Cross-sectional study.

METHODS

Patients with clinically diagnosed BEB and no known history of dry eye syndrome prior to the onset of the disease, before (controls) or after injection with one of the three available types of BoNT/A: onabotulinumtoxinA (Botox®; Allergan, Irvine, CA, USA), abobotulinumtoxinA (Dysport®; Beaufour Ipsen Pharma SAS, Paris, France) or incobotulinumtoxinA (Xeomin®; Merz Pharma GmbH, Frankfurt, Germany) every 3 months. Tear osmolarity and Schirmer's I-test were measured at the first visit for non-treated BEB patients as controls and 3 months after BoNT/A injection.

RESULTS

The study consisted of 101 BEB patients (86 females, 15 males) with a mean age of 67 years (range 30-86 years). Seventeen patients were untreated, 26 treated with onabotulinumtoxinA, 23 treated with abobotulinumtoxinA and 35 treated with incobotulinumtoxinA. Post-injection mean tear osmolarity was not significantly higher among patients treated with onabotulinumtoxinA, abobotulinumtoxinA, or incobotulinumtoxinA (P=0.65, P=0.92, and P=0.15, respectively), compared to controls, remaining less than 308 mosm/mL. Mean Schirmer's I-test results remained under 5mm and did not vary between the four groups.

CONCLUSIONS

The results clearly demonstrate that reduced tear secretion appears to be present in BEB patients even prior to treatment. This decreased lacrimal secretion was not correlated with hyperosmolarity. Clinicians should proactively treat dry eye syndrome in conjunction with management of the blepharospasm.

Botulism and Bioterrorism: How Serious is This Problem?

Botulism is a potentially lethal disease caused by one of seven homologous neurotoxic proteins usually produced by the bacterium,Clostridium botulinum. This neuromuscular disorder occurs through an exquisite series of molecular events, ultimately ending with the arrest of acetylcholine release and hence, flaccid paralysis. There are three types of botulism: food, wound, and infant botulism. Most strains of the bacterium produce a potent, respiratory muscle-paralyzing neurotoxin, botulinum toxin (BTX). It can lead to death unless appropriate therapy is promptly initiated. Due to the severity and potency of BTX, its importance as a biological weapon is of major concern to public health officials. Nevertheless, BTX is also medicament.

[Botulinum toxin A: analgesic treatment for temporomandibular joint disorders]

INTRODUCTION

Pain, along with clicking, sub-luxation, and blocking, is one of the main symptoms for patients presenting with temporomandibular joint disorders. We assessed the effectiveness of botulinum toxin A (BOTOX(®), Allergan) as analgesic treatment for temporomandibular joint disorders.

PATIENTS AND METHOD

Twenty-six patients with chronic pain linked to temporomandibular joint disorders were prospectively assessed. Botulinum toxin A was injected in masseter and temporalis muscles. Follow-up parameters, at one and three months, were: measuring mouth opening and diduction, muscle tenderness and pain using a visual analogue scale.

RESULTS

There was a significant (P<0.0001) decrease of pain, an increased mouth opening, and diduction at three months. Seventy percent of the patients felt less muscle tenderness. The patient felt his psychological state had improved and so did his family.

DISCUSSION

Botulinum toxin A significantly decreases pain and improves movements of patients presenting with temporomandibular joint disorders. The effects are prolonged three months after the injection.

Botulinum toxin and anal fissure: efficacy and safety systematic review

PURPOSE

The main purpose of this study was to investigate the efficacy and safety of botulinum toxin in the treatment of anal fissure. An answer was attempted to the following research questions: (i) what is the efficacy of botulinum toxin in healing of anal fissure compared to placebo, (ii) what is the efficacy of botulinum toxin in healing of anal fissure compared to other means of chemical sphincterotomy, (iii) what is the efficacy of botulinum toxin in healing of anal fissure compared to surgical sphincterotomy, (iv) what is the short term safety of botulinum toxin injections and (v) what is the long term safety of botulinum toxin injections.

METHODS

Clinical trials investigating the effect of botulinum toxin in the treatment of anal fissure met inclusion criteria. Case reports and case series were also included for the estimation of safety. Meta-analysis was not performed due to clinical heterogeneity.

RESULTS

The comparator could be placebo, nitroglycerin ointment, or lateral internal sphincterotomy, with dosage ranging from 20 IU to 50 IU of botulinum toxin. Fissure healing was the most commonly reported primary endpoint but the time period from botulinum toxin injection to fissure healing ranged from 2 weeks to 4 months. Accordingly, outcome data were also heterogenous.

CONCLUSIONS

Botulinum toxin injections should be considered a minimally invasive therapeutic option for the treatment of chronic anal fissure. However, well designed randomized trials are needed for the valid estimation of the efficacy and safety of botulinum toxin in this therapeutic indication.

[Spasticity: clinical and imaging features]

Spasticity, a component of the pyramidal syndrome, characterized by increased tonic stretch reflexes and hyperactive deep tendon reflexes, occurs in patients with central nervous system lesions (stroke, brain or cord injury, multiple sclerosis, cerebral motor impairment). The implementation of standard procedures (patient positioning, increased examination time, turning off certain devices before MR imaging) allows the acquisition of high quality examinations in spastic patients. Worsening spasticity in a handicaped patients is due to an irritative process (deep seated infection, fracture, syrinx...) usually detectable with imaging. Ultrasound or CT guided injections of botulinum agents provides radiologists with the opportunity to further participate in the management of spastic patients.

Évaluation d'une procédure antalgique associant protoxyde d'azote et crème EMLA lors des injections de toxine botulique chez l'enfant

AIMS

To evaluate the efficiency and tolerance of analgesic treatment with nitrous oxide and topical eutectic mixture of local anesthetics (EMLA) in children undergoing botulinum toxin injections for focal spasticity.

METHODS

Prospective study including 40 consecutive patients aged 2 to 17 years, most with cerebral palsy, undergoing botulinum toxin injections. Ten had severe cerebral palsy with cognitive deficiency. For most patients the treatment involved several muscles, with several injections per muscle. The total number of injections varied from 1 to 25. The procedure was performed with topical anesthesia with EMLA and inhalation of nitrous oxide (50% nitrous oxide, 50% oxygen). Reactions were recorded by the staff (a practician, a nurse, an auxiliary staff member and an internist) and whether they related to the injection or were nonspecific.

RESULTS

A total of 45% of patients showed no clinical manifestation of pain; for 30%, reactions were crying and withdrawal directly related to the injections; and for 25%, manifestations seemed nonspecific and mainly related to overall anxiety and discomfort. In 3 patients, moderate side effects were observed (visual hallucinations and euphoria).

DISCUSSION

Nitrous oxide analgesic with topical EMLA was efficient for children undergoing botulinum toxin injections but remained insufficient for half of our patients, and modification of the protocol is needed in some cases. Precise evaluation of acute pain is difficult in children with major cognitive deficits. Clinical manifestations are related to pain but also to overall anxiety and stress.

Toxine botulique et fissure anale chronique

Lateral internal sphincterotomy is widely used in the treatment of chronic anal fissure. However, it is associated with a high rate of irreversible incontinence. For this reason the botulinum toxin has become a medical means of reversible sphincterotomy. Indeed, this neurotoxin induces relaxation of the smooth internal anal sphincter lasting one to three months after one injection. We reviewed the published studies about the use of this technique in the management of chronic anal fissure. Healing occurred in more than 70% of fissures without irreversible incontinence. Although further studies are needed to determine the best modalities of administration, especially due to the remaining significant recurrence rate, this toxin may be a valuable treatment for chronic anal fissure in the future.