Local Tetanus Begins with a Neuromuscular Junction Paralysis around the Site of Tetanus Neurotoxin Release due to Cleavage of the Vesicle-Associated Membrane Protein

Local tetanus develops when limited amounts of tetanus neurotoxin (TeNT) are released by Clostridium tetani generated from spores inside a necrotic wound. Within days, a spastic paralysis restricted to the muscles of the affected anatomical area develops. This paralysis follows the retrograde transport of TeNT inside the axons of motoneurons and its uptake by inhibitory interneurons with cleavage of a vesicle-associated membrane protein required for neurotransmitter release. Consequently, incontrollable excitation of motoneurons causes contractures of innervated muscles and leads to local spastic paralysis. Here, the initial events occurring close to the site of TeNT release were investigated in a mouse model of local tetanus. A peripheral flaccid paralysis was found to occur, before or concurrent to the spastic paralysis. At variance from the confined TeNT proteolytic activity taking place within motor neuron terminals, central protein cleavage was detected within inhibitory interneurons controlling motor neuron efferents innervating muscle groups distant from the site of TeNT release. These results indicate peripheral activity of TeNT in tetanus and explains why the spastic paralysis observed in local tetanus, although confined to single limbs, generally affects multiple muscles. The initial TeNT neuroparalytic activity can be detected by measuring the compound muscle action potential, providing a very early diagnosis and therapy, thus preventing the ensuing life-threatening generalized tetanus.

Tetanus in a rural setting of South-Western Nigeria: a ten-year retrospective study

We review the records of 79 tetanus patients in two hospitals (one tertiary and one secondary level) in Owo, Ondo state, Nigeria from 1997 to 2006. The male: female ratio was 3:1. Ages were 14–70 years (mean 33.25 years, SD ±16.76). The overall case fatality rate (CFR), 32.91%, did was not significantly different in the two hospitals. CFR for men was 32.10% and for women 35.29%. The main factor indicative of bad prognosis was a short hospitalization period. It was observed that 30.38% of our patients were discharged against medical advice (DAMA), that financial constraint was the underlying problem in 50% of cases, and that the trend of DAMA occurred at the two study sites. This DAMA phenomenon could pose a great danger to the eradication of this vaccine preventable disease in rural areas.

Ketamine in the management of generalised cephalic tetanus

BACKGROUND

Tetanus is a fatal infection caused by the neurotoxin tetanospasmin released by the vegetative spores of Clostridium tetani. The high mortality rate is related to frequent tetanic fits with laryngeal spasm and airway obstruction. Numerous anticonvulsants are in use, with varying efficacy in controlling fits. This case report highlights the use of ketamine as adjunctive therapy in the management of tetanus.

CASE REPORT

A 20-year-old woman was admitted with a history of recurrent left ear pain, with bloody, purulent discharge, following a self-inflicted injury. She developed tetanic spasms 24 hours after admission. She had received no immunisations. A tracheostomy was established to relieve airway obstruction, and ketamine was added to the medication when breakthrough seizures were refractory to diazepam.

CONCLUSION

Ketamine is of proven safety as an anaesthetic agent, especially in cases in which an anaesthetist is not readily available. Its effectiveness in this case, in combination with diazepam, warrants further evaluation.

An Unusual Cause of ‘Ptosis’

A 29-year-old man with a history of dental restoration procedure was referred for a left Bell's palsy. At the emergency department, he complained instead of deteriorating unilateral ptosis and dysphagia. Incidentally, trismus was also noted. He was diagnosed with cephalic tetanus, which rapidly progressed to generalized tetanus. Ptosis is an unusual presenting complaint of tetanus. In this case, we attempt to explain how facial weakness, ptosis, and cephalic tetanus are all related. We also highlight the key aspects of tetanus in relation to the emergency physician.

Urinary catecholamine excretion in tetanus

Imperfect understanding of the pathophysiology of tetanus has limited therapeutic advances. Autonomic disturbance is a major cause of mortality and is believed to be associated with catecholamine release, predominantly norepinephrine. We measured epinephrine and norepinephrine concentrations in 24-h urine collections from tetanus and critically ill patients suffering from other severe diseases. In patients with severe tetanus, mean (SD) epinephrine was 164.18 (129.37) nmol x day(-1) compared with 45.18 (37.74) nmol x day(-1) in mild-moderate disease (p = 0.008). In the severe group, mean (SD) norepinephrine was 411.64 (208.5), and 121.00 (81.81) nmol x day(-1) in moderately ill patients (p < 0.001). Compared with critically ill control patients, median epinephrine was 331.77 in tetanus patients and 89.70 nmol x day(-1) in controls (p < 0.001). Median norepinephrine concentration was 788.02 nmol x day(-1) in tetanus and 300.05 nmol x day(-1) in control patients, p = 0.006. The study finds a novel result of increased epinephrine excretion in tetanus and confirms that catecholamine excretion in tetanus exceeds that in other critically ill patients. These results should be considered in designing more effective therapeutic strategies.