Tetanus: pathophysiology, clinical signs, diagnosis, and update on new treatment modalities

Abstract

Objective: To review the pathophysiology, clinical signs, diagnosis, and current treatment modalities used in treating tetanus in small animals and humans. Etiology: Tetanus is caused by the activity of a toxin released from the bacterial organism, Clostridium tetani. The disease has an incubation period of 3 days to 3 weeks and usually follows a deep penetrating wound. Diagnosis: The diagnosis of tetanus is usually based on history and clinical signs. Therapy: Therapy of tetanus consists of direct and supportive care and includes toxin neutralization via human or equine derived immunoglobulin, antimicrobial therapy to eliminate C. tetani, and central and peripheral muscle relaxants to control hypertonicity. Adjunctive care may include positive pressure ventilation, anticonvulsant medication, drugs to treat autonomic dysfunction, and nutritional support. Prognosis: Prognosis varies based on severity of clinical signs at the time of diagnosis and the availability of appropriate care.

Magnesium sulfate as an adjunct therapy in the management of severe generalized tetanus in a dog

“…The dose of MgSO 4 (70 mg/kg over 30 min followed by an initial CRI of 100 mg/kg/d) for use in veterinary patients is extrapolated from human medicine and has been reported in a review on tetanus . Given the potential for magnesium toxicity, the starting dose in this case was considerably lower and consequently the time to achieve the desired target concentration was prolonged.…”

Diagnosis and treatment of generalised tetanus in dogs

“…Recovery of neuronal function requires regeneration of axon terminals, a process that may take two or three weeks (Linnenbrink and McMichael 2006, Adamantos and Boag 2007). …”

Administration of Biological Products

“…Additionally, disinhibition of the sympathetic nervous system and excessive catecholamine levels may result in tachycardia and hypertension. 60,61 Specific immunoglobulins that target tetanospasmin in the blood are a mainstay of therapy. Two products exist for treatment of tetanus in dogs, cats, and humans: equine antitetanus serum (ATS) (Professional Biological Company, Denver, CO) and human tetanus immune globulin (TIG) (Bayer Corporation, Elkhart, IN).…”

“…Two products exist for treatment of tetanus in dogs, cats, and humans: equine antitetanus serum (ATS) (Professional Biological Company, Denver, CO) and human tetanus immune globulin (TIG) (Bayer Corporation, Elkhart, IN). 61,62 As both are comprised of foreign proteins, hypersensitivity reactions are possible during and following administration.…”

“…However, intrathecal administration has been shown to increase morbidity and mortality in human patients and is not currently recommended. 61 Patients receiving antitoxin are monitored closely for signs of acute hypersensitivity, and emergency drugs (see Table 59.2) should be readily available. adamanteus envenomation has been reported.…”