Rabies

Rabies - Acute
Rahul Soman, M. Pharm

 

Definition  

Acute viral encephalomyelitis that develops following inoculation of rabies virus from either the saliva of a rabid animal in a bite wound or on mucous membranes or from inhalation of the aerosolized virus.

 

Medical History  

* Disorder related to transplantation

* Animal bite by potentially rabid animal

 

Findings  

* Coma

* Hematemesis

* Paralysis

* Respiratory distress

* Seizure

* Confusion

* Diplopia

* Dysphagia

* Excessive salivation

* Hallucinations

* Hyperactive behavior

* Hypotension

* Irritability

* Nuchal rigidity

* Nystagmus

* Pharyngeal spasm

* Rabies - hydrophobia

* Sinus tachycardia

* Strabismus

* Weakness of limb

* Animal bite - Acute

* Fever

* Headache

* Nausea and vomiting - Acute

* Paresthesia

 

Tests  

 

Suspected rabies  

* Cerebrospinal fluid examination: When considering a diagnosis of rabies, white blood cells may be present but are nondiagnostic; rabies antibodies, when present, are indicative of rabies infection.

 

Suspected rabies  

* Quantitative serology procedure: Serology testing for rabies can include an enzyme-linked immunosorbent assay (ELISA), a nucleic acid amplification assay, a polymerase chain reaction assay, and a fluorescent antibody test.

 

Suspected rabies  

* Open biopsy of lesion of brain tissue: Negri bodies are thought to be pathognomonic of rabies and represent the site of virus replication, although they may be absent in some cases .

 

Differential Diagnosis  

* Viral encephalitis - Acute

* Tetanus - Acute

* Delirium tremens

* Poliomyelitis, acute - Acute

* PHENOTHIAZINES

* Jakob-Creutzfeldt disease

* Pseudorabies

* Guillain-Barré syndrome - Acute

 

Treatment  

 

Drug Therapy  

 

 

Previously unvaccinated patients exposed to an animal suspected of having rabies  

 

RABIES IMMUNE GLOBULIN - RABIES VACCINE  

Adults: Rabies immune globulin 20 International Units/kg IM; infiltrate as much as possible of full dose around wound(s); give the remainder IM at anatomic site distant from vaccine administration AND rabies vaccine 1 mL IM in deltoid region as soon as possible after exposure; repeat rabies vaccine dose on days 3, 7, 14, and 28

Pediatrics: Rabies immune globulin 20 International Units/kg IM; infiltrate as much as possible of full dose around wound(s); give the remainder IM at an anatomic site distant from vaccine administration AND rabies vaccine 1 mL IM in lateral thigh as soon as possible after exposure; repeat rabies vaccine dose on days 3, 7, 14, and 28

 

 

Previously vaccinated patients exposed to animals suspected of having rabies  

 

RABIES VACCINE  

Adults: 1 mL IM in deltoid region as soon as possible after exposure; repeat dose 3 days later

Pediatrics: 1 mL in lateral thigh as soon as possible after exposure; repeat dose 3 days later

 

 

Preexposure prophylaxis for persons at risk for rabies exposure including veterinarians, animal handlers, certain laboratory workers, or international travelers who are in contact with animals where rabies is enzootic  

 

RABIES VACCINE  

Adults: 1 mL IM in deltoid region; repeat dose on days 7 and 21 or 28 after first dose

Pediatrics: 1 mL IM in deltoid region; repeat dose on days 7 and 21 or 28 after first dose; human diploid cell vaccine is the only rabies vaccine recommended by the CDC for pediatrics

 

Procedural Therapy  

 

Suspected rabies  

* Irrigation of wound: Wound cleansing is a highly effective component of rabies postexposure prophylaxis if done promptly .

 

Respiratory isolation as well as blood and bodily fluid precautions should be enforced in patients with suspected rabies.  

* Infection control procedure

 

An intravenous line should be started in patients with active rabies infection utilizing an 18 gauge catheter to provide access for fluids or medications.  

* Intravenous insertion

 

Dehydration  

* Intravenous fluid replacement: Intravenous fluid replacement is indicated for patients with dehydration when oral replacement cannot be accomplished .

 

Cerebral edema treatment modalities for patients with rabies who are in the coma phase may include head elevation, osmotic therapy, diuretics, rapid sequence intubation, barbiturates, hyperventilation, or mechanical decompression.  

* Management of increased intracranial pressure - Acute

 

Rabies  

* Continuous ECG monitoring: Bradycardia and sinus arrest are the most significant abnormalities associated with rabies infection. Arrythmias may be associated with episodes of hypoxemia.

 

Reportable infectious diseases  

* Infectious disease notification: In the United States, specific infectious diseases must be reported to the state or local public health department .

 

Respiratory distress  

* Airway management: Airway management must assume the first priority in the management of any seriously ill or injured patient .

 

Non-Procedural Therapy  

 

Attack by a rabid animal  

* Animal management