Internal Medicine

0521779407-18 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 8:1

1260 Rabies

■Incubation period: variable, has been reported, however most occur

within 2 months after exposure

■Shorter incubation when bite on head vs. extremity

■Common in Asia/Africa/Latin America

Signs & Symptoms

Acute illness with rapidly progressive CNS systems; almost always pro-

gresses to coma and then death

■Initial neurologic signs may include hyperactivity, disorientation,

hallucinations, seizures, bizarre behavior, nuchal stiffness or paral-

ysis

■May have paresthesia/neuritic pain at site injury

■Other symptoms may include: fever, muscle fasciculations, hyper-

ventilation, hypersalivation, focal or generalized convulsions, and

priapism

■Some patients will complain of difficulty swallowing food and water

(hydrophobia)

■Waxing and waning neurologic status the first week of illness

■In 20% of cases: paralysis dominates clinical course (may look like

Guillain-Barre)

■Other organ failure commonly seen; renal and respiratory failure

■Coma usually occurs within 1 week onset neurologic symptoms

tests

Nonspecific:

■LP may be normal or show pleocytosis

■CSF pressure may be normal or elevated

Specific Tests:

Note: specimens should be from multiple sites. Consult with state

health department or CDC prior to obtaining specimens.

Ante-mortem Tests:

■Serology: IFA tests are available and should be performed, but note

that antibody does not appear until late in course, check serial sam-

ples in highly suspect cases

■Nuchal skin biopsy/saliva/CSF/cornea/skin; Rabies DFA is gold

standard and is usually available at State Health Departments (PCR

on these same specimens is sometimes used)

■Postmortem tests: Rabies DFA of brain stem, cerebellum and hip-

pocampus (PCR on these same specimens is sometimes used)