Internal Medicine

P1: RLJ/OZN P2: KUF

0521779407-D-01 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 7:41

488 Diphtheria

uncommon; neuropathy develops weeks to months after onset

of respiratory disease

➣Cardiac – wide spectrum of disease from ST abnormalities to con-

duction defects, including complete heart block, to arrhythmias;

usually occurs within several days to several weeks of onset of

respiratory disease

tests

■Diagnosis should be considered whenever a membrane is present

in association with upper respiratory signs and symptoms, but diag-

nosis confirmed by culturing C. diphtheriae from appropriate spec-

imens.

■Special medium (Loffler or Tindale) required for culture; if diagnosis

considered, notify laboratory so specimen can be plated on appro-

priate medium

■Confirm toxin production – Elek test (in vitro) or PCR in conjunction

with culture

differential diagnosis

■Group A streptococcal pharyngitis (also groups C and G), Arcano-

bacterium haemolyticum infection, viral pharyngitis, infectious

mononucleosis, epiglottitis

■Membranes usually not present in those diseases; when present, eas-

ily removed and not associated with bleeding of underlying mucosa

management

■If diagnosis considered, strict respiratory isolation required

■Careful monitoring in ICU for cardiac and respiratory complications

■Watch for superimposed bacterial pneumonia.

specific therapy

■Antitoxin – hyperimmune equine antitoxin given as soon as pre-

sumptive diagnosis made; dose depends on severity of disease

(details in package insert); skin testing required prior to adminis-

tration of full dose; if skin test positive, desensitization needed

■Penicillin or erythromycin is the drug of choice for total duration of

14 d; IV administration until patient can swallow, then oral medica-

tion to complete therapy

follow-up

■Patient should stay in isolation until therapy completed and should

have two negative cultures 24 h apart before isolation terminated.