Personal Medical Notes

1. Bacilli multiply locally, usually in throat, and elaborate powerful exotoxin which is
responsible for -
Formation of a false membrane over tonsils, pharynx and larynx. Membrane can’t be
wiped away.
Congestion, edema or local tissue destruction. Toxaemia. Enlargement of the regional
lymp node.
Fatality rate is 10%. In under 5 yr age, 20% fatality.
Agent
Caused by Corynebacterium diptheriae. Gram +, non- motile. No invasion power, but
produces exotoxin. Gravis infections tend to be more serious than mitis infections. Toxin
can affect the heart leading to myocarditis or the nerves leading to paralysis. Bacilli is
sensitive to penicillin and are readily killed by heat and chemical agents.
Souce of infection is a case or carrier. Carrier : Case ratio is 95 : 5. Immunization doesn’t
prevent the carrier state.
Infective materials are Nasopharyngeal secretions, skin lesion discharges, contaminated
fomites.
Period of infectivity is 14 to 28 days from the onset of disease.
Host
children aged 1 to 5.
Environment
all seasons, although winter months are favoured.
Transmission
droplet infections.
Incubation
2 to 6 days
Clinical features
Pharyngo-tonsilar diptheria – sore throat, difficulty in swallowing, and low grade fever
Laryngo-tracheal diptheria – fever, hoarseness and croupy cough, dyspnoea. Obstruction
may even cause suffocation if not promptly relieved by intubation or tracheostomy.
Nasal diptheria – localized to septum or turbinates of one side of nose.
Cutaneous diptheria is common in tropical regions. Lesions surrounded by erythema and
covered with a membrane.
Control
carriers can be detected early only by culture method. 2 consecutive nose and throat
swabs, taken 24 hr apart, should be negative before terminating isolation. Active
immunization with diptheria toxoid to all infants as early in life as possible, subsequent
booster every 10 yrs thereafter.
Treatment
diptheria antitoxin given IM or IV. Penicillin or erythromycin for 5-6 days to clear throat of
the bacteria.
DPT Vaccine
Should not be frozen. Stored b/w 2-8 ’C. Administered as early as 6 weeks after birth.

2. 3 doses, interval of 4 weeks b/w 3 doses. Booster at 18-24 months. Another booster (DT
only) at 5-6 yr of age.
Given in gluteal region. Especially for children under 1 yr of age, DPT should be
administered in lateral aspect of thigh.
Only such children who are seriously ill or need hospitalization are not vaccinated.