2. Diphtheria
An acute bacterial disease that can infect the body in two areas the
throat (respiratory diphtheria) and the skin (cutaneous diphtheria).
Etiologic Agent:
CORYNEBACTERIUM DIPHTHERIAE (Klebs Leoffler bacillus)
a toxin- producing organism; manufactures an exotoxin which is
responsible for major pathologic changes.
Gram positive non-sporulating, and generally aerobic.
3. the bacilli the superficial tissue with very limited extension beyond the
mucous membrane, but soluble toxin is capable of producing severe fatal
sequelae.
It is unstable and easily destroyed by light, heat and aging.
It is capable of damaging muscles, especially the cardiac, nerve kidneys,
the liver and other tissues.
Incubation period:
After being exposed to the bacterium, it usually takes 2 – 5 days for
symptoms to develop.
Period of Communicability
4. Variable; more than 2 – 4 weeks in untreated patients or 1 -2 days in
treated patients.
Source of infection:
Discharges from the nose, pharynx, eyes or lesions on other parts of the
body of infected persons.
Mode of Transmission:
Contact with patients or carrier, or with articles soiled with discharges
of infected persons.
5. Pathogenesis/ Pathology:
The toxin is absorbed into the mucous membrane and causes destruction
of the epithelium and superficial inflammatory response takes place.
Necrotic epithelium become embedded in exuding fibrin so that grayish
pseudomembrane is formed by leukocytes, fibrin and necrotic tissues and
microorganisms that adhere to the underlying tissues and leave a raw
bleeding when detached.
The larger the membrane, the more toxin are present in the blood stream and
in the tissues.
6. Commonly seen over the tonsils, pharynx or larynx, so that any
attempt to remove the pseudomembrane, exposes and tears the
capillaries, thus resulting in bleeding.
The bacilli within the membrane continue to produce toxins actively
that results in distant damage, particularly parenchymatous
degeneration, fatty infiltration and necrosis in the muscles of the heart,
liver, kidney, and adrenals, sometimes accompanied by gross
hemorrhage.
The toxins also produce nerve damage resulting in paralysis of the soft
palate, eye muscles or extremities.
7. Types:
1. Nasal – with serosanguinous secretions from the nose with foul smell.
2. Tonsilar-low fatality rate.
3. Nasopharyngeal – more severe type
Cervical lymph nodes are swollen
Neck tissues are edematous that result to the appearance of “Bull’s neck”
With marked degree of toxemia
Highest fatality rate
4. Wound or cutaneous diphtheria – affecting mucous membrane and any
break on the skin.
8.
9. Clinical Manifestations:
The onset of the disease is insidious with feeling of fatigue, malaise, slight sore
throat and elevation of temperature usually not exceeding 38 degrees Celsius.
Inflammatory reaction is initiated by the body and exudates consisting of
leukocytes, RBC, and necrotic tissues begin to form.
The exudates forming the membrane is grayish in appearance as it begin to form.
As it thickens, it becomes dull white.
Cervical adenitis with tenderness of the glands occur.
Body malaise, weakness, and apathy with rapid pulse rate that become
disproportionate to the low grade fever.
In severe cases, the entire neck become swollen with edema extending to the
chest.
The swelling of the neck has given the name “bull’s neck” form.
10. If the membrane forms in the larynx, it may extend to the trachea resulting in
respiratory problem which tracheotomy maybe necessary.
After administration of anti-toxin, the membrane begin to curl at the edges, begin
to separate and flakes off in large pieces.
Other common symptoms of respiratory diphtheria include:
Breathing difficulty
Husky voice
Increased heart rate
Stridor (a shrill breathing sound heard on inspiration)
Nasal drainage/secretions (serosanguinous with foul smell)
Swelling of the palate
Low grade fever
11. Symptoms of skin or cutaneous diphtheria are usually milder and may
include yellow spots or sores ( similar to impetigo) on the skin.
Complications :
Myocarditis caused by action of diphtheria toxin on the heart muscles.
Polyneuritis ; that include; paralysis of the soft palate, paralysis of the
ciliary muscles of the eye, pharynx, larynx, or extremities.
Airway obstruction may lead to death through asphyxiation.
12. Diagnostic Tests:
Swab from nose and throat or other suspected lesions
Virulence test
Schick test
Molony test
Loefler slant
Treatment Modalities:
Specific treatment of diphtheria is determined by the physician based on:
Overall health and medical history
Extent of the condition
Tolerance for specific medications, procedures and therapies
13. 1. Penicillin is usually effective in treating respiratory diphtheria before it
releases toxins in the blood.
2. Anti-toxin can be given in combination with penicillin.
Skin testing is necessary before the administration of anti-toxin.
3. Erythromycin 40 mg/kg 4 doses x 7-10 days.
4. Supportive therapy
Maintenance of adequate nutrition
Maintenance of adequate fluid and electrolyte balance
Bed rest
In presence of laryngeal obstruction, tracheostomy is usually done
14. Prevention:
Mandatory reporting cases.
Patients are isolated for minimum of fourteen days from the
onset of the disease until three cultures from the nose and throat
are reported negative.
Contact with children and food handling should be restricted
until bacteriologic examinations of cultures are reported negative.
Children under 5 years old should be given booster dose of
diphtheria tetanus vaccine.
Mandatory DPT immunization for babies.