Monday, February 25, 2013

All You Need To Know About Whooping Cough (Pertusis)

Whooping-cough is an acute infectious disease with the droplet mechanism of transmission, is characterized by the cyclic prolonged duration and presence of paroxysmal cough attacks, absence of intoxication.

Etiology:  gram negative bacterium Bordetella pertussis

Humans are the sole reservoir of B. Pertussis (from the last days of the latent period up to 30 days, the disease has begun.
Infection is spread by way of droplets (droplet mechanism, air-droplet way of transmission) produced by the coughing of infected persons.
Pertussis is highly contagious. More than 90 % of susceptible house hold contacts become infected. More often occurs in infants (who were not vaccinated).

Entrance gate  is URT mucus membrane;
Due to several surface adhesions B. Pertussis attach to the respiratory epithelium of trachea;
colonization on a cylinder epithelium, toxin production;
local inflammatory processes, necrosis (catarrhal period);
The organism rarely invades tissues but produces the characteristic disease by Pertussis toxin systemic effects at distant sites in CNS (respiratory center, vascular center):
violation of breathing rhythm , hypoxemia, hypoxia;
vascular disorders + hypoxia = encephalopathy.
formation of stagnant excitation focus in the brain.
prolonged clinical disease.

Clinical presentation.
Incubation period typically is 7 to 10 days, but may be as short as 3 days, or as long as 20 days.
Catarrhal (prodromal) 7-14 days period: Whooping cough begins as an undifferentiated, typically subfebrile, upper respiratory tract infection with corryza and dry cough, more in the nighttime (with its gradual intensification). Toxic syndrome is absent.
Paroxysmal stage (4 -6 weeks) appears during the second week.
Paroxysmal cough should always alert the physical to the diagnosis. These paroxysms occur at variable intervals, and between episodes the patient usually appears comfortable, without signs of severe illness.
In young infants coughing may be accompanied by an inspiratory whoop. In the end of the cough – discharge much of transparent viscous phlegm. Vomiting, cyanosis, face swelling, apnea or respiratory arrest may complicate paroxysms of coughing. After severe paroxysms the patient may perspire profusely and appear exhausted. Subconjunctival hemorrhages, petechia, or epistaxis may result from severe spasmodic coughing.
The severing and frequency of these paroxysms of cough usually peak during the second or third week of the illness, but coughing can persist for 3 months or longer.
Hemorrhages in sclera, nose-bleeds, petechia on face are typical for this period.
Ulcer on the tongue frenula (Filatov’s sign) is Whooping cough characteristic sign.
Changes in other systems and organs: 
whooping cough lung (hard breathing, emphysema, intensification of pulmonary picture), bronchitis, bronchiolitis, pneumonia, athelectasis;
high blood pressure, tachycardia;
encephalopathy (anxiety or apathy, tremor, bad sleeping, seizures);
diarrhea (in infants).
Recovery period for 2 – 4 weeks
a cough loses spasmodic character, becomes easier, more rare;
vomiting disappears;
Asthenia for long period.

Typical Whooping cough severity

Prodromal period
9 – 14 days
6 – 9 days
3 – 5 days
4 – 5 weeks
5-6 weeks
6 – 8 weeks
Coughing number (per day)
Up to 15
16 - 25
> 25
Whoops number
3 – 5
> 10
Coughing number (between two woops)
3 – 5
6 – 9
10 – 12
Coughing paroxysm duration
Very long with vomiting, hemorrhages, urination or defecation in the end
May be present
General condition
disorders of sleep,
excitation, irritates
lowering of appetite, violation of sleep
Often repeating
In the rest


Perinasal, acrocyanosis
During cough
Faceeyelids after the paroxysm
Very often
Lungs symptoms
Emphysemasingle wheezes, rales
Emphysema, pneumonia
CNS symptoms

pneumonia (specific, caused by B.pertussis or secondary, caused by other bacteria);
hemorrhages into sclera, skin, brain, inner organs, nasal bleeding;
umbilical or inguinal hernia;
prolapsed rectum mucous membrane;
pneumomediastinum or pneumothorax;
ulcer under the tongue.

Peculiarities of the pertussis in young infants:
Incubation and catarrhal periods are shorter (few days).
Paroxysmal period is longer (60-90 days).
Whoops are absent.
Apnea occurs often.
Paroxysms of sneezing.
Often pneumonia, encephalopathy may develop.

Laboratory Tests
A culture of nasopharyngeal secretions for B. pertussis may confirm the diagnosis.
Direct fluorescent antibody staining of nasopharyngeal secretions.
Serologic tests (AR, PHAR): antibody to pertussis toxin measured by enzyme-linked immunosorbent assay.
WBC count may be elevated above 15 000/ mm3 with 70 % or more lymphocytes.
PCR positive for B. pertussis from the nasopharyngeal mucus.

Diagnosis example:
Whooping cough, typical form, paroxysmal period, severe degree, complicated by apnea and encephalopathy
Whooping cough, typical form, paroxysmal period, moderate degree, complicated by the leftside lobar pneumonia with cardiovascular syndrome, cardiac insufficiency 1st degree.
Whooping cough, typical form, catarrhal period

Differential diagnosis
Pertussis in catarrhal period may be confused with upper respiratory tract infections.
In paroxysmal period – with pneumonia caused by Chlamydia trachomatis, RS – virus, parapertussis.
In older children – with sinusitis, cystic fibrosis, aspirated foreign body, or tuberculosis.

Whooping Cough Differential Diagnosis

Whooping cough
(not complicated)
URT viral infection,bronchitis
Acute pneumonia
Cystic fibrosis
Subacute, acuteafter URT viral infection
slow (from the neonatal period)
Epidemiological history
Contact with patient who had the same disease
Contact with patient who had the same disease
Contact with patient who had the same disease
super cooling,
previous URT viral infection
Not complicated,
Complicated obstetric,
Genetic anamnesis
Main syndromes
Gradually intensified cough,that becomes paroxysmal,
Gradually intensifiedcatarrhal syndrome, rashes,intoxication
catarrhal syndrome, intoxication
Local changes in the lungs
Local, diffuse changes in the lungs,progressing respiratory insufficiency,intestinal problems,salt sweat
Cough character
Dry, moist
Increase, become paroxysmal
 With whoops
Dry, barking
Drymoist, barking in case of laryngitis
Dry or moist,
Toxic syndrome
Not typical
May be present
Not typical
Pulmonary percussion
Tympanic sound
(Tympanic sound in case of obstruction)
Local dullness
Local dullness (in case of exacerbation)
Pulmonary auscultation
Hard breathing
Hard breathing,wheezing
Hard breathing,wheezingmoist raleschange their localization after the cough
Local breathing weakening
Local small moist rales, crepitating, do not change their localization after the cough
Local breathing weakening
diffuse middle, small moist rales, stable changes
Respiratory insufficiency
In severe degree
Not typical
In case of obstruction
Expressed, progressing (in case of exacerbation)
Perinasal cyanosisfacial swelling
catarrhal syndrome, rashes appear on3 – 4th day,
catarrhal syndrome
In respiratoryinsufficiency –acrocyanosisin obstruction –involvement of intercostal spaces…
malnutrition,marasmus, chest deformationclubbing fingers
Dyspeptic sign
Vomit in the end of cough paroxysm
Not typical
May be in infants
May be in infants
greyointment-like, in large volume
Diagnosis substantiation
Positive throat culture
ELISA test,serology (CBR)
Virusological test from pharyngeal smears

If etiotrope therapy is begun in the catarrhal stage – the duration of illness is shortened. Etiotrope therapy is prescribed to all patients, if the disease duration is not longer than 3 wks.
The erythromycin regimen is 40-to-50 mg/kg/day in four divided doses (or another macrolides) for 14 days. If azythromycin is given its’ dose is 10 mg/kg/ for the 1st day, and 5 mg/kg/day for next days (the course is 5 days).
Alternative medicine (in case of hypersensitivity to macrolides) is trimethoprim/sulfomethoxasolum in average doses or ampicillin (100-200 mg/kg/day) for 14 days.
If the disease course is longer than 3 wks prescription of etiotrope therapy is discussed individually.

Pathogenetical therapy:
quiet and comfort; often ventilation, in mild and moderate cases – prolonged walks on fresh air
diet: usual daily food volume with increased numbers of feeding
therapy to decrease the cough center irritation (synecod)

In severe cases also:
therapy to decrease the cough center irritation (aminazin 1-2.5 mg/kg/day in 2-3 injections before going to sleep) or lytic suspension
novocain 0.25% 4 ml, +
aminazin 2.5% 1 ml, +
pipolphen 2.5% 1 ml (0.1 ml/kg of prepared solution).
intubation and ventilator support – in cause of apnea;
euphyllin 5-10 mg/ kg/day;
bronchial secretolytics (ambroxol, acetylcystein etc.), suctioning of secretions;
parenteral detoxication (5% glucose, physiologic sodium chloride solution);
Corticosteroids - 1-2 mg/kg/day prednisone or its equivalents for 3-5 days.

Isolation of the ill person on 30 days from the beginning of the disease.
Isolation of the contact persons younger 7 years old on 14 days.
Their throat culture (2 times), if negative – may attend preschool, school
Specific vaccination by DTP vaccine from 3 months of old 3 times with 30 days interval, revaccination in 18 months by DTaP vaccine.

1.     Current therapy in pediatric infectious diseases – 2 edited by John D. Nelson, M. D. – B.C. Decker  inc. Toronto, Philadelphia, 1988, - P. 134-138, 285.
2.     Ambulatory pediatric care (edited by Robert A. Derchewitz; - 2 nd ed. – Lippincot – Raven, 1992. – P. 570-574; 255.          
3.     Principles and Practice of Pediatric Infectious Diseases. / Edited by Saran S. Long, Larry K. Pickering, Charles G. Prober, PhiladelphiaPa: Churchill Livingstone; 1997. – 1921 p.

1.     Textbook of Pediatric Nursing.  Dorothy R. Marlow; R. N., Ed. D. –London, 1989.-661p.
2.     Pediatrics ( 2nd edition, editor – Paul H.Dworkin, M.D.) – 1992. – 550 pp.

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