PERTUSISS
Definition: -Highly infectious disease characterized by intense cough ,caused mostly by Bordetella Pertussis , which is a gram negative bacillus grown on Bordet –Genou media , only affecting humans . Transmission is by droplet infection especially during cough particularly during prodromal stage .
Pathology: -
Organisms adhere to the respiratory endothelial cells activating cytokines resulting in inflammation and necrosis of the cells and may be associated with bronchitis , atelectasis ,or bronchopneumonia .
clinical Features:-
Incubation period is 6 – 14 days, affecting children of all ages , being more serious but atypical in infants Under 6 months of age may present with cyanotic spells ,apnoea , cough but no whoop.Symptoms often last for 6 – 8 weeks ,and may be longer .It may be divided into 3 stages :
Catarrhal ( prodromal ,preparoxysmal ) last 1 – 2 weeks with rhinorrhoea , mild eye congestion , lacrimation mild cough , low grade fever ie. Upper respiratory tract infection like ,therefore diagnosis often missed .
Paroxysmal S. – 2 – 4 weeks ,increasing cough becoming paroxysmal followed by sudden inspiration with air inhaled forcibly against narrow glttis leading to a typical whoop .Often associated with cyanosis ,red face with petichiae and vomiting .Severe attacks may lead to anoxia , even brain damage as a result of encephalopathy .
Convalescent S. _1 – 2 weeks , decreasing frequency of paroxysms and that cough may persist for months and may recur during upper respiratory infections .D
Diagnosis:
Characteristic cough especially during outbreaks , exposure , inadequate immunisation .CBC – leukocytosis and lymphocytosis. Chest X – ray –perihilar infiltration , atelectasis ,or emphysema .Culture of nasopharyngeal secretions for BordetellaonBordet – Genou medium.
Differential Diagnosis – Paroxysms may be found in parainfluenza , adeno. Or other viral infections ,or foreign body
Complications:
1 – pneumonia
2-atelectasis
OM ,sinusitis
Hemorrhages :retinal , subconjungtival.
Inguinal hernia.
– convulsions or encephalopathy .
Treatment:
Erythromtsin given early on may reduce the shedding of the organism and may possibly ameliorate symptoms Azithromysin is preferedfor neonates Either may induce hypertrophic pyloric stenosis.
Prevention:
Acellular vaccine as part of DPT vaccine ,have less side effects ,give 70 – 90 % protection .give Erythromycin to contacts
IDEAL GROUP
A.H.Yahia