DISORDERS OF UPPER RESPIRATORY TRACT:

Common Cold:

It is most frequent and most common infection in infants  and children. Common cold corresponds  to  acute nasopharyngitis or influenza syndrome and may include systemic  febrile illness. 

Etiology

It  is usually caused by viruses viz. Andenovirus, rhinovirus, influenza virus, parainfluenza and respiratory  syncytial  virus. 

These are spread by droplet infection. 

Predisposing, Factors 

Chilling, exposure,  sudden  changes of  temperature,  overcrowding, poor sanitation ad  malnutrition predispose  to common cold. 

Pathogenesis 

The viruses,  first invade  the surface ciliated andnon-ciliated  epithelial  cells resulting in congestion and shedding of  the cilia  followed by invasion of deeper epithelial cells. This leads  to denudation of the mucosa and edema of subepithelial  tissue resulting  in congestion. Initially upper respiratory tract cells are affected but as disease  progresses  lower respiratory tract is also  involved. 

Clinical Features

Initially  there  is  irritation  and  feeling ofnasal  congestion - Sneezing - Nasal discharge initially watery and eventually becomes mucoid or purulent - fever and rigor Medical Management - No Antibiotics  are given unless  there  is secondary bacterial infection - Synptomatic treatment is given with analagesics,  decongestants, antihistamines  et