Tuberculosis in Childhood:
Tuberculosis in childhood is a major health problem in Asian countries . The incidence of tuberculosis in children is quite high . If diagnosed in time and treated properly it can certainly improve the quality of life of the child . Diagnosis of childhood there is not a single test which can prove or disprove the diagnosis with 3. Overcrowding , lack of ventilation tuberculosis is quite difficult , because authority . Being a chronic disease the symptoms are vague and these symptoms are neglected by parents as well by the family physician .
Causative Agent : Mycobacterium tuberculosis .
The source of infection is an open case of tuberculosis in the family or neighborhood . The infected sputum spitted carelessly in open space by the open case of tuberculosis dries up and the bacilli are resuspended in the dust and air . This air acts as a source of infection for uninfected , susceptible children . The inhaled tuberculous bacilli may get lodged in pulmonary alveoli and the process of formation of primary focus starts .
Predisposing Factors for Tuberculosis in Childhood
1. Malnourished children are more susceptible to the disease .
2. Infections like measles , whooping cough increases the susceptibility
3. sunshine : These thing help in propagating the disease .
Pathogenesis of Tuberculosis in Childhood
Once the bacilli reach the alveoli through inhaled air the process of inflammation starts . Initially the polymorphs infiltrate at the site of lesion . This is followed by infiltration of lymphocytes because they have better phagocytosis function . Some of these lymphocytes join together to form epithelioid cells . Gradually the alveoli are filled with exudates containing fibrin material , tuberculous bacilli , lymphocytes , epithelioid cells and giant cells . The central portion of this exudates starts necrotizing , giving rise to caseous material .
The caseous material , surrounded by various types of cells is called as Primary focus . Some tubercle bacilli from primary focus traverse through lymphatic system to regional lymph nodes ( hilar ) . Same inflammatory reaction occurs in regional lymph nodes and they get enlarged . The primary focus , the draining Iym phatic system and the enlarged regional lymph nodes are collectively called as primary complex . The commonest site for primary complex is sub pleural re gion of right midzone and the lymphatic draining it to the right hilar lymph nodes .
Further course of primary complex will depend upon the resistance of the host .
1. If the host resistance is good the primary complex heals up by fibrosis and calcification without
leaving any radiological evidence .
2. If host resistance is poor following clinical presentation can occur .
a . The inflammatory process in primary complex starts spread ing in surrounding area giving rise to progressive primary complex . X – ray chest may show enlarged lymph node
b . The enlarged hilar lymph node may compress the surrounding bronchus and depending upon the degree of compression it may give rise to emphysema or collapse of lungs .
c .The caseous material of primary focus may liquefy to form cavity .
d . The enlarged lymph node may erode the bronchus giving rise to endobronchial tuberculosis
e . If resistance of the child is very poor caseous lymph node erode the blood vessels and large number of bacilli enter into the circulation causing miliary tuberculosis involving various organs .
f . In some children pleural effusion occurs as an allergic response to tuberculous proteins
The pathogenesis of tuberculosis is discussed in detail for 2 reasons:
1. Since it is a chronic disease any symptom involving respiratory system , if it doesn’t subside with routine line of treatment , possibility of tuberculosis should always be kept in mind .
2. Any + ve finding in chest X – ray – like enlarged hilar lymph node , cavity , collapse.
The child with tuberculous meningitis may present with fever , vomiting , altered sensorium and convulsions . chopneumonia , pleural effusion , possibility of tuberculosis should always be kept in mind and other necessary investigations to support the diagnosis should be carried out . Symptoms Incubation period varies from 4 to 8 weeks and symptoms start appearing after this . The common symptoms are- loss of appetite , low grade fever , failure to thrive , repeated attacks of cough and fever . Cough and fever not responding to the course of antibiotic . In children with poor socio – economical class these symptoms may go unnoticed by parents and suddenly child present with more severe form of tuberculosis like miliary tuberculosis and tuberculous meningitis .
Leave a Comment