Primary tuberculosis of the lung in children

Abstract

THE primary infection of the lung in childhood by the tubercle bacillus does not commonly give rise to any symptoms or signs, and the lesion produced passes from the first stage of initial reaction to the invading organism, through the healing process of resolution and organisation, to the final healed lesion without showing any evidence of its existence, except in the X-ray film. It is the complications and accidents occurring during the initial and healing stages which give rise to signs and symptoms and, in some cases, to death. Consequently, the picture produced by post-mortem examinations of the fatal cases or by clinical investigations of a sick child is apt to give a distorted picture of primary tuberculous lesions in childhood. It is only possible to study the pathology of simple primary lesions, therefore, in children who have died from some other cause. In I932 Blacklock ~ described the pr imary tuberculous lesions found in !,8oo consecutive autopsies performed on children. He was able from his findings to give a description of the pathological changes occurring during the initial stage and throughout the healing of such lesions. The earliest lesion in his series was found in a child aged seven weeks, but other workers have found lesions at a still earlier stage in younger children; Zarff records one in a child of twenty-four days. The earliest lesion described consisted of a localised broncho-pneumonic area in which the alveolar walls were swollen, the alveolar spaces containing fibrino-cellular exudate in which were many tubercle bacilli. Later there was evidence of necrosis and caseation in the pneumonic area with softening at the centre. At the periphery of the lesion tubercles with giant-cell