Classification of pulmonary tuberculosis with five digit code.

Many attempts have been made in the past to devise an accurate classification of the various types of pulmonary tuberculosis. It is particularly difficult for a classification to meet all the requirements of clinicians, anti-tuberculosis institutions, workers in vital statistics as well as those working in mass examinations of millions of apparently healthy people. Amongst all available classifications the best is the one compiled by Abbnecht-Fnaenkel later modified by Aschoff-Nicol. The last classification of the National Tuberculosis Association of America (1940) comprises the basic elements of the Aschoff-Nicol classification, such as the pathologic-anatomic form and clinical status of the disease. However, it has become apparent that this classification needs revision because it cannot comprehend certain types of pulmonary tuberculosis and give information as to relative infectivity. To meet the urgent demand for a universally acceptable system of classifying tubercubous disease of the lungs, Hllleboe and Holm’ devised a purely descriptive classification, which can be summarised in a simple four digit code. Ten selected findings for each of four categories have been arranged in a pattern. Each finding is assigned a digit form from 0 to 9 and as the order of the digit increases, the finding increases in seriousness. The code then is a four digit number, with the digit positioned so that the first digit always relates to the first category. (T) tubencle bacilli, the second to (C) cavities, the third to (L) lesions and the fourth to (F) principal symptoms. Comparison of four digit code for the same individual examined at different times, readily reveals progress of the disease, when the latest code contains digits that are higher than before. A patient’s improvement is reflected by a code with digits of a lower order. The classification of Hilleboe and Holm unquestionably gives accurate information as to relative infectivity and diagnosis of cavities and of principal symptoms. It is however, at a disadvantage since It gives no information as to the type of tuberculosis