Points - Europe PMC

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Nov 28, 1987 - Dr ANNE MIER (Charing Cross and Westminster. Medical School,London W6 8RF) writes: Dr J Z. Heckmatt mentions that few young patients ...
BRITISH MEDICAL JOURNAL

VOLUME 295

Points Childhood immunisations in developing countries Drs SARA VARUGHESE (Ernakulam), JACOB M PULIYEL (Medical Trust Hospital, Cochin), and MATHEW M PULIYEL (Benzigen Hospital, Quilon 691 001, India) write: The role of BCG and its mechanism of action seem to be grossly misunderstood by Dr John D Holden (23 May, p 1329). In his model Dr Holden has assumed that BCG is effective in preventing tubercular meningitis and miliary tuberculosis. BCG has no part to play in preventing miliary tuberculosis. BCG at best sensitises the body to tubercular protein, perhaps simulating a primary infection.' Just as a primary infection cannot prevent reactivated tuberculosis, BCG vaccination cannot reduce the incidence of lung lesions which occur on inhaling the bacilli that cause tuberculosis; nor can it prevent these lesions from caseating or breaking into a blood vessel or miliary spread. BCG, however, helps by reducing the time lag between inhalation of the bacilli in a primary infection and the formation of the granulomatous reaction, which may otherwise take two to six weeks, during which time bacillaemia occurs. By reducing this bacillaemic phase BCG reduces the incidence of seeding foci and hence the incidence of brain, genitourinary, and bone tuberculosis. It cannot, however, prevent those cases of central nervous system tuberculosis that result from miliary spread of bacteria. 1 Puliyel JM. BCG vaccination. Indian Pediaur 1984;21:258.

Respiratory care in muscular dystrophy Dr ANNE MIER (Charing Cross and Westminster

Medical School, London W6 8RF) writes: Dr J Z Heckmatt mentions that few young patients can cooperate with the techniques of measurement of transdiaphragmatic pressure (24 October, p 1014). At Brompton Hospital we have assessed transdiaphragmatic pressure during the sniff manoeuvre in 61 patients whose ages varied from 12 to 74 years and found no lack of cooperation in the younger patients. As Dr Heckmatt points out, however, the postural fall in vital capacity does provide a simple and useful assessment of diaphragmatic function. When transdiaphragmatic pressure during a maximal sniff was related to the postural fall in vital capacity in the weak patients an inverse correlation was found (r= -0-63, p