AGf~ICULTURAL RESEARCH, PUSA.

TIlE LEPROSY BACILLUS 207
characteristic trophic changes (c./!. anacsthetic skin
areas-" maculae "). Buth types of the disease Itlay
occur in the same paticnt.
The organisms are found in the granulomatous
lesions, being particularly nllmerons in the nodular
form. 'Thev are distributed intl-aeellnlm,Jy COl' the most
part, parallel hacilli occurring in bundles which may
completely fill up cells. 1'hey may be found also in
the t.issue spaces, in t.he walls of small vessels, in skin
glands, lymph glands, and in the sccretions of the
nose, throat and mouth, duc to t.he fact that thc
mucosal lesions ulcerate readily and discharge bacilli
into the mucous secretions. The organisms do not
occur in thc maculae which are essentially t.rophic
and not primary leprous lesions. In leprosy the
bacilli have actually been observcd in organs without
associated lesions.
The bacilli are present in the nerve granulomata
but are less numerous than in the nodular lesions.
DIAGNOSIS
Films arc made from any ulcerated nodule on the
skin, Or a non-ulcerated nodule can be punctured
with a needle and squeezed till lymph exudes, from
which films are made. Films can be prepared also
from a scraping of an excised piece of tissue, or sections
may be prepared as for histological examination. A
convenient mcthod is to remove with curved scissors
a pieec of skin (about 2 mm. deep) ovel-lying a nOllule
and pl'epare films from the deep surface.
The films or scctions are stain cd by the Ziehl­
Neclsell method, substituting 5 per cent. slllphuric aeid
for 20 per cent. The presence of the characteristic
acid-fast bacilli, especially when they occur in large '
numbers and are situated inside cells, is diagnostic.
As a routine measurc, films shou1c1 be made in 0.11
cascs from the nasal mucosa or s(,Cl'ctioll, as diagnostic
information may be obtained in this way even when
nodules are not present in the skin. This also applies
to t.he maculo-anaesthetic cases.