1923- No. 16. THE NElROI.Or.ICAI. ASPECT OF lEPROSV. 75 



«ning of the nerves has been observed also in other forms of pol^'neuritis. 

 Thus it has been found by Bruusgaard and others in syphilitic neuritis. 

 Yet it is not at all a frequent occurrence in other forms of neuritis, and we 

 may regard thickening of the nerves as an important, if not infallable, indica- 

 cation of leprosy. The peculiar facial affection is another characteristic of 

 leprosy. True, the face may be aflected in other kinds of polyneuritis, as, e. g. 

 in bcri-heri; but in the latter disease the frequent affection of the pneumogastric, 

 the cardiac phenomena, above all the oedemata and the whole course of the 

 disease, make the distinction easy, quite apart from the fact that the facial paresis 

 never quite adopts the peculiar appearance of that in leprosy. The most 

 difficult form of neuritis to distinguish from leprosy is probablv the svphilitic. 

 The likeness which may sometimes exist between the cutaneous manifestation 

 of syphilis and leprosy enhances the difficulty. (Even Danielsen confesses to 

 having been unable to make the differential diagnosis between syphilis and 

 leprosy.) The chief points of distinction are the following. The syphilitic 

 polyneuritis generally shows a much quicker development, it has perhaps 

 a greater tendency to affect the deep sensation thus causing ataxia, it is 

 more often accompanied bv oculomotor and abducens paralysis (due in some 

 cases to a meningitis at the base of the brain), but is never accompanied 

 by the facial paralysis which is so characteristic of leprosy. The hypertro- 

 phic interstitial neuritis (Dèjêrine) may present points of likeness to the 

 neuritis of leprosy, in as much as the nerves may show considerable thick- 

 t-ning and may be distinctly palpable as in leprosy. There are however 

 several points of distinction : loss of joint sense and ataxic phenomena, and 

 also loss ot deep reflexes are frequent in this disease, but, as we have 

 seen, comparatively' rare in leprosy. To sum up, one may say that in no other 

 form of neuritis are the deep reflexes and the deep sensation so well pre- 

 served as in leprosy — and, on the other hand, no other form of neuritis 

 has the same tendency to involve the face as leprosy. On the whole I 

 feel inclined to regard the peculiar facial paralysis in leprosy as one of 

 the most characteristic manifestations of the disease. It cannot therefore be 

 emphasized sufficiendy how important the careful examination of all the 

 facial muscles is. 



Finally must be mentioned the diagnostic importance of the trophic 

 disturbances. In other forms of polineuritis pronounced trophic disturbances 

 like those found in leprosy are never seen. 



In svringomvelia and tabes one meets with neurotrophic osteopathic 

 and arthropathic disturbances which often affect bones and joints (e. g. elbow- 

 joint and knee-joint) which are practically never affected in leprosy. The 

 characteristic confinement to the most distal parts of the limbs, the peculiar 

 concentric atrophy, and the curious tenacity of the nails even in the most 

 extensivelv mutilated fingers and toes, are the most valuable points for 

 the diagnosis. 



