Leprosy

by G. Armauer Hansen; Carl Looft

The peripheral nerves were probably examined in all cases, but only the results of a few of the examinations are noted.

The lungs were found tubercular thirteen times, the intestine four times, once without the presence of pulmonary tuberculosis being noted, this making fourteen cases of tuberculosis out of thirty-six—almost exactly 39 per cent. In the nodular form we had thirty-six undoubted tubercular cases out of eighty-nine—rather over 40 per cent. Possibly, and indeed probably, some insufficiently described cases in this form were also tubercular, but the frequency of tuberculosis is so nearly equal in both forms, that there is no ground for supposing that the particular form of leprosy has any relation to the development of tuberculosis. Under precisely similar conditions, in our institution, the nodular and maculo-anæsthetic cases were pretty equally attacked by tubercle. If Leloir means to say that tuberculosis is much rarer in the maculo-anæsthetic form, than in the nodular, it is certainly not the case in our leper hospitals.

So far as concerns the necrosis of the bones, the panaritii and periostitides, we have found in them nothing specific; we have often sought for bacilli, but always in vain. Pyogenic cocci, usually the staphylococcus aureus, we have found both microscopically and in cultivations.

The mutilation of the bones may occur from concentric atrophy alone, as demonstrated by Prof. Hjalmar Heiberg (Klinisk arbog, III). The phalanges of the hands and feet, the bones of the metacarpus and metatarsus, and even the carpal and tarsal bones, diminish in all their dimensions, evidently from trophic changes, the result of the neuritis.

We have been able to examine anatomically a few of the cases of articular affection referred to above, but we have not seen instances of the acute affections on the post mortem table. R. Thoma has described clinically and anatomically a case of lepra tuberosa (Virchow’s Archiv, Bd. 57), in which first the elbow, and later the knee joint, was affected. Examination of the knee joint showed an inflammatory irritation of the nature of hæmorrhagic gonitis. Where we have noted joint affections in the maculo-anæsthetic form we have only noted a condition of hydrops. The chronic affections we may indicate as tubercular and tropho-anatomical. Tuberculosis attacks the joints of lepers by no means infrequently, as is easily explainable in the case of those already tubercular, by the frequent traumata to which the anæsthetic and paretic lepers are exposed. The carpal and tarsal joints are most frequently affected; but we have also seen the knee and elbow tubercular. The process is exactly the same, as in those who are not lepers. Chronic trophic joint affections are by no means so rare as was formerly believed. Prof. H. Heiberg has (loc. cit.) drawn attention to this, and has described a foot which resembles that described by Charcot as pied tabétique. According to Heiberg a characteristic of these leprous tropho-neurotic joint affections is swelling and laxness of the capsule of the joint, a wearing away and atrophy of the ends of the bones, or periostitis ossificans, and hypertrophy of the ends of the bones, which is especially seen in the tarsal and metatarsal joints. We have been able to confirm these results of Heiberg’s, and have also seen in such an ankle, growth of the synovial membrane with villous projections; the capsule of the ankle joint was loose and lax, the talus smooth and oblique, the cartilage worn away; and marked outward subluxation of the foot was present. Other older spirit preparations showed changes in the joint capsule, which was flabby and loose or thickened, and further, slight irregular thickening of the synovial membrane, and thickening of the ends of the bones.

We have also in some cases examined the tendon sheaths; but never, even when contraction had existed for a long time did we find any anatomical changes, which pointed to a tendo-vaginitis. Leloir and Wolff have noted this clinically, but we have been unable to confirm their observation.

The pemphigoid bullæ we have repeatedly examined, and never found lepra bacilli in their contents; both microscopically and on culture we have found only pyogenic cocci, usually the staphylococcus aureus. Müller found (according to Neisser, Virchow’s Archiv, Bd. 103) lepra bacilli in the contents of a pemphigoid bulla. This was probably a mere accident. For other morbid changes found in maculo-anæsthetic leprosy the reader is referred to [Table I], page 128.

Maculo-anæsthetic leprosy is therefore characterized by an infection of the skin and nerves directly caused by the lepra bacillus, and by secondary tropho-neurotic affections of the muscles, bones, and joints, the skin and organa sensus.

As is clear from the description of the two forms, the leprosy bacillus is found in the leprous products in both, though in much greater quantity in the nodular than in the maculo-anæsthetic form. The course of the two differs; in that in the nodular form eruptions constantly recur, and thus the affected areas are much more numerous than in the maculo-anæsthetic. Whether the liver, spleen, and testicle are attacked in the latter form we cannot as yet say with certainty. In one case of maculo-anæsthetic leprosy, we noted an affection of the throat exactly corresponding to that constantly present in the nodular form, and in another we found the inguinal glands affected with leprosy in a manner similar to that in the nodular form. In the maculo-anæsthetic form eruptions are also present, but they are by no means so frequent or so severe as in the other. Both forms may recover. As we have frequently noted in the description of nodular leprosy, the bacilli in the leprous products break up into granules which finally disappear, and there remains of the leprous products only a scar in which nothing leprous can be recognised. Occasionally this takes place in all the affected parts, and there remains only a widespread anæsthesia, the result of the nerve affections; and in the maculo-anæsthetic form this is the regular termination of the disease. In both cases the leprosy is completely healed.

We are thus enabled to see how complete is the parallel between the two forms. The course of the disease, especially the eruption, gives to it evidently the character of an infectious disease. In the nodular form, where the bacilli are present in millions or milliards, the eruptions or auto-infections are frequent; in the maculo-anæsthetic form, where their number is comparatively insignificant the eruptions are rare.