Report on anaemia, or beri-beri, of Ceylon / by W.R. Kynsey.

  • Ceylon. Civil Medical Officer.
Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: Report on anaemia, or beri-beri, of Ceylon / by W.R. Kynsey. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    18/64 page 12
    worm forms its own cyst, whilst ia the case of other parasitic larvae (not always, however) the tissues of the host form the capsule. Tlie distension of the capsule takes place under the pressure of the fluid, which is invariably secreted within it. During the process of development the internal organisation of the parasite undergoes certain remarkable changes. These begin at the commencement of the intestinal tract, which changes into a slender, long oesophagus, a short, slender mouth-tube and a distinct bulging representing the stomach. The chitinous plates of tlie original stomach disappear completely. According to Perroncito, the position of the future armature of the mouth appears towards the end ot this period as brilhant little points. Further are noticed the throat papillae very distinct and large, occupying the same position as in the adult animal. The rudimentary genital organs appear in the usual position, and remain without undergoing any considerable further development. The exact observation of these changes was rendered very difficult by the fact that the parts were rendered turbid through the existence of granules inside the larva. Tlie one form passes into the other within a very short time, like dissolving views. Whilst these turbid granules are clearing away, or are being collected more regularly into groups, a new circumstance comes under survey, viz., the calcification of the capsule. Calcification of the Capsule.—This process, which seems essential for the development of the animal, commences by the appearance of clear shining points in the capsule, resembling somewhat globules of fat. These clear spots cannot be dissolved either by fluids which dissolve fat, or, at least in the beginning, by acids. The deposition takes place for a considerable time, longitudinally, in hues along the dorsal and abdominal surfaces, and seems formed by the apposition of minute rod-like plates. In course of time the whole capsule is converted into a rigid case, more or less homogeneous at the extremities, but otherwise forming a mosaic of granules and minute plates. (Perroncito attributes this as due to a disturbance of the deposited material by the movements of the animal.) Probably the newly-formed capsule is principally chitin ; at least it appears not only to resist physical influences, but also the efiects of alkalies, acids, and solutions of pepsin. Sooner or later, according to my observations, in the course of some months it is possible to dissolve the capsule by even a very dilute acid, and so set the animal free. Very often the latter appears shrunk and motionless in consequence, but it returns again to life on being put into warm water. (Perroncito.) I never succeeded in this myself, although I repeatedly tried the experiment. At other times, according to Perroncito, the animal is alive and active under the influence of warmth, but finally shrivels up and dies. The same happens when the capsule, either by accident or by the movements of its occupant, bursts, and the worm is set free. Very often the capsule is not dissolved, but becomes again quite hyaline, even in the case of larva over a year old. In this condition, the head-end of it is easily dissolved, and is often apparently burst open by the larva itself. Further Phases of Development.—As the encapsuled larvae are not yet in a fit condition to live at large, and besides are most active at the ordinary temperature of the human body, it is improbable that at this period they commence their parasitic life (as Perroncito believes;, judging from our experience of the Dochmius trigonocephalus, &c. Infection then might take place from the perfectly ripe calcified cyst being dissolved in the secretions of the stomach, and the worm being set free. The uncaicified cyst, on account of its insolubility, would not probably cause infection. At this point direct observation fails us, and we are left to mere hypothesis and analogies. Probably now the development and the differentiation of the sexes proceed at a rapid pace. In no case can the time exceed a few months, as I can assert from experience in the treatment of young children. According to Leuckart, Dochmius trigonocephalus is developed in three weeks. As to the place where this development occurs, we know nothing with certainty, as nowhere in the literature of this subject is mention made of a sexually mature larva. At all events, it seems striking, that such has never been noticed either on post-mortem examination or among the numerous parasites repeatedly expelled in the faeces. Among several thousands expelled during life, and examined most carefully by myself, I never observed a single worm sexually immature: even an apparently half-grown female of •7 mm. in length was sexually mature and already impregnated. It is true that a portion of the patients had been withdrawn for some time from the sources of infection, whilst others were always exposed ; but in no case was a sexually immature worm ever observed. Even supposing such lived at first in the stomach (as the Dochmius trigonocephalus, according to Leuckart), this would scarcely screen them from observation. On the other hand, if the development occurred outside the intestines, then their expulsion would be impossible. As a matter of fact, Griesinger and Bilharz have observed anchylostoma rolled up into a ball in cavities of the mucous membrane. There is no record of the stage of development of these, how- ever, but males and females were recognised, not whether they were sexually mature or nr»t. I quite concur with Leuckart, in opposition to other observers, including Perroncito, in supposing that this was a process of development, and not an error of observation. Still, the question is undetermined, and until it is determined in the case of man, the study of the Dochmius of the cat, likewise a blood-sucker, is recommended. My attempts to infect swine by various cultures and at difierent periods completely failed; nor could I discover parasites in swine from infected localities. I must therefore conclude that this worm is not, like several others, common to man and to swine. Leon Levaillaiit says he discovered it in a gibbon (? ape), otherwise its occurrence outside the human race is unknown. Experiments on monkeys would be of interest. Conditions of Development.—Ml&v having now studied the mode of development of the larva, we must examine the conditions under which this development takes place. [ 550 ]
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