A CASE OF SPLENIC ABSCESS WITH ENTERIC FEVER
parations of nerve cells are difficult to obtain after fixation in Muller's fluid. The stains used were Nissl's toluidine blue, Giemsa, carmine, hsematoxylin, and Van Gieson, but the best results were obtained with Unna's polychrome methylene-blue, differentiating with alcohol and clove oil. Bielchowsky's silver method (Da Fano's modification) was tried, but owing to the fixation the intracellular neurofibrils did not take the stain. Nerve fibres were studied by the Marchi and Weigert-Pal
... d Weigert-Pal methods. The outstanding lesion is a generalised atrophy of the motor nerve cells of the spinal cord, the heaviest incidence having fallen in the cervical and upper dorsal regions. The anterior horn cells are much reduced in numbers. Those that remain are for the most part in various stages of chromatolysis, although a few, not more than two or three in most sections, appear normal. Even these seem, as a rule, smaller than the cells of a healthy child of the same age. In the degenerated cells the nuclei are pyknotic, the protoplasm vacuolated, and the Nissl granules powdery, irregularly distributed, and sometimes absent altogether. Similar changes are present in the anterior horn cells of the lumbar region, but they are not so severe and a larger proportion of normal cells remain. No obvious changes are present in the posterior horn cells. In the dorsal region a few of the cells of Clark's column and the intermediolateral tract are degenerated, but the majority remain intact. Higher up, in the brain-stem, the cell changes are not so marked. In the upper part of the medulla a few cells in the dorsal nucleus of the tenth and the nucleus of the eleventh i nerve are degenerated, but the damage is only slight. The most interesting lesion is met with in the oculomotor nucleus ' , at the level of the inferior corpora quadrigemina. The cells are not reduced in number, but about half of them show some degree of chromatolysis; in a few the Nissl granules have disappeared altogether. Higher up in the region of the anterior corpora quadrigemina the same nucleus shows practically no abnormality, only slight changes in one or two outlying cells being visible. In sections at this level the substantia nigra is seen to be very slightly affected and the cells of the red nucleus are normal. It is possible that the distribution of the lesion in the oculomotor nucleus explains the nystagmus which was observed clinically. The centre for lateral eye movements is partly degenerated, while that for up and down movement is intact. Weigert-Pal preparations show degeneration of a small area of white matter near the outer surface of the cord between the anterior and lateral columns at the point of issue of the anterior roots, at all levels of the cord. The anterior roots outside the cord are extremely atrophied. The posterior roots are normal. By the Marchi method very little degeneration, only confined to the cervical region, could be observed, most of the lesions being of too long standing to be detected by this method. In the medulla and mid-brain the only a,bnormality noticed was a very slight degeneration of the fibres of the twelfth nerve. The pyramidal tract was not completely myelinated, but the defect was slight and not more than might be accounted for by the child's age. The blood-vessels are everywhere very much engorged, but this is not unusual in cases of death from broncho-pneumonia. There is no perivascular infiltration. Neuroglial proliferation is not marked, and there is very little evidence of neuronophagia. Voluntary -muscles: Pieces of the sartorius muscle examined show advanced degeneration. The fibres are mostly extremely small, but vary very much in size. Longitudinal splitting has taken place, with the result that many sarcolemma sheaths are filled with numbers of minute fibres; in others, however, only proliferated nuclei are seen. Where splitting has not taken place the fibres for the most part appear homogeneous in substance and stain irregularly. One or two giant fibres are visible, but they are not as large as those which are seen in myopathy. Extensive fibrosis is present between the muscle fibres. Cross striation can be made out here and there, but is the exception rather than the rule. No interstitial or intracellular fatty change is seen in frozen sections stained with Scbarlach R. A few globules of fat are present round the vessels between the muscle bundles, but not more than occur normally.