Typhus fever is a disease which tends markedly to affect the heart. Along with faint heart sounds we have a rapid, low tension pulse. In bacillary dysentery the tendency to an increase in pulse rate is of some value in differentiating it from amoebic dysentery.
African trypanosomiasis shows a rapid pulse rate whether the case shows temperature or not. In Brazilian trypanosomiasis the parasites may tend to invade the cells of the heart muscle thus producing manifestations of myocardial disease. The parasite (Schizotrypanum cruzi) may also affect the adrenals, causing a low blood pressure along with other signs of Addison’s disease.
The Respiratory System
Sputum Examination.—We should make a routine of examining a fresh specimen of sputum as well as stained smears. It is in such a specimen we search for the ova of the lung fluke.
Frequently the material submitted for examination as sputum is simply buccal or pharyngeal secretion, or more probably secretion from the nasopharynx, which has been secured by hawking. It should always be insisted upon that the sputum be raised by a true pulmonary coughing act, and not expelled with the hacking cough so frequently associated with an elongated uvula. When there is an effort to deceive, some information may be obtained from the watery, stringy mucoid character of the buccopharyngeal material and also from the presence of mosaic-like groups of flat epithelial cells (often packed with bacteria).
The pulmonary secretion is either frothy mucus or mucopurulent material, and if the cells are alveolar they greatly resemble the plasma cells. At times these cells may contain blood-pigment granules (heart-disease cells).
In the microscopic examination a small, cheesy particle, the size of a pin head, should be selected. This should be flattened out in a thin layer between the slide and cover-glass and should be examined for elastic tissue, heart-disease cells, eggs of animal parasites, amoebae, and fungi. Echinococcus hooklets, Curschman spirals besprinkled with Charcot-Leyden crystals, and haematoidin and fatty acid crystals may also be observed.
Curschman spirals indicate bronchial as against cardiac or uraemic asthma. Charcot-Leyden crystals have no special significance, except in certain tropical diseases when these crystals often are present in paragonomiasis sputum and in the pus of amoebic liver abscesses discharging by way of the lungs.
It may facilitate the examination of the sputum for elastic tissue and actinomycosis and other fungi to add 10% sodium hydrate to the preparation.