CHAPTER L. The Faeces and the Alimentary Tract in Tropical Diseases

THE FAECES AND THE ALIMENTARY TRACT IN TROPICAL DISEASES

THE FAECES

It is advisable to examine a stool macroscopically before taking up the microscopical examination. Pus or blood in stools may often be noted without the aid of the microscope.

The normal stool is sausage-shaped and soft.

The mucus of bacillary dysentery is opaque and grayish from the great number of pus and phagocytic cells. It is well to remember that Charcot-Leyden crystals, which are practically always absent from bacillary dysentery stools, are not infrequent findings in the amoebae-containing stools; of course, these crystals appear in other intestinal parasite infections.

In obstruction of the common bile duct we have acholic, whitish, foul-smelling stools. If the putty color be due to bacterial change exposure to the air will restore the brownish tinge.

Sprue stools are whitewash to putty-colored, pultaceous, and filled with air bubbles. The amount is excessive.

A very practical way of obtaining amoebae is to pass a rectal tube or a piece of drainage tube with fenestrations into the bowel, and amoebae may be found in the mucus filling the perforations in the tube.

Ordinarily the stool is best collected in quart fruit jars and examined as soon after evacuation as possible. The wooden spatula-like tongue depressors are well adapted for handling the specimen.

In examining a stool, it is well to color the drop of faeces, which is to be covered with the cover-glass, with a small loopful of ½% solution of neutral red. If diluting fluid is used, it should be salt solution, and not water. The neutral red tinges the granules of the endoplasm of amoebae and flagellates a very striking brown-red color, thus differentiating them from vegetable cells or body cells.

Encysted protozoa are difficult to diagnose, unless one possesses considerable experience. In examining for encysted amoebae as well as for bringing out the number of flagella of flagellates I now use the following method: Take a clean slide and make a vaseline line across it about 1 inch from the end. A drop of the iodine solution is placed on the slide about ½ inch from the vaselined line and a suitable portion of the faeces to be examined is emulsified in it. The edge of a square cover-glass is then applied to the vaselined line and allowed to drop on the preparation. By pressure suitable thicknesses of fluid can be examined. There is an absence of current motion.

Epithelial cells are generally more or less disintegrated. In the mucus of bacillary dysenteric stools, however, large intact phagocytic cells are frequent, which may be mistaken for encysted amoebae, and the polynuclear cell count averages 90% as contrasted with the average polynuclear count of 7.5% in amoebic dysentery.

When a smear preparation is desired, we may smear out a fragment of mucus and stain by Romanowsky’s or Gram’s method. Beautiful preparations may be made by mixing the faeces with water, then centrifuging for one minute. This throws down vegetable débris and crystals. Now decant the supernatant fluid, which holds the bacteria in suspension, and add an equal amount of alcohol. Again centrifuge, decant, and smear out and examine the bacterial sediment.

Simply taking a small mass of faeces and emulsifying it with a wooden toothpick on a concave slide in 70% alcohol—then, after the sediment settles, taking up a loopful with platinum loop from the surface and smearing out, gives a very satisfactory smear. Gram’s method, with dilute carbol fuchsin counterstaining, gives the best picture.

To culture for typhoid, dysentery, cholera, or other bacteria, take up the material in a tube of sterile bouillon and smear it out with a swab over a lactose litmus agar plate or an Endo or Conradi-Drigalski plate. Before streaking the plates they should be very dry on the surface. This can be best done by pouring the melted agar into a plate with a circular piece of filter-paper in the lid and placing in the incubator for one-half hour to dry. The filter-paper absorbs the moisture. Then inoculate the surface of the plate with the faecal material.

=Teague Medium.=—We have formerly preferred the Endo plate for typhoid work and the lactose litmus agar when culturing for dysentery bacilli. More recently we have obtained most satisfactory results with the Teague medium. The colon colonies, after eighteen hours, are deep black and opaque while the typhoid-dysentery group show colorless, transparent colonies.

The medium is prepared as follows: Nutrient agar is made in the usual way, containing 1.5% agar, 1% Witte’s peptone, 0.5% sodium chloride, and 0.5% Liebig’s meat extract, to the liter of distilled water. It is cleared with egg-white, placed in flasks, and sterilized in the Arnold sterilizer on three successive days. The reaction is brought to plus 0.8. The agar is melted and saccharose 0.5% and lactose 0.5% are added. The medium is then heated for ten minutes in the Arnold. To every 50 cc. of the medium are added 1 cc. of 2% yellowish eosin and 1 cc. of 0.5% methylene blue. The mixture is shaken and plates poured. Eosin solution should be added first.

=Occult Blood.=—In performing the test for occult blood, one should exclude the possibility of blood reaching the bowels from an extraneous source, such as ingested foods, mouth, nose, lungs and vagina, and the absence of interfering substances should be ensured. An absolute milk diet, or, at least, a diet containing neither meat nor green vegetables, is indicated for two or three days prior to the test, and all medication should be suspended. The technique noted on page 524 should be followed scrupulously when dealing with faeces.

It has been suggested that the absence of occult blood from the faeces may be accepted as an indication of cure in ancylostomiasis.

=Ova in Faeces.=—It is in the faeces we examine either for the parasites or for their ova in connection with practically all the flukes, except the lung fluke and the bladder fluke; for intestinal taeniases and for practically all the round-worms, except the filarial ones.

In the tropics, the examination of the faeces exceeds in value that of urine and is possibly more important than blood examinations.

=Helminthiasis Statistics.=—There is one point in connection with the statistical reports as to the presence of intestinal parasites in a given section of the tropics that I desire to emphasize.

Because a limited district shows a certain prevalence of intestinal parasites we should not conclude that the entire country from which such findings emanate shows a similar extent and type of infection. Take for instance the Philippine Islands.

In 1910, there were made in Cavite Province 932 stool examinations upon specimens from cases of sick people and of these only such patients as it was thought required such an examination for diagnostic reasons were made to bring such a specimen of faeces.

Of the 932 examinations, 135 or 14.4% failed to show the presence of intestinal parasites or their ova. The remaining positive examinations gave findings as follows:

-------------------+----------------------+--------------- Organism | Number of infections | Per cent. -------------------+----------------------+--------------- Ascaris | 627 | 67.2 Trichocephalus | 607 | 65.1 Flagellates | 135 | 14.4 Amoebae | 111 | 10.9 Hookworm | 23 | 2.4 Taenia saginata | 3 | 0.3 Balantidium | 1 | 0.1 Strongyloides | 1 | 0.1 -------------------+----------------------+---------------

At Bilibid Prison, Garrison encountered amoebic infection in 23% of the cases. In the medical survey of Taytay, his findings were 2.7%. Rissler and Gomez report only 0.39% of amoebic infection in their examinations in Las Piñas and no cases showing such infections in Tuguegarao and Santa Isabel. Such numbers are in striking contrast with those of former investigators, some of whom have reported as high a percentage of infection as 70.

Our findings as regards flagellates (14.4%) corresponded fairly closely with those of Garrison, namely, 21% at Bilibid and 5.5% at Taytay.

Garrison, for Trichocephalus infection, obtained 59% at Bilibid and 77% at Taytay; Rissler and Gomez give 53% at Las Piñas; 25.9% at Tuguegarao, and 6.23 at Santa Isabel. Our findings were 65.1%.

As regards Ascaris we found a higher rate of infection than for any other parasite (67.2%). Garrison encountered 26% at Bilibid and 82.9% at Taytay. The percentages of Rissler and Gomez are 77, 73, and 60 respectively for Las Piñas, Tuguegaroa, and Santa Isabel.

Garrison noted at Bilibid an incidence second only to Trichocephalus for hookworm infection, namely 52%. His percentage of infection at Taytay was 11.6. Rissler and Gomez found 11.14% of all cases examined infected with hookworms at Las Piñas, 8.01% in Tuguegarao, and 45.38% in Santa Isabel. We noted only 2.4% for Cavite, San Roque, and Caridad.

Our findings as regards Strongyloides (0.1%) were far below those reported by Garrison at Bilibid (3%) and at Taytay (0.7%). Rissler and Gomez found 2.24% infected in Las Piñas, but no cases were encountered in Tuguegarao and Santa Isabel. The same factors influencing hookworm infection in this locality may be operative for Strongyloides. Garrison found 0.2% of the individuals examined at Taytay to be infected with ciliates, while Gomez and Rissler failed to find such infections at Tuguegarao or Santa Isabel. We found a single case in the 932 examinations.

THE ALIMENTARY TRACT

The Mouth

In pellagra we have moist fissuring at the angles of the mouth with a large indented tongue with central coating and bare tip and sides. There is often a glairy mucus covering these red borders on the side. The fungiform papillae are prominent. Later on the tongue may become fissured and uniformly red. The buccal mucosa shows a carmine flush. The gums are tender but there is not the tendency to aphthous ulcers one sees in sprue. The flow of saliva is frequently increased.

In sprue there is at first great sensitiveness of the buccal mucosa so that articles of moderate pungency give rise to painful burning sensations. The tongue becomes quite sore with vesicle formation along borders and tip which soon turn into ulcers. Ulcerations also occur on the buccal mucosa, particularly at the site of the posterior upper and lower molar teeth (Crombie’s ulcer).

The congestion causes a great increase in mucus especially about the faucial pillars and pharynx. Ulcers are common about the fraenum of the tongue. While the tongue is coated at first with red ulcerated tip and sides it later becomes bare of any coating, red and finally even glazed as though varnished. It is at times fissured.

Onyalai.—A very peculiar disease of Portuguese West Africa and possibly the Soudan region, known as onyalai is characterized by the appearance of blood-distended vesicles of the mucosa of the cheeks and hard palate. The tongue is often swollen. The skin may show haemorrhages and haematuria is not infrequent. The mouth blebs vary in size from that of a split pea to a diameter of ½ inch or more. The cause is unknown.

Herpes labialis is not so common in tropical as in temperate climate malarias. It is absent in plague pneumonia.

In leprosy the nodules which form on the inside of the cheeks and fauces tend to show ulceration and thickenings. The discharges from the ulcerations in the nose, especially that on the vomer, reach the pharynx and such leprosy bacilli-containing discharges may be expectorated and cause one to consider the material as coming from the lungs.

In yellow fever the bleeding from the gums usually precedes the black vomit.

In kala-azar and possibly in malaria we may have gangrenous conditions of the cheek, as cancrum oris.

In the miliary type of verruga we may have the granulomatous lesions appearing on the mucous membranes of the mouth.

In typhus fever the mouth is strikingly foul with marked sordes covering the teeth. The dry brown tongue in this disease is known as the “parrot tongue.”

We may rarely have parotid gland enlargement in Malta fever, malaria and tsutsugamushi.

Parotitis is not uncommon in typhus fever. A type of parotitis which differs from mumps in not being contagious has been reported from the Philippines.

Stomach and Oesophagus

Very important in diagnosis is a tenderness in the pyloric end of the stomach, which is brought out by attempting to palpate the epigastric region. It is marked in yellow fever and acute pernicious beriberi as well as in blackwater fever and bilious remittent fever. We also frequently have epigastric tenderness, extending to the right, in ancylostomiasis.

Hookworms patients are often “pot-bellied” and the craving for eating unusual articles, as earth, may be connected with the gastric hyperacidity which the patient desired to neutralize with alkaline earth.

Sprue gives a flatulent dyspepsia with gaseous eructations.

Pellagra gives eructations and pyrosis and very common is a burning sensation going up from the stomach along the line of the oesophagus.

The esophagus is raw in sprue so that swallowing is painful.

Nausea and Vomiting

So many diseases are attended with nausea, besides those in which nausea is accompanied by rather constant vomiting, that it would hardly seem advisable to consider it alone. At the same time the slight nausea which often accompanies bacillary dysentery, as one of the manifestations of toxaemia, is of value in differentiating this type of dysentery from the amoebic one.

In yellow fever there may be early vomiting of whitish or bile-stained mucus but the well-known black vomit is a later feature, only occurring after the fourth day when the other haemorrhagic manifestations set in.

Bilious vomiting is the feature in bilious remittent fever which causes the patient the greatest distress.

In blackwater fever the frequent retching and bilious vomiting tend to exhaust the patient and the persistent vomiting of green bile often precedes death.

Bilious vomiting may be quite a feature of the icteric type of relapsing fever.

Vomiting sickness.—There is a disease known as vomiting sickness which has been noted in Jamaica. It occurs chiefly in children and has a sudden onset with marked vomiting followed by cerebral symptoms and great mortality. Some have thought the disease to be yellow fever but the fever and jaundice of that disease are absent. Scott has thought it to be epidemic cerebro-spinal meningitis, but more recently has suggested that it is possibly due to the eating of some poisonous substance, plant or otherwise, and that it is not an infectious disease. It is now recognized as due to ackee poisoning.

Vomiting is often a sign of dangerous vagal involvement in acute pernicious beriberi. Some consider that the extreme dilatation of the right heart, pressing on the stomach, may be the excitant of this vomiting.

The vomiting of cholera follows the diarrhoea. The material vomited may be of the same character as the rice-water stools.

In ptomaine poisoning vomiting precedes the diarrhoea.

Rarely a liver abscess may burst into the stomach, in which case we would have the vomiting of pus. Of course the more common route is by the lungs in which case the chocolate-colored liver abscess pus would be coughed up instead of vomited up.

The Intestinal Tract

It is usual to consider constipation as a clinical feature of such diseases as plague, yellow fever, Malta fever, beriberi and tsutsugamushi, as well as typhus fever.

Abdominal pains are most often connected with dysenteric conditions and it is customary to state that the greater the tormina, or intestinal griping, the nearer is the dysenteric process to the caecum.

In cholera the cramping of the abdominal muscles may follow that of the calf muscles.

In sprue we may have a doughy sensation on palpating the abdomen due to the fermenting contents of the intestine.

In the algid type of pernicious malaria the abdominal griping may be severe.

Tenesmus is the condition which along with tormina gives a diagnosis of some form of dysentery.

In rectal schistosomiasis the thickenings and blood extravasations, resulting from the eggs extruded by the fluke, may give rise to prolapse of the rectum. This may also occur in severe bacillary dysentery and in a disease of British Guiana and Venezuela, known as epidemic gangrenous rectitis, prolapse and gangrene of the rectum may occur. The symptoms are those of gangrenous dysentery.

Diarrhoea

The chronic diarrhoeas of the tropics are often associated with amoebic dysentery and in such cases we generally get a history of recurring attacks of diarrhoea separated by periods of constipation.

In sprue the condition generally sets in as a morning diarrhoea, very profuse and painless. Hill diarrhoea also shows frequent stools of whitish color from early morning until about noon.

The typical stool of sprue is a gas-permeated, putty-colored, offensive mass, extraordinarily copious.

In cholera the rice-water stool, which is not attended by pain, causes an unusual sense of prostration even at the onset of the stage of evacuation.

In pellagra we often have a recurring diarrhoea or mild manifestations of dysentery.

The stool of pellagra is darker and less copious than that of sprue and shows only a normal fat content while that of sprue is very fatty—as much as 30% of ingested fat appearing in the sprue stool as against the 5% for the normal one.

In Japanese schistosomiasis, following the stage of urticarial fever, we have our best diagnostic means in examining the blood-tinged bit of mucus capping the stool for the spineless ova of the fluke.

The fluke diseases of the liver and intestines give rise to various disturbances. The diagnosis is by the finding of the specific ova.

In infections with Strongyloides stercoralis there may be vague manifestations of neurasthenia and diarrhoeal disturbances. Cochin China diarrhoea was once thought to be a Strongyloides infection.

Infections with amoebae, intestinal flagellates and ciliates are discussed under dysentery.

Intestinal flagellates are so common in the stools of well people in the tropics that one should be very careful in assigning a pathogenic rôle to them.

It is now generally accepted that Lamblia (Giardia) can bring about exhausting diarrhoeas.

Intestinal Myiases

In the tropics vague intestinal disturbances or violent abdominal cramping may be brought about by dipterous larvae in the intestinal canal. The symptoms may be those of a dysentery and may be attended with fever and malaise. The biliary tract also may be invaded. For a more detailed statement of the several myiases, see Chapter XXV.

FIG. 159.—Larva of Anthomyia canicularis, enlarged. Rarely found in the stool. (Gould.) (From Tyson.)]

The larvae usually obtain access to the alimentary tract in food taken in by the mouth. Flies of the genus Sarcophaga are prone to deposit their larvae on food, especially meat that is somewhat tainted. Other flies, as Musca or Anthomyia, may lay their eggs on food. Flies of the genus Anthomyia tend to lay their eggs on plants.

It is possible for a fly to deposit its eggs or larvae about the anus while the man is at stool.

Great care must always be observed to assure one’s self that fly larvae, which may be present in the stool, have not originated from larvae deposited on the stool subsequent to its passage.

DETERMINATION OF DIPTEROUS LARVAE

There are certain points in the anatomy of dipterous larvae which must be considered in recognition of the genus or family of the flies concerned in the various myiases. The broad extremity is the posterior one and the tapering one the anterior. The dark hook-like processes, which may be in pairs or fused, project from the anterior or head end and above them is a pair of projecting papillae. The second segment from the head has on either side projecting hand or fan-like structures with varying numbers of terminal divisions, 4 to 40 or more. These are the anterior spiracles.

The large terminal segment has on its posterior surface two chitinized plates with 3 slits of various architecture in each. These are the posterior stigmal plates and are the structures we pay particular attention to in identification. In the early larval stages there is only one slit; in the second stage there are two. It is only in the fully developed larval stage that we note the characteristic 3 slit stigmal plates. The presence or absence of a rounded protuberance or button at the base of each stigmal plate should be looked for. The area carrying the stigmal plates may be sunken to form a pit. (See Fig. 135.)

KEY TO LARVAE OF THE MYIASES. (BANKS.)

1. Body with lateral and dorsal spinose processes Homalomyia. Body without such processes 2 2. Body ending in two fleshy processes; rather small species 3 Body truncate or broadly rounded at end 4 3. Processes bearing the stigmal plates; body about 5 mm. long Drosophila. Processes not bearing the stigmal plates; body 10 mm. or longer Piophila. 4. But one great hook; posterior stigmal plates with winding slits; no distinct lateral fusiform areas; tip of body with few if any conical processes Muscinae. With two great hooks; slits in the stigmal plate not sinuous 5 5. No tubercles about anal area; no distinct processes around stigmal field 6 Distinct tubercles above anal area; often processes around stigmal field; lateral fusiform areas usually distinct 7 6. Stigmal plates on black tubercles; lateral fusiform areas distinct Ortalidae. Stigmal plates barely if at all elevated; lateral fusiform areas indistinct; stigmal plates often contiguous or nearly so; slits long and subparallel Trypetidae. 7. Slits in stigmal plates rather short, and arranged radiately 8 Slits slender and subparallel to each other 9 8. Two tubercles above anal area; stigmal field with distinct processes around it Anthomviidae. Four or more tubercles above anal area; slits of stigmal plates usually pointed at one end Muscinae. 9. A button to each stigmal plate; slits rather transverse to body Calliphorinae. No button to stigmal plates, slits of one plate subparallel to those in opposite plate; plates at bottom of a pit Sarcophagidae.

A specimen of stool containing fly larvae may be incubated in a moist chamber in order to obtain the imago for species determination.