IV.—Leishmaniases

A. Kala-azar.

(i) “Indian” Kala-azar due to Leishmania donovani.

Indian kala-azar due to Leishmania donovani is a very fatal disease with a rate of mortality varying from 70 to 98 per cent. of the cases.

The incubation period is very variable and the early symptoms not well defined. The incubation period seems to range from three weeks to several months after exposure to infection. The onset seems to commence with a rigor and attack of irregular, remittent fever, which may show two remissions per day in a four-hourly temperature chart. Rogers considers the daily double remission almost diagnostic. The duration of this first attack is from two to six weeks. The spleen and liver enlarge, especially the former, and are painful and tender. Towards the end of the time the temperature declines and the first period of the disease ends. After this period an apyrexial interval occurs, which, after some weeks, ends in an attack of fever resembling the first. Periods of pyrexia and apyrexia alternate. Anæmia commences and asthenia appears and deepens steadily. The patient is now thin and wasted, the abdomen much swollen and protuberant, the ribs show clearly, the limbs are wasted and skin and tongue darker than normal. In Europeans the skin is of a remarkable earthy hue, and in natives of India darker than normal, approaching black. Intestinal disturbances, often in the form of very obstinate and intractable diarrhœa or dysenteric attacks, are common. Papular eruptions often appear, particularly on the thighs; hæmorrhages also may occur. The disease lasts for periods varying from seven months to two years, and usually ends fatally.

Treatment, unfortunately, has not been very successful up to 1915. Manson has reported two cases of cure by intramuscular injections of atoxyl daily or every other day in doses of 3 gr. Rogers has advocated large doses of quinine, 60 to 90 gr. daily until the temperature falls and then 20 gr. daily. Castellani and Chalmers consider the best results are obtained by large doses of quinine given intramuscularly, supplemented by a course of quinine cacodylate injections or atoxyl injections. Tartar emetic should be tried (see pp. , ), especially as L. Rogers (July, 1915) has had promising results in ten cases. Castellani (1914) and Mackie (1915), have also had successful results. Leishman states that the administration of red bone-marrow, either raw or in the form of tablets, may be beneficial. Good nursing and careful diet are essential, and diarrhœa or dysentery must receive the appropriate treatment.

With regard to preventive measures, the extermination of bugs and other biting insects seems to be of most service. Domestic and personal cleanliness is of great importance. Patients should be segregated. It would probably be as well if houses in which many cases of kala-azar occurred were destroyed. Dodds Price, in Assam tea gardens, moves the coolie lines 300 to 800 yards from old infected ones, with satisfactory results.

(ii) Infantile Kala-azar due to Leishmania infantum.

This malady is found among children, rarely in adults, along the Mediterranean littoral.

The disease commences insidiously and is often unrecognized until some intestinal disturbance occurs. The spleen is then found to be somewhat enlarged, and the case has often been regarded as one of malaria. The child becomes anæmic, suffers from diarrhœa, alternating with constipation, and has attacks of irregular fever. The spleen continues to enlarge and protrudes from under the cover of the ribs. Hæmorrhages from the nose and gums and into the skin occur. Anæmia and wasting set in. The abdomen then becomes very enlarged. The child becomes much less active both physically and mentally, and looks prematurely old. Death often occurs from exhaustion, though some cases of spontaneous recovery are known.

Treatment up till recently has been unsatisfactory. Some of the remedies tried, as quoted by Castellani and Chalmers, are 15 cg. doses of atoxyl, benzoate of mercury (2 to 4 mg. as a daily injection), thiarsol (5 to 15 mg. by subcutaneous injection), salvarsan, etc. Recently Cristina and Caronia (1915) have given repeated intravenous injections of 1 per cent. aqueous solution of tartar emetic, the dose varying from 2 to 10 cg. The treatment in various cases has lasted from 15 to 40 days.

Prophylactic measures seem to lie in the destruction of infected dogs and diminishing the breeding of fleas (see p. ).

B. Oriental Sore, due to Leishmania tropica.

Oriental sore, known under many other names (see p. ), is a local infection of the skin due to Leishmania tropica. The incubation period varies from a few days to some weeks, or even months, and then one or several small itching papules appear. Each spot becomes red and shotty, the papules increase slowly in size and the surface becomes covered with papery scales. After a variable time, usually not exceeding three to four months, ulceration occurs and a yellowish secretion is exuded that soon dries into a scab. Under the scab ulceration continues by erosion of the edges, and subsidiary sores arise around the parent ulcer and usually fuse with it. Healing commences after six to twelve months. Granulation begins at the centre and spreads outwards, and when healing is complete, a depressed, whitish or pinkish scar remains.

Many treatments for Oriental sore have been devised but do not seem particularly satisfactory. Castellani and Chalmers state that the scabs should be removed by boracic acid fomentations, and the ulcers thoroughly disinfected once or twice daily with a 1 per 1,000 solution of perchloride of mercury, after which an ordinary antiseptic ointment is applied.

The use of permanganate of potash has been advocated both by French and English doctors. Both large and small sores can be treated. The patient’s skin around the sore is protected by a thick layer of vaseline, and the surface of the ulcer powdered with potassium permanganate, which is kept in position by a pad of gauze and a bandage. The treatment is said to cause great pain for six to eight hours, but at the most, three treatments are necessary before the sore becomes a simple ulcer, well on the way to healing. The permanganate may also be used in ointment. Excision of the ulcer when small is advisable when the site of the ulcer permits of this. According to Manson, reports on treatment by radium, salvarsan and carbon dioxide snow are decidedly promising. Mitchell (1914) reports favourably on the use of carbon dioxide snow in the form of a pencil, in India. In Brazil several workers (1914) record successful results from the intravenous injection of a 1 per cent. solution of tartar emetic in distilled water. Low (1915) has successfully treated a case by direct local application of tartar emetic. Row (1912) has treated cases of Oriental sore by inoculation of killed cultures of the causal organism.

As the disease is very contagious, the slightest wound, and any insect bite, should be thoroughly disinfected with 5 per cent. carbolic acid or iodine. Destruction of bugs, lice, and other biting insects should be enforced. As dogs may contract the disease (see p. ), it is well not to allow them in the house and not to encourage undue contact with them.

Naso-oral Leishmaniasis (Espundia) due to Leishmania tropica.

This form of Leishmaniasis has been reported from South America and recently by Christopherson (1914) from the Sudan. In South America it is often called Espundia, also Buba and Forestal Leishmaniasis. The primary lesion is found usually on the forearms, legs, chest or trunk. This ulcer is of the Oriental sore type, and after some months, or even as long as two years, heals up, leaving a thick scar. While the ulcer is open, or more often after it has healed, lesions appear on the mucosa of the mouth and nose. The hard and soft palate, gums and lips all may be attacked. The mucosa of the nose is usually attacked and the cartilages become destroyed, producing great deformity. In bad cases the pharynx and larynx may become infected.

Till recently it was believed that treatment was of little use unless the case could be investigated early. Escomel considered that if the primary cutaneous lesion was excised or destroyed, further progress of the disease was prevented. When lesions have appeared on the mucosa of the mouth or nose, little could be done. The ulcers might be cauterized and mild antiseptic mouth washes used.

In 1913 Vianna, working in Brazil, introduced treatment by tartar emetic, which is now becoming more widely known and proving efficacious. Carini (1914) applies it thus. Tartar emetic (that is, potassium antimonyl tartrate) in 1 per cent. aqueous solution is introduced slowly into a vein, such as the vein at the bend of the elbow, in doses of 5 to 10 c.c. daily or on alternate days according to the tolerance of the patient to the drug. Eighteen to forty injections have been used. In some of the memoirs on the subject, the drug is referred to as antimony tartrate.

The course of the disease is chronic and may last for twenty to thirty years, death usually resulting from some intercurrent disease.

At present the actual transmitter of Espundia is not known with certainty. Various sand-flies (Simulidæ) have been suspected of transmitting the disease, though so far proof is wanting. It has also been suggested that the natural food sources of some Simulidæ known to bite man, namely, certain snakes and lizards, are possible reservoirs of the disease.

Prophylactic measures would seem to consist in the immediate disinfection of insect bites by tincture of iodine, and by avoidance of areas known to be infested with snakes and lizards, and insects that prey on them and man indifferently. The destruction of the primary lesion as soon as detected is essential, and the isolation of advanced cases of the disease seems advisable.