Visceral leishmaniasis (Kala Azar) is an infectious disease caused by a parasitic agent (Leishmania) that is widespread in tropical and subtropical regions. Depending on the pathogen subtype, visceral leishmaniasis can be severe.
What is visceral leishmaniasis?
Visceral leishmaniasis (Kala Azar) is an infectious disease that is rarely found in Germany and is due to the transmission of the parasitic infectious agent (Leishmania) by insects (butterfly mosquitoes, sand flies). For cephalhematoma explanation, please visit percomputer.com.
The causative agents of visceral leishmaniasis belong to the class of protozoa (animal protozoa), the so-called mastigophora (also: flagellate animals), which are widespread in Asia (particularly India), Africa, South America and the Mediterranean region. In most cases, those affected become infected with the pathogen during their trips to these countries.
While other forms of leishmaniasis affect the skin (cutaneous leishmaniasis) or skin and mucous membranes (mucocutaneous leishmaniasis), the most severe infection with Leishmania, visceral leishmaniasis, affects the internal organs, especially the spleen, liver, lymph nodes and bone marrow. In addition, skin changes in the form of dark spots can occur, from which the Indian expression for visceral leishmaniasis kala azar (“black skin”) is derived.
Visceral leishmaniasis is caused by a parasitic agent (Leishmania donovani, L. chagasi, L. infantum) belonging to the Mastigophora class. Infection with visceral leishmaniasis occurs via the bites of certain insect species (sand flies) that have previously infected infected vertebrates (mouse, wolf, dog).
After the insect bite, the Leishmania enter the monocyte-macrophage system, which cooperates with the lymphocytes to regulate the immune system and eliminates degradation and foreign substances, and multiply.
The monocyte-macrophage system includes the reticular connective tissue in lymphatic organs, the Kupffer stellate cells in the liver and histiocytes in the skin. These organ systems are correspondingly severely affected. In addition to indirect infection through insect bites, direct transmission through organ transplants and blood donations is possible.
Symptoms, Ailments & Signs
The symptoms of visceral leishmaniasis (kala azar) depend on the type of pathogen and how strong the immune system of the patient is. There are infections that are asymptomatic, but the disease usually affects the bone marrow, liver, spleen, or lymph nodes. The disease can either begin insidiously or break out suddenly, with the patient then suffering from a very strong feeling of illness.
Typical symptoms include swollen lymph nodes, weight loss, diarrhea and abdominal pain. Often the spleen and liver are also swollen, which can then be recognized by a bloated abdomen. There are also changes in the blood count. For example, those affected suffer from blood clotting disorders or anemia.
Skin changes are also common, with dark red papules or brown-black spots appearing. As the disease progresses, the skin then turns greyish. For this reason, visceral leishmaniasis is also called kala azar (“black skin”). After one to three years, those affected can develop what is known as post-kala azar skin leishmaniasis. Reddish or light spots then appear on the body or face, which then become lumps or papules and their appearance is also reminiscent of leprosy.
Diagnosis & History
Visceral leishmaniasis manifests itself after an incubation period of 10 days to 10 months (sometimes longer) with characteristic symptoms such as insidious or sudden onset of disease with weeks of remitting fever, abdominal pain, hepatosplenomegaly (enlarged liver and spleen), swelling of the lymph nodes, pronounced hypochromic anemia (hemoglobin deficiency ), thrombocytopenia (platelet deficiency) as well as dark, mottled skin pigmentation, amyloidosis (protein deposits) and cachexia (emaciation).
Visceral leishmaniasis is confirmed by detecting the pathogen in bone, spleen, liver or lymph node puncture. In the advanced stage of the disease, a puncture is no longer possible in some cases with visceral leishmaniasis, so that the diagnosis is secured using serological tests (immunofluorescence methods, ELISA technology). A leishmanin reaction test can be performed to determine the immune status of the affected person.
The course of visceral leishmaniasis depends to a large extent on the pathogen subtype. While Leishmania chagasi and Leishmania infantum often cause no symptoms and heal on their own, the often protracted infections with Leishmania donovani can be fatal if left untreated.
Those affected by kala azar suffer from various skin changes. These have a very negative effect on the aesthetics of those affected and can also lead to inferiority complexes or a significantly reduced self-esteem in the patient. In children, the disease can also trigger bullying or teasing.
Furthermore, Kala Azar leads to the formation of ulcers and further to a strong weight loss of the patient. Those affected sometimes suffer from diarrhea and vomiting and can also feel severe pain in the abdominal area. The affected person’s lymph nodes also swell and fever occurs.
The patients appear exhausted and tired and are therefore no longer able to carry out strenuous activities. As a rule, the disease has a negative effect on the life and everyday life of the person affected. In most cases, kala azar can be treated fairly well with medication.
There are no particular complications and the symptoms are significantly alleviated. In some cases, however, the drugs can cause side effects. With successful treatment, the patient’s life expectancy is not reduced.
When should you go to the doctor?
If health problems occur during a stay in Africa, South America or the area around the Mediterranean Sea, a doctor should be consulted. If the changes in health occur after a visit to the region there, the person concerned also needs a clarification of the complaints. In principle, however, it is important to find out about the local health conditions immediately before you start your journey.
It must be clarified which diseases are to be expected and how transmission can take place. If necessary, vaccinations are recommended. If swelling of the lymph glands, changes in the complexion or unwanted weight loss are noticed after an insect bite, there is a need for action. In the case of diarrhea, abdominal pain, nausea and a general feeling of illness, it is advisable to consult a doctor. The cause must be clarified and a diagnosis is necessary.
This is the only way to develop a treatment plan that can help alleviate the symptoms as quickly as possible. To avoid complications and minimize risks, it is necessary to consult a doctor if you feel unwell, develop lumps on the skin or discolouration. Inner weakness, circulatory disorders and an increased need for sleep are further signs of an existing illness. Since organic changes can occur in visceral leishmaniasis, you should react immediately at the first sign.
Treatment & Therapy
Visceral leishmaniasis is treated systemically with Ambisome (liposomal amphotericin B). Liposomal amphotericin B is well tolerated in most cases and is infused intravenously as part of a 10 to 20 day therapy.
In the case of intolerance or non-response to therapy with liposomal amphotericin, miltefosine and pentavalent antimony preparations are used as an alternative in visceral leishmaniasis. Miltefosine is given orally in tablet form twice a day for one month and causes only minor gastrointestinal distress (episodic diarrhea or vomiting ).
Pentavalent antimonies (sodium stibogluconate, meglumine antimonate), on the other hand, are injected intramuscularly or intravenously by the doctor as part of an average 28-day therapy in the hospital, whereby a longer-lasting dull pain at the injection site as well as nausea and headache can represent side effects.
In some cases, therapy with antimonene is ineffective in visceral leishmaniasis because the infectious agents have developed resistance to this drug. In addition, pentamidine and the antibiotic paromycin are used as antiprotozoal agents against visceral leishmaniasis.
However, pentamidine leads to pronounced side effects and affects, among other things, disorders of the glucose metabolism ( diabetes mellitus ) in more than 10 percent of those affected.
Since visceral leishmaniasis is transmitted to humans via insects, appropriate precautionary measures to protect against mosquito bites should be taken when traveling to areas such as Asia, primarily India, Africa, the Mediterranean region and South America. This includes wearing suitable long-sleeved clothing and using a close-meshed mosquito net while sleeping. So far there is no vaccination against visceral leishmaniasis.
Since visceral leishmaniasis affects the internal organs, successful treatment should always be accompanied by intensive follow-up treatment. The key here is the early detection and timely treatment of subsequent diseases of the organs. Accordingly, even after successfully treated visceral leishmaniasis, the organ values in the blood should be measured regularly.
In particular, the organs that were affected by visceral leishmaniasis should also be examined regularly using imaging methods (MRT, CT, X-ray, ultrasound) so that hidden organ damage that is not yet visible in the blood can be detected. If the skin was also affected by visceral leishmaniasis, the relevant areas must be examined regularly by a dermatologist, whereby tissue samples should be examined for the pathogen to be on the safe side.
In addition, persons previously suffering from visceral leishmaniasis should avoid traveling to areas (Asia) where the disease-carrying sand fly lives. If such trips cannot be avoided, intensive mosquito protection and skin hygiene must be ensured in order to avoid recurrence of visceral leishmaniasis. Mosquito nets should be very fine (1.2 millimeters) because the sand fly is very small. In addition, you should spray yourself several times a day with mosquito repellent sprays such as Autan (so-called repellents). In addition, you should shower every day. Face, neck and hands must also be covered with fabric if possible.
You can do that yourself
The drug therapy of visceral leishmaniasis can be supported by the patient’s own initiative. First of all, it is important to pay attention to typical side effects such as kidney pain or hypersensitivity disorders. If pain or other discomfort occurs, the doctor must be informed. After the intravenous treatment, bed rest is recommended in order to quickly recover from side effects such as headaches and body aches.
The cause of visceral leishmaniasis must be determined to avoid reinfection. Kala-azar is mostly transmitted by insects. A suitable insect repellent must therefore be used on future trips. Those affected should wear suitable clothing and sleep with a fly net at night. People who have already had kala azar are no longer allowed to donate blood. This safety precaution serves to prevent transmission of the pathogen to other people. The blood donation ban must be strictly adhered to, otherwise severe penalties are threatened.
Finally, after an illness, attention should be paid to unusual symptoms. In individual cases, the pathogen returns after months or even years and causes serious health problems. Comprehensive prophylaxis in the form of regular check-ups is therefore absolutely necessary.