Leishmaniasis
Disease Details
Family Health Simplified
- Description
- Leishmaniasis is a parasitic disease caused by Leishmania parasites and typically transmitted through the bites of infected female phlebotomine sandflies.
- Type
- Leishmaniasis is a parasitic disease caused by protozoa from the genus Leishmania. It is not genetically inherited but is transmitted through the bite of infected female phlebotomine sandflies.
- Signs And Symptoms
-
The symptoms of leishmaniasis are skin sores which erupt weeks to months after the person is bitten by infected sand flies.
Leishmaniasis may be divided into the following types:
Cutaneous leishmaniasis is the most common form, which causes an open sore at each bite site, which heals in a few months to a year and half, leaving an unpleasant-looking scar.Diffuse cutaneous leishmaniasis produces widespread skin lesions which resemble leprosy, and may not heal on their own.
Mucocutaneous leishmaniasis causes both skin and mucosal ulcers with damage primarily of the nose and mouth.
Visceral leishmaniasis or kala-azar ('black fever') is the most serious form, and is generally fatal if untreated. Other consequences, which can occur a few months to years after infection, include fever, damage to the spleen and liver, and anemia.Leishmaniasis is considered one of the classic causes of a markedly enlarged (and therefore palpable) spleen; the organ, which is not normally felt during examination of the abdomen, may even become larger than the liver in severe cases. - Prognosis
-
Leishmaniasis is a disease caused by protozoan parasites from the genus Leishmania. The prognosis for leishmaniasis varies depending on the form of the disease (cutaneous, mucocutaneous, or visceral), the species of Leishmania, the patient's overall health, and the timeliness and effectiveness of treatment.
- **Cutaneous Leishmaniasis:** Generally, the prognosis is good. Many lesions heal spontaneously over months to years, but they can leave scars. Early treatment can expedite healing and reduce scarring.
- **Mucocutaneous Leishmaniasis:** Prognosis is more guarded. This form can cause disfiguring damage if not treated promptly. Early and adequate treatment is essential to prevent severe tissue destruction.
- **Visceral Leishmaniasis (Kala-azar):** This form is more severe and potentially life-threatening if left untreated, with a mortality rate approaching 100% within two years. With appropriate and timely treatment, the prognosis is significantly improved, though it may leave the patient with chronic health issues.
Early diagnosis and prompt treatment are crucial for improving outcomes across all forms of leishmaniasis. - Onset
- Leishmaniasis onset typically varies depending on the form of the disease. For cutaneous leishmaniasis, symptoms can appear weeks to months after being bitten by an infected sandfly. For visceral leishmaniasis (kala-azar), the onset of symptoms can take several months to years after the bite. Symptoms may start with fever and progress to severe issues such as organ enlargement and weight loss.
- Prevalence
- Leishmaniasis is prevalent in tropical and subtropical regions across 88 countries. It mostly affects regions in the Americas, Asia, Africa, and the Mediterranean basin. It is estimated that 700,000 to 1 million new cases occur annually, with approximately 12 million people currently infected worldwide.
- Epidemiology
-
Out of 200 countries and territories reporting to WHO, 97 countries and territories are endemic for leishmaniasis. The settings in which leishmaniasis is found range from rainforests in Central and South America to deserts in western Asia and the Middle East. It affects as many as 12 million people worldwide, with 1.5–2.0 million new cases each year. The visceral form of leishmaniasis has an estimated incidence of 500,000 new
cases. In 2014, more than 90% of new cases reported to WHO occurred in six countries: Brazil, Ethiopia, India, Somalia, South Sudan and Sudan. As of 2010, it caused about 52,000 deaths, down from 87,000 in 1990. Different types of the disease occur in different regions of the world. Cutaneous disease is most common in Afghanistan, Algeria, Brazil, Colombia, and Iran, while mucocutaneous disease is most common in Bolivia, Brazil, and Peru, and visceral disease is most common in Bangladesh, Brazil, Ethiopia, India, and Sudan.Leishmaniasis is found through much of the Americas from northern Argentina to South Texas, though not in Uruguay or Chile, and has recently been shown to be spreading to North Texas and Oklahoma, and further expansion to the north may be facilitated by climate change as more habitat becomes suitable for vector and reservoir species for leishmaniasis. Leishmaniasis is also known as papalomoyo, papa lo moyo, úlcera de los chicleros, and chiclera in Latin America. During 2004, an estimated 3,400 troops from the Colombian army, operating in the jungles near the south of the country (in particular around the Meta and Guaviare departments), were infected with leishmaniasis. Allegedly, a contributing factor was that many of the affected soldiers did not use the officially provided insect repellent because of its disturbing odor. Nearly 13,000 cases of the disease were recorded in all of Colombia throughout 2004, and about 360 new instances of the disease among soldiers had been reported in February 2005.The disease is found across much of Asia, and in the Middle East. Within Afghanistan, leishmaniasis occurs commonly in Kabul, partly due to bad sanitation and waste left uncollected in streets, allowing parasite-spreading sand flies an environment they find favorable. In Kabul, the number of people infected was estimated to be at least 200,000, and in three other towns (Herat, Kandahar, and Mazar-i-Sharif) about 70,000 more occurred, according to WHO figures from 2002. Kabul is estimated as the largest center of cutaneous leishmaniasis in the world, with around 67,500 cases as of 2004. Africa, in particular the East and North, is also home to cases of leishmaniasis. Leishmaniasis is considered endemic also in some parts of southern parts of western Europe and spreading towards north in recent years. For example, an outbreak of cutaneous and visceral leishmaniasis was reported from Madrid, Spain, between 2010 and 2012.Leishmaniasis is mostly a disease of the developing world, and is rarely known in the developed world outside a small number of cases, mostly in instances where troops are stationed away from their home countries. Leishmaniasis has been reported by U.S. troops stationed in Saudi Arabia and Iraq since the Gulf War of 1990, including visceral leishmaniasis.
In September 2005, the disease was contracted by at least four Dutch marines who were stationed in Mazar-i-Sharif, Afghanistan, and subsequently repatriated for treatment. - Intractability
- Leishmaniasis is not generally considered intractable, as it is treatable with various medications. The treatment approach depends on the form of leishmaniasis (cutaneous, mucocutaneous, or visceral) and the specific species of Leishmania causing the infection. Common treatments include pentavalent antimonial compounds, amphotericin B, miltefosine, and paromomycin. However, treatment can be complicated due to factors such as drug resistance, side effects, and the need for prolonged therapy. Early diagnosis and appropriate medical intervention are crucial for effective management.
- Disease Severity
- Leishmaniasis is a disease with variable severity, ranging from mild cutaneous lesions to severe, potentially fatal visceral involvement. The clinical presentation depends on the Leishmania species and host factors. Mild forms typically manifest as skin sores, while more severe forms can cause extensive mucocutaneous damage or systemic issues affecting internal organs.
- Healthcare Professionals
- Disease Ontology ID - DOID:9065
- Pathophysiology
-
Leishmaniasis is a disease caused by protozoan parasites of the genus Leishmania. The pathophysiology involves several complex interactions between the parasite and the host's immune system.
1. **Transmission and Infection**: The disease is typically transmitted through the bite of infected female phlebotomine sandflies. When the sandfly bites, it injects promastigotes, the flagellated form of the parasite, into the host's skin.
2. **Cellular Invasion**: Promastigotes are phagocytized by macrophages and other phagocytic cells in the skin. Inside the host cells, they transform into amastigotes, the non-flagellated form.
3. **Intracellular Survival and Replication**: Amastigotes multiply within the phagolysosomes, which are specialized compartments inside the macrophages. They avoid destruction by modulating host cell signaling pathways and the immune response.
4. **Spread and Immune Response**: The infected macrophages can travel to various tissues, leading to different forms of the disease—cutaneous, mucocutaneous, or visceral leishmaniasis. The type and severity of the disease depend on the Leishmania species involved and the host's immune response.
The immune system's response to Leishmania involves both the innate and adaptive arms, but the parasite's ability to manipulate these defenses is key to its survival and pathogenicity. - Carrier Status
-
Carrier status: Leishmaniasis is not associated with a human carrier state. The disease is transmitted by the bite of infected female phlebotomine sandflies.
Nan: "Nan" typically refers to "not a number" or "not applicable." In the context of leishmaniasis, it suggests there is no numerical or directly relevant information regarding this aspect. - Mechanism
-
Leishmaniasis is caused by protozoan parasites of the genus Leishmania. The mechanism involves transmission through the bite of infected female phlebotomine sandflies. When the sandfly bites a host, it injects the promastigote form of the parasite into the skin. These promastigotes are then phagocytized by macrophages and other types of mononuclear phagocytic cells.
**Molecular Mechanisms:**
- **Entry and Survival:** Once inside the host macrophages, the promastigotes transform into amastigotes, which are the non-motile, intracellular form that thrives in the acidic environment of the phagolysosome.
- **Host Immune Evasion:** The parasites evade the host immune response through various mechanisms. They modulate the host's immune system to ensure their survival and replication. Leishmania parasites can inhibit the function of the phagosomes, preventing their maturation and fusion with lysosomes.
- **Modulation of Host Signaling Pathways:** The parasites affect various host cell signaling pathways. For example, Leishmania can manipulate the JAK/STAT and NF-κB pathways to suppress the production of pro-inflammatory cytokines, thereby dampening the immune response.
- **Protection Against Oxidative Stress:** Leishmania possesses mechanisms to detoxify reactive oxygen species produced by host macrophages. Enzymes like superoxide dismutase and trypanothione reductase play crucial roles in mitigating oxidative damage.
- **Manipulation of Apoptosis:** The parasite can also influence the apoptotic machinery of the host cells. By modulating the expression of pro- and anti-apoptotic factors, Leishmania ensures a conducive environment for its survival and replication within the host cells.
Understanding these molecular mechanisms is crucial for developing targeted therapies and effective vaccines against leishmaniasis. - Treatment
-
The treatment is determined by where the disease is acquired, the species of Leishmania, and the type of infection.
For visceral leishmaniasis in India, South America, and the Mediterranean, liposomal amphotericin B is the recommended treatment and is often used as a single dose. Rates of cure with a single dose of amphotericin have been reported as 95%. In India, almost all infections are resistant to pentavalent antimonials. In Africa, a combination of pentavalent antimonials and paromomycin is recommended. These, however, can have significant side effects. Miltefosine, an oral medication, is effective against both visceral and cutaneous leishmaniasis. Side effects are generally mild, though it can cause birth defects if taken within three months of getting pregnant. It does not appear to work for L. major or L. braziliensis.The evidence around the treatment of cutaneous leishmaniasis is poor. A number of topical treatments may be used for cutaneous leishmaniasis. Which treatments are effective depends on the strain, with topical paromomycin effective for L. major, L. tropica, L. mexicana, L. panamensis, and L. braziliensis. Pentamidine is effective for L. guyanensis. Oral fluconazole or itraconazole appears effective in L. major and L. tropica. There is limited evidence to support the use of heat therapy in cutaneous leishmaniasis as of 2015.There are no studies determining the effect of oral nutritional supplements on visceral leishmaniasis being treated with anti-leishmanial drug therapy. - Compassionate Use Treatment
-
Leishmaniasis is a parasitic disease caused by protozoa of the genus Leishmania. The treatment options often depend on the specific type of leishmaniasis (cutaneous, mucosal, or visceral) and the geographical region. Here’s information on compassionate use and off-label or experimental treatments:
### Compassionate Use Treatments:
- **Miltefosine**: While it is approved in some regions, it may be used compassionately in areas where it is not readily available. It is an oral medication effective against various forms of leishmaniasis.
### Off-Label or Experimental Treatments:
- **Amphotericin B (Liposomal form)**: Primarily used for visceral leishmaniasis; although officially approved, it is also used off-label for other forms of leishmaniasis.
- **Paromomycin**: An aminoglycoside antibiotic that is approved in certain countries but may be used off-label elsewhere.
- **Azithromycin**: This antibiotic has been explored for its anti-leishmanial properties, especially in cases resistant to conventional treatments.
- **Imiquimod**: A topical immune response modifier used experimentally for cutaneous leishmaniasis, often in combination with antimonial drugs.
- **Thermotherapy**: Involves the localized application of heat to lesions and has shown promise in experimental studies for cutaneous leishmaniasis.
These treatment options should be considered in consultation with a healthcare provider experienced in infectious diseases and the specific therapeutic context of each patient. - Lifestyle Recommendations
-
For leishmaniasis, the following lifestyle recommendations can help manage and prevent the disease:
1. **Prevent Sand Fly Bites**:
- Use insect repellent on exposed skin and clothing.
- Wear protective clothing such as long sleeves and pants, especially from dusk to dawn when sand flies are most active.
- Sleep in well-screened or air-conditioned rooms.
- Use bed nets treated with insecticides.
2. **Environmental Control**:
- Minimize the presence of sand flies by reducing breeding sites around living areas.
- Clear vegetation and organic waste near homes to reduce sand fly habitats.
- Use insecticides in areas where sand flies are prevalent.
3. **Personal Hygiene**:
- Maintain good personal hygiene to reduce the risk of secondary infections.
4. **Monitor Health**:
- Seek medical attention if you develop symptoms such as skin sores, fever, weight loss, or an enlarged spleen or liver.
- Adhere to prescribed treatment regimens if diagnosed with leishmaniasis.
5. **Community Involvement**:
- Engage in community efforts to control sand fly populations and educate others about prevention methods.
By following these recommendations, individuals can reduce the risk of contracting leishmaniasis and improve outcomes if they do become infected. - Medication
- Leishmaniasis is primarily treated with antimonial compounds, such as sodium stibogluconate or meglumine antimoniate. Other medications used include amphotericin B, miltefosine, and pentamidine. The specific treatment depends on the type of leishmaniasis (cutaneous, mucocutaneous, or visceral) and the geographic region where the infection was acquired. Always consult a healthcare professional for accurate diagnosis and treatment.
- Repurposable Drugs
- For leishmaniasis, some drugs that have been considered for repurposing include amphotericin B, miltefosine, pentamidine, and paromomycin. These drugs are primarily used for other indications but have shown effectiveness against different species of the Leishmania parasite. The abbreviation "nan" commonly stands for "not a number" in computing contexts, but if you meant something else, please provide additional details for clarification.
- Metabolites
-
Leishmaniasis is caused by protozoan parasites of the genus Leishmania. The metabolites associated with this disease can vary, but important ones include lipophosphoglycan (LPG), which plays a role in the parasite's virulence and ability to infect host cells. Additionally, amastigotes (the intracellular form of the parasite) produce metabolites like arginase, which helps them evade the host's immune response by modulating nitric oxide levels. Other metabolic products include various glycolipids and proteophosphoglycans, which are involved in the parasite's survival and pathogenicity.
The mention of "nan" (potentially referring to nanotechnology) suggests interest in how nanotechnology might be applied to leishmaniasis. Nanotechnology offers potential in diagnostics, treatment, and vaccine development for leishmaniasis. For instance, nanoparticles can be used to deliver drugs more effectively to infected cells or to create more efficient and targeted vaccines. Researchers are also exploring the use of nanomaterials for diagnostic purposes, aiming to detect Leishmania parasites with higher sensitivity and specificity.
Would you like detailed information on any specific aspect? - Nutraceuticals
-
Nutraceuticals, which are products derived from food sources that offer health benefits beyond basic nutrition, have gained interest in the treatment and management of leishmaniasis. Some studies have investigated natural compounds with potential anti-leishmanial properties, including curcumin, resveratrol, and various plant extracts rich in antioxidants and bioactive compounds. These nutraceuticals can help modulate the immune response and reduce inflammation, potentially complementing conventional therapies.
Regarding nanotechnology, nanomedicine approaches for leishmaniasis involve encapsulating anti-leishmanial drugs in nanoparticles to improve their efficacy, bioavailability, and targeted delivery. These nanoparticles can enhance the therapeutic index of drugs like amphotericin B, reducing toxicity and improving treatment outcomes by delivering the drug directly to infected cells. Liposomal formulations and other nanoparticle-based systems are being actively researched to optimize and develop better treatment strategies against leishmaniasis. - Peptides
-
Leishmaniasis is a disease caused by protozoan parasites from the genus Leishmania. The disease has various forms, including cutaneous, mucocutaneous, and visceral leishmaniasis.
**Peptides in leishmaniasis:**
- Peptides are being explored as potential therapeutic agents and vaccine candidates for leishmaniasis.
- Antimicrobial peptides can directly target Leishmania parasites.
- Synthetic peptides derived from Leishmania antigens have shown promise in inducing immune responses and could be used in vaccines.
**Nanotechnology in leishmaniasis:**
- Nanoparticles are being researched for drug delivery systems to enhance the efficacy and reduce the toxicity of anti-leishmanial drugs.
- Nanoformulations, like liposomes and polymeric nanoparticles, can improve the stability and bioavailability of drugs.
- Nanoparticles can also be designed to specifically target infected cells, increasing the precision of treatment.
Combining peptides and nanotechnology could offer innovative approaches for more effective treatments and vaccines against leishmaniasis.