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LEISHMANIASIS. Dr.Abdul latif Mahesar Dept.of medical pharmacology King Saud university. Pharma Team. Introductions. Leishmaniasis is a parasitic disease caused by microsopcopic protozoans of genus leishmania It was identified by a British medical officer Sir William Boog Leishman .
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LEISHMANIASIS Dr.AbdullatifMahesar Dept.of medical pharmacology King Saud university Pharma Team
Introductions • Leishmaniasis is a parasitic disease caused by microsopcopicprotozoans of genus leishmania • It was identified by a British medical officer Sir William BoogLeishman. • It occurs in the Mediterranean region, Africa , central and south America.
The parasite is in blood stream • It is transmitted from animals to humans and between humans by the bite of an infected sand fly. • It is diagnosed by the presence of parasite in biopsy from skin lesions • Its treatment is limited due to toxicities and failure of the drugs. • It can cause visceral disease mainly enlargement of liver and spleen with anemia and intermittent fever, as well as cutaneous and mucocutaneous lesions.
primary drug for all forms of the disease = Sodium stibogluconate • Cutaneous lesions can also be treated by fluconazole and metronidazole . • Mucocutaneous disease = amphotericin B
Types of leishmaniasis a) Cutaneous b) Mucocutaneous c) Visceral
Life cycle: • The sand fly transfer the flagellated promastigote form of protozoa. This is rapidly phagocytosed by macrophages. • In the macrophage the promastigote rapidly changes to nonflagellated amastigote and multiply killing cell. • The newly released amastigote are again phagocytized and the cycle continues
Treatment • Pentavalent antimonials, such as sodium stibogluconate • And with pentamidine and amphotericine as a backup therapy.
SODIUM STIBOGLUCONATE Pentavalentantimonials include: • Sodium stibogluconate. • Meglumineantimonate. • Generally considered as first line agents for cutaneous and visceral leishmaniasis
Mechanism of action: • It is unknown • Evidence for inhibition of glycolysis in the parasite at the phosphofructokinase reaction has been found.
Pharmacokinetics: • It does not get absorbed orally • It is administered parenterally in a dose of 20mg/kg /day IM or slow IV infusion for 20 days for cutaneous leishmaniasis and 28 days for visceral and mucocutaneous disease. • It can be diluted in 5% dextrose for ease of administration.
It is distributed in extra vascular compartment • It is excreted in urine rapidly, 70 % being excreted within 6 hours. • Half life ranges between 2 to 24 hours. • More than one course may be required.
ADVERSE EFFECTS: • Pain at the injection site • Gastrointestinal upset • Cardiac arrhythmias, Brdycardia, hypotension Cardiac monitoring should be performed, if central chest pain occurs, the drug must be stopped. • Myalgia, Arthralgia • Fever, Cough, &Headache • Serum amylase may increase to 4 times the normal if the level is raised greater than 4 times the drug must be stopped. • Renal and hepatic function should be monitored regularly • Hemolytic anemia • Resistance is frequent
PENTAMIDINE ISETHIONATE • It is used as an alternative to sodium stibogluconate for the treatment of visceral leishmaniasis and sometimes used for cutaneous lesion, but not routinely. • It is given in a dose of 2-4 mg/kg IM daily or every other day up to 15 days
Pharmacokinetics: • It is not absorbed orally • It is accumulated and eliminated very slowly in urine • It has a half-life of 12 days • Its mechanism of action is unknown
Adverse effects • Pain at the site of injections • Hypotension • Tachycardia • Dizziness • Dyspnea • Pancreatic toxicity hypoglycemia* * pacreatic enzyme polysaccharide degradation surge absorption
Reversible renal insufficiency • GIT disturbances • Cardiac arrhythmia • Abnormal liver function tests • Rash, metallic taste, fever. • Hypocalcemia, thrombocytopenia, hallucination. • It can also be used for the treatment of pneumocystis pneumonia and African trypanosomiasis
MILTEFOSINE • It is an alkylphosphocholine analog • It is used in the treatment of visceral leishmaniasis • It is first orally effective drug, and is administered 2.5 mg/kg daily for adults
Adverse effects • Gastrointestinal disturbances • Elevation in liver transaminase and nephrotoxicity • Teratogenic (avoid in pregnancy)
Amphotericin B An antifungal drug which can be used as an alternative therapy for visceral leishmaniasis resistant to sodium stibogluconate. • The liposomal form has shown excellent efficacy. 3mg/kg/day on day1-5, 14 and 21. • Non-liposomal 1mg/kg/day IV on every other day for 30 days.