IaD [018-019] Leishmania Infection PDF 2024-2025
Document Details
New Giza University
2024
NGU
Azza El-Adawy
Tags
Summary
This document provides an overview of Leishmania infection, including its transmission, types, and diagnostic methods.
Full Transcript
IaD [018-019] Leishmania species Parasite affecting human blood and tissues Leishmaniasis Prof. Dr. Azza El-Adawy Professor of Medical Parasitology 2024-2025 Key groups of parasites affecting man Leishmania belongs to which key group of parasites? I- M...
IaD [018-019] Leishmania species Parasite affecting human blood and tissues Leishmaniasis Prof. Dr. Azza El-Adawy Professor of Medical Parasitology 2024-2025 Key groups of parasites affecting man Leishmania belongs to which key group of parasites? I- Metazoan Parasites II- Protozoan Parasites termed Helminths termed Protozoa Body is composed of one cell Body is composed of Leishmania species organs and systems belong to Protozoa 11/11/2024 Infection & Defence Module 3 Key groups of Protozoa affecting man Leishmania belongs to which key group of Protozoa? Amoeba Ciliates Sporozoa Flagellate Leishmania species belong to Flagellates 11/11/2024 Infection & Defence Module 4 Arthropods transmitting/causing diseases to man Parasite of Today’s Lecture is transmitted by the bite of which arthropod? e.g. Sand fly Mosquitoes Flies Lice Mites Ticks Fleas Bugs 11/11/2024 Infection & Defence Module 6 Characters of species of Leishmania parasite 1- It acquires two developmental stages Amastigote Promastigote Develops inside patient’s body Develops outside patient’s body 2- Differentiated by isoenzyme analysis, molecular methods, or monoclonal antibodies Phlebotomus papatasii Lutzomyia 3- All species are transmitted to man through the bite of infective female Sand fly 11/11/2024 Infection & Defence Module 7 How does sand fly transmit Leishmania infection to man? It takes Amastigotes from skin or Amastigote blood while biting the patient Amastigote stage of Leishmania develops inside sand fly into Promastigote stage It injects Promastigotes at the site Promastigote of bite to infect the healthy man 11/11/2024 Infection & Defence Module 8 When infective sand fly bites man, injected Leishmania promastigotes Liver Leishmania attacks human skin cutaneous leishmaniasis Leishmania attacks human viscera visceral leishmaniasis 11/11/2024 Infection & Defence Module 9 Areas where Leishmania infections exist enetmd.com 11/11/2024 Infection & Defence Module 10 Cutaneous Leishmaniasis First, click here to watch this video First, click here to watch this video 11/11/2024 Infection & Defence Module 11 Pathogenesis of Cutaneous leishmaniasis Promastigotes are engulfed by skin macrophage where they turn into amastigotes lymphocytes and plasma cells infiltrate the area blogs.biomedcentral.com Promastigotes are injected in Multiplying amastigotes patient’s skin at the site of bite Nodule forms at the site of bite due to 1- multiplication of Leishmania in skin macrophages 2- and granulomatous reaction around them 11/11/2024 Infection & Defence Module 13 Clinical Picture of Cutaneous leishmaniasis Nodule An ulcer forms with sharp-cut indurated margin In about one year Healing occurs leaving A disfiguring scar noonepress.com The patient develops permanent immunity to the infecting Leishmania species 11/11/2024 Infection & Defence Module 14 Leishmania species in the Middle East & Africa causing skin ulcer 1- Leishmania tropica 2- Leishmania major 3- Leishmania aethiopica Causes dry ulcer Causes wet ulcer Causes nodular lesions that do not heal or ulcerate Called Oriental Sore Occur in infected immunodeficient patients 11/11/2024 Infection & Defence Module 15 Leishmania species in South America causing skin ulcers Leishmania species Leishmania species Cause dry ulcer Causes muco-cutaneous leishmaniasis Leishmania species escolarship.org Cause diffuse lesion resembles spread along lymphatics to mucous lepromatous leprosy (does not heal membrane producing erosion of nasal 11/11/2024 or ulcerate) Infection & Defence Module septum, palate & larynx 16 Leishmania species in Central America causing skin ulcers Leishmania species Single ulcer affects the ear causing destruction of the cartilage (Chiclero’s ulcer or Bay sore) Leishmania species 11/11/2024 Infection & Defence Module 17 Clinical Diagnosis of Cutaneous Leishmaniasis The patient presents with an ulcer with sharp cut indurated hard and rough margin flicker.com enetmd.com dermatologyoasis.net 11/11/2024 Infection & Defence Module 18 Laboratory Diagnosis of Cutaneous Leishmaniasis 1- Detect amastigote stages microscopically at the edge of the ulcer Amastigotes Necrotic tissue tulane.edu The sample is obtained by aspiration, scrapping or biopsy Aspiration cdc.gov Leishmania amastigotes (Giemsa stained 100X) tulane.edu 11/11/2024 Infection & Defence Module Scrape or take biopsy 19 Diagnosis of Cutaneous Leishmaniasis (continued) 2- Culture of aspirate or scraping from edge of the ulcer on suitable medium to detect promastigotes After isolation, parasites can be characterized to the species level using isoenzyme analysis cdc.gov Promastigote stage of Leishmania This diagnostic method takes several weeks before results are obtained 11/11/2024 Infection & Defence Module 20 Quiz A 30-year-old man has a wound on the back of his neck after an insect bite. The wound is big with raised sharp edge & indurated margin. He works as a tourist guide in North Sinai. The condition is diagnosed as parasitic infection after culturing an aspirate from the edge of the ulcer. What is recovered in the culture? a) Amastigote forms b) Promastigote forms c) Gametocyte stages d) Trypomastigote forms e) Sporozoite stages 11/11/2024 Infection & Defence Module 21 Visceral Leishmaniasis Next slide shows areas of infection worldwide Then watch a video in the following slide that shows visceral leishmaniasis cases in India Liver where first human infections where recorded 11/11/2024 Infection & Defence Module 22 World Distribution of Visceral Leishmaniasis Leishmania infantum Leishmania Leishmania chagasi donovani Female sand fly exists 11/11/2024 Infection & Defence Module 23 Visceral Leishmaniasis in India https://www.youtube.com/watch?v=yr-01IPiz0g (also called Kala azar means black fever) 11/11/2024 Infection & Defence Module 24 Pathway of visceral Leishmania species inside patient’s body A swelling that is rarely seen at the site of bite Skin macrophage amastigotes move via blood stream Taken by cells of the Amastigotes Promastigotes reticuloendothelial system in multiplying amastigotes patient’s viscera Re-visit Histology: Cells of RES include macrophages, monocytes & leucocytes 11/11/2024 Infection & Defence Module 25 Pathogenesis of Visceral Leishmaniasis Reticulo-endothelial cells are found in: Red cell count RBCs Liver & spleen Hepatosplenomegaly Bone marrow Aplastic anemia Leishmania Leukocyte Bone WBCs amastigotes count marrow High level of immunoglobulins in blood Lymph nodes Enlarged lymph nodes Platelets Platelet count Intestinal mucosa Diarrhoea & dysentery Called pancytopenia 11/11/2024 Infection & Defence Module 26 Clinical Picture of Visceral Leishmaniasis 1- Fever: intermittent with double daily rise (called spiking fever) Also called Dum-dum fever Dum-dum is a town in Calcutta (India) 2- Epistaxis and bleeding from the gums 3- Massive splenomegaly www3.paho.org 4- Hepatomegaly & lymphadenopathy Case with massive splenomegaly 11/11/2024 Infection & Defence Module 27 Clinical Picture of Visceral Leishmaniasis (continued) 5- Weight loss, emaciation, death from inter-current infection as: pulmonary infections gastrointestinal infections Because Leishmania causes suppression of cell-mediated immunity of patient 11/11/2024 Infection & Defence Module 28 Clinical Picture of Visceral Leishmaniasis (continued) 6- Post kala azar dermal leishmaniasis (PKDL) ijdvl.com e-ijd.org Hyperpigmented skin areas Skin nodules Skin lesions: - Occur after incomplete treatment - Seen in patients from the old world (India & East Asia) High concentrations of interleukin 10 in the peripheral blood of visceral leishmaniasis patients predict the development of PKDL 11/11/2024 Infection & Defence Module 29 Why PKDL develops? (Immunological Explanation) - During disease, mononuclear cells in blood do not produce interferon gamma - After treatment, mononuclear cells start to produce interferon gamma - Interferon gamma cause skin inflammation as a reaction to persisting parasites in the skin. - At this stage the patient is infective to biting sand fly. 11/11/2024 Infection & Defence Module 30 Used Regimen for Diagnosis of Visceral Leishmaniasis If the clinician suspects visceral leishmania infection, he passes into two steps: Step 1: Request for Complete blood Count (CBC) If red blood cell, white blood cell and platelet counts are reduced. Move to Step 2: labcompare.com 1- Perform Bone marrow aspirate/biopsy (or liver, lymph node, spleen biopsy) It is a confirmatory test to view Leishmania amastigotes 11/11/2024 Infection & Defence Module 31 The procedure of Bone marrow aspirate from sternum https://www.youtube.com/watch?v=OKP4SLwh3do&has_verified=1 11/11/2024 Infection & Defence Module 32 Laboratory Diagnosis of Visceral Leishmaniasis (continued) 2- Culture: of patient’s blood or material from liver, spleen, lymph node or bone marrow on suitable medium to detect promastigotes Advantages of this diagnostic method Parasites can be characterized to the species level using isoenzyme analysis Disadvantages of this diagnostic method It takes several weeks till results appear 11/11/2024 Infection & Defence Module 33 Laboratory Diagnosis of Visceral Leishmaniasis (continued) 3- Using Buffy Coat Method to detect Leishmania amastigotes Plasma Buffy coat RBCs labcompare.com In positive cases: WBCs, platelets, parasite are viewed microscopically in this buffy coat Put in the centrifuge Patient’s blood After centrifugation 11/11/2024 Infection & Defence Module 34 Laboratory Diagnosis of Visceral Leishmaniasis (continued) 4- Serological tests To detect anti-Leishmania antibodies cbc.ca 11/11/2024 Infection & Defence Module 35 Laboratory Diagnosis of Visceral Leishmaniasis (continued) 5- Molecular techniques Commonly used as a research tool. Detection of DNA of the parasite in patient’s blood or tissues by PCR technique Advantages of this diagnostic method Rapid “results appear within days” Sensitive Identifies causative Leishmania species Disadvantages of this diagnostic method saridarlab.com Expensive diagnostic method Need a highly equipped lab Patient’s sample 11/11/2024 Infection & Defence Module 36 Treatment of Cutaneous Leishmaniasis Treatment of Visceral Leishmaniasis In Both: give sodium stibogluconate (Pentostam) given intramuscularly Recently: give Liposomal Amphotericin B (AmBisome) + Treatment of ulcer By any of the following methods - Intralesional injection of Pentostam - A paste containing paromomycin - Heating or freezing with liquid nitrogen - Plastic surgery for healed ulcers 11/11/2024 Infection & Defence Module 37 Prevention & Control of Leishmaniasis Ministry of Health’s Task Individuals’ Task ❑ Treatment of Patients ❑ Control of sand fly vector ❑ Vaccination in endemic areas gives long lasting immunity Protection: by using Wire screens, repellents & bed nets 11/11/2024 Infection & Defence Module 38 Quiz A traveler has fever that rises then falls during the day. He also has spontaneous bleeding from nose & gums. He returns from a two-month visit to India. He recalls having a painful insect bite. The condition is diagnosed as parasitic infection after examination of bone marrow aspirate. What is the site of parasite location in patient’s body? a) Red blood cells b) Reticuloendothelial cells c) Over bony prominences d) Skin at interdigital spaces e) Liver parenchyma cells 11/11/2024 Infection & Defence Module 39 Suggested Textbooks & Websites Paniker’s Textbook of Medical Parasitology https://www.cdc.gov/dpdx/az.html Best Wishes 11/11/2024 Infection & Defence Module 40