malaria parasite
TRANSCRIPT
Malarial parasite
Presented by :MARIAM RAZIB.S Medical Technology 5th semester
MALARIAItalian, Mala “bad” aria “air”
• Malaria is a mosquito borne parasitic disease• Caused by plasmodium parasites• Transmitted by the sting of the Anopheles mosquito
or by a contaminated needle or transfusion• Tropical and subtropical regions• 300 to 500 million cases annually• Mortality rate is 1.1-2.7 million / year• One death every 20 to 30 seconds, somewhere in
the world
HISTORY OF MALARIA
• The first evidence of malaria parasites had been found in mosquitoes preserved in amber from the Paleogene period that are approximately 30 million years old
• 500 B.C_ Hippocrates Classified the fever types Noted relation ship b/w
enlarged spleen and marshes
• First Century AD_ Roman writersAttributed malarial
diseases to the swamps
• 1880-laveran_ discovered plasmodium in human blood
• 1885- Golgi_ erythrocytic schizogony in man
• 1894 – Manson_ role of mosquito in malaria
• 1857-Ronald Ross _ sexual cycle in mosquito
• 1948-Short and Graham _ pre erythrocytic schizogony
• 1969 – Rudzinska – fine structure of plasmodium
Malarial parasite
• There are four species of Plasmodium that cause Malaria in man :
P. falciparum (malignant, TERTIAN)P. vivax (benign, TERTIAN) P. ovale (TERTIAN)P. malariae (QUARTAN)
Life cycle of malarial parasite
Lab Diagnosis
Method used to diagnose:
• Microscopy• Serology – Rapid Diagnostic Tests• Molecular biology method (PCR)
Microscopy
• Gold standard • Highly sensitive, specific • Laboratory diagnosis of malaria can by made
through microscopic examination of thick or thin blood smear
Thick smears are used for screening purposes
Thin smears are for morphological detail and species identification
Appearance of thick and thin smear
Staining methods
• Giemsa staining • Lieshman's stain
• Field’s stain
Microscopic Findings
• The four Plasmodium species that cause human malaria can be distinguished most of the time (but not always) based on the morphology of their blood stages
The distinguishable stages:
• Ring form trophozoite
• Trophozoite
• Shizont
• Gametocyte
DIAGNOSTIC POINTS
P. falciparum P. vivax
RBC Size Not enlarged Enlarged
RBC Shape
Round, sometimes crenated Amoeboid
Stippling Rarely, Maurer’s clefts can be seen. Schuffner's dots
Pigment Black or dark brown Golden brown granules
Ring Fine ring, multiple infection1-2 small chromatin dots
Thick ring , often irregularone chromatin dot
Trophozoite Ring enlarged slightly irregular Irregular, amoeboid
Schizont Medium size; rarely seen in peripheral blood 19-32 merozoite
Large; 12-18 merozoite; arranged irregularly
Gametocyte
Crescent shape Spherical; compact
Trophozoite
Shizont Gametocyte
Maurer's clefts. Ring
P. falciparum
Trophozoite
Gametocyte
Shizont
Rings
P. vivax
DIAGNOSTIC POINTS
P.MALRIAE P.OVALE
RBC Size Not enlarged Enlarged
RBC Shape Elongation Fimbriation
Stippling Ziemann's dots, Schuffner's dots
Pigment Dark black. Black to brownish-black.
Ring Thick ring; one chromatin dot Rings large and coarse, one chromatin dot.
Trophozoite Band forms are a characteristic of this species.
Round , compact
Schizont Small; 9-10 merozoite arranged as rosette
Medium size; 8-14 merozoite arranged irregularly
Gametocyte Similar to P. vivax, but smaller Like P. vivax, but smaller
Rings Trophozoite
Shizont Gametocyte
P.MALRIAE
Rings Trophozoite
Shizont Gametocyte
P.OVALE
Reporting of blood film
• 1-10 per 100 high power fields….........................+
• 11-100 per 100 high power fields…………………+ +
• 1-10 in every high power fields……………………. + + +
• More than 10 in every high power fields………….. + + + +
Other findings :
• Normocytic and normchromic
• Hemoglobin: Anemia is common in malaria.
• Reticulocytes count: Reticulocytosis
• Total leukocyte count: Leukopenia is seen
• Platelet count: Thrombocytopenia
• Prothrombin time : Rises
81.4%
17.9%
1%0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
P.vivax P.falciparum P.vivax &
falciparum
P.vivax
P.falciparum
P.vivax &
falciparum
MALARIAL PARASITE REPORTED IN LNH 2008
COMPLICATIONS
• Cerebral malaria • Adult respiratory distress syndrome (ARDS)• Black water fever (severe hemolysis)• Renal failure• Tropical splenomegaly syndrome (TSS)• Bone Marrow Depression • Hypoglycemia • Anemia
Malaria control
Spry insecticides :(e.g. DDT)
Use mosquito nets, screen, or mosquito repellents to protect the person from mosquito bites.
Reconstruction of environment: eradicate the breeding places of mosquitoes.