Plasmodium

• Maurer's clefts/ dots


  Comma- like red dots
• Hemozoin


  Brown pigment in blood smears
• Microgametocyte


  Sausage shaped
• Incubation period of plasmodium vivax

  12 to 20 days
• Schuffner's dot


  eosinophilic stippling called
• Ziemann's dot


  rarely detected stippling
• Plasmodium knowlesi


  Quotidian malaria
• Incubation period of plasmodium malaria

  18 to 40 days
• Plasmodium vivax


  Its ring form has signate appearance
• Renewed asexual parasitemia


  causes the relapse malaria
• Thin smear


  used for specie detection
• Schizont of plasmodium ovale

  8 merozoites
• Giemsa


  stained used for thin and thick smear
• Microgametocytes


  male gametocytes
• Protein


  present in the urine if the patient has plasmodium malaria infection
• Gametocyte


  Infective stage to mosquito
• Ookinete


  Penetrates the wall of mosquito stomach
• Sporogony


  Production of sporozoites within the oocyst
• Paroxysmal cycle of plasmodium malaria

  72 hours
• Malarial parasites


  Intracellular protozoans

  
• Malarial parasites


  • Vector-borne: Female Anopheles
  • Intermediate host: MAN
  • Habitat: Liver and RBCs of humans
  • MOT: Mosquito bite, blood transfusion, congenital

  
• Diagnosis


  Microscopy (thick and thin smear)
• The term malaria originates from Medieval Italian: mala aria "bad air". The word was coined during the medieval period when people believed that the disease was caused by the foul-smelling air coming from marshes and swamps.
• Life cycle


  1. Infective stage to man: SPOROZOITES

  2. Infective stage to mosquito: GAMETOCYTES (Microgametocytes: MALE, Macrogametocytes: FEMALE)

  
• Plasmodium falciparum


  • Most prevalent Plasmodium in the Philippines
  • Malignant Tertian Malaria
  • Paroxysmal Cycle: 36-48 hours
  • Ring forms: Delicate small ring, Marginal form, May have 2 chromatin dots, Common multiple rings in an RBC (Headphone/smiley)
  • Schizont: 8-36 merozoites (rarely seen), Schizogony happens in the blood vessels of the internal organs
  • Stippling: Maurer's Clefts/dots (Comma or wedge; Comma-like red dots)
  • Microgametocyte: Sausage shaped; Diffuse chromatin
  • Macrogametocyte: Crescent shaped; Compact chromatin
  • Type of RBC infected: All forms (high rate of infectivity)

  
• Plasmodium falciparum (complications)


  • Incubation period: 8 to 15 days; 11 days (shortest)
  • Anemia is more pronounced (targets all types of RBCs)
  • Severe blackwater fever: An increase in RBC destruction leads to the release of hemoglobin in the urinary system, which oxidizes and becomes black (Hemoglobinuria: hemoglobin in the urine)
  • Disseminated intravascular coagulation (DIC): Blood clots form throughout the body (blocking the small blood vessels)
  • Tropical Splenomegaly Syndrome: Enlargement of the spleen because of recirculation of destroyed RBCs
  • Hemozoin: brown pigment in blood smears and vessels, Metabolic product of parasite
  • CNS involvement is common (Cerebral malaria, Affects blood vessels that supply the brain)
• Plasmodium vivax


  • Most prevalent species (widest distribution)
  • Benign Tertian Malaria
  • Paroxysmal Cycle: 48 hours
  • Incubation period: 12 to 20 days
  • Type of RBC infected: Young RBCs (reticulocytes)
  • Ring Forms: Large ring form; big/heavy chromatin dot, Signet ring appearance
  • Schizont: 12-24 merozoites
  • Microgametocyte: Round, Large pink to purple chromatin mass surrounded by a pale halo
  • Macrogametocyte: Round, Eccentric chromatin mass
  • Stippling: Schuffner's dots, Eosinophilic

  
• Plasmodium ovale


  • Ovale Tertian Malaria
  • Type of RBC infected: Young RBCs (reticulocytes)
  • Incubation period: 11 to 16 days
  • Paroxysmal Cycle: 48 hours
  • Parasitized RBC: May come with a serrated or fimbriated edge, Comet form
  • Stippling: James' dots
  • Schizont: 8 merozoites

  
• Plasmodium vivax and Plasmodium ovale


  • Cause relapses "Renewed asexual parasitemia"
  • Dormant liver stage (hypnozoites)
  • Factors that promote reactivation: Stress, High fever, Pregnancy, Depression, Immunocompromised patients
  • Both are benign, mild anemia
• Plasmodium malariae


  • Quartan Malaria
  • Type of RBC infected: Old RBCS (Senescent RBCS)
  • Ring Forms: Heavy chromatin dot (bird's eye appearance)
  • Developing Trophozoite: Band formation
  • Schizont: 6-12 merozoites (Rosette/fruit-pie appearance)
  • Stiplling: Ziemann's dots, Few tiny dots, rarely detected
  • Incubation period: 18 to 40 days
  • Nephrotic syndrome is common (Proteinuria)

  
• Plasmodium knowlesi

  • Parasite of long-tailed macaques (Macaca fascicularis)
  • Simian Malaria
  • Quotidian Malaria
  • Paroxysmal Cycle: 24 hours

  
• Thick and thin smear


  • Thick smear: quantification and screening of parasite
  • Thin smear: species identification
  • Stain with Giemsa

  
• Reporting

  Parasites/100-field thick field: Negative (None found in 100 fields), + (1-10), ++ (11-100), +++ (1-10/thick field), ++++ (>10/thick field)