Blood and Tissue Flagellates

• Have locally acquired infections due to blood and tissue flagellates been documented in the Philippines?

  No, they have not yet been documented.
• What are the main groups of hemoflagellates in the Phylum Sarcomastigophora?

  • Leishmania spp.
  • Leishmania tropica
  • Leishmania braziliensis
  • Leishmania donovani
  • Trypanosoma spp.
  • Trypanosoma gambiense
  • Trypanosoma rhodesiense
  • Trypanosoma cruzi
• Where do hemoflagellates live?

  They live in the blood and tissues of man and other vertebrate hosts and in the gut of the insect vectors.
• What are the key morphological features of hemoflagellates?

  They have a single nucleus, a kinetoplast, and a single flagellum.
• What shape is the nucleus of hemoflagellates?

  The nucleus is round or oval.
• What does the kinetoplast of hemoflagellates consist of?

  The kinetoplast consists of a deeply staining parabasal body and an adjacent dotlike blepharoplast.
• What is the structure of the flagellum in hemoflagellates?

  The flagellum is a thin, hairlike structure that originates from the blepharoplast.
• What are the four morphologic forms of Trypanosoma spp.?

  
  

  Amastigote

  • Round, ovoid, usually found in small groups in tissues, does not contain flagellum
  • 
    
  • 
    
  • Promastigote
  • Lanceolate, elongated with a flagellum

  1. Epimastigote

  • Elongated, has undulating membrane

  1. Trypomastigote

  • Elongated, spindle shape, long slender or short stumpy, C, U, S-shaped
• What is the primary organ affected in chronic trypanosomiasis caused by T. cruzi?

  The primary organ affected is the heart.
• What is "Chagoma" in relation to Chaga's disease?

  Chagoma is a furuncle-like lesion, inflammation at the site of inoculation.
• What are the symptoms of acute trypanosomiasis?

  Symptoms include generalized lymphadenopathy and focal or diffuse inflammation mainly affecting the myocardium.
• What is "Romaña's sign" associated with Chaga's disease?

  Romaña's sign is edema of the eyelid if the parasite penetrates through the conjunctiva.
• What are the characteristics of chronic trypanosomiasis?

  Chronic trypanosomiasis may last for 20 years or more without characteristic symptoms.
• What is the infective stage of T. cruzi to the vector?

  The infective stage to the vector is the trypomastigote.
• What specimens are used for diagnosing Chaga's disease?

  Specimens include blood, CSF, fixed lymph node tissues, and lymph juices.
• What laboratory tests are used for diagnosing Chaga's disease?

  • Complete patient history
  • Stained smear (Giemsa staining)
  • Concentration methods (Microhematocrit)
  • Blood cultures (NNN medium)
  • Xenodiagnosis
  • Serologic tests (IFAT, CFT, IHAT, ELISA)
  • Molecular testing (PCR)
• What are the primary treatments for Chaga's disease?

  Nifurtimox and Benznidazole.
• What are the prevention and control measures for Chaga's disease?

  • Vector control (insecticide spraying)
  • Screening and sterilization of transfusion blood
  • Health education
• What are the characteristics of the Trypanosoma brucei complex?

  • Belongs to the trypanosome family Salivaria
  • Found in the saliva of the vector
  • Includes:
  • Trypanosoma brucei gambiense
  • Trypanosoma brucei rhodesiense
  • Trypanosoma brucei brucei
• What is the earliest sign of African trypanosomiasis?

  The earliest sign is a chancre, which is a hard, painful lesion at the site of inoculation.
• What are the two stages of human African Trypanosomiasis?

  1. Early/Acute phase

  • Hemolymphatic phase with parasite proliferation in lymphatic and blood stream

  1. Late phase/Chronic phase

  • Meningoencephalitic stage with CNS involvement
• What is antigenic variation in Trypanosomes?

  Antigenic variation is the ability of Trypanosomes to continuously change their surface coat to evade the host's immune system.
• What are the symptoms of Gambian trypanosomiasis?

  Symptoms include fever, headache, joint and muscle pain, tachycardia, dizziness, and rashes.
• What is "Winterbottom's sign"?

  Winterbottom's sign is the enlargement of the posterior cervical lymph node with a ripe plum consistency.
• What are the symptoms of chronic Gambian trypanosomiasis?

  Symptoms include severe headache, alternately morose and excitable behavior, and lack of interest in work.
• How does Rhodesian trypanosomiasis differ from Gambian trypanosomiasis?

  Rhodesian trypanosomiasis is more rapid and fatal, with CNS involvement appearing early.
• What specimens are used for diagnosing African trypanosomiasis?

  • Blood
  • CSF
  • Lymph juices
• What laboratory tests are used for diagnosing African trypanosomiasis?

  • Wet smear for live parasites
  • Stained smear (Giemsa staining)
  • CSF examination (mandatory)
  • Serologic tests (IFAT, ELISA, mini-anion centrifugation technique, IHAT)
• What are the treatments for African trypanosomiasis?

  Suramin sodium and Pentamidine for earlier stages; Melarsoprol for CNS involvement.
• What are the prevention and control measures for African trypanosomiasis?

  • Control of tsetse flies (traps, screens, insecticides)
  • Reduction of human infection pool
  • Trimming of bushes
• What are the etiologic agents and diseases caused by Leishmania spp.?

  • Leishmania tropica: Cutaneous leishmaniasis
  • Leishmania braziliensis: American or Mucocutaneous leishmaniasis
  • Leishmania donovani: Visceral leishmaniasis/Kala-azar/Dumdum fever
• What are the life cycles of Leishmania spp.?

  • Infective stage to man: promastigote
  • Infective stage to vector: amastigote
• What are the symptoms of cutaneous leishmaniasis caused by Leishmania tropica?

  Symptoms include skin ulcers, painless lesions, and oriental button at the inoculation site.
• What is the characteristic of American or Mucocutaneous leishmaniasis?

  It involves metastatic spread of lesions to oronasal and pharyngeal mucosa, causing disfiguring tissue destruction.
• What are the symptoms of visceral leishmaniasis caused by Leishmania donovani?

  Symptoms include twice-daily fever elevation, splenomegaly, and cachexia.
• What are the diagnostic tests for leishmaniasis?

  • Microscopic determination from tissue scrapings, lesions, and biopsy
  • Culture (unreliable)
  • Serologic tests (Complement Fixation Test, Montenegro's intradermal test, IFAT)
• What is the primary treatment for leishmaniasis?

  Pentavalent antimonials: sodium stibogluconate and nmethylglucamine antimonite.
• What are the second-line drugs for leishmaniasis treatment?

  • Amphotericin B
  • AmBisome
  • Pentamidine
  • Miltefosine
  • Topical paromomycin
  • Combination therapy
• What are the prevention and control measures for leishmaniasis?

  • Protect skin lesions from insect bites
  • Health education