Naegleria fowleri

Naegleria fowleri - M.Vignesh, Zentronz, G.T.M.College, Thiruvarur

1. - M.Vignesh Zentronz g.t.m.c Naegleria fowleri

2. It is a brain eating amoeba Causes an acute and fulminating primary amoebic meningoencephalitis Lives in water such as lakes & swimming pools

3. Morphology: Naegleria fowleri Stage 1 : Stage 2 : - Trophozoites -Cyst -Amoeboid -Flagellate

4. Trophozoite : - Length : 10-20 m - Motile by mean of rounded psirdopodia called lobopodia -Nucleus has large central karyosome -No pheripheral nuclear chromatin

5. Trophozoite : -Pear shaped -Two flagella present in anterior end -Moves rapidly forward . Or spines slowly in circle -This form does not multiply

6. Cyst: -Spherical, - Uninicleate , -Diameter : 7-10 m -Surround by thin cyst wall -Cyst and flagellate forms have never been found in tissue and CSF

7. Mode of infection : Acquire infection by swimming in fresh water lakes or swimming pools containing infective forms of N.fowleri Or acquired by inhaling dust cointaining infective forms

8. Life cycle:

9. Life cycle: Life cycle is completed in external environment Amoboid form is multiplies by binary fission Amoeboid form is invasive stage of the parasite Flagellate form of trophozoite helps in the spread of N.fowleri to new water bodies

10. Pathogenesis: Amoeboid form Enters through nasal mucosa Invades criform plate Olfactory nerve to brain Primary amoebic meningoencephalitis

11. Clinical features: Incubation period : 2- 15 days (Average 5 days) Severe fontal headache Fever (39 -40deg. C) Meningeal irritaion Visual distrabance Confusion Seizures Coma

12. Laboratory diagnosis: Specimen: -CSF is collected for demonstration of amoebae Microscopy: -Staining with Wright or Giemsa stains or Fluorescent stains -Appeared as small pink nuclei with sky blue cytoplasm

13. Contd … Culture: -Culture media: Non-nutrient agar -Inoculated overnight at 37deg.C -Grown on moist agar surface Histologic examination: - Immunoflurescence & immunoperoxidase methods

14. Treatment: Amphotericin B is used for treatment and is clinically effective