Tissue nematodes are group of parasites that cause serious devastating form of diseases when neglected

1. LYMPHATIC FILARIASIS
Huda Alislam Talab
B.Sc., M.Sc. Medical Parasitology
University of Medical Sciences and Technology (UMST)

2. ADULT WORM
• Adult worms are located in the
lymphatic vessels and lymph
nodes
• They are long, slender, creamy
white thread like

4. MICROFILARIAE
• Microfilariae are the
diagnostic forms, found
in the blood vessels
• Covered by a long
hyaline sheath

5. Microflaria of Wuchereria bancrofti

8. MICROFLARIA OF BRUGIA

9. CHYLURIA

10. Sample
Microfilariae can be found in blood, and hydrocele fluid,
urine or other body fluids
Methods
• Direct wet amount
• Thick smear stain
• Concentration technique
• DEC provocation test

11. Direct wet mount
Movement of microfilariae
Thick smear
Stained to observe the sheath and nuclei of
microfilaria

12. CONCENTRATION TECHNIQUES
Blood can be examined after concentration
techniques to increase sensitivity
- Membrane filtration technique
- Centrifugation technique

13. DEC PROVOCATION TEST
• This test is done to collect the blood in the day
time
• Patient takes a tablet of DEC orally (2mg/kg) so
that the nocturnal microfilariae are stimulated
and come to peripheral blood within 30 minutes

14. COLLECTION TIME
• Should be based on the periodicity of the
microfilariae.
• Nocturnal periodicity, blood should be collected
between 9 pm and 2 am.
• Diurnal periodicity between 10am - 3pm.

15. XENODIAGNOSIS
• Mosquitoes are allowed to feed on the infected patients
and are dissected 4–6 weeks later to demonstrate
microfilariae.

16. X-Rays
• Dead and calcified worms
• Pulmonary infiltrates in patients with TPE.
Ultrasound
• Anatomical abnormalities of lymphatics vessels
• Filarial dance sign: movement of adult worms
within the lymphatic vessels of scrotum

19. HYDROCELE OF SCROTUM

27. LOA LOA

28. • Detecting microfilariae of Loa loa in the peripheral
blood during the day (diurnal ) (10.00–15.00 h
Peak 13.00 h).
• Isolation of the adult worm from the eye or biopsy
of subcutaneous swelling
• Occasionally L.loa microfilaria can be found in
joint fluid

29. LOA LOA MICROFILARIA
Sheath is present
Nuclei extend to the end of the tail

32. DEER FLY (CHRYSOPS)

33. HORSE FLY

38. CALABAR SWELLING

42. ISOLATION ADULT OF LOA LOA
FROM EYE

43. ONCHOCERCA VOLVULUS

44. • Detection of microfilariae in a skin snip smear is
the gold standard method for diagnosis of
onchocerciasis.
• They may also be found in the conjunctiva and
rarely in peripheral blood.

45. O.VOLVULUS MICROFILARIA
• Unsheathed and non-periodic
• Head is slightly enlarged.
• No nuclei in the end of the tail
which is long and pointed.

46. SKIN SNIPS TECHNIQUE
Common sites
• Iliac crests, shoulders and lower limb.

47. SKIN SNIPS TECHNIQUE
• Skin is lifted by a needle
and a small piece with a
sterile blade
• After incubating the biopsy
tissue in saline,
microfilariae emerge from
the skin

48. DETECTION OF THE ADULT
WORM
• It can be done from the biopsy of the subcutaneous
nodules

49. SEROLOGY
• IgG4 specific dipstick assay can detect the active
infection.
• A rapid card test using antigen OV16 to detect
IgG4 in serum has been evaluated.

50. MAZZOTTI SKIN TEST
(DEC PATCH TEST)
•Topical application of DEC on the skin leads
to local reaction (erythema and itching) to the
dead worm. Sometime, the reaction is much
severe in heavy infection. Hence this is done
only in light infection without eye
involvement

51. SIMULIUM (BLACK FLIES)

52. ONCHOCERCOMAS

54. SOWDA

58. LEOPARD SKIN

59. ELEPHANT SKIN

61. OCULAR
ONCHOCERCIASIS

64. DRACUNCULUS MEDINENSIS

65. BLISTER FORMED IN
DRACUNCULIASIS

66. • Detection of adult worm: when the gravid female
worms appear in the blisters. The calcified adult
worms from the deeper tissue can be detected by X-
ray
• Detection of L1 larvae: On contact with cold water
placed on the leg ulcer, a large number of motile
larvae are discharged which can be examined under
microscope
• Antibody detection: can be detected by ELISA.

67. Adult of Guinea worm

68. DRACUNCULUS MEDINENSIS (ADULT
FEMALE WORM) EMERGING FROM THE
BLISTER

75. Larva of D.medinensis

76. Cyclops

77. WATER FILTER TO PREVENT
INFECTION BY GUINEA WORM

80. DRINKING THROUGH FILTER