Guinea Worm Disease (Dracunculiasis)

Introduction

Dracunculiasis otherwise called Guinea worm disease is an infection by a very long nematode, Dracunculus medinensis.

It is contracted through drinking water
contaminated with water fleas (cyclops) infected with Dracunculus.

Except for remote villages in Rajastan desert of India and Yemen the disease is now only seen in Africa, between the Sahara and Equator.

Pathophysiology

In the stomach, the larvae penetrate into the mesentery, where they mature sexually in 10 weeks.

The female worm burrows to the cutaneous surface to deposit her larvae, causing specific skin manifestations.

When the parasite comes in contact with water, the worm rapidly discharges its larvae, which are ingested by the cyclops.

Symptoms and Clinical features of dracunculiasis

As the worm approaches the surface it may be felt as a cord-like thickening.
It forms an indurated cutaneous papule
Several hours before the head appears at the skin surface there is (at the point of emergence)
Local erythema
Burning sensation
Pruritus:
Tenderness
Soon after, the papule blisters and a painful ulcer develops, usually on the leg
Ulcer may occur on other parts of the body e.g. the genitalia, buttocks, or arms

Differential diagnoses

Sickle cell ulcer
Stasis ulcer

Complications of dracunculiasis

Secondary infection
Cellulitis
Erysipelas
Progressive lymphoedema
Oesteomyelitis
Arthritis
Tetanus

Investigations

Radiograph of the affected area:

If osteomyelitis and arthritis (or calcified worms) are suspected

Treatment for Dracunculiasis

Treatment objectives

Resolve local inflammation to permit easier removal of the worm
Extract the worm
Prevent and treat complications

Drug treatment

Metronidazole

Adult: 500 mg orally every 8 hours for 7 days

Child: 7.5mg/kg orally every 8 hours

Or:

Mebendazole

Adult: 400-800 mg orally daily for 6 days

Child over 1 year: usually 100 mg orally twice daily for 3 days

Or:

Ivermectin

Adult: 200 micrograms/kg orally as a single dose

Child: Consult specialist

Treat or prevent complications with antibiotics

Worm extraction

Traditionally:

Extract the worm slowly by winding it about a match stick or twig, removing 3-5 cm daily, with care not to rupture it.

In the event of such an accident, the larvae escape into the tissues and produce fulminating inflammation.

The process appears to be facilitated by
placing the affected part in water several
times a day

Notable adverse drug reactions, caution and contraindications