Loaose

Loaosis (also lolase, loalose) is a disease caused by the parasite Loa loa (Czech hairy eye). It is a species of nematode that belongs to the branches. It occurs mainly in tropical West and Central Africa, where 20-30 million people are infected. The vector of the parasite is the bug, which also serves as an intermediate host. The reservoir is man.

Life cycle
The person is attacked by a bug that is infected. During blood sucking, the hairy larvae reach the subcutaneous tissue, where they mature in adulthood and copulate. Subsequently, the female produces live larvae (microfilariae), which float in the blood during the day (so-called microfilaria diurna) and wait for another bug to suck. Adults remain unwrapped under the skin, where they can live for up to 17 years.

Clinical signs
People from the endemic area are usually asymptomatic. On the contrary, infected travelers first show fever, rash and migrating subcutaneous edema, the so-called calabar swellings. The swellings are often located on the limbs and around the joints. The hump moves variously in the subcutaneous tissue at a rate of approximately 1 cm / min. Local swelling is elastic to the touch and can reach the size of a chicken egg (so-called Kalabar bumps or Cameroon bumps).

If adults migrate into the eye, the conjunctiva becomes red, severe conjunctivitis, lacrimal vesicles, visual disturbances, eyelid edema (so-called eye louse) develop.

Diagnosis

 * Microscopy: detection of microfilariae in peripheral blood (taken every 6 hours during one day).
 * Detection of specific serum antibodies.
 * Detection of specific circulating antigens.

Therapy

 * in 1–10% of patients it can cause severe allergic reactions (pruritus, rash and swelling of the skin - so-called Mazzotti reactions), therefore corticoids are added to the treatment.
 * Surgical removal of the parasite.

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