Presentation
Such patients present with a grossly visible intraocular filarial worm on physical exam, usually with pain and photophobia. Associated vision loss at presentation has ranged from 6/24 to light perception. [eyewiki.aao.org]
Video Ocular Loiasis (00:24) A 21-year-old woman presented to our hospital with the sensation of something moving in her eye. She reported having no systemic or visual symptoms. [nejm.org]
He personally asked one of us (CABO) to report the present case in the medical literature. [scielo.br]
Table 2 Entomologic indices in the present investigation (2012) Full size table Comparison of the entomologic indicators recorded in 1999–2000 and in 2012 Results of comparisons are presented in Table 3. [parasitesandvectors.biomedcentral.com]
Entire Body System
- Swelling
Most infected people are asymptomatic, but some have areas of angioedema (Calabar swellings), which occur mainly on the extremities. [merckmanuals.com]
Calabar swellings are caused by hypersensitivity reactions and present as non-erythematous, localized edema of the subcutaneous tissue.[5] These swellings are frequently found on the limbs, where they commonly inhibit movement of the nearest joint, but [eyewiki.aao.org]
Loa loa Other names loiasis, loaiasis, Calabar swellings, fugitive swelling, tropical swelling,[1]: 439 African eyeworm Loa loa microfilaria in thin blood smear (Giemsa stain) Specialty Infectious diseases, tropical medicine Loa loa filariasis is a skin [en.wikipedia.org]
Although localized inflammation (Calabar swellings) may occur, major tissue damage is rare. Anish N. Shah, M.B., B.S. Manuel Saldana, M.D. St. Thomas' Hospital, London, United Kingdom Citing Articles (8) [nejm.org]
- Pain
Generalized itching, hives, muscle pains, arthralgias, fatigue, and adult worms visibly migrating under the surface of the skin may be observed. [rarediseases.oscar.ncsu.edu]
The swellings were very painful (46%), mildly painful (28%) or painless (26%). Most respondents (94%) reported that the swellings itched. The prevalence of L. loa microfilaraemia in most of the study villages was >20%. [ncbi.nlm.nih.gov]
When chronic, they can form cyst-like enlargements of the connective tissue around the sheaths of muscle tendons, becoming very painful when moved. [en.wikipedia.org]
The swellings develop rapidly over a few hours and may be preceded by localized pain, pruritus, and urticaria; the swellings usually last 1 to 3 days. [med-chem.com]
Less common are symptoms of itching over the entire body, muscular and joint pain as well as fatigue. [cntd.lstmed.ac.uk]
- Asymptomatic
Loiasis may either be asymptomatic or manifest as a large, transient area of localized, non-erythematous subcutaneous edema (Calabar swellings), adult worm migration through the sub-conjunctiva (''African eye worm'') and pruritus. [rarediseases.oscar.ncsu.edu]
Symptoms and Signs Most infected people are asymptomatic, but eosinophilia is common. [merckmanuals.com]
Loiasis is often asymptomatic. Episodic angioedema (Calabar swellings) and subconjunctival migration of an adult worm can occur. [cdc.gov]
Abstract Asymptomatic infection with Loa loa, an eye worm, is reported in a 32-year old Zambian woman. The patient revealed up to 28% eosinophilia but microfileraemia was not noticed. [ncbi.nlm.nih.gov]
- Inflammation
Although localized inflammation (Calabar swellings) may occur, major tissue damage is rare. Anish N. Shah, M.B., B.S. Manuel Saldana, M.D. St. Thomas' Hospital, London, United Kingdom Citing Articles (8) [nejm.org]
Laboratory abnormalities are non-specific and include eosinophilia and elevated IgE.[4]Though most infections are asymptomatic, in some patients adult worms can be directly observed migrating through the subconjunctiva, where they can cause inflammation [eyewiki.aao.org]
It is characterized by transient areas of allergic inflammation in the tissues beneath the skin, called calabar swellings; adult worms… Read More [britannica.com]
Get Update Overview Loiasis is a parasitic worm, also called Loa Loa, which causes inflammation and swelling in different parts of the body. The worm is transmitted into the body through a horsefly, deer fly or the Mango fly. [diseaseinfosearch.org]
- Fatigue
Generalized itching, hives, muscle pains, arthralgias, fatigue, and adult worms visibly migrating under the surface of the skin may be observed. [rarediseases.oscar.ncsu.edu]
Less common are symptoms of itching over the entire body, muscular and joint pain as well as fatigue. [cntd.lstmed.ac.uk]
Respiratoric
- Sputum
Microfilariae have been recovered from spinal fluids, urine, and sputum. During the day they are found in peripheral blood, but during the noncirculation phase, they are found in the lungs. The fly ingests microfilariae during a blood meal. [cdc.gov]
They can be found in the blood, lungs, urine, spinal fluid, or sputum. [web.stanford.edu]
Musculoskeletal
- Arthralgia
Generalized itching, hives, muscle pains, arthralgias, fatigue, and adult worms visibly migrating under the surface of the skin may be observed. [rarediseases.oscar.ncsu.edu]
[…] and microfilariae and provides effective prophylaxis for individuals visiting endemic regions.[39] DEC is contraindicated in patients coinfected with onchocerciasis due to risk of Mazzotti reaction, which consists of fever, tachycardia, hypotension, arthralgia [eyewiki.aao.org]
Eyes
- Foreign Body Sensation
She presented to the emergency department with complaints of foreign body sensation, irritation, and described the feeling of something moving in the left eye. [eyetube.net]
While waiting for treatment with medications available only through the Special Access Programme of Health Canada, the patient presented to the emergency department with the sensation of a foreign body in her left eye (Figure 1), and was found to have [cmaj.ca]
However, discomfort and foreign body sensation are commonly reported symptoms.[2][6][12][13][14] In rare cases, L. loa has been noted to enter the anterior chamber, and live L. loa worms have been reported in the vitreous. [eyewiki.aao.org]
Skin
- Pruritus
Loiasis may either be asymptomatic or manifest as a large, transient area of localized, non-erythematous subcutaneous edema (Calabar swellings), adult worm migration through the sub-conjunctiva (''African eye worm'') and pruritus. [rarediseases.oscar.ncsu.edu]
Onset of pruritus, in the absence of other signs. Subcutaneous migration of an adult worm: pruritic, palpable red cord-like linear lesion, sinuous, advancing (1 cm/hour), disappearing rapidly with no trace a. [medicalguidelines.msf.org]
A survey from Eastern Cameroon (n = 4146) did not determine the frequency of non-specific pruritus, but showed that among individuals with Calabar swelling pruritus occurred up to 94% [ 29 ]. [ncbi.nlm.nih.gov]
- Angioedema
Most infected people are asymptomatic, but some have areas of angioedema (Calabar swellings), which occur mainly on the extremities. [merckmanuals.com]
“Filariasis Caused by Loa loa Is Also a Cause of Angioedema.” 2008. Amer J Med 34(4). 5. Gouteux, J. P. and F. Noireau. [web.stanford.edu]
Episodic angioedema (Calabar swellings) and subconjunctival migration of an adult worm can occur. [cdc.gov]
African rainforest regions of Gabon, Cameroon, Central African Republic, Democratic Republic of the Congo and Congo, with focal areas of endemicity in Nigeria, Angola and Sudan.2 Symptoms are caused by the migration of adult worms within the skin and angioedema [cmaj.ca]
- Urticaria
The swellings may last for 1-3 days, and may be accompanied by localized urticaria (skin eruptions) and pruritis (itching). [the-medical-dictionary.com]
The swellings develop rapidly over a few hours and may be preceded by localized pain, pruritus, and urticaria; the swellings usually last 1 to 3 days. [med-chem.com]
ADJUNCTIVE THERAPY Diethylcarbamazine (DEC) therapy of loiasis is often associated with a transient exacerbation of symptoms, including urticaria and Calabar swellings. [antimicrobe.org]
Codes ICD10CM: B74.3 – Loiasis SNOMEDCT: 44250009 – Loiasis Look For Subscription Required Diagnostic Pearls Subscription Required Differential Diagnosis & Pitfalls In regions where onchocerciasis and loiasis are endemic, visitors can present with urticaria [visualdx.com]
- Subcutaneous Nodule
Movable, nontender subcutaneous nodule of Onchocerca volvulus. [emedicine.com]
In one patient, nonspecific symptoms recurred 2 years later, but unlike her symptoms before albendazole therapy, they were not accompanied by the appearance of subcutaneous nodules containing adult worms. [ncbi.nlm.nih.gov]
Some nodules may contain many male and female worms. In the subcutaneous nodules, the female worms produce microfilariae, which have a lifespan that may reach two years. [patient.info]
- Erythema
Clinical Features: The Chrysops bite results in erythema, swelling, and itching, symptoms which can worsen with the presence of infective larvae. The adult worms normally migrate through the subcutaneous tissue at a rate of about 1 cm/min. [med-chem.com]
Infected individuals develop intense pruritus between 30 minutes and 24 hours after the test, which can then be accompanied by erythema, edema, and papular dermatitis. The presence of M streptocerca may cause false-positive reactions. [emedicine.com]
No erythema, edema, or overlying break in the skin was noted. The patient noted that exposure to bright light stopped the “movement sensation” within his eyelid. [hindawi.com]
Urogenital
- Hematuria
Nephropathy generally manifests as proteinuria with or without mild hematuria and is believed to be due to immune complex deposition. Encephalopathy is usually mild, with vague CNS symptoms. [merckmanuals.com]
Syndrome loin pain-hematuria syndrome loin strap Loin-cloth LOINC ▼ [encyclopedia2.thefreedictionary.com]
Other laboratory abnormalities, including hematuria and proteinuria, can occur in Loa loa infection, but generally resolve with therapy. [antimicrobe.org]
Nephropathy generally manifests as proteinuria with or without mild hematuria and is believed to be due to immune complex deposition. Encephalopathy is usually mild, with vague central nervous system (CNS) symptoms. [msdmanuals.com]
Neurologic
- Encephalopathy
Encephalopathy is usually mild, with vague CNS symptoms. [merckmanuals.com]
Severe complications such as encephalopathy have been reported in highly infected individuals receiving ivermectin during mass drug administration programs for the control of onchocerciasis and lymphatic filariasis (see these terms). [rarediseases.oscar.ncsu.edu]
Treatment Antiparasitic treatment Diethylcarbamazine (DEC) is the only macrofilaricide available but is contra-indicated in: Patients with microfilaraemia > 2000 mf/ml (risk of severe encephalopathy, with poor prognosis). [medicalguidelines.msf.org]
Serious complications due to loiasis have included cardiomyopathy, encephalopathy, nephropathy, and pleural effusions. [med-chem.com]
- Neglect
I'm a scientist at the Center for Neglected Tropical Diseases in the Department of Tropical Disease Biology at the Liverpool School of Tropical Medicine, UK. [hstalks.com]
PLoS Neglected Tropical Diseases 5, e1210.CrossRefGoogle Scholar [cambridge.org]
This adds to the evidence that loiasis is not a benign disease and deserves to be included in the WHO's list of Neglected Tropical Diseases. [unboundmedicine.com]
Loiasis should be considered for inclusion in the WHO's list of neglected tropical diseases. FUNDING: Drugs for Neglected Diseases initiative. Copyright © 2017 Elsevier Ltd. All rights reserved. [ncbi.nlm.nih.gov]
- Irritability
She presented to the emergency department with complaints of foreign body sensation, irritation, and described the feeling of something moving in the left eye. [eyetube.net]
Eye involvement can cause burning and irritation of the eye. In long-term residents of endemic areas, infection can be asymptomatic despite large numbers of microfilariae in the blood. [visualdx.com]
This might occur in red, irritating swellings under the skin called Calabar swellings. These swellings might keep going for 2-3 days. The entry over the eyeball can be detected, but it normally takes just 15 minutes. [drscabies.com]
- Vertigo
Post-treatment reaction was defined by the occurrence of symptoms (fever, pruritus, angio-oedema, malaise, hypotension, fatigue, vertigo, headaches, joint or muscle or abdominal pain, central nervous system manifestations) within the 24 h following ivermectin [bmcinfectdis.biomedcentral.com]
Workup
[…] affecting humans and animals, caused by filariae; ie, nematode parasites of the family Filariidae. [1] Filarial parasites can be classified according to the habitat of the adult worms in the vertebral host, as follows (see Pathophysiology, Etiology, and Workup [emedicine.com]
Microbiology
- Wuchereria Bancrofti
The filarial parasite Loa loa overlaps geographically with Onchocera volvulus and Wuchereria bancrofti filariae in central Africa. [ncbi.nlm.nih.gov]
Korean Journal of Parasitology Detection and discrimination of Loa loa, Mansonella perstans and Wuchereria bancrofti by PCR-RFLP and nested-PCR of ribosomal DNA ITS1 region. [lymphedemapeople.com]
bancrofti, Mansonella perstans and Plasmodium falciparum using mosquito carcasses and faeces: A pilot study in Cameroon. 62 Pryce J...Reimer L 36322515 2022 11 A large case series of travel-related Mansonella perstans (vector-borne filarial nematode) [malacards.org]
Other Pathologies
- Tissue Nematode
Filariasis, Loa loa (Pathogen – Tissue Nematode) Organism: Loa loa, the African eye worm, was first noted in the eye of a Negro girl in the West Indies in 1770. [med-chem.com]
nematode) parasites transmitted by Chrysops flies (commonly known as the mango fly or mangrove fly). [emedicine.medscape.com]
Treatment
Treatment Diethylcarbamazine For heavy infections, initial treatment with albendazole and/or apheresis Treatment of loiasis is complicated. Diethylcarbamazine (DEC) is the only drug that kills microfilariae and adult worms. [merckmanuals.com]
Albendazole may also be used as adjunct therapy in cases refractory to multiple treatments with DEC. [eyewiki.aao.org]
[citation needed] Treatment[edit] Treatment of loiasis involves chemotherapy or, in some cases, surgical removal of adult worms followed by systemic treatment. [en.wikipedia.org]
Treatment Treatment includes surgery to remove to worm from the eye or skin. [lymphedemapeople.com]
If microfilaraemia or symptoms persist, a second treatment is given 4 weeks later. [medicalguidelines.msf.org]
Prognosis
Treatment Antiparasitic treatment Diethylcarbamazine (DEC) is the only macrofilaricide available but is contra-indicated in: Patients with microfilaraemia > 2000 mf/ml (risk of severe encephalopathy, with poor prognosis). [medicalguidelines.msf.org]
Outlook / Prognosis What can I expect if I have loiasis? Many people who have loiasis don’t know they have it, and may not have serious health problems from it. If you have symptoms or suspect you have loiasis, talk to your provider. [my.clevelandclinic.org]
Vitreous Chamber One case report of L. loa in the vitreous was effectively treated with vitrectomy with steroid cover.[37] Prognosis Visual acuity is generally not affected by the presence of adult worms in the subconjunctiva, and lasting tissue damage [eyewiki.aao.org]
Prognosis The prognosis in filariasis is good if infection is recognized and treated early. Filarial diseases are rarely fatal, but the consequences of infection can cause significant personal and socioeconomic hardship for those who are affected. [emedicine.com]
Etiology
ETIOLOGY: Loiasis is distributed throughout West and Central Africa. It is transmitted by the mango fly, Chrysops dimidia or Chrysops silacea. The fly bites only in the daytime and humans are the only important reservoir for this filariae worm. [acadderm.com]
Congo, Equatorial Guinea, Ethiopia, Gabon, Nigeria, and Sudan.[9] GeoSentinel Surveillance Network data indicate that travelers to endemic regions are more likely to contract Loa loa infection if their duration of exposure is greater than one month.[10] Etiology [eyewiki.aao.org]
(See Pathophysiology and Etiology.) [13] As with most helminths, adult filarial parasites replicate in a definitive host. The adult worm burden in an individual cannot increase unless the host is exposed to additional microfilaria. [emedicine.com]
Epidemiology
METHODS: Rapid assessment surveys were conducted between 2004 and 2005 using both rapid epidemiological mapping of onchocerciasis (REMO) and rapid assessment procedure for loiasis (RAPLOA). [ncbi.nlm.nih.gov]
Rapid Epidemiological Mapping of Onchocerciasis (REMO) was conducted in the state in 1996 and annual mass ivermectin distribution started in 2000 and it is still ongoing. [journals.plos.org]
Pathophysiology
The pathophysiological mechanisms are discussed in the light of these observations and the few other comments on this subject published in the literature. [ncbi.nlm.nih.gov]
The consequences for the affected individuals or populations as well as the pathophysiological consequences of correlating eosinophilia are largely unknown. [unboundmedicine.com]
Pathophysiology The filarial life cycle, like that of all nematodes, consists of 5 developmental (larval) stages in a vertebral host and an arthropod intermediate host and vector. [emedicine.com]
An understanding of the pathophysiology of these post-treatment reactions is necessary in order to develop strategies to prevent these reactions in the future. [clinicaltrials.gov]
Prevention
Identifying co-endemic areas for major filarial infections in sub-Saharan Africa: seeking synergies and preventing severe adverse events during mass drug administration campaigns. [eyewiki.aao.org]
Prevention DEC 300 mg po once/wk can be used to prevent loiasis. Using insect repellents (including permethrin -impregnated clothing) and wearing long-sleeved and long-legged clothing may reduce the number of bites by infected flies. [merckmanuals.com]
For a description of CDC’s information for preventing insect bites, see CDC’s Yellow Book. [globalinfoonline.com]
Prevention While there are no vaccine s available to prevent people from being infected. Diethylcarbamazine (DEC) 300mg taken once a week is effective at preventing loiasis in long-term travelers to affected areas. [lymphedemapeople.com]