What is Brugios?
Brugios (lat. Brugia – a genus of helminotes filarias) is a parasitic disease caused by filamentous worms – filars, the larvae of which circulate in the blood, and adults infect the lymphatic system.
Causes of Brugiosa
The causative agent of Brugiosa, Brugia malayi, is a helminth nematode that has an elongated threadlike shape with thinning at the ends. The length of the parasites is 22-100 mm, width 0.1-0.3 mm. The development of filarias takes place with the change of owners, the final owner of Brugia malayi is a man and some species of monkeys, the intermediate owners are various species of mosquitoes of the genera Culex, Aedes, Mansonia, Anopheles. Mature filarial parasites in the lymph nodes and vessels.
The helminth females give birth to larvae – microfilariae, which in the human body do not change morphologically and do not grow. Microfilariae have a length of 0.127-0.32 mm, width – 0.005-0.1 mm. They parasitize in the circulatory system.
Brugia malayi is found in China, India, Indonesia, Korea, Japan, Malaysia and the Philippines.
Brugia malayi has two strains – periodic and subperiodic.
Periodic variety is more common, it is infected near rice paddies, and subperiodic – in forests.
Along with people, Brugia malayi can hit cats.
In Indonesia, another type of pathogen is common – Brugia timori.
A periodic strain of Brugia malayi is peculiar only to humans, while subperiodic occurs in monkeys. Both strains of Brugia malayi are characterized by the nocturnal peak of microfilariaemia, which occurs much less frequently in a periodic strain.
Adults filarias can parasitize in the human body for a long time (up to 12, and according to some data – up to 17 years), microfilariae – about 12 months.
Pathogenesis during Brugiosa
The source of brughosis is man and some monkeys. The direct carriers of infection are mosquitoes.
The causative agent of Brugiosa (Brugia malayi) is transmitted by various species of mosquitoes of the genera Mansonia and Anopheles. The development of microfilariae in mosquitoes lasts 8-35 days, depending on the ambient temperature. When a mosquito bites, invasive forms of microfilariae enter the skin, are actively implanted in the bloodstream and are brought into the tissues by blood flow. The transformation of microfilariae into mature forms occurs 3-18 months after they enter the human body.
Brugioz is common in Asian countries: in India, on Fr. Ceylon, in Thailand, Vietnam, Laos, Cambodia, China, Japan, Indonesia, Malaysia.
The basis of the pathogenesis of Brugosis is toxic-allergic reactions, the mechanical effect of helminths on the lymphatic system and secondary bacterial infection. Like many other helminthiasis, brugioz in some cases may not give a pronounced clinical picture. Sometimes there are no clinical manifestations of invasion at all. Asymptomatic broids occur in cases where the parasites do not clog the lymphatic vessels and do not cause inflammatory changes in the surrounding tissues. Patients with such forms of infection are detected by chance when they detect microfilariae in peripheral blood.
The bruises in the lymphatic vessels, including the thoracic duct, are interwoven into tangles that cause lymph flow and lymphostasis to slow down. Parasites cause inflammatory sealing of the walls of the lymphatic vessels, which ultimately leads to blockage of blood vessels as a result of stenosis or thrombosis. Thrombosed lymphatic vessels often rupture. Due to prolonged lymphangitis and lymphadenitis, elephantiasis (elephantiasis) can develop in various parts of the body. Modified endothelium of lymphatic vessels, foci of necrosis in lymph nodes and surrounding tissues are favorable places for the development of coccal infection with the formation of abscesses. As a result of the vital activity of parasites and, especially, when they decay, substances are formed that lead to the sensitization of the body with local and general allergic reactions – eosinophilia, skin rashes, etc.
Symptoms of Brugiosa
Allergic manifestations may develop approximately 3 months after infection. Microfilariae detected in the blood no earlier than after 9 months. The disease begins with various allergic manifestations. On the skin, especially on the hands, painful elements like exudative erythema appear, lymph nodes increase in the inguinal areas, on the neck and in the armpits, painful lymphangitis, funiculitis, orthoepididymitis, and synovitis with outcome in fibrous ankylosis often occur, and in women – mastitis. With long-term recurrent funiculitis and orchepididymitis occurs hydrocele. Fever is characteristic, bronchial asthma and bronchopneumonia are often developed. After 2-7 years after infection, the disease enters the second stage, which is characterized mainly by lesions of the cutaneous and deep lymphatic vessels with the development of varicose dilatation, impaired lymph flow, and rupture of these vessels. There are painful lymphangitis with regional lymphadenitis. At this time, for several days, the patient has marked symptoms of general intoxication due to high body temperature and severe headaches. Often there is vomiting, sometimes delirious state develops. The attack usually ends with profuse sweating. As a result of ruptures of the lymphatic vessels, lymph flow and a decrease in the intensity of lymphadenitis are observed.
Phases of relative well-being are periodically replaced by regular exacerbations of the disease. In place of lymphangitis there are dense yarns, the affected lymph nodes are also subjected to fibrous compaction. Characteristic is an increase in the inguinal and femoral lymph nodes. Initial swelling of the lymph nodes does not cause pain, however, with the subsequent development of lymphangitis, severe pain appears in the nodes. The lesion can be one- or two-sided, the size of the nodes from small to 5-7 cm in diameter. Often, the so-called lymphoscultum (chylous soaking of tunica vaginalis) and chyluria develop in parallel. Lymphocrotum is clinically manifested by an increase in the scrotum. When palpation of the skin of the scrotum, dilated lymphatic vessels are easily detected. When these vessels rupture a large amount of rapidly coagulating lymph flows. Lymphatic leakage from damaged vessels may last for several hours.
In countries of North Africa, India and China, chyluria or lymphuria is common in patients with broids. The patient notices that the urine has acquired a milky white hue. In some cases, the urine becomes pink or even red, sometimes it is white in the morning and red in the evening or vice versa. The presence of blood in the urine along with lymph is apparently explained by the ruptures of the small blood vessels of the dilated lymphatic vessels. Microfilariae are detected in the urine only at night. Sometimes this is preceded by a slight pain over the pubis or in the groin areas. A characteristic is the retention of urine due to coagulation of the lymph and the formation of flakes in the urinary tract. In lymphuria in the urine there is an admixture of lymph, protein in a significant amount, possible admixture of blood, but there is no trace of fat. Lymphocytes are found in urine sediment.
The bodies of the dead filarial usually dissolve or calcine without a trace. However, in some cases, dead parasites cause the development of abscesses, which lead to severe complications, such as empyema, peritonitis, purulent inflammation of the genitals.
The third (obstructive) stage of the disease is characterized by elephantiness. In 95% of cases, ivory of the lower extremities develops, more rarely – the upper extremities, genitals, certain parts of the body and very rarely the face. Clinically, elephantiasis is manifested by rapidly progressing lymphangitis with the addition of dermatitis, cellulitis in combination with fever, which in some cases may be the main symptom of the disease and is a consequence of the addition of a bacterial infection. The skin over time becomes covered with warty and papillomatous growths, there are patches of eczema-like skin changes, non-healing ulcers. The legs can reach enormous sizes, they take the form of shapeless lumps with thick transverse folds of the affected skin. The weight of the scrotum is usually 4-9 kg, and in some cases up to 20 kg, a case is described when the patient’s scrotum weight reached 102 kg. In the case of facial elephantiness, the upper eyelid is more often affected. In Brugiosa, elephantiasis usually occurs only on the limbs, the lesion is often one-sided, the skin remains smooth.
Diagnosis of Brugiosa
The diagnosis and differential diagnosis of Brugosis is based on epidemiological data and the characteristic clinical picture of the disease (allergic manifestations in the early stage of the disease, damage to the lymphatic system, and finally the development of elephantiasis in the third stage of the disease).
The final confirmation of the diagnosis is the detection of microfilariae in the blood. Blood for analysis must be taken at night. When viewed under a cover glass of a fresh drop of blood at low magnification of the microscope, mobile microfilariae are easily detected. To establish the type of microfilariae, blood products (smears or drops) stained according to Romanovsky are examined. In the third stage of the disease, the concentration of microfilariae in the blood is negligible. In these cases, enrichment methods are used (Bell filtration or concentration). One ml of venous blood is added to 9 ml of a 2% formalin solution in distilled water, the mixture is centrifuged for 3-5 minutes, and the resulting precipitate is examined under a microscope. Used and more complex methods of enrichment. In Hiluria, microfilariae can sometimes be detected in the urine.
Albendazole (albendazole), a broad-spectrum anthelmintic drug, is recommended in combination with ivermectin for the treatment of brugosis (elimination of mature stages) outside the United States. The combination of albendazole and diethylcarbamazine is also effective.
Prevention comes down to a healthier population (screening and de-worming) and vector control.