Table of contents:
- Life cycle and routes of infection
- Disease stages and symptoms
- Pathology treatment
Filariasis (aka elephantiasis and filariasis) is a helminthic common form of infection (invasion). Its causative agent is filaria, a filamentous whitish worm with a very long length (up to 10 cm). Filariasis in humans is often found in tropical latitudes, countries in Africa, southern Asia, Oceania and South America. In total, the number of people suffering from filariasis in the world exceeds 120 million.
- Life cycle and routes of infection
- Disease stages and symptoms
- Pathology treatment
Life cycle and routes of infection
Filariasis is not one disease, but a number of pathologies (onchocerciasis, mansonellosis, etc.).
Filariae end up in the human body after being bitten by a winged carrier (horsefly, midge, mosquito). It's easy to catch filariasis from mosquitoes. By the way, the larvae enter the body of these insects in the same way. A mosquito or midge bite an infected person, in whose body the larvae of filariae are concentrated under the skin, and become carriers of the life-threatening parasites of helminths.
Disease stages and symptoms
When an insect bites a person, the larvae enter the human bloodstream and they have:
- Ripening period. It differs from person to person. In some cases (when a person has a weak immune system), parasites "mature" for several months, in others - more than six months.
- When filarial worms become adults, the carrier stage begins. Filariae only lay larvae, which enter the human bloodstream.
- Blockages develop after 3-5 years when adult filarias:
- penetrate the organs of the reproductive system;
- make their way into the lymph nodes and lymphatic vessels (most often the lower extremities, but also the mammary glands, or scrotum);
- settle in the eyeball, eyelid and various cavities (including the abdominal).
Filariasis begins after adult filarias completely occupy the lymphatic vessel. Its blockage occurs.
Symptoms of filariasis vary depending on how far the disease has gone, as well as on its location:
At the initial stage (when the larvae just entered the bloodstream and began to gradually "settle" in a particular area of the body):
- the skin becomes covered with sores and swelling that form due to problems with lymph drainage. This is an allergic reaction to the invasion of "small" microfilariae into the subcutaneous area, an attempt to get rid of them and from the toxins formed in the course of their vital activity. If treatment is not started on time, atrophy and premature aging of the affected skin areas may occur;
- fever begins, body temperature rises slightly. With the help of an increased temperature, the immune system tries to destroy uninvited guests, to destroy individuals;
- the allergic form of bronchitis begins to pester, a cough and spasm appears;
- the volume of the lymph nodes increases. It does not cause painful sensations at the onset of the disease;
- men have problems with the genitourinary system. Funiculitis (inflammation of the spermatic cord) develops, as well as hydrocele (dropsy of the testicle) and orchiepididymitis (inflammation of the epididymis and itself). Filariasis of the genitourinary organs is most often manifested in men;
- women develop mastitis (inflammatory pathology of the mammary glands);
- the synovium in the joint becomes inflamed (synovitis). It becomes difficult to move the joint.
In the second stage (carrier):
- lymph nodes become very inflamed (especially in the groin and thighs). Lymphadenitis begins, leading to compression of the lymphatic vessels. It is accompanied by vomiting, migraine and lack of strength;
- lymphangitis develops (lymphatic vessels become inflamed). The lymph ceases to flow normally, in the area of inflammation there is a pathological proliferation of connective tissue. If the pathology is started, the lymphatic capillaries can rupture, and the lymph will end up in the cavity of the inflamed organ;
- whole colonies of filarias accumulate under the skin. They are shaped like flexible knots that roll over like waves. Accumulations may begin to fester. An intractable ulcer is formed from them;
eyes are affected. Parasites can be found in the eyelids, in the middle of the eyeball, or under the conjunctiva. Symptoms of eye filariasis include severe lacrimation, fear of light, and conjunctivitis. Pain appears when a person moves his eyes, opens them and closes them. Uveitis with filariasis - inflammation of the blood vessels of the eyes - is a common occurrence. Clouded areas form in the iris, and a clear liquid accumulates under the conjunctiva. Without treatment, eye damage from filariasis can result in blindness.
At the last third (clogging) stage:
the so-called elephantiasis (elephantiasis) develops. The extremities (almost always the lower ones) or individual areas of the body (most often the genitals or eyelids) become many times larger due to the fact that lymph stagnates and the lymphatic vessels are inflamed. Fatty tissue begins to grow uncontrollably, gradually turning into connective tissue. A large number of papillomas and ulcers appear on the skin, it becomes thinner, covered with wrinkles and age spots. The person is constantly tormented by fever, sometimes there is a weight loss of the upper limbs;
- lymph appears in the urine (hiluria);
- ascites develops (lymph in large quantities is in the abdominal cavity);
- if the pathology continues not to be treated, pneumonia will begin;
- in cavities filled with pus (lymph), bacteria multiply, inflammation develops. It ends with an abscess through which the lymph flows out. Scar-like scars remain on the skin.
To diagnose filariasis, the doctor performs a thorough examination of the patient. He also finds out whether the patient has visited countries with a hot climate in the past few years, whether he has been bitten by insects, carriers of infection. If the doctor detects external symptoms of the disease (pigmentation, edema, inflammation), then to make sure that it is elephantiasis, and not any other, he prescribes the following diagnosis:
- Mazzotti test (provocation with diethylcarbamazine). For the filariae to be found, the patient takes (once) 50-70 mg of diethylcarbamazine. This agent "expels" parasites into the area of superficial capillaries, where they are much easier to identify. Approximately one to one and a half hours after taking the drug, the patient donates blood for analysis;
- Ultrasound. Ultrasound can show if there are filarias in the subcutaneous area if it is thickened;
- puncture (in the area of the subcutaneous nodes). The sample is taken using a special needle. If a person is sick with filariasis, cells of histiocytes, erythrocytes and granular substance will be found in it;
- unchanged drop. This is a special blood test. The doctor takes 0.3 ml of blood from the patient's finger. If a person's disease has already gone quite far, this analysis will detect it;
- microcapillary method. The blood is placed in thin tubes called "capillaries". They "run" it through a centrifuge to separate the plasma, in which the parasites can then be easily identified;
- sedimentation and membrane filtration. Helps to detect filariae at the very start of pathology;
- study of unfortified and fortified preparations. A small piece of the skin is cut off with a scalpel and viewed under a microscope.
The patient should also pass an ELISA test to detect fragments of bacteria and other substances that are of a protein nature.
For filariasis, the doctor prescribes:
- Anthelmintic therapy. Anti-parasite medications usually work after the first dose. Most often, the doctor prescribes Albendazole, Ditrazine Citrate or Invermectin. Treatment of filariasis with Piperazine also gives results.
- Medicines for the treatment of concomitant infections. Antibiotics are prescribed not only to remove bacteria, but also to slow down the reproduction of filarial parasites. For this, doxycycline is usually prescribed. It is necessary to take the remedy for 2 months.
Anti-inflammatory drugs. They are used if the patient's disease has caused a strong allergic reaction, as well as if trophic changes occur in the tissues. To eliminate the problem, hormonal agents are prescribed: Dexamethasone, Hydrocortisone, Loratadin. The dosage of drugs and the duration of their administration is determined by the doctor. During pregnancy, you should use them with extreme caution.
- If the patient's allergy is very severe, glucocorticosteroids are recommended. Most often, prednisone is prescribed by a doctor.
- Desensitizing therapy. Desensitizing agents are used to eliminate excruciating burning and itching on the surface of the skin. To do this, use tablets of the antihistamine group - Loratadin, Cetrin, Suprastin and some others.
If the pathology is in its late stages, and it cannot be removed with medication, the specialist prescribes a surgical intervention.
This is how doctors eliminate abscesses, achieve lymph drainage and return a normal appearance to the affected area of the body:
- with the help of a surgical operation, it is really possible to remove filariasis, which is located in the muscle and subcutaneous region. To restore the normal outflow of lymph, the doctor removes the affected part of the lymphatic vessel and sutures what is left with a vein;
- to eliminate the focus of the disease in the eye, a vitrectomy is performed (removal of the vitreous humor). It is replaced with a kind of prosthesis - silicone oil. So the patient manages to save his sight;
- to remove the focus of filariasis in the abdominal cavity, it is punctured and the accumulated pus is pumped out;
- to remove dropsy of the testicles, make a puncture or incision;
- to remove an abscess, an incision is made, and then the resulting cavity is washed with antibiotics. Also, the abscess is excised.
The simplest and most reliable prevention of filariasis is repellents and the use of various other insecticidal agents. They kill or drive away parasite-carrying insects. This can prevent the appearance of lymphatic filariasis and the development of elephantiasis.
Filariasis is definitely a serious and very dangerous disease. Only a quick diagnosis and treatment can protect against its unpleasant symptoms and consequences.