Echinococcosis of the lungs
Causes and symptoms of pulmonary echinococcosis
What is pulmonary echinococcosis?
Like all types of echinococcosis, pulmonary echinococcosis is a cystic stage in the development of a tapeworm. The final owner of such a worm is domestic dogs and cats and wild arctic foxes and foxes. As for the intermediate hosts, or carriers of the cystic stage of development of echinococcus, their role is played by large and small ruminants, rabbits, pigs, monkeys and humans.
Echinococcosis of the lung has a hydatid or unicameral form. In terms of the incidence of the disease, pulmonary echinococcosis is in second place after liver echinococcosis. As for its distribution, pulmonary echinococcosis is widespread throughout the world. If we turn to the statistics, it says that the most common echinococcosis of the lungs has in South America, North Africa, New Zealand, Australia, Southern Europe, and Yugoslavia. If you move from south to north, then the defeat of echinococcosis decreases. Also, quite often it is found in countries where animal husbandry is widely developed, and mainly sheep breeding. These countries include the North Caucasus, Kazakhstan, Kyrgyzstan, Uzbekistan, Moldova, Tatarstan.
An echinococcal cyst is a bladder that has a rather complex structure. The outer shell of such a bladder is a cuticle; in some cases, its thickness is 5 mm. Under this shell is the inner embryonic membrane, or, in other words, germinal. This shell promotes the formation of brood capsules with scolexes, daughter bubbles, as well as the growth of a layered shell.
Causes of pulmonary echinococcosis
In humans, the causative agent of pulmonary echinococcosis is the larval stage of the echinococcal tapeworm Echinococcus granulosus. The form of sexually mature echinococcus is a small cestode, the length of which is 2.5–5.4 mm, the width is 0.25–0.8 mm. It consists of a neck, a pear-shaped scolex and 3-4 segments. The scolex has a crown of two rows of hooks (28-50) and four suction cups.
The echinococcus chain is a sexually mature form and parasitizes exclusively on animals such as wolves, dogs, jackals, foxes, they are also the final hosts. Echinococcal cyst is the larval stage of echinococcosis. It infects intermediate hosts, herbivores and omnivorous ungulates.
Oncospheres are able to withstand high temperatures - from –30 ° C to +38 ° C - and retain their viability, being on the soil surface without sunlight and at temperatures from 10 to 26 ° C.
A person can become infected with echinococcosis of the lungs through contact with a dog. In a dog, eggs and segments of the echinococcosis tapeworm can be found on the tongue and wool.
Healthy animals can also be mechanical transmitters of eggs, they can also be on the tongue, wool. One should not exclude the fact that a person can become infected through dirty vegetables or fruits, as well as through dirty forest berries. Another source of infection can be hunting wild animals, as well as working with fur and making fur clothing.
Symptoms of pulmonary echinococcosis
Echinococcosis of the lungs has three stages of development:
1. The first stage is the asymptomatic stage. It can continue for many years from the moment the parasite enters the body. In this case, the cyst develops rather slowly, without causing any inconvenience to the patient. It can be found by chance, for example, during an X-ray examination.
2. The second stage is characterized by clinical manifestations. In the presence of this stage, patients suffer from dull pain in the chest, sometimes coughing and shortness of breath may occur. Symptoms begin to appear when the cyst becomes significant.
3. The third stage is the stage characterized by complications. In patients, there is suppuration and infection of the cyst, as well as its breakthrough into the bronchi (approximately 90%), abdominal cavity, biliary tract, pericardial cavity and pleura.
If the cyst is large, then when examining the chest, in some cases, its bulging can be determined.
A rupture of such a cyst may occur, and then scraps of the membranes of the cyst, small daughter bubbles and the contents of the cyst itself are cleared into the bronchi. All this can cause asphyxiation. Also, rupture of the cyst causes a strong and severe anaphylactic shock, because toxic echinococcal fluid is absorbed, it acts on the receptor apparatus.
Quite often, urticarial rashes on the skin may appear. The fluid that pours out of the cyst cavity contains scolexes; when it enters the pleural cavity, they cause seeding and contribute to the appearance of new bubbles.
With echinococcosis of the lungs, a high temperature is also noted, this is due to perifocal inflammation. If cyst suppuration occurs, then the temperature rises to 39 ° C and remains in this position for a long time.
Diagnosis of pulmonary echinococcosis
Diagnosis of pulmonary echinococcosis consists in carrying out the following methods of determination: X-ray and ultrasound examination, scanning, tomography, laparoscopy and serological methods. The main method for determining pulmonary echinococcosis in the population is the mass carrying out of fluorographic determination. Prophylactic examination now allows you to quickly learn about the disease before the first appearance of possible clinical symptoms.
X-ray examination reveals one or more homogeneous shadows in the lung, which have an oval or round shape with a clear and even outline. In some cases, calcification of the fibrous capsule can be determined. If perifocal inflammation develops, then the contours of the cyst shadow become less clear. If the cyst compresses the adjacent bronchi, it can cause atelectasis of the lung tissue.
When making an accurate diagnosis, help:
- enzyme immunoassay: the reaction can be considered positive when evaluated at 2 or 3 plus; - the reaction of indirect hemagglutination.
Echinococcal cysts should be distinguished from peripheral carcinomas, tuberculomas, and other diseases because they produce globular shadows on the lung image.
In diagnostics, all research methods are used, with the exception of puncture.
Prevention of pulmonary echinococcosis
Prevention of echinococcosis of the liver is no different from the prevention of other types of echinococcosis: all dogs that are on the territory of livestock farms are also recorded. It is necessary to fight with stray animals, since they are the main source of infection for everything around. Control consists in eliminating them or registering them on a special account.
Specialists on their farms or farms carry out deworming of all available dogs. Also, this procedure must be carried out with personal dogs.
As for personal hygiene, then you need to wash your hands thoroughly after contact with animals and all kinds of work with the ground. Special attention should be paid to vegetables and fruits, which must be carefully processed before eating. Do not consume raw water from natural reservoirs.
Article author: Mochalov Pavel Alexandrovich | d. m. n. therapist
Education: Moscow Medical Institute. IM Sechenov, specialty - "General Medicine" in 1991, in 1993 "Occupational Diseases", in 1996 "Therapy".
