Poliomyelitis is a serious disease caused by a viral infection. The disease is severe, occurs mainly with damage to the central nervous system. It leads to a variety of consequences, and therefore it is important to detect it in time and start treatment.
Diagnosis of poliomyelitis involves a series of studies. They should be described in more detail, and also a little attention should be paid to the causes, symptoms and possible consequences of this ailment.
Briefly about the disease
Before discussing the principles of diagnosis of polio, it is necessary to study the specifics of this ailment. This is the enterovirus infection that polioviruses cause. They affect motor neurons of the anterior horns of the spinal cord. This effect leads to serious paralytic complications with subsequent disability of the patient.
As a rule, the disease affects children whose age is less than 4 years. They account for 60-80% of cases.
The last epidemic occurred in the middle of the last century. In the late 80s, WHO adopted a resolution whose goal was the elimination of the disease worldwide.
To date, in countries where preventive vaccination against poliomyelitis is carried out, the disease occurs in the form of sporadic isolated cases. These are India, Afghanistan, Syria, Nigeria, Pakistan. Our country, as well as North America and the countries of Western Europe are free from polio.
Causes
This disease is caused by antigenic types of poliovirus, which belong to the genus enteroviruses. There are three of them. But the virus of the first type carries the greatest danger - it accounts for 85% of cases. It is very tenacious, can last up to 6 months in feces and up to 100 days in water.
It tolerates even freezing and drying; antibiotics and digestive juices do not affect it. The virus can die only as a result of the following effects:
- Heating and subsequent boiling.
- Disinfectant treatment.
- UV exposure.
The source of the virus can be not only an infected person. An asymptomatic carrier can spread it. He himself may not have polio. However, it will spread through its nasopharyngeal mucus and bowel movements. The virus is transmitted by fecal-oral, airborne and contact routes.
Once in the body, it is introduced into the cells, as a result of which the synthesis of protein and nucleic acids is disrupted. The result is destructive and dystrophic changes. The complete death of a neuron is possible. The consequence of the destruction of 1 / 3-1 / 4 of nerve cells is the development of complete paralysis and paresis.
Symptoms
Before proceeding to a discussion of the diagnosis and treatment principles of polio in children and adults, it is necessary to list the symptoms that indicate the development of such a specific ailment.
The incubation period lasts 8-12 days. If an inapparent form develops, then clinically the disease does not manifest itself. It is discovered only as a result of laboratory research.
An ailment of the visceral form is manifested by intoxication, fever, diarrhea, abdominal pain, moderate catarrhal phenomena. The disease ends approximately 3-7 days after the symptoms are felt. No residual neurological manifestations are observed.
The most severe is a paralytic disease. There is dyspepsia, tracheitis, pharyngitis, rhinitis, pain in the limbs and spine, 2-wave fever, convulsions, confusion. On the 3rd-6th day, the paralytic phase begins. By the end of the second week, the vital centers of the medulla oblongata are affected, paralysis of the diaphragm and respiratory muscles is possible.
Diagnostics
Having considered the causes, symptoms and types of polio, you need to pay attention to this topic. This serious rare ailment is usually suspected by a pediatric neurologist or pediatrician. The basis for the assumptions is the anamnesis, diagnostically significant symptoms and epidemiological data.
There are certain difficulties. Not all doctors immediately prescribe an analysis for polio, since this particular ailment is not always suspected. Often mistakenly diagnosed with serous meningitis, acute intestinal infection, acute respiratory viral infection, influenza.
Laboratory tests can help to accurately determine the disease, which will be described in detail below. Now we need to discuss other methods.
It is important to differentiate the virus, and therefore a polymerase chain reaction is carried out. Still often prescribed lumbar puncture. When conducting it, cerebrospinal fluid flows under high pressure. During the study, it is possible to identify its colorlessness, transparency, as well as an increased content of glucose and protein. After electromyography, it is possible to confirm the lesion at the level of the anterior horns of the spinal cord.
Talking about the methods for diagnosing poliomyelitis, it should also be noted that the disease must be differentiated in time with botulism, myelitis, Guillain-Barré syndrome, serous meningitis, tick-borne encephalitis and polio-like diseases.
Virological method
It is applicable in the diagnosis of polio without fail. It is very important to isolate the virus and identify it. As a biomaterial, feces of the patient are necessary. A little less often take cerebrospinal fluid, blood and nasopharyngeal flush.
The material is first filtered and then subjected to antibiotic treatment. Then it is introduced into the cell culture of Hep-2 and RD (from human rhabdomyosarcoma). After about 5-7 days, the cytopathic effect of viruses (CPS) occurs, which manifests itself in the form of fine-grained cell destruction.
Identification of the virus is carried out in a neutralization reaction. This means that a virus connected to three types of polyvalent anti-poliomyelitis serum is introduced into tissue culture. This is the first stage. The next step is the management of the virus with individual sample sera that are monovalent. What is the result? If the serum and virus type are identical, then the CPP is not observed.
Serological method
It is also used to diagnose poliomyelitis. It helps to determine if the titer of antibodies in the blood of ill patients is increasing.
For this, a neutralization reaction with paired sera, which were obtained during the acute stage of the disease, as well as at the time of convalescence, is used in tissue culture.
Enzyme-linked immunosorbent assay (ELISA), as well as complement fixation reaction (CSC). In the case of a positive result, it is possible to determine a 4-fold increase in antibody titer in the 2nd serum, when compared with the 1st.
What is it - ELISA analysis? Actively developing area of chemical enzymology. This is a method with a unique specificity of the immunochemical reaction. Simply put, antibodies only bind to specific antigens. IFA has been widely introduced into various medical fields, since the reagents used are stable, the registration methods are simple, and the cost of conducting is quite low.
Forms of the disease
Speaking about the diagnosis of poliomyelitis in children and adults, it is necessary to make a reservation that the notorious differentiation is always carried out on the basis of symptoms. And each form of the disease is individual. The following list can be distinguished:
- Meningeal form. Manifestations: severe pain, stretched roots of the spinal nerves and nerve trunks, their pain on palpation.
- Spinal form. Manifestations: gentle, non-paretic gait, preservation of muscle tone, discomfort in the joints with passive movements, increased deep reflexes, inflammatory changes in the blood. This disease is often confused with polyradiculoneuritis, diphtheria polyneuropathy, spinal amyotrophy Werdnig-Hoffmann.
- Polio form. The pathological process is diagnosed in the cervical segments. Manifestations: paralysis of the muscles of the shoulder girdle and neck, flaccid paresis, lymphocytic pleocytosis (insignificant, 40-60 cells), increased protein level (approximately 0.66-1.0 g / l). When studying the studied material in the laboratory diagnosis of poliomyelitis, doctors take into account the epidemiological history. This may be the use of raw milk, a tick bite, etc.
- Diphtheria form. Manifestations: the symmetry of the lesions, the slow growth of paresis over several weeks, the detection of violations of bioelectric activity in the process of electroneuromyography. Diagnosed after 1.5-2 months after diphtheria.
- Polyradiculoneuritis. Manifestations: slow development and further increase in symmetrical paresis, sensitivity disorder in the radicular and polyneuritic types, an increased amount of protein in the cerebrospinal fluid.
- Pontic form. Manifestations: a decrease in taste sensitivity to salty and sweet, lacrimation on the affected side, pain of trigeminal points felt during palpation, impaired facial sensitivity and spontaneous pain.
- Bulbar form. Manifestations: convulsive syndrome and deep disorders of consciousness. It is important to differentiate it with stem encephalitis.
As part of the topic regarding the differential and microbiological diagnosis of poliomyelitis, it should be noted that lesions of the nervous system, which are not clinically different from the disease in question, often cause Coxsackie-ECHO group enteroviruses. In such cases, the whole range of serological and virological diagnostic methods and the PCR method mentioned earlier are used.
Specific prophylaxis
Above we talked about the features of the disease, the main method of laboratory diagnosis and what ELISA analysis is. This is all important, but now it’s also worth talking about the specific prophylaxis carried out by killed and live vaccines.
The method is interesting. The killed vaccine contains polio viruses of the 3rd, 2nd and 1st types. They are grown in monkey kidney tissue. A killed vaccine provokes humoral immunity - the formation of IgM and IgG. But at the same time, it does not interfere with the reproduction of viruses that occurs in the cells of the intestinal mucosa.
Live vaccines of types 3, 2 and 1 are formed from attenuated strains, which are also cultivated in the kidney cells, but only in other animals - green African monkeys.
In addition to the notorious IgM and IgG antibodies, it induces secretory IgA. This process occurs in the mucous membrane of the gastrointestinal tract (small intestine, to be precise). And they are the antibodies against polio that prevent the circulation of wild strains.
Vaccine
In the vast majority of hospitals in the CIS countries, an oral vaccine is common . Vaccination is done simply: the drug described above is instilled into the oral cavity.
Perform this after the child is 3 months old. Next, you need to do two more vaccinations. The interval between them is 1.5 months. It turns out that the baby will need to be attributed to the doctor when he is 4 and 6, respectively. Revaccination is carried out at 18 and 20 months, and then only at 14 years.
One must be warned that after the introduction of weakened viruses into the body, the so-called vaccine-associated polio is able to develop. The probability is very small, but there is. Most often, the disease develops in infants after their first vaccination. What is the reason? Usually - reduced immunity or spontaneous mutation of the virus in a child’s body.
And by the way, since after vaccination the baby becomes a potential carrier of the virus, not vaccinated people, but also those whose immunity is suppressed, can become infected from it.
Treatment
A little attention should be paid to clinical recommendations. Manifest poliomyelitis is always treated permanently. The patient is shown isolation, rest, a high-calorie diet and bed rest.
It is very important to give the limbs the correct physiological position. Chest massage and pressure sore prevention are needed. If the patient has dysphagia, then nutrition is organized through a nasogastric tube. In case of violation of spontaneous breathing, mechanical ventilation is indicated.
Unfortunately, no specific treatment has been developed. Vaccines, the features of which were discussed above, prevent the development of the disease, preventing it from developing (development of immunity). But they do not cure polio. And therefore conduct pathogenetic and symptomatic therapy.
Prescribe the intake of ascorbic acid, B vitamins, dehydrating and painkillers, respiratory analeptics, neostigmine, etc.
In the recovery period, time is devoted to rehabilitation measures. Namely:
- Physiotherapy.
- UHF
- Treatment in sanatoriums.
- Orthopedic massage.
- General healing baths.
- Paraffin treatment.
Treatment and prevention of children is always carried out with the direct participation of a pediatric orthopedist. If the risk of developing contractures is identified, then the imposition of a splint, plaster casts, orthopedic tires, as well as wearing special shoes are prescribed.
There is always the possibility of residual effects. Their treatment usually includes tendon-muscle plastic surgery, tenomyotomy, arthrosis, tenodesis, resection and further bone osteotomy, surgical scoliosis correction, etc.
Complications and Predictions
We can not talk about the danger of polio. This disease often leads to disability. If the paralyzed limbs begin to move, then they remain deformed - they are shortened, and the muscles atrophy.
The pathological process can affect the respiratory system, and this is fraught with respiratory disorders, because of which a person can even die (suffocate).
Mild forms of the disease usually pass without a trace. And due to the targeted long-term vaccine prevention, only abortive and inapparent forms of infection prevail in the structure. They are treated successfully. Paralytic forms affect only people who are not vaccinated against polio. And this is a mandatory prevention.
If you suddenly suspect that the child has contracted polio, they immediately isolate him, and they disinfect them in the premises where he was. Persons with whom he was contacted are placed under surveillance, as well as immunization of OPV out of turn.