Trichinosis - Symptoms

The incubation period of trichinosis on average lasts 10-25 days, but can range from 5-8 days to 6 weeks. When infected in synanthropic foci (after consuming infected meat from domestic pigs), there is an inverse relationship between the duration of the incubation period and the severity of the course of the disease: the shorter the incubation period, the harder the clinical course, and vice versa. When infecting in natural foci, such patterns are usually not noted.

Depending on the nature of the clinical course, the following forms of trichinosis are distinguished: asymptomatic, abortive, mild, moderate and severe.

The first symptoms of trichinosis in the form of nausea, vomiting, loose stool, abdominal pain in some patients appear in the coming days after consuming infected meat and can last from several days to 6 weeks.

With asymptomatic form, the only manifestation may be the eosinophilia of the blood. For the abortive form, short-term (1-2 days) clinical manifestations are characteristic.

The main symptoms of trichinosis are fever, muscle pain, myasthenia gravis, edema, hypereosinophilia of the blood.

Fever of remitting, permanent or incorrect type. Depending on the degree of invasion, the elevated body temperature in patients remains from several days to 2 weeks and longer. In some patients subfebrile temperature persists for several months.

Swelling syndrome appears and grows quite quickly - within 1-5 days. With mild and moderate forms of the disease edema persists 1-2 (less often up to 3) weeks, with a severe course edema develops more slowly, but persists longer and can recur. First, as a rule. There is a periorbital edema accompanied by conjunctivitis and then spreading to the face. In severe cases edema passes to the neck, trunk, limbs (an unfavorable prognostic sign). In patients with trichinosis, maculopapular rashes on the skin are observed, sometimes acquiring a hemorrhagic character, subconjunctival and subungual hemorrhages.

The muscular syndrome is manifested by myalgia, which in severe course takes a generalized character, is accompanied by a myasthenia gravis. Pain appears first in the muscles of the limbs, then in other muscle groups, including chewing, tongue and throat, intercostal, oculomotor. In the late stage of trichinosis, muscle contractures can develop, leading to immobility of the patient.

With lung damage that develops during the first 2 weeks of the disease, cough is observed, sometimes with an admixture of blood in the sputum, signs of bronchitis, on the X-rays are determined "flying" infiltrates in the lungs.

In peripheral blood, usually from 14 days, eosinophilia, leukocytosis, hypoproteinemia (reduced albumin content), a decrease in the level of potassium, calcium, an increase in the activity of enzymes (CKK, ACT, etc.) in the blood serum are increasing. Eosinophilia reaches its maximum values at 2-4 weeks and can persist at 10-15% for 2-3 months and longer. There is a definite relationship between the height of eosinophilia and the severity of clinical signs of trichinosis. In patients with severe current, eosinophilia in the peripheral blood may be insignificant or even absent.

Trichinellosis of mild flow is manifested by a slight increase in body temperature (up to 38 ° C), edema of the eyelids. Mild pain in the muscles of the extremities and low eosinophilia.

Trichinosis of moderate severity is characterized by an incubation period of about 2-3 weeks, an acute onset with fever to 39 ° C for 1-2 weeks, edema of the face, moderate pain in the limb muscles, leukocytosis 9-14 × ^{10 9} / L, and eosinophilia 20-25% and higher.

Trichinosis of severe course is characterized by a short incubation period (less than 2 weeks), a prolonged high temperature for at least 2 weeks, generalized edema, which is largely due to accelerated protein catabolism and hypoproteinemia, myalgia with muscle contractures and complete immobility of the patient. In the hemogram - hyperleukocytosis (up to 20x10 ⁹ / l), hypereosinophilia (up to 50% and above), however, in extremely severe cases, eosinophilia may be absent or minor (a poor prognostic sign). Dyspeptic and abdominal pain syndrome is common, more than 50% of patients develop hepatomegaly.

The total duration of the manifest forms of the disease, depending on the severity of the flow, ranges from 1-2 to 5-6 weeks. The period of convalescence in severe form of trichinosis may be 6 months or more. Such symptoms of trichinosis as muscular pain and swelling of the face can periodically recur, accompanied by fever and other signs. Relapses are easier than the primary disease.

Mortality and causes of death

The severity of the course of trichinosis and its outcome largely depend on the organ damage that develops during the 3-4th week of the disease; one of the most serious among them is myocarditis. With its development there are tachycardia, hypotension, cardiac rhythm disturbance, development of heart failure. The borders of the heart are enlarged, diffuse lesions of the myocardium, sometimes coronary disorders, are revealed on the ECG. Myocarditis in trichinosis is one of the main causes of death occurring in the period from 4 to 8 weeks of the disease. Following the myocarditis, the cause of death is the defeat of the lungs. With medium-heavy current, clinically and radiologically, signs of bronchitis and "flying" infiltrates in the lungs are revealed. In severe form, pulmonary lesions can take the form of lobar pneumonia with the appearance of serous effusion in the pleural cavity. Possible edema of the lungs, which is also promoted by the development of cardiovascular failure. It is possible to attach a secondary bacterial infection. The defeat of the central nervous system manifests itself as headache, drowsiness, sometimes delirium, signs of meningism associated with edematous syndrome. In later terms, severe disorders are recorded, such as polyneuritis, acute anterior poliomyelitis, severe myasthenia gravis (myasthenia gravis), meningitis, encephalitis with development of psychosis, local paresis or paralysis, coma. Mortality in the absence of adequate treatment can reach 50%.