Polyneuropathy in pregnancy is a multiple lesion of mainly distal parts of peripheral nerve trunks that occurs in connection with pregnancy and completely regresses after its resolution. In the clinical picture, there are sluggish distal paresis, muscle hypotension, hyporeflexia, a decrease in complex types of sensitivity, with relative preservation of superficial ones. The diagnosis of “polyneuropathy in pregnancy” is established according to neurological examination and additional examinations after excluding other causes of polyneuropathy. The treatment is carried out by obstetricians and gynecologists together with neurologists. It is based on the appointment of B vitamins, detoxification, infusion and desensitizing therapy.
General information
The symptoms of polyneuropathy associated with pregnancy were first described in 1888. Since they were diagnosed in women in labor, the authors classified them as postpartum neuritis. Later it turned out that similar symptoms observed after childbirth, as a rule, occur during pregnancy. In this regard, the disease was called “polyneuropathy in pregnancy”. Polyneuropathy is understood as multiple lesions of peripheral nerves. Along with post-infectious, diabetic, paraneoplastic, alcoholic polyneuropathy, polyneuropathy in pregnancy is one of the forms of this pathology.
Currently, polyneuropathy in pregnancy is the subject of joint supervision of specialists in the field of neurology, obstetrics and gynecology. It refers to complications of pregnancy, can significantly affect the condition and well-being of a pregnant woman, but at the same time does not pose any danger to the development of the fetus.
Etiology and pathogenesis
It is possible that the polyneuropathy in pregnancy has a polyethological basis. In its occurrence, the leading role is assigned to the toxicosis of pregnant women and the development of neuroallergia. It is impossible to deny the appearance of some endogenous intoxication of the pregnant woman’s body with fetal waste products. The degree of this intoxication, apparently, depends on the premorbid background of the pregnant woman herself – the existing metabolic disorders, abnormalities in the work of the organs responsible for the neutralization and elimination of toxins (the presence of liver dysfunction, hepatitis, glomerulonephritis, chronic pyelonephritis, renal failure). On the other hand, there is an immunological theory according to which polyneuropathy in pregnancy occurs as a result of hypersensitivity of the pregnant woman’s body to foreign fetal proteins.
Thus, both toxins, the content of which increases during pregnancy, and antibodies produced to fetal protein structures foreign to the pregnant woman’s body can have a toxic effect on peripheral nerves. Studies have shown that motor nerve fibers are less resistant to such pathological effects. Therefore, polyneuropathy in pregnancy is manifested primarily by disorders of the motor sphere. Moreover, the susceptibility of nerve fibers to toxins increases in conditions of their insufficient trophic support, for example, with hypovitaminosis with deficiency of B vitamins.
Distal parts of peripheral nerve trunks located in the thickness of muscle tissues are mainly affected. The defeat of sensory fibers is selective in nature — at first more complex types of sensitivity are affected (vibrational sensitivity, a sense of discrimination, a sense of localization), surface perception (temperature and pain sensitivity) is disturbed much later and suffers less pronounced. Toxins circulating in the blood of a pregnant woman have an irritating effect on parasympathetic fibers. The defeat of peripheral parasympathetic fibers leads to disorders of the trophic tissues, which is manifested by slow healing of wounds (including birth injuries), the rapid occurrence of bedsores, if necessary, to observe bed rest. Irritation of the vagus nerve causes bradycardia, arterial hypotension, a tendency to vomiting, increased secretion of gastric juice, increased intestinal peristalsis, etc.
Symptoms
Polyneuropathy in pregnancy has an acute or subacute course. A general violation of well-being is characteristic, against which there are pains and unpleasant sensations (paresthesia) in the hands and feet, forearms and shins. At the beginning of the disease, such muscle weakness can be interpreted as a general weakness that often occurs in pregnant women with toxicosis. The presence of pain syndrome with its weak intensity is attributed to hypersensitivity and nervousness of the pregnant woman. However, the increasing paresis in the distal extremities refute the initial assumptions and force the woman to consult a doctor.
The clinical course of polyneuropathy in pregnant women is aggravated by the occurrence of repeated vomiting, which results in dehydration of the body. Tachycardia occurs up to 130 beats / min, weakness increases. Patients note thirst, dry mouth. This condition requires urgent hospitalization of a pregnant woman to stop vomiting and replenish fluid losses by infusion.
Diagnostics
Polyneuropathy in pregnancy is diagnosed by a neurologist when the presence of sluggish peripheral paresis of the distal type is detected in the neurological status, accompanied by a decrease in tendon reflexes and muscle hypotension, a violation of complex types of sensitivity. The study of the latter is carried out by applying tactile irritations in various parts of the body (assessment of the sense of localization), simultaneous application of 2 irritations (assessment of the sense of discrimination), “tracing” various numbers and geometric shapes on the patient’s skin (assessment of two-dimensional spatial sense), asking to name an object after feeling it (assessment of stereognosis). The analysis of surface types of sensitivity is carried out by applying small painful irritations with a special needle. As a rule, with this type of polyneuropathy, it does not determine significant disorders.
The diagnosis is valid if polyneuropathy is not a manifestation of any other disease, for example, Guillain-Barre syndrome, polio, acute intermittent porphyria. During the diagnosis, it is necessary to exclude other numerous etiofactors of the occurrence of polyneuropathy in a pregnant woman — diabetes mellitus, infections, exogenous intoxication, metabolic disorders. For this purpose, general clinical tests, biochemical blood test, blood sugar determination, kidney examination (Zimnitsky test, kidney ultrasound) and liver (biochemical liver tests, liver ultrasound) are carried out. Neurophysiological testing using electroneurography and EMG allows to assess the condition and function of peripheral nerves.
Treatment
Polyneuropathy in pregnancy requires mainly symptomatic treatment. Therapy with vitamin preparations of group B. Intramuscular administration of thiamine (vit. B1), pyridoxine (vit. B6), cyanocobalamin (vit. B12) or oral administration of combined pharmaceuticals with vitamins g. B. Desensitizing and detoxification therapy are carried out in parallel. Intravenous infusions of 5% glucose solution, 0.9% sodium chloride are produced. With a pronounced gag reflex, antiemetics (metoclopramide) are prescribed, 10 ml of 10% calcium chloride is injected intravenously. Pregnant women with polyneuropathy need constant supervision by a neurologist and an obstetrician-gynecologist, adequate management of pregnancy in accordance with the diagnosis.
Prognosis and prevention
Usually, polyneuropathy in pregnancy is resolved after a successful delivery. All pathological changes of the peripheral nervous system undergo reverse development with 100% restoration of neurological functions.
The best prevention is to strengthen the health of girls and women of childbearing age, to exclude the effects on their body of harmful habits (smoking, alcoholism, drug addiction) and exogenous intoxications, moral and physical education of girls, preparing them for future motherhood.