Subfebrile temperature 37 2. Subfebrile condition in children: causes and examination. Basic clinical terms

What does subfebrile temperature mean? The Latin prefix sub means "under, about" (think of words like submarine, offal or subtropics). And febris is Latin for fever. So literally subfebrile temperature is defined as "near fever".

The temperature of the human body is a complex indicator of the thermal, that is, the thermal state of the body. The mechanism of our thermoregulation is "automatically" set to a normal value of +36.6°C and allows its physiological changes within plus or minus 0.5-1°C. In this case, the general temperature range is 36-39°C. When the thermometer rises to + 38-39 ° C, doctors talk about febrile temperature, and above + 39 ° C - about pyretic. What is subfebrile temperature?

The classic subfebrile body temperature is + 37-37.5 ° C, but experts indicate a higher figure - 37.5-38 ° C. So it is quite reasonable that subfebrile temperature of 37 degrees and up to + 38 ° C is recognized by most domestic doctors as “near fever”, and their Western colleagues consider it to be 99.5-100.9 ° F or 37.5-38.3 ° C.

Causes of subfebrile temperature

The causes of subfebrile temperature, as well as febrile and pyretic, are associated with changes in the work of the limbic-hypothalamic-reticular system of the body. Simply put, temperature is regulated in the hypothalamus, which acts like a thermostat. Endogenous or exogenous pyrogens cause the release of prostaglandins (inflammatory mediators), and they act on neurons responsible for thermoregulation, which are located in the hypothalamus. And the hypothalamus generates a systemic response, and as a result, the body is given a new temperature level.

Signs of subfebrile temperature

Subfebrile body temperature accompanies a number of diseases, sometimes being, in fact, their only symptom, fixed at the initial stage of development. In addition to fever, this condition may not manifest itself in any other signs, which poses a potential threat to health.

So the key signs of subfebrile temperature are a periodic or permanent (permanent), short-term or long-term increase in temperature to + 37-38 ° C.

Subfebrile temperature as a symptom

Subfebrile temperature is a sign of a particular pathology. Subfebrile temperature and cough, subfebrile temperature and headache, as well as weakness and subfebrile temperature are typical symptoms not only of SARS or influenza, but also of focal pneumonia and pulmonary tuberculosis. In particular, with focal or infiltrative tuberculosis, subfebrile temperature is observed in the evenings, which rises for 3-4 hours to + 37.3-37.5 ° C.

Often, subfebrile temperature after SARS is the result of incomplete recovery, weakened immunity, or the action of drugs.

In most cases, subfebrile temperature with bronchitis will not rise above +37.7 ° C; subfebrile temperature after pneumonia is kept in approximately the same range. Often doctors cannot determine the exact cause of this phenomenon and call it post-infectious subfebrile condition.

The characteristic subfebrile temperature in tonsillitis is 37-37.5 ° C, and the subfebrile temperature after a sore throat can remain at the same level for one to two weeks. A longer subfebrile condition should be alarming, because, as you know, tonsillitis quickly becomes chronic decompensated, and streptococcal infection with frequent tonsillitis has a pathological effect by intoxicating the tissues of the heart, causing infective endocarditis, and affecting the kidneys, leading to glomerulonephritis.

Subfebrile temperature with cystitis, along with other symptoms of this disease, disappears after appropriate drug therapy. However, when subfebrile temperature persists to 37.5-37.8 ° C after the end of treatment, there are good reasons to assume that inflammation from the bladder has gone to the kidneys and threatens with pyelonephritis.

Subfebrile temperature after tooth extraction, as well as subfebrile temperature after an operation performed on any tissues and organs, may have a separate list of reasons, among which in the first place is the body's reaction to a damaging factor and infection (for example, infectious blood poisoning - pyemia). The drugs taken both before and after surgery also contribute.

Subfebrile temperature in oncology is most often observed with myelo- and lymphocytic leukemia, lymphomas, lymphosarcomas and cancerous lesions of the kidneys. As oncologists note, prolonged subfebrile temperature - for six months or even more - is one of the symptoms of the early stages of these diseases. Also, for oncological patients after radiation and chemotherapy, neutropenic subfebrile condition is characteristic, associated with a weakening of the immune system.

Nausea and subfebrile temperature of the gastroenterologist will suggest intestinal dysbacteriosis. But subfebrile temperature at night usually drops to a physiologically normal level or slightly lower, although it can be kept, for example, with latent herpes infection, inflammation of the bile ducts or hepatitis C.

It should be borne in mind that a constant subfebrile temperature, which remains above normal throughout the day and fluctuates during the day by more than one degree, is a symptom of infective endocarditis. Prolonged subfebrile temperature, which manifests itself every 24-48 hours, is a typical manifestation of malarial plasmodium.

The human immunodeficiency virus acts slowly, so subfebrile temperature with HIV, in the absence of other signs in carriers of this infection, is an indicator of a total decrease in defenses. The next stage may be the defeat of the body by any infection with the development of many immune-mediated diseases.

Subfebrile temperature with VVD

Thermoregulation of the body - as the activity of all internal organs, secretory glands and blood vessels - is coordinated by the autonomic nervous system, which ensures the stability of the internal environment and adaptive reactions of the body. Therefore, disturbances in its work can manifest itself as subfebrile temperature with VVD, that is, vegetative-vascular dystonia.

In addition to spontaneous daytime temperature rise to 37-37.3 ° C, there may be such neurocirculatory disorders as changes in blood pressure and pulse rate, decreased muscle tone, and hyperhidrosis (increased sweating).

Depending on the cause of VDS in clinical medicine, vascular dystonias are genetic, infectious-allergic, traumatic and psychogenic.

Until recently, an increase in temperature in such conditions, that is, without an obvious reason, was defined as a subfebrile temperature of unclear etiology. Now it is already known that here there is a violation of the process of thermoregulation due to diencephalic syndrome - a congenital or acquired dysfunction of the hypothalamus (our main "thermostat").

The congenital causes of this pathology include functional somatic disorders such as VVD, and among the acquired ones are circulatory disorders of the brain in the area of ​​the hypothalamus, craniocerebral trauma, encephalitis, intoxication, etc.

Anemia and subfebrile temperature

Anemia and subfebrile temperature are quite closely related to each other at the biochemical level. Iron deficiency anemia leads to impaired production of hemoglobin and a decrease in its content in red blood cells that carry oxygen to the cells. And with a lack of oxygen in all cells of the body and, first of all, the brain, the metabolic process is disrupted. Therefore - in addition to all other signs of iron deficiency in the body - quite often there is a slight increase in body temperature. Children and adolescents during puberty are most prone to iron deficiency anemia. In addition to low-grade fever, they often have colds, appetite and body weight may decrease.

In addition, poor absorption of iron is associated with a lack of vitamin B9 (folic acid) and vitamin B12 (cyanocobalamin), which regulate hemoglobin synthesis in the bone marrow. And this anemia is called pernicious.

Precision anemia and subfebrile temperature - if you do not pay attention to them - can lead to the development of inflammation and atrophy of the mucous membranes of the gastrointestinal tract.

Subfebrile temperature in women

Subfebrile temperature before menstruation in women refers to physiological periodic changes in thermoregulation (within 0.5 degrees) and is associated with an increased intake of estrogen and estradiol and their metabolic products into the blood: hydroxyestrons, etiocholanolone, methoxyestradiol, etc.

Subfebrile temperature during pregnancy (up to +37.5 ° C) can be observed in the early stages, in the first 12 weeks - due to an increase in the level of progesterone produced by the corpus luteum of the ovaries and its effect on the hypothalamus. Temperatures will return to normal later.

However, a slight but constant subfebrile temperature in pregnant women is quite possible when, against the background of a natural decrease in immunity, blurred symptoms of the so-called TORCH infections: toxoplasmosis, hepatitis B, varicella-zoster virus, rubella, cytomegalovirus and herpes simplex virus. Since all these infections can cause congenital abnormalities of the fetus, it is important to be vigilant at subfebrile temperature during the time and take a blood test for TORCH infection.

And, finally, subfebrile temperature in women very often occurs during menopause, and this is again due to changes in their hormonal background.

Subfebrile temperature in a child

Thermoregulation disorders detected in childhood in at least 2% of cases represent a congenital diencephalic syndrome, that is, problems with the hypothalamus, which was discussed above.

Subfebrile temperature in a child often accompanies infections of the upper respiratory tract, nasopharynx and ears. So, subfebrile temperature and cough can be with SARS, chronic tonsillitis, bronchitis, pneumonia. The temperature is given by teething and vaccinations. Subfebrile condition can be provoked by physical activity, strong excitement, overheating when wearing heavy clothes, anemia, etc.

Subfebrile temperature in a teenager is associated with a period of sexual development, but possible pathologies cannot be ignored. In addition to those listed above (see the Causes of subfebrile temperature section), pediatricians pay special attention to childhood and adolescent thermoneurosis, which is caused by diencephalic syndrome, malignant blood diseases, thyroid gland pathologies, and autoimmune diseases. For example, children under 16 years of age may develop Still's disease or systemic juvenile idiopathic arthritis, which is characterized by weakness and low-grade fever.

It can also be a side effect of long-term use of certain drugs, such as atropine, diuretics, anticonvulsants, antipsychotics, and antibacterials. So, subfebrile temperature with antibiotics occurs due to the fact that their use erases the signs of certain diseases, and then only one symptom remains - an increase in the readings of the thermometer.

There are a number of symptoms that go unnoticed for a long time. These include body temperature called subfebrile. It is a symptom of the disease, and sometimes indicates a very dangerous condition.

Normally, this indicator ranges from 35.5 ° to 37.4 °. It is constantly changing, depending on the time of day, place of measurement, general condition and biological rhythm.

Deviations from the norm are primarily affected by impaired functioning of the hypothalamus and thyroid gland. These two organs of the endocrine system are responsible for the decrease and increase in performance.

What does the diagnosis "subfebrile body temperature" mean?

Such a conclusion of the doctor is due to a long-term increase in indicators in the region of 37-37.5 °. This phenomenon may be accompanied by malaise, or the person will feel completely healthy. It should be noted that subfebrile condition is a rather complex problem. The fact is that difficulties in differential diagnosis arise even for the most experienced specialists.

Causes of subfebrile body temperature

After this phenomenon is discovered, it is necessary to find out what provoked it. For example, if a person recently had a disease or was treated for a long time, then the increase can be directly related to these factors.

However, low-grade fever may also indicate a just emerging disease. To identify the cause, they make a temperature curve, analyze the accompanying changes in well-being, and conduct laboratory diagnostics.

Diseases accompanied by an increase in temperature to subfebrile indicators:

Signs of subfebrile temperature of infectious etiology: poor tolerance to increase; daily fluctuations persist; antipyretic effect. Non-infectious etiology is characterized by a mild and even imperceptible course, the absence of daily fluctuations and a reaction to antipyretic drugs.

When low-grade body temperature is considered safe, like febrile

Not always this condition should be regarded as a symptom of any disease. There are several cases where it is considered quite natural and normal.

Neurosis - stress, emotional overstrain can cause a stable increase, for example, at the end of a work shift. There may be general weakness, chronic fatigue, decreased concentration and performance.

These conditions do not at all indicate the presence of pathology. However, it is necessary to correct the rhythm of life, since neurosis can provoke the development of psychosomatic diseases.

Temperature tail - after an infection, the temperature may persist for some time even after complete recovery. If the disease was very severe, then this phenomenon may be present for another 2 months or longer.

Subfebrile condition can indicate both a relapse of the disease, and the transition of the pathology to a chronic form. In this case, it is recommended to take a blood test in dynamics.

Pregnancy - often subfebrile temperature accompanies the entire period of bearing a child. The phenomenon is due to hormonal changes. A slight increase in the absence of other symptoms, as a rule, is not an alarming sign, but it is worth consulting a doctor to rule out violations.

Causes of subfebrile condition in a child

This condition in the baby becomes a cause for concern. It is not surprising, because in many cases the temperature is the only symptom of the disease.

Subfebrile fever in adolescents accompanies such common pathologies as helminthiasis, adenoiditis and other local inflammations, allergy manifestations, etc. In addition, it is a symptom of such dangerous diseases as tuberculosis, asthma, oncological pathologies and blood diseases.

When the temperature fluctuates from 37° to 38° for 21 days, it is necessary to carry out a comprehensive diagnosis, which includes the following measures:

• Blood tests - biochemical with the definition of rheumatic tests, clinical;
• Urinalysis - daily, for sterility, cumulative samples, general;
• Analysis of feces for the presence of worm eggs in dynamics;
• X-ray of the lungs, paranasal sinuses;
• Tuberculin tests;
• Ultrasound of internal organs;
• Electrocardiography.

Based on the results of analyzes and studies, the pediatrician sends the parents with the child to highly specialized specialists.

It is worth noting that an increase can be as normal as a febrile temperature. This is typical for the reaction to the BCG vaccine in children of the first year of life. In children from 8 to 14 years old, this phenomenon may be associated with the so-called phases of active growth and development.

Treatment of subfebrile temperature

Eliminate this phenomenon becomes possible only after finding out its root cause. Before drawing any conclusions, it is necessary to diagnose subfebrile condition. Not every increase can be attributed to the category of pathology, because it has already been noted that fluctuations of 0.5-1 ° can occur in the evening, depending on the psycho-emotional state, physical activity, hormonal emissions.

The conclusion about the presence of such a symptom is made on the basis of the analysis of the temperature curve.

It, as a rule, is built under the supervision of the attending physician or, as a last resort, according to his recommendations:

• The temperature is measured twice a day - in the morning and in the evening;
• A special sheet is filled out according to the relevant rules - they find the temperature grid and the “T” column. Each branch of the grid is 0.2. Morning indicators are marked with a dot along the ordinate axis, marking the date of measurement. Similarly, note the evening indicators. The points are connected to each other;
• The curve obtained in 3 weeks is analyzed by the attending physician.

If a conclusion is made about subfebrile condition, it is necessary to conduct laboratory and profile studies. First, visit the doctor's office.

Dear readers, glad to meet you again! One of the oldest biomarkers of human health is body temperature. A slight increase in body temperature always brings inconvenience and is most often one of the symptoms of a disease. Subfebrile body temperature, what it is and the reasons for its appearance is the topic of today's article. The topic is quite serious, since low-grade fever for a long time is no less dangerous to health than diseases with a high temperature.

To understand what subfebrile temperature is, you need to understand what temperature is normal for a person.

We are all used to and know that the normal temperature of a healthy person is from 36.4 to 36.8ºС. However, the temperature can fluctuate even during the day, remaining in the range from 35.5 to 37.4 ºС. The temperature level is affected and may vary depending on

• from the time of day
• from the floor
• from age
• from an emotional state
• from climatic conditions,
• from physical activity,
• from eating
• and even from the daily cycle of the Sun.

If we talk about the daily cycle, then the minimum value is noted in the morning hours around 5-6 am, the maximum - in the evening. And even if a person works at night and sleeps during the day, the temperature of such people will still follow the same cycle as that of those who are awake during the day.

Human body temperature is controlled by thyroid hormones and the hypothalamus. Nerve cells of the hypothalamus have receptors that directly respond to body temperature by increasing or decreasing the secretion of TSH, which, in turn, regulates the activity of the thyroid gland, whose hormones (T3 and T4) are responsible for the intensity of metabolism. To a lesser extent, the hormone estradiol is involved in the regulation of temperature (it plays the main role in the thermoregulation of bodies in women during the menstrual cycle), an increase in its level leads to a decrease in basal temperature.

Body temperature in women is half a degree higher than in men. In girls, the temperature becomes stable by the age of 13-14, in boys - by 18. In a state of emotional excitement or stress, the temperature can also change in one direction or another.

Subfebrile temperature values ​​​​may be a reflection of the individual characteristics of the body and may increase from stress, physical work, or being in a stuffy room.

It is interesting to know: temperatures below 35º C indicate the consequences of exposure, at 32º C a person falls into a stupor, loses consciousness at a temperature of 29.5º C and dies at a temperature below 26.5 ºС. Although a record of survival under conditions of hypothermia at a temperature of 14.2 ºС is described.

Subfebrile body temperature - what is it?

And now let's define the concept of "subfebrile temperature." According to Wikipedia, the term "subfebrile temperature" means values ​​​​in the range of 37.1 - 38 ºС. An increase in temperature within these figures for 1-2 days has no pathological significance for the human body and depends on many factors that I have already mentioned above.

But subfebrile temperature for more than three days is called subfebrile condition and is considered a signal that some hidden pathological processes are occurring in the human body. The severity of the pathology depends on the duration of subfebrile condition, and it can last from several days and even up to a year.

In most cases, subfebrile condition passes without obvious symptoms or they are simply not noticed, someone has a fever in the morning, and someone in the evening. Nevertheless, the rise is accompanied by a feeling of fatigue, malaise, weakness, sweating - a person feels that he is not healthy, but he is in no hurry to see a doctor. And he continues to lead his normal life. And this is his big mistake. I repeat, the harmlessness of the condition can lead, with untimely treatment, to the development of serious diseases and undesirable complications.

Subfebrile temperature causes

Consider the reasons for which there may be subfebrile condition.

Infectious and inflammatory diseases

An increase in temperature indicates that the body is fighting the toxins that pathogens release, and this is the response of the body. In these cases, fever is accompanied by headache, malaise, weakness. When taking antipyretics, the symptoms quickly disappear.

This group includes acute bacterial and viral infections - SARS, laryngitis, pharyngitis, bronchitis, inflammatory diseases of the gastrointestinal tract, urogenital area, post-injection abscesses.

With HIV infection, there is a gradual destruction of T-lymphocytes, which are responsible for the state of the body's defenses against external and internal pathogenic agents. The temperature reaction is a protective reaction of the body.

Sluggish chronic foci of infection - carious teeth, sluggish ulcers in patients with diabetes mellitus, with tuberculosis, regardless of location, the temperature rises as a protective reaction of the body to the inflammatory process and the response to intoxication of the body.

With viral hepatitis, cholangitis and herpes infection, subfebrile temperature may decrease by night.

Intestinal dysbacteriosis is always accompanied by nausea.

Non-communicable (somatic) diseases

This group of diseases is characterized by an increase in temperature not only throughout the day. In some diseases, an increase is observed only in the morning and can be observed in oncological diseases, anemia, thyrotoxicosis, and vegetative-vascular dystonia.

With thyrotoxicosis, an increase in temperature occurs as a result of a high concentration of thyroid hormones in the blood plasma.

With iron deficiency anemia, there is a violation of the production of hemoglobin and insufficient supply of oxygen to tissues, first of all brain cells suffer, metabolism is disturbed, which is often accompanied by a slight increase in temperature. In addition to this symptom in children and adolescents, there is a decrease in appetite and body weight, children often suffer from colds for a long time and often.

Thermoregulation of the body is closely related to the work of the autonomic nervous system. Spontaneous increase can occur as a result of any traumatic, infectious-allergic, psychogenic factor. In addition, the symptoms of VVD will be accompanied by a change in blood pressure, pulse, a decrease in muscle tone and the appearance of sweating.

Subfebrile temperature can be observed after any operation on the internal organs, including after tooth extraction. This is the response of the body to the inflammatory factor after injury, and as a result, the attachment of a bacterial infection in the wound.

As a result of hemolysis of erythrocytes, in which tissue necrosis occurs, which occurs during strokes, myocardial infarction, with prolonged tissue compression syndrome, etc. a slight increase in temperature may also be observed.

Malignant tumors

With tumors, the body reacts with low-grade fever to the action of endogenous toxins, which are formed as a result of the growth of malignant tissue. Similar is observed in lymphomas, lymphocytic leukemia, lymphosarcomas and kidney cancer.

Prolonged subfebrile temperature, according to oncologists, is a sign of malignant tumors in the early stages. And you should pay very close attention to this.

After undergoing chemotherapy sessions, there is also a slight increase in temperature as a result of a weakened immune system.

Functional disorders of the nervous system

An increase in temperature to subfebrile values ​​occurs in the following cases:

• stress, strong excitement, fear and other psycho-emotional overload,
• a history of traumatic brain injury,
• with autonomic neurosis - a disease associated with an organic change in the autonomic nervous system and a violation of its normal operation,
• violation of metabolism and functions of the endocrine system,
• allergization of the body with constant or temporary contact with various allergens.

Autoimmune diseases

These are diseases in which the immune system does not recognize organ cells, mistaking them for foreign ones and trying to kill them. The concomitant inflammatory process is accompanied by an increase in temperature. Quite a few diseases of this nature are recorded, they differ from each other in symptoms and lesions of various organs.

This class of diseases includes all helminthiases: ascariasis, enterobiasis, diphyllobothriasis, toxaplasmosis, etc. All these diseases, in addition to subfebrile temperature, are accompanied by dyspeptic disorders, loss of appetite, and weight loss.

Subfebrile temperature in women

In women, subfebrile condition is possible for some other reasons. Here is some of them:

1. Before menstruation, a woman's hormonal background changes, as a result of an increase in the level of progesterone, which reacts to this with an increase in temperature.
2. Tides during the climax. And in the postmenopausal period, the production of estrogen and progestogen decreases. The brain does not adequately perceive the normal temperature and at the time of the release of the next portion of estrogen, the woman feels a feeling of heat, which is accompanied by an increase in temperature, after an attack of heat, the temperature drops to normal and during this period the woman feels a feeling of chills.
3. The temperature can sometimes rise during pregnancy, this is observed in the first trimester. If at the same time the woman's well-being does not change, then this should be regarded as a reaction of the body to the development of the fetus. If symptoms appear at a temperature: cough, runny nose, pain, you should definitely tell your gynecologist about this.
4. The enthusiasm of young women for various diets for weight loss leads to stress, increased fatigue, exhaustion of the body, and as a response of the body, some women may experience a low-grade fever.

If such reactions of the body occur rarely and are short-lived, then there is no reason to worry. But if this happens all the time, this is a reason to go to the hospital.

Subfebrile temperature in a child - causes

If, when the child is unwell, the temperature is above 37 ºС, the parents immediately begin to sound the alarm. And not in vain. In children, as in adults, undiagnosed diseases can hide under subfebrile temperature.

Among the reasons, many are common with adults. But there are a number of circumstances that do not depend on the presence of diseases, but should force parents to reconsider care, especially for infants. So, in children under one year, temperature fluctuations are more pronounced due to intensive metabolism. The baby reacts faster to heat, physical activity and anxiety.

An increase in temperature in young children is accompanied by lethargy, whims and prolonged crying, refusal to eat, frequent regurgitation, increased sweating, poor sleep, rapid breathing and heart rate. As soon as the baby is swaddled or calmed, the temperature will return to normal.

At an older age, subfebrile temperature should already alert, since this is one of the symptoms of diseases.

For older children, an aspirin test is performed with an increase in temperature. Its essence is as follows: when the temperature rises, the child is given an antipyretic, only in half the dosage, and after half an hour the temperature is measured again. If the temperature has become normal, this indicates the presence of some kind of infection, most often SARS, if it remains the same, then it is necessary to look for the cause in a somatic disease.

In any case, it should be remembered that it is necessary to treat not the temperature, but to look for its causes. And only a pediatrician with an appropriate examination can find the cause.

Temperature in a teenager

The causes of fever in a teenager are the same as in adults and children.

Among the infectious causes, viral infections and diseases of the ENT organs come to the fore, among the somatic ones, subfebrile temperature is accompanied by inflammatory diseases of the gastrointestinal tract, urinary tract, dental diseases, diseases of the endocrine system. Worm infestations are not excluded.

But most of all, prolonged fever, accompanied by weakness and excessive sweating, should be of concern. It could very well be tuberculosis. Recently, the incidence of this infection is quite often recorded among children and adolescents, so it is necessary to assess the epidemiological environment of the adolescent, as well as the presence and result of the Mantoux reaction and the diaskin test, vaccinations against tuberculosis.

But it is possible to know exactly the cause of the elevated temperature only by passing the appropriate examination.

Examination at subfebrile temperature

In order to correctly diagnose and find out the cause of subfebrile temperature, the doctor must find out the epidemiological history. When collecting it, in addition to complaints, they pay attention to previous diseases, contact with infectious patients, living conditions, hygiene, recent walks and travels: natural focal and especially dangerous diseases can be hidden under subfebrile condition.

But for an accurate diagnosis, the following laboratory tests will be required:

• Complete blood count - the presence as a result of increased ESR, leukocytosis - will indicate the presence of an inflammatory process; low hemoglobin levels will indicate anemia and helminthic infestations; an elevated level of eosinophils indicates allergies and the presence of worms, etc. What does a general blood test and its interpretation, read
• Urinalysis - the presence of elevated ESR, leukocytes and protein as a result indicates inflammation in the urinary tract. How to pass a urine test
• Sputum for Mycobacterium tuberculosis;
• Blood for the Wasserman reaction for the diagnosis of syphilis;
• Blood for the presence of antibodies to hepatitis B and C, as well as for HIV infection;

Adults should contact their primary care physician, adolescents should contact their pediatrician, and children should consult their primary care physician. The local specialist will assess your condition and refer you to the appropriate specialist: infectious disease specialist, endocrinologist, neuropathologist, surgeon, etc.

Dear readers, today you have learned what subfebrile body temperature is and the reasons for its occurrence. I hope that you understand the importance of this issue and now you know how to act in a similar situation.

High temperature indicates the presence of the disease. But it happens that the temperature is elevated, and other symptoms are not observed. In this case, doctors use the concept of "subfebrile temperature." This condition is often seen in children. What are the causes of subfebrile temperature and does the child need treatment? This will be discussed.

Signs of subfebrile condition in children

Subfebrile temperature is a condition in which an elevated temperature lasts for a long time and can reach 38.3 ° C, and there are no obvious signs of the disease.

Against the background of elevated temperature, the following symptoms may be observed:

• weakness;
• lethargy;
• loss of appetite;
• excessive sweating;
• increased heart rate and respiration;
• regurgitation (in infants);
• sleep disorders;
• increased nervousness.

Usually subfebrile temperature is in the range of 37-38.3 ° C and lasts from two weeks or more

Most often, prolonged subfebrile condition occurs in children aged 7–15 years.

Features of the temperature regime in a child

In an adult, the normal body temperature, as you probably know, is 36.6 ° C. In a child, it can be lower or higher, and also change throughout the day. In infants, an increase in temperature is observed during feeding or with various disturbances. Thus, if it reaches 37.5 ° C, this does not always indicate the presence of any disease.

There are a number of factors that affect the physiological changes in body temperature in a child:

• circadian rhythms - the maximum rate is observed in the second half of the day, the minimum - at night;
• age - the younger the child, the more pronounced the temperature fluctuations, which occurs as a result of intensive metabolism;
• environmental conditions - in the hot season, the child's body temperature may also rise;
• physical activity and anxiety - contribute to an increase in this indicator.

Parents should measure the temperature of the child in the morning, afternoon and evening for two weeks and write down the results in a notebook.

In full-term newborns, daily temperature fluctuations are absent and appear closer to the age of one month.

The main causes of subfebrile temperature

Subfebrile temperature may indicate a malfunction in the work of the child's body. Sometimes she talks about the presence of hidden diseases. In order to treat them in a timely manner, it is necessary to find out the cause that led to subfebrile condition.

Infectious diseases

Prolonged fever in children can be caused by the following diseases:

• pulmonary tuberculosis (also accompanied by general weakness, loss of appetite, fatigue, increased sweating, prolonged cough, emaciation);
• focal infections (sinusitis, cholecystitis, tonsillitis, dental problems, and others);
• brucellosis, giardiasis, toxoplasmosis;
• helminthiasis.

Noncommunicable diseases

Among the diseases of a non-infectious nature, which lead to prolonged subfebrile condition, are autoimmune disorders, blood diseases. Sometimes malignant tumors are the cause of a prolonged increase in body temperature. In childhood, oncological diseases are rare, but sometimes they affect the child's body. Also, the causes that cause low-grade fever include rheumatic diseases, iron deficiency anemia, and allergies. Endocrine diseases also contribute to a prolonged increase in body temperature. As you know, all biological processes take place with the release of heat. The mechanism of thermoregulation contributes to the maintenance of normal body temperature. If the work of the adrenal glands is disturbed, a spasm of the superficial vessels of the extremities is observed. This prevents the body from producing excess heat. As a result, the body temperature rises, and the child's feet and hands may remain cold.

With infectious subfebrile condition, physiological daily fluctuations in temperature persist, it is poorly tolerated and goes astray after taking antipyretics. If the cause is a non-communicable disease, daily temperature fluctuations are not observed or changed, antipyretics do not help.

Consequences of viral diseases

After a viral illness (flu or SARS), a “temperature tail” may remain. In this case, subfebrile condition is benign, changes in the analyzes are not observed, and the condition returns to normal within two months.

In the last century, doctors conducted studies in which two educational institutions took the temperature of children from 7 to 15 years old. It was increased in 20% of students. There were no signs of respiratory illness.

Psychogenic disorders

In suspicious, closed, irritable and uncommunicative children, there is a high probability of manifestations of prolonged subfebrile condition. Therefore, it is recommended to treat such a child more carefully. In no case should you shout, ridicule and shame him. It is very easy for vulnerable children to be traumatized. Also, the cause of subfebrile temperature can be mental stress. This can happen while waiting for some important event that delivers the experience.

Examination methods

To determine subfebrile condition in a child, daily temperature monitoring is required. It must be measured every 3-4 hours, including during sleep. The diseases that cause such a reaction are varied. To accurately establish them, it is necessary to conduct a comprehensive examination.

It is important to conduct a comprehensive examination, since a timely unrecognized subfebrile condition can pose a serious threat to the child.

General examination and analyzes

First, the doctor should conduct a general examination of the child to assess his condition. It is necessary to examine the lymph nodes, abdomen, listen to the noise in the heart and lungs. You also need to examine the skin, mucous membranes, joints, mammary glands, ENT organs.

Laboratory examination methods include:

• general analysis of urine and blood;
• sputum examination;
• biochemical, serological blood test;
• study of spinal cord fluid.

Carrying out complex clinical and laboratory diagnostics is prescribed in order to exclude a latent disease.

Instrumental examination methods

For children with elevated body temperature, which persists for a long time, the following procedures are prescribed:

• radiography;
• echocardiography;
• computed tomography.

An x-ray examination is performed if there is a suspicion of the presence of diseases of the ENT organs or the respiratory tract. In such cases, an x-ray of the lungs and paranasal sinuses is prescribed. The causes of prolonged subfebrile condition may be autoimmune diseases. Therefore, it is necessary to conduct rheumatological tests.

Aspirin test

In older children, an aspirin test is performed to identify the cause of subfebrile condition. It is prescribed to diagnose a possible inflammatory process, as well as a neurological disease. Its essence is to register the temperature after taking aspirin according to the established scheme. First, the child should take half a tablet, and after half an hour, his temperature is measured. If it has decreased, an inflammatory process occurs in the body. When the temperature remains unchanged, this means that the cause is a non-infectious disorder.

Consultations of specialists and examinations of parents

In the presence of subfebrile temperature, it is recommended to consult with the following specialists:

• gynecologist (girls undergo pelvic examinations);
• hematologist (to exclude oncological diseases of the lymphatic tissue and the hematopoietic system);
• neurologist (to rule out meningitis);
• oncologist (a search for focal pathology is performed);
• rheumatologist (detection of articular syndromes);
• infectious disease specialist (to exclude an infectious process);
• phthisiatrician (examination for tuberculosis).

In addition, it is necessary to examine the parents of the child, as well as other family members. This is necessary to detect possible foci of latent infection that supports subfebrile condition.

Parents should take full responsibility for the examination of the child. It is necessary to conduct a comprehensive diagnosis so that the doctor can prescribe an effective treatment.

Is treatment required?

The first question that parents of a child with subfebrile temperature ask is the need for treatment. Is therapy required for prolonged subfebrile condition? There can be only one answer in this case: treatment is necessary.. As you know, constantly elevated temperature does not have the best effect on the work of the child's body, undermining its defenses.

Treatment of subfebrile condition in a child consists in eliminating the cause that led to this condition. If the temperature rise is provoked by non-communicable diseases, drugs are used, the action of which is aimed at getting rid of these diseases. When eliminating functional disorders of the central nervous system that caused a violation of heat transfer, hypnotherapy, acupuncture is used. Glutamic acid can also be used.

If the presence of infectious diseases is detected, all actions are aimed at eliminating the infection. In the presence of inflammation, complex treatment with anti-inflammatory drugs is mandatory. If the cause of subfebrile condition in a child is a viral disease, therapy is not required, since the condition returns to normal on its own after a while.

The task of parents is to create the right regimen for the child. There is no need to cancel school attendance. Just need to warn teachers that a child with a fever can get tired faster. It is desirable for children with subfebrile condition to spend a lot of time in the fresh air, to sit less near the TV. It is useful to carry out hardening procedures.

Parents need to remember that it is not the temperature that needs to be treated, but its cause. To identify a violation, it is necessary to show the child to the doctor. The prognosis of subfebrile condition in children is good. Proper treatment, as well as the daily routine, quickly normalizes the temperature. Few have subfebrile condition remains in adulthood.

Symptoms: prolonged fever, temperature 37, progressive increase in body temperature, palpitations, clouding, loss of consciousness, nausea, weakness, convulsions, heaviness in the head, headache, feeling hot, feeling cold, chills, excruciating thirst, increased nervous excitability, irritability, neurosis, hallucinations, pale skin, redness of the skin, insomnia, shortness of breath, excessive sweating, chest pain, abdominal pain.

Subfebrile temperature is an elevated body temperature that lasts for a long period of time. In diseases of the autonomic nervous system, this temperature can last for months and years, and the amplitude of its fluctuations usually does not exceed 37 - 37.8 degrees.

In our practice, this symptom is very common. It is associated with dysfunction of thermoregulation, one of the main functions of the autonomic nervous system. Actually, it is thanks to this function of this part of the nervous system that we have the opportunity to observe on the thermogram (thermal imaging study) disturbances in one or another vegetative node.

Subfebrile temperature may be accompanied by general malaise, undulating manifestations of excessive sweating, feeling hot or cold, chills and other symptoms that usually accompany elevated body temperature or a general disorder of the autonomic nervous system (headache, heart palpitations, etc.).

Case Studies

Woman, 21 years old, student.

In December 2013, a young girl came to the clinic. For the last few months, the body temperature has been constantly kept at 37.2-37.5. The physique is asthenic, the skin is pale, while increased sweating, from time to time threw into the heat. At times, increased irritability and anxiety joined the symptoms. I had a headache several times a week. Often experienced general weakness, melancholy, dizziness.

First, the patient went to the therapist, who prescribed a number of examinations: general and biochemical analysis of urine and blood, X-ray of the lungs, ultrasound of internal organs, etc. The reasons for the elevated temperature could not be identified. The doctor said that this is primary hyperthermia against the background of vegetative dystonia, that this is normal and will pass with age. You need to gain some weight, walk more in the fresh air, relax, do physical exercises, you can drink vitamins.

In such a state, studying and working became more and more problematic: “it was difficult to think”, I constantly wanted to drink and, as a result, go to the toilet, it was often necessary to leave the room and go out into the fresh air. The girl's parents were looking for options to alleviate such a diagnosis and came to our clinic.

Vegetative disorder arose against the background of a stressful lifestyle and mild traumatic brain injury at the age of 14 years.

After two courses of treatment, the girl fully recovered.

Woman, 25 years old.

A young girl contacted us in 2015. Since February 2014, she began to experience panic attacks (vegetative crises).

About a year before the first bout of inexplicable fear, the girl underwent surgery under general anesthesia. Immediately after that, symptoms such as sleep disturbance and increased anxiety began to appear. In addition, with a strong psycho-emotional load (“worried”), the girl’s temperature increased to 37.5 degrees and could last for several hours.

The general condition of the patient was characterized by constant anxiety and chills. The extremities were usually cold. Worried about heaviness in the neck.

She underwent one course of treatment at the Clinical Center for Autonomic Neurology. Already during treatment, panic attacks ceased to bother. Soon the patient noticed a steady improvement in her condition. A month after the course, she felt completely healthy.

Other symptoms of VVD

Myths and truth about VVD

Alexander Ivanovich BELENKO

Head and leading specialist of the Clinical Center for Autonomic Neurology, doctor of the highest category, candidate of medical sciences, clinician with extensive experience in the field of laser therapy, author of scientific papers on functional methods for studying the autonomic nervous system.

- Put yourself in the place of a doctor. The patient's tests are fine. All kinds of examinations from ultrasound to MRI show the norm. And the patient comes to you every week and complains that he feels bad, has nothing to breathe, his heart is pounding, sweat is pouring down, that he constantly calls an ambulance, etc. You cannot call such a person healthy, but he does not have a specific disease. This is - VVD - a diagnosis for all occasions, as I call it ...

VSD in faces

This page publishes excerpts from patient histories on the main complaints with which people turn to us for help. This is done with the aim of showing how different and “complex” the symptoms of vegetative-vascular dystonia can be. And how closely sometimes it is “soldered” with violations in the work of organs and systems. How it "masquerades" as "cardiac", "lung", "stomach", "gynecological" and even "psychiatric" problems that people have to live with for years...