High fever in an adult with and without symptoms

Our body can adapt to the influence of various unfavorable factors, including compensatory mechanisms, one of which is an increase in body temperature to febrile (from 38 to 39℃) and hectic (above 39℃) values. This process is controlled by the thermoregulation center in the hypothalamus, a small area of the diencephalon.

Most people, and not without reason, consider high temperature a dangerous symptom. And the reaction to this symptom is unambiguous - bring it down. However, before finding out why high temperature is dangerous in an adult, you need to find out what values are considered high, because everyone has their own opinion on this matter.

Hectic body temperature is considered safe for a healthy adult and has a positive effect as long as it does not exceed 40℃. Temperature readings in the range from 39℃ to 41℃ are also called pyretic. At such values, the fight against infectious agents is most intense, however, it is not easy for the body to withstand such pressure for a long time. The benefit of high temperature is that when it rises, the rate of metabolism, blood circulation and production of endogenous interferon increases. Under such conditions, the body intensively suppresses foreign microorganisms and repairs damage. However, a significant increase in body temperature should not be long-term.

For adults, constant or rising temperature readings over 39℃ without an episodic decrease, recorded over 72 hours or more, are considered dangerous. If the thermometer shows a value from 40 to 41℃, then such a situation is dangerous regardless of its duration.

The danger of hyperthermia is also associated with the acceleration of metabolism and the increased need of all organs for oxygen, since they operate in overload mode, and their energy reserves are quickly depleted. First of all, the heart muscle is overloaded by hyperthermia, it pumps much larger volumes of blood to provide the organs with the oxygen they need. This is expressed in an increase in pulse rate and respiratory cycles (inhalation-exhalation). However, the heart's need for oxygen is very high and even intense breathing cannot satisfy it. The brain and, accordingly, the central nervous system also suffer, which is expressed by convulsions, loss of consciousness. The water-salt balance is disturbed, which is also fraught with complications. Temperature readings above 41 ℃ are called hyperpyretic, an increase to such values is very dangerous, so it is undesirable to allow it at all, even for a short time.

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Causes of high temperature in adults

The body temperature increases to febrile and higher values due to many reasons. This is a common symptom, probably inherent in most diseases. High body temperature (we will consider values above 38℃ in this context), unlike subfebrile, is never a normal variant, and its increase indicates that the body is forced to turn on defense mechanisms against something - be it an infection or heat stroke. Moreover, in two different people, the same reason can cause an increase in temperature to varying degrees, as well as in the same person at different periods of his life.

The most common cause of high temperature in adults is infection of the respiratory organs with pathogens transmitted by airborne droplets and causing their acute diseases. Temperatures exceeding 38℃ manifest, in most cases, viral and bacterial infections of the respiratory organs: flu, tonsillitis, bronchitis, pneumonia, infectious mononucleosis, combined lesions.

Infections transmitted by the oral-fecal route, with contaminated water and food - viral hepatitis A, yersiniosis, brucellosis, poliomyelitis, leptospirosis and many others also often begin with a sudden rise in temperature to pyretic values. High mercury readings are observed in inflammation of the membranes of the brain and spinal cord (meningitis, encephalitis, meningoencephalitis) of various origins, Charcot's disease, malaria, typhoid, and sometimes tuberculosis.

Acute nephritis, diseases of the genitourinary organs, pancreatitis, appendicitis, cholecystitis are often accompanied by high fever.

Post-traumatic and post-operative purulent complications (abscess, phlegmon, sepsis); alcohol and drug intoxication; acute allergic or post-vaccination reaction; damage to the endocardium, myocardium, pericardium as a complication of infectious diseases can occur with an increase in temperature to febrile values.

Risk factors for sudden temperature increase are collagenoses (systemic lupus erythematosus, rheumatoid arthritis, thyrotoxicosis, etc.); vegetative-vascular dystonia; hypothalamic syndrome; malignant diseases of the hematopoietic organs; mental disorders; chronic infections; myocardial infarction and stroke. The terminal stage of cancer of any localization is almost always accompanied by high temperature, and prolonged subfebrile condition can be one of the signs, sometimes the only one, of a developing tumor.

A sudden jump in temperature, even to febrile levels, can occur as a result of overheating (heat stroke), excessive physical exertion, or a combination of the two; frostbite; severe stress.

Pathogenesis

The mechanism for increasing body temperature is triggered when the balance between the production of thermal energy and its release is disturbed, when the rate of heat production exceeds the rate of heat release into the environment.

Hyperthermia develops in completely healthy people at an air temperature of over 37°C and its humidity approaching absolute (100%). In such conditions, heat transfer in the form of sweating and its evaporation becomes impossible, and with a long stay in such conditions, plus also showing physical activity, the body is subject to the so-called "heat stroke".

Hyperthermia as a protective reaction to pathogenic microbes or cellular changes in the body has developed in mammals during the course of evolution. Exogenous pyrogens, the role of which is played by pathogenic microorganisms, stimulate the thermoregulation center to increase body temperature. In response to the appearance of "strangers", the body produces proinflammatory mediators: interleukins 1 and 6, tumor necrosis factor, α-interferon and others, which act as endogenous pyrogens and, by affecting the cells of the anterior hypothalamus, set the "set point" of thermoregulation above the norm. The balance is disturbed and the thermoregulation center begins to "work" to achieve a new balance at a higher reference temperature of the "set point".

The mechanisms regulating the body's heat exchange constantly interact with the effectors regulating other homeostatic functions. Such interaction occurs primarily in the anterior hypothalamus, the cells of which respond not only to heat exchange, but are sensitive to changes in pressure in physiological fluids and the arterial bed, the concentration of hydrogen ions, sodium, calcium, carbon dioxide and glucose. Neurons of the preoptic area of the hypothalamus respond by changing their bioelectric activity and are in constant interaction with other centers coordinating physiological processes.

Symptoms of diseases accompanied by high temperature

The so-called "heat stroke" is not a disease in the generally accepted sense of the word. However, in this case, the dynamic balance of physiological processes in the body is disrupted and the person's condition worsens to the point of collapse. The body temperature rises to febrile values. The skin turns red due to the expansion of peripheral vessels, sweating stops, symptoms of dysfunction of the central nervous system appear (dizziness, nausea, loss of coordination, delirium, convulsions, headache, loss of consciousness). Mild heat stroke occurs as heat fainting - consciousness is switched off as a result of sudden hypotension, which occurs due to the expansion of the lumen of the peripheral vessels of the skin.

Symptoms of high temperature in adults are always quite pronounced. If subfebrile temperature can be detected accidentally, then the increase in temperature to febrile values is itself accompanied by characteristic symptoms. The first signs of malaise are chills, weakness, dizziness, sometimes headache, muscle or joint pain, rapid heartbeat. In most cases, so-called "red" hyperthermia develops. The patient's blood vessels dilate, the skin turns red.

A more dangerous condition is considered to be "white" hyperthermia, which indicates that the vessels have not expanded, but have narrowed. The symptoms of this condition are as follows: pale or marbled-blue skin; cold hands and feet; strong heartbeat; shortness of breath; the patient is excited, may be delirious, convulsions may begin.

But there may not be other symptoms indicating what disease, developing, caused the increase in temperature, at least at first. Sometimes they appear on the second or third day, for example, flu or tonsillitis begin with hyperthermia, and signs of damage to the respiratory organs appear later.

In addition to these, a fairly long series of diseases can cause hyperthermia without additional symptoms that suggest the cause of such a condition. High temperature without symptoms in an adult is an incorrect definition. Asymptomatic course suggests the absence of any signs of malaise, a normal state of health. With high temperature this does not happen, even subfebrile values are usually felt by adults. After all, something makes us put a thermometer and measure the temperature.

Many infectious diseases can begin with a rise in temperature: meningitis, encephalitis, leptospirosis, infectious mononucleosis, typhoid, septic endocarditis, osteomyelitis, atypical pneumonia, measles, mumps. Even chickenpox or rubella, which are often very easily tolerated in childhood and without a rise in temperature, often cause hyperthermia in adults, and specific symptoms appear later and atypically. Temperature fluctuations during the day are typical for tuberculosis or an abscess of internal organs. Malaria can be brought back from tours to hot countries, which also manifests itself with a high temperature. Specific symptoms of the listed diseases appear later, after a day or two.

Inflammation of the meninges (meningitis) is caused by various infectious agents, begins with a sharp rise in temperature, accompanied by the corresponding symptoms. In addition to a severe headache, which can be attributed to high temperature, the patient is very weak, constantly sleeps, sometimes loses consciousness. Characteristic intolerance to bright light, loud sounds, stiffness of the occipital muscles (cannot touch the chest with the chin, turning the head is accompanied by pain). The patient has no appetite, which is natural with high temperature, there may be nausea and vomiting, convulsions. In addition, the patient can be found rashes, in principle, of any localization (typical - feet, palms, buttocks) and resembling small subcutaneous hemorrhages. Meningitis is not very common. For its development, the presence of immune deficiency and / or defects of the nervous system is necessary. However, this disease is very dangerous and does not go away on its own, so a high temperature accompanied by an unbearable headache (the main diagnostic markers) should be a reason to seek emergency help.

Encephalitis is a group of etiologically diverse inflammations of the brain. It may begin with a high temperature and corresponding symptoms, and depending on which part of the brain is affected, more specific symptoms from the nervous system appear. Sometimes the meningeal membranes are involved in the inflammatory process (meningoencephalitis) and symptoms of meningitis are additionally added.

Leptospirosis (infectious jaundice, water fever) – acute fever begins suddenly, the temperature rises to 39-40℃, with a headache that interferes with sleep. The diagnostic marker is severe pain in the calf muscles, sometimes the thigh muscles and skin are involved. In severe cases, the patient cannot stand up. Infection is most often in the summer when swimming in stagnant water contaminated with the excrement of sick animals, in the presence of any wounds on the skin (abrasions, scratches, cuts). The pathogen does not penetrate through intact skin. The incubation period ranges from four days to two weeks. The disease can pass on its own, but severe forms accompanied by jaundice can be fatal.

Endocarditis (infectious, septic) is not uncommon and develops as a complication of acute (tonsillitis, flu) and chronic (tonsillitis, stomatitis) diseases. It can be caused by more than a hundred microorganisms. It manifests itself with a high temperature (over 39℃), later accompanied by shortness of breath, cardiac cough, chest pain and other symptoms.

In addition to various infectious diseases, a feverish state may accompany exacerbations of rheumatoid arthritis, systemic lupus erythematosus, thyrotoxicosis and other connective tissue diseases.

High temperature without a reason does not happen in adults, it is just that this reason is not always obvious. Sometimes the temperature lasts for a long time and the reasons for this condition are not determined. It is believed that idiopathic hyperthermia can be caused by dysfunction of the hypothalamus. This condition is called hypothalamic syndrome, it is diagnosed by excluding other causes.

In addition, high and elevated temperature that cannot be brought down may be the only symptom of oncopathology. Often these are lesions of the blood and lymphatic tissue (acute leukemia, lymphoma, lymphogranulomatosis), but there may be tumors of other localizations. Subfebrile temperature, sometimes jumping, is characteristic of the onset of neoplasm development, and high mercury column readings often indicate tumor decay, metastatic lesions of many organs and the terminal stage of the disease.

High temperature, diarrhea, abdominal pain in an adult are not specific symptoms and require a visit to the doctor for a thorough diagnosis. The presence of diarrhea in most cases indicates intestinal infections (food poisoning). The occurrence of such symptoms is usually associated with the oral ingestion of pathogenic microorganisms - bacteria, viruses, parasites, causing inflammation of its mucous membrane in some area - the stomach, duodenum, small or large intestine. Additional signs indicating an intestinal infection are weakness, headache, rumbling in the area below the navel, bloating. Vomiting is usually observed with intestinal infections, which brings temporary relief to the patient. Its appearance usually precedes diarrhea or these symptoms appear simultaneously.

It is the presence of diarrhea that suggests intestinal infection. There are about thirty common intestinal infections, many of which are manifested by pronounced symptoms with signs of general intoxication - loss of strength, headache, fever with high temperature (39-40℃), as well as abdominal pain and diarrhea combined with nausea and vomiting.

The presence of the above symptoms cannot be ruled out in acute appendicitis, diverticulitis, pancreatitis, hepatitis, inflammation of other digestive organs and the genitourinary system. Although diarrhea in this case is not a typical symptom. High temperature, nausea, vomiting and abdominal pain are more typical for inflammatory diseases. Moreover, the leading symptom is pain, and nausea and vomiting, especially in the initial stages of the disease, appear due to severe pain syndrome.

Cough and high temperature in an adult can be symptoms of an acute respiratory viral infection, with the flu usually beginning with sudden hyperthermia, and the patient begins to cough and sneeze a little later. Infection with other viruses first manifests itself with respiratory symptoms with a gradual increase in temperature.

Acute inflammation of the upper and lower respiratory tract – tracheitis, laryngitis, bronchitis, pneumonia usually manifests itself with intense cough and a rise in temperature, often to febrile levels.

High temperature and cough can be observed with infectious diseases such as measles and whooping cough. Measles is characterized by specific rashes and photophobia, whooping cough is characterized by attacks of choking cough, wheezing and mucus discharge after the attack (sometimes even vomiting).

Hyperthermia and cough are observed in the symptom complex of endocarditis, some gastrointestinal pathologies - viral, parasitic, bacterial invasions, peptic ulcer disease and gastritis.

High temperature and vomiting in adults are observed as a result of food poisoning, intestinal infection, and exacerbation of gastritis or cholecystitis. A significant increase in body temperature, vomiting, sweating and trembling of the limbs can be manifestations of extreme weakness as a result of intoxication or severe pain, for example, with a ruptured ovary or fallopian tube during an ectopic pregnancy. The same manifestations can be hysterical in nature, appear as a consequence of severe stress or overwork.

The sudden appearance of such symptoms may be a sign of acute pancreatitis, small intestinal obstruction, acute appendicitis and hepatitis, central nervous system damage. Hyperthermia and vomiting of bile are also observed with peritonitis.

A rash and high temperature in an adult can be symptoms of childhood infections - measles, rubella, chickenpox, scarlet fever, and an adult infection - syphilis. Meningitis occurs with hyperthermia and rashes. If a patient with infectious mononucleosis has taken a drug belonging to semi-synthetic penicillins (ampicillin, ampiox, amoxil), he will have red spots all over the body. A rash in combination with hyperthermia is observed in typhus, herpes, systemic lupus erythematosus, allergic reactions, and toxic infections. There is a large group of diseases whose symptom complex includes a rash and hyperthermia, so with such manifestations, a specialist consultation is necessary.

A high temperature and a sore throat, a runny nose in an adult, first of all, makes one assume a virus infection, a banal acute respiratory viral infection. There are a great many viruses ready to attack our respiratory system. They are mainly transmitted by airborne droplets - sneezed and coughed in a store, on a bus, a cold employee came to work... And then the next day or three or four days later a runny nose started flowing, a sore throat started, and by evening the temperature rose.

Most often we encounter rhinoviruses, this is the disease characterized by pronounced cold symptoms - runny nose, catarrhal phenomena in the throat, cough. High temperature with rhinovirus infection is rare, usually the body quickly copes with the unstable pathogen and intoxication is not significant. However, hyperthermia cannot be completely ruled out, much depends on the state of the immune system and the nervous system, the presence of chronic diseases.

Adenoviruses are more resistant to the external environment. They are transmitted not only through the air when coughing and sneezing, but also through objects and food, and cause about a tenth of all acute respiratory viral infections. They manifest as a runny nose and sore throat, hyperthermia, affect the mucous membrane of the eye and cause inflammation of the conjunctiva, which is characteristic of adenovirus infection. Sometimes lymphoid tissue is involved in the process - the tonsils and cervical lymph nodes enlarge. Adenovirus infection is fraught with complications - tonsillitis, otitis, sinusitis, myocarditis.

Paramyxoviruses (measles, mumps, rubella, respiratory syncytial infection, parainfluenza and others) - infection occurs through the respiratory system, the disease begins with respiratory symptoms and a rise in temperature, some infections (childhood diseases) have additional specific signs. They are dangerous not so much in themselves, but rather their ability to cause complications.

"Intestinal flu" or reovirus infection also begins with a runny nose and sore throat, cough, then symptoms of gastrointestinal tract damage join - vomiting and diarrhea. High temperature is not typical, more often subfebrile, but it cannot be ruled out. Adults by the age of 25 usually already have immunity to reoviruses, but there are no rules without exceptions.

The onset of the disease is headache, bone aches, chills and high temperature in adults, with time a runny nose and sore throat join in, giving reason to suspect infection with the flu virus. The acute period lasts about five days. The disease is contagious and if bed rest is not observed, it is fraught with complications.

However, many of the diseases described above begin with a sharp and strong jump in temperature: meningitis, infectious mononucleosis, leptospirosis, typhoid and malaria (they can be brought back from a tour to hot countries).

Viral hepatitis A often manifests itself this way, and specific symptoms that allow one to recognize the disease appear later, in two or three days. Therefore, a high temperature in an adult signals the need to visit a doctor or call him to the house (depending on the patient's condition).

Hyperthermia is especially dangerous in a cerebral catastrophe. Hypothermia is considered a more favorable prognostic sign. Such patients usually do not have significant neurological deficits, recover and rehabilitate faster.

High temperature during a stroke in an adult leads to rapid spread of the ischemic damage zone and indicates serious complications: the development of extensive cerebral edema, relapses of latent chronic infections, damage to the hypothalamus, the development of pneumonia or a reaction to drug treatment.

In any case, when an adult's temperature rises to febrile levels and lasts for several days, it is necessary to consult a doctor and determine the cause of this condition.

Diagnostics

High temperature is just one of the symptoms of the disease. To determine its cause, it is necessary to contact a specialist who, based on the examination and questioning of the patient, as well as the necessary laboratory and instrumental studies, will be able to establish a diagnosis and prescribe adequate treatment.

Almost always, patients are prescribed clinical blood and urine tests. They may be enough to diagnose many diseases. For example, in infectious mononucleosis, specific bodies appear in the blood - mononuclear cells, which a healthy person should not have.

If thyrotoxicosis is suspected, a blood test is done for thyroid hormones; to exclude syphilis in the case of rashes in an adult, a Wasserman reaction test is done.

In case of tonsillitis and scarlet fever, a bacteriological examination of a smear from the tonsils is performed; the only way to exclude (confirm) meningitis or encephalitis is a puncture of the cerebrospinal fluid, which allows not only to establish a diagnosis, but also to identify the pathogen.

At the onset of the disease (before the start of intensive antibiotic therapy), leptospirosis is determined using a microscopic examination of blood in a dark field; a week after the onset of the disease, urine microscopy is performed.

Suspicion of lymphogranulomatosis is confirmed by a biopsy of the lymph node with a microscopic examination of the lymphoid tissue.

The tests prescribed depend on the symptoms of the disease that indicate its origin.

Also, to establish the correct diagnosis, the necessary instrumental diagnostics are prescribed depending on the suspected disease - X-ray, ultrasound, computed tomography or magnetic resonance imaging, fibrogastroduodenoscopy, and others.

Based on the results of the examinations, differential diagnostics are made, the type of pathogen in infectious diseases is determined and appropriate treatment is prescribed.

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Is it necessary to bring down a high temperature in an adult?

The actions of the patient and his relatives depend on many factors. First of all, you need to be guided by the person's condition with temperature and its values, as well as the duration of hyperthermia. The patient should be in a cool (≈20℃), but not cold, periodically ventilated room. It is good to turn on the humidifier. The patient should be dressed in light underwear made of natural fabric and covered so as to ensure heat transfer. The underwear should be dry, if there is heavy sweating - change clothes and change the bed. If the patient is shivering, cover him warmer, warm and rub the limbs, when there is no chill, you can even cover him with a light sheet (the patient should be comfortable - not hot, but not cold).

Many people are interested in the question of whether it is necessary to bring down a high temperature in an adult. If a person does not have and has never had convulsions with a high temperature and the condition is satisfactory, then in the first day it can not be brought down even at readings from 39 to 40 ℃. It is imperative to monitor the patient's condition, providing him with rest and plenty of warm drinks, the temperature of which is approximately equal to the patient's body temperature. The next day, a doctor must be called to the patient.

Consequences and complications

Prolonged hyperthermia without periodic temperature reduction can have negative consequences for the body, although the increase in temperature is in most cases a compensatory process. At a temperature above 38℃, most pathogenic microorganisms and even modified tissue cells in the tumor process die. However, if the temperature does not drop for more than three days, the tissues of our body can suffer from hypohydration and lack of oxygen.

For example, when the temperature rises, there is a sharp expansion of blood vessels. This is necessary to maintain systemic blood flow, but at the same time it is fraught with a drop in pressure and the onset of collapse. Of course, this does not happen in the first hours, but the higher the temperature and the longer it does not fall, the greater the likelihood of negative consequences.

When fluid is lost through increased sweating, the volume of blood circulating in the body decreases and its osmotic pressure increases, which leads to a disruption of water exchange between the blood and tissues. The body strives to normalize water exchange by reducing sweating and increasing body temperature. In the patient, this is expressed in a decrease in the amount of urine and an unquenchable thirst.

Increased respiratory rate and intense sweating also lead to increased carbon dioxide release and demineralization of the body, and shifts in the acid-base balance may be observed. As the temperature rises, tissue respiration worsens and metabolic acidosis develops. Even increased breathing is unable to satisfy the increased oxygen needs of the heart muscle. As a result, myocardial hypoxia develops, which can lead to vascular dystonia and extensive myocardial infarction. Long-term high temperature in an adult leads to depression of the central nervous system, disruption of homeostasis, and hypoxia of internal organs.

It is important to remember that if febrile mercury levels are observed for more than three days, such a temperature must be brought down. And the cause of such a condition must be established even earlier.

It happens that a high temperature does not go down in an adult. In such cases, it is necessary to consult a doctor. If the thermometer readings do not exceed 39℃, you can contact your local therapist, and if the temperature approaches 40℃ and antipyretics do not help, you need to call an ambulance.

Convulsions at high temperature in adults develop due to the fact that high temperature disrupts the regulatory processes in the structures of the brain. Reflex muscle contractions occur at different thermometer readings. For people with diseases of the central nervous system, sometimes a rise in the mercury column to 37.5℃ is enough, although, of course, most people have convulsions at a temperature of over 40℃. Convulsions can be clonic, when muscle spasms quickly give way to relaxation, and tonic, when the tone is maintained for a long time. Spasms can affect a separate group of muscles or the entire musculature of the body. Convulsive muscle contractions usually occur with a sharp rise in temperature or a decrease in blood pressure. A patient with convulsions cannot be left unattended, it is necessary to seek emergency medical care, since in such a condition respiratory failure and collapse can develop against the background of a sharp drop in pressure in the arteries.

Even without the development of convulsions, prolonged hyperthermia without periods of decreased temperature readings can lead to depletion of energy reserves, intravascular blood coagulation, cerebral edema - terminal conditions with a fatal outcome.

A rash after a high temperature in an adult can most often be caused by drug intoxication with antipyretic drugs. Basically, with all infections (measles, scarlet fever, typhoid, meningitis, etc.), the rash appears when the temperature has not yet dropped. Although there can be many reasons for the rash, including secondary syphilis. In addition, childhood infections such as rubella and chickenpox in adults often occur atypically, so rashes after a high temperature that appear in an adult must be shown to a doctor.

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Prevention

Preventing a high temperature means never getting sick. This is unrealistic, especially since a rise in temperature is a protective reaction, and healthy people with good immunity usually get sick with a high temperature. Usually, such diseases end faster than a long-term subfebrile condition with unexpressed symptoms.

To more easily tolerate a high temperature, it is necessary to eat well, exercise a lot, walk in the fresh air, dress for the weather and promptly sanitize foci of chronic infection.

If the temperature rises in a person suffering from diseases of the central nervous system or blood vessels and heart, it is necessary to prevent its uncontrolled rise and promptly seek medical help.

It is also advisable to avoid hyperthermia as a result of overheating, overloads and significant nervous tension. In hot weather, try to drink more clean water, wear a hat and do not stay in the open sun for a long time.

In addition, it is necessary to always have a suitable remedy for high temperature in your home medicine cabinet for yourself and your loved ones, and take it with you on hikes and trips.

Forecast

Basically, each of us has repeatedly had to endure diseases accompanied by high temperature. The overwhelming majority of such conditions have a favorable prognosis.

People at risk, suffering from convulsions and diseases that lower the temperature threshold, need to take timely measures, bringing down the temperature with suitable means and methods, which will also allow them to avoid complications.

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