Since the body temperature of a healthy person is constant, with slight fluctuations in the tenths of a degree, its increase on a larger scale always indicates the presence of inflammatory processes in the body, including an infectious one. The level of heat of the human body in dynamics is called the temperature curve, which is often identified with fever (a temporary increase in temperature).
The graphical construction of the patient’s temperature curve plays an important role in the diagnosis and prognosis, and is also necessary for an objective assessment of the course of the disease. Body temperature is measured at least twice a day: in the morning and evening hours, and at the height of an infectious disease - several times a day.
What are the types of temperature curves?
They are distinguished by the degree of increase. The following types of temperature curves exist: subfebrile - not exceeding 38 ° , medium or moderate - 39 ° , pyrethic - up to 41 ° , superpyretic - over 41 ° (extremely rare phenomenon).
The types of temperature curves for infectious diseases determine the classification of fever depending on the degree of diurnal temperature fluctuations. We list these types of fever (types of temperature curves): constant, laxative, intermittent, depleting, recurrent, wave-like and inverse.
Persistent fever characteristic
It is observed with such infectious diseases as typhoid fever and typhus, pneumococcal pneumonia. Graphically, constant fever is displayed as trapezoidal types of temperature curves, a characteristic feature of which is the fluctuation of body temperature by no more than 1 °, while the body temperature remains at a high level for a long time - around 39 °. As the disease recedes, the temperature curve can decrease both sharply and gradually.
Characteristics of relapsing fever
Laxative types of temperature curves are observed with purulent diseases, catarrhal pneumonia, typhoid fever, and also with tuberculosis. Body temperature is also kept at a high level, however, in contrast to constant fever, in this case, the amplitude of fluctuations in the morning and evening temperatures reaches 2 degrees, thus falling to 38 ° C, but not returning to normal values.
Intermittent fever
An intermittent, or laxative, fever most often expresses the type of temperature curve of malaria. It is accompanied by sharp increases in body temperature (febrile), which are replaced by afebrile periods, that is, with normal temperature indicators. The time intervals between attacks of febrile fever can last from one to 3 days, while the patient feels chills when the temperature rises, and when it decreases, severe sweating is observed.
A laxative fever cannot unconditionally indicate the presence of malaria in a patient, this type of febrile fever is actually inherent in many infectious diseases, such as recurrent epidemic typhus, focal purulent infections, soda (infection transmitted to a person from a rat bite), liver disease, and others.
Exhausting fever
The debilitating type of fever is accompanied by large ranges between morning and evening temperature values, the amplitude of oscillations reaches 3-5 ° C. The period of febrile condition can last several days, after which normalization of the temperature regime occurs due to the weakening of the disease. Exhausting fever is a sure sign of septic, purulent infections, also occurs with tuberculosis.
Relapse fever
The characteristic of this type of fever lies in its name. This means that the period of pyrexia (elevated body temperature) with a duration of several days returns again after a predetermined period of aporexia. Thus, the patient has a clear fever for several days with insignificant amplitude fluctuations in the morning and daytime temperatures, then lulls for several days, the body temperature normalizes, but then the picture repeats again up to 4-5 times. Such a temperature curve is characteristic of infectious diseases caused by spirochete bacteria, an example of this type of disease is relapsing fever.
Wave fever
A wavy temperature curve is a type of relapsing fever, since it also has periods of alternating febrile remission. However, the wavy curve is characterized by smoother transitions, showing a gradual increase in temperature over several days, and then several days it also gradually decreases. Such a fever is accompanied by a course of brucellosis.
Inverse fever
Inverse, or perverse, fever differs from other types of temperature curves in that the temperature peak does not occur in the evening, but rather in the morning. Such a course of febrile condition is characteristic of prolonged sepsis and advanced forms of tuberculosis, as well as viral diseases.
Abnormal fever
Irregular fever does not have a clear schematic manifestation. It includes all the main types of temperature curves at once. The amplitude of fluctuations in temperature values can be varied, with different periodicities. Nevertheless, the atypical form of the temperature curve is most common, accompanying not only infectious diseases, but also various stages of rheumatism, flu, dysentery, pneumonia, etc.
Regardless of what types of temperature curves during fever occurred in a patient, fever goes through three main stages:
- Stage of temperature increase. Under the influence of pyrogens (in the case of infectious diseases, this is an external factor, namely various pathogenic bacteria and viruses), the so-called "set point" in neurons shifts. Thus, the heat transfer regime of the body is violated, and the available temperature is currently considered lower than necessary, as a result of which the body actively raises its temperature.
- Temperature maximum (apogee). Body temperature continues to increase to the level at which the "set point" has shifted, at this point the temperature maximum is reached, an equilibrium is established between the generation and release of heat.
- Remission occurs when the action of pyrogens weakens, and the then elevated body temperature is perceived by the body as excess. The process of enhanced heat transfer begins and the installation point returns to its previous level.