Differential Diagnosis (DD) is an opportunity to accurately recognize a disease and prescribe the necessary therapy in each case, since many pathologies have the same symptoms, and the approaches and principles of treatment for diseases differ. Thus, such a diagnosis allows you to establish the correct diagnosis in a short period of time and conduct adequate treatment, and as a result, avoid adverse consequences.
The concept of DD
Let's look at an example of what it is. A patient comes to the doctor with a runny nose. It would seem that the diagnosis is known, and nothing needs to be clarified. However, DD is necessary due to the fact that it is not known what causes a runny nose: allergies, colds, or other factors. Thus, if the examination was carried out poorly, then the patient is treated unsuccessfully for chronic rhinitis for a long period, which is fraught with the occurrence of severeconsequences in the form of atrophy of the mucous membrane.
Quite serious complications may appear due to the lack of differential diagnosis of oncological pathology. According to statistics, about a third of all malignant neoplasms were not detected initially, and they were treated like another disease. The lack of timely detection of the cause is fraught with progression and aggravation of the pathology clinic. Thus, it is important not only to identify the disease and make a diagnosis, but also to conduct a DD, which is available thanks to the latest technologies and qualified specialists.
DD methods
Differential diagnostic methods consist of the following steps:
- First - taking an anamnesis, listening to complaints and identifying symptoms. The doctor analyzes the information received from the patient and forms an opinion about the causes that provoked the pathology, as well as dysfunctions in the work of some organs and systems. It should be remembered that patient questioning is an unreliable diagnostic method, since it does not reflect the real state of the individual, but is based on his subjective judgment.
- Second - direct examination using physical methods. As a result, the clinical picture of the pathology is more accurately determined.
- Third - laboratory diagnostics. It is considered a decisive stage in the differential diagnosis of the disease, since it detects abnormalities in the body.
- The fourth one is instrumental. At this stage, with great accuracy,severity, as well as the location of the focus of the disease. The following types of examinations are widely used and trusted by medical personnel: endoscopy, ultrasound, radiography, MRI, manometry, cardiography, CT, encephalography, ECG. In some cases, they do several studies using different equipment.
- Fifth - the final diagnosis is made.
In the modern world, specially designed programs for personal computers are beginning to become very popular, which allow you to partially or completely diagnose the disease, including differential, reducing the precious time for making a diagnosis.
DD Principles
There are certain principles of differential diagnosis by which the disease is determined:
- Comparison of manifestations of a certain syndrome. Allocate differences in the signs that are observed in the patient and in the clinic of the established disease.
- If the alleged syndrome has a special feature, and in the particular case under consideration it does not, then this is a different syndrome.
- If the doctor assumes a disease, and the patient has a symptom that is opposite to this disease, then this indicates that the patient does not have such a pathology.
And, for example, the principles of DD for abnormal development of children, formulated by V. I. Lubovsky, sound like this:
- Humanity is the timely creation of the conditions necessary for each small individual for the maximum development of histalents.
- Comprehensive study of children - the use of information obtained by all specialists in a collective review.
- Systemic and holistic study - the study of emotional-volitional behavior and cognitive activity of children.
- Dynamic study - when examining children, take into account not only the points that they can perform and know at the time of the examination, but also their ability to learn.
- Quantitative-qualitative approach when evaluating the completed task - to take into account not only the result obtained, but also the rationality of the chosen decisions, the method, sequence of actions, persistence in achieving the goal.
DD for abnormal development of children
Differential diagnosis of child development solves the following problems:
- Setting an accurate diagnosis, as well as determining the educational institution where the child's correctional and pedagogical education will be carried out.
- Clarification of the diagnosis, delimitation of similar conditions with different psychophysical abnormalities.
- Determining the means and ways of corrective work, as well as forecasting the opportunities for learning and development of the child.
Several areas of differential diagnosis should be highlighted:
- Intellectual impairment - mental retardation, mental retardation.
- Different forms of deficient development - these include disorders of the musculoskeletal system, vision and hearing.
- Violation of behavior and emotional sphere - psychopathy, autism.
To conduct DD, tests are used to help give the phenomenon being studied a quantitative characteristic and certain techniques, with their help, the levels of the psychological development of the child are determined.
How is DD done?
After collecting information about the patient, the doctor highlights the main and secondary symptoms of the disease. He then ranks them in order of importance. All signs of the disease are combined into syndromes. Differential diagnosis can be called the basis for diagnosing a specific disease. During its implementation, several stages are distinguished:
- Determination of the main syndrome that is observed in the patient, and compilation of a list of probable pathologies.
- A detailed study of all symptoms, and especially the leading one, as well as an assessment of the general condition of the individual, the clinical picture is specified.
- Comparison of suspected disease with all listed. As a result of this process, the main similarities and differences are highlighted.
- The information is being analyzed and systematized. This stage is called the most creative.
- Comparing all the data, unlikely pathologies are excluded. The only correct diagnosis is substantiated and set.
The success of the differential diagnosis of a disease lies in the ability to correctly compare objective examination methods and subjective data. Underestimation of any factor leads to a diagnostic error.
Methods for diagnosing caries
Pathological process in the tissues of the tooth, as a result of which cavity defects appear,called caries. Depending on its development, the choice of diagnostic method is also carried out. If caries is a stain and is asymptomatic, then it is almost impossible to detect it on your own. The doctor detects it using special equipment and tools. Types of differential diagnosis are identical to other medical methods of examination. To make a differential diagnosis, carry out:
- Visual diagnostics. The doctor examines the oral cavity, paying attention to spots and areas of roughness on the enamel. Using a probe, irregularities on the teeth are detected, and they are examined from all sides with the help of mirrors.
- Drying. This manipulation is carried out in order to diagnose the primary stage of the disease. The tooth is dried with cotton swabs. Damaged areas appear dull.
- Coloring. For carrying out, the so-called caries markers are used: fuchsin or methylene blue. Places damaged by caries, as well as their borders, become visible after dye treatment.
- X-ray. Diagnostics is considered effective in the following cases: to detect a deep tooth lesion, a latent form of the disease, caries located under the gum or between the walls of the teeth. However, it is not possible to detect the disease at an early stage. Damaged areas of tooth tissue in the picture have a lighter appearance, unlike he althy ones.
- Orthopantomogram. With its help, damage is detected, and an idea is obtained of the condition of all the teeth of an individual. This is a fairly accurate diagnostic method. For its implementationusing a low-dose dental tomograph.
- Thermodiagnostics. Cold or hot water is used to irrigate the damaged area of the tooth or apply cotton swabs, previously moistened with a liquid of different temperatures. Depending on the pain sensations of the individual, the presence of the disease is determined. If they pass after a few seconds, then this indicates caries, and if the pain bothers you longer, then the doctor may suspect pulpitis.
In addition, electrodontometry, transluminescence, etc. are used.
The need for DD for dental caries
It is impossible to perform a differential diagnosis of teeth using only an examination of the oral cavity. Therefore, the above methods are used to make an accurate diagnosis. The decision on their expediency is made directly by the attending dentist. The need for such a diagnosis is dictated by the fact that caries can be confused with other dental diseases. In order to distinguish caries from hypoplasia, staining is used, from pulpitis - thermodiagnostics, from non-carious lesions - x-rays. The disease in an advanced stage can provoke pulpitis, periodontitis, and surgery may be required.
Clinic and differential diagnosis of chronic forms of pulpitis
The following types of chronic pulpitis are distinguished:
- Fibrous - common, its predecessor is acute pulpitis. In an individual, pain sensations mainly occur during exacerbation. The doctor discovers a rather deep carious cavity. The tooth may differ in color from he althy ones. Exposure to cold causes pain that does not go away immediately after exposure is stopped. Tapping individual sections of the tooth is painless. This type of pulpitis is differentiated from acute focal, chronic gangrenous and deep caries.
- Gangrenous - pain appears from hot, as well as when changing temperatures. At the very beginning, it grows, and then, gradually subsides. An unpleasant odor is felt from the oral cavity. In appearance, the tooth is grayish in color, there is a deep carious cavity. The superficial layers of the pulp do not bleed. Percussion does not cause pain. Such pulpitis should be differentiated from chronic fibrous and chronic apical periodontitis.
- Hypertrophic - there are several clinical forms: pulp polyp and granulating. In the first case, the overgrown pulp tissue is covered with gingival epithelial tissues and is considered a late stage of pathology. In the second case, granulation tissue grows from the cavity of the tooth into a carious cavity. This type of pulpitis is typical for children and adolescents. When chewing food, bleeding appears, pain is felt when biting on solid foods. The tooth practically does not react to temperature stimuli. There are large dental deposits on the diseased side of the tooth, as the individual spares it when chewing. Differentiate with overgrown granulations from the perforation of the bottom of the tooth cavity and with the growth of the gingival papilla.
DD CAP
Consider the clinic and differential diagnosis of pneumonia that occurs outside the walls of the hospital, i.e. at homeconditions. It is also called outpatient. To select adequate therapy, it is desirable to establish a diagnosis in a timely and correct manner, since often the symptoms of pneumonia are identical to other respiratory pathologies, and the methods of their therapy are different.
In such cases, differential diagnosis is required to clarify the diagnosis. Pneumonia or pneumonia is a very serious disease. It can also end in death, so it is especially important to start treatment in a timely manner, the effectiveness of which depends on the correct diagnosis. With inflammation of the lungs, using DD, the following diseases are excluded that have a similar clinic at the very beginning of the onset of the pathology:
- Bronchitis. A prerequisite for the occurrence of both diseases are acute respiratory processes. Cough with sputum is present in both pneumonia and bronchitis. However, in the first case, the disease is more severe, general intoxication of the body is observed, the temperature rises, there are no whistling dry rales, on the contrary, wet rales occur.
- Lung cancer. Initial symptoms are similar. If pneumonia is suspected, a person is prescribed a course of antibiotic therapy. If there is no result after a week, the patient is examined to exclude or confirm oncology. Differential diagnosis of lung cancer is advisable to do at an early stage before the symptoms that occur when the tumor grows into nearby tissues and metastasizes.
- Tuberculosis. Diagnostic errors are often encountered when comparing this pathologyand pneumonia. General symptoms: severe intoxication of the body, the presence of sputum, pale integument of the dermis, temperature above 38 degrees, dry cough, accompanied by pain. The difference is observed according to the following criteria: there is no effectiveness of taking antibiotics in tuberculosis; tuberculin test for pneumonia is negative, and for tuberculosis, on the contrary, it is always positive; the results of a bacteriological study show nonspecific microflora in pneumonia, and in tuberculosis - mycobacteria (Koch's sticks); on an x-ray with pneumonia, local clear infiltrative shadows are visible, and with tuberculosis - these shadows are heterogeneous, there are foci of dropouts.
Thus, the differential diagnosis allows an accurate diagnosis to be made, and the treatment will be prescribed to the individual adequately, taking into account the pathogen that provoked this disease.
Conclusion
DD is a type of examination that provides an opportunity to avoid serious consequences and the appointment of ineffective therapy. Its use is especially justified in ambiguous and severe cases. Its significance lies in the fact that diseases that do not fall under certain signs and factors for establishing the correct diagnosis are excluded in a short period of time. Conducting differential diagnostics requires deep practical and theoretical skills, developed logical thinking from the doctor.
