Differential diagnosis: methods and basic principles of examination
What is the differential diagnosis of diseases? This is a method of "sorting" the symptoms that have appeared for making the only correct diagnosis. It is no secret that even experienced doctors, under certain conditions, have doubts that need to be confirmed or disproved. The reason for the differential diagnosis is the appearance of many syndromes - icteric, arterial hypertension, cardialgia, obstruction, and many others that are characteristic of several diseases at once.
Differential diagnosis of cardialgia
Pain in the heart area is found in patients' complaints very often, because they are a symptom of many diseases. Even banal osteochondrosis can give similar symptoms. Heart pain can be either true (cardiac) or false, associated with other diseases and serving as a secondary symptom.
It is important to make a diagnosis in a timely manner, since any delay can lead to complications of the condition, including death. It is right to start any examination with the collection of information - an anamnesis, which can "weed out" a whole diagnostic series of diseases already at the initial stage.
The role of history in the diagnosis
During the initial examination of the patient, it is necessary to pay attention to his age, gender, emotional state, complexion. An important place in the survey is given to bad habits and other damaging factors, such as working conditions. To diagnose stenocardia, we need a competent differential diagnosis of internal diseases with other conditions that mimic the disease.
An enlarged thyroid gland, thoracic osteochondrosis, intercostal neuralgia, pleurisy, an inflammatory process in the shoulder joint, and much more can cause chest pain. If, during an objective examination, angina is diagnosed (or, on the contrary, excluded), the doctor makes the appropriate diagnosis. Prior to additional laboratory and hardware examination methods, it is considered preliminary. Any mistake is dangerous for the patient.
Additional research methods
All patients who complain of pain in the heart area, especially those who made similar comments for the first time, should be referred for additional research.
- general (expanded) blood test;
- blood for glucose, reactive protein, lipids, rheumatoid components, etc .;
- to eliminate syphilis, it is necessary to conduct a Wasserman reaction;
- ECG before and after exercise;
- chest X-ray (the goal is to determine the boundaries of the lungs, heart, and possible inflammatory foci) and the thoracic spine;
- in case of suspicion of diseases of the abdominal cavity - ultrasound examination of the relevant department;
- with certain indicators, echo, coronary angiography, FGS are possible.
Differential diagnosis of infectious diseases should be based on objective and laboratory methods of examination. The most frequent and significant today are jaundice and hemorrhagic syndromes.
The collected history of contact with obvious and possible sick people, traveling to other countries, as well as existing co-morbid chronic diseases greatly simplifies the task of making a correct diagnosis.In addition, it is important to find out whether the patient took any medications, whether he had contact with poisons. Examination of the skin for the presence of rashes and scratching, palpation examination of the liver is also important. In a word, the more information we managed to collect, the more accurate the primary differential diagnosis will be.
Jaundice syndrome does not always indicate a direct liver disease. Mechanical blockage of the bile ducts, problems with the pancreas, etc. are possible. A characteristic feature of true hepatitis is dark urine color and discoloration of fecal masses, and this symptom may become primary. The color of the skin with various causes of liver syndrome varies from light yellow to yellow-red (with a lesion of the parenchyma). Laboratory studies of biological material with true hepatitis reveal a large amount of bilirubin in the free state.
Differential diagnosis of diseases involving hemorrhagic syndrome is very important. It has epidemiological significance.As a rule, such manifestations are characterized by severe febrile conditions with the rapid development of the overall clinical picture.
Diseases accompanied by hemorrhagic syndrome are conventionally divided into two groups. In the first, it is the main feature, in the second - the accompanying one. Laboratory tests allow to determine the causative agent of the disease. Since viruses tend to mutate, each new locus found is usually called the place of its origin (Crimean, Omsk, Rocky Mountains, Ebola).