High fever

Introduction High fever means that the body temperature exceeds 39.1 °C. Hyperthermia is divided into acute hyperthermia and long-term hyperthermia. Acute hyperthermia is more common in infectious and allergic inductive diseases, while long-term hyperthermia can be seen in sepsis, Salmonella infection, tuberculosis, rheumatic fever, and juvenile rheumatism.

Cause

(1) Acute high fever

Infectious disease

Early acute infectious diseases, acute infectious diseases of various systems.

2. Non-infectious diseases

Heat syndrome, neonatal dehydration fever, intracranial injury, convulsions and epileptic seizures.

3. Allergic reaction

Allergies, allogeneic serum, vaccination response, infusion, transfusion reactions, etc.

(2) Long-term high fever

Common disease

Sepsis, Salmonella infection, tuberculosis, rheumatic fever, juvenile rheumatism, etc.

2. Rare disease

Malignant tumors (leukemia, malignant lymphoma, malignant histiocytosis), connective tissue disease.

an examination

Related inspection

Hemolytic Japanese Encephalitis Complement Binding Test Exo-Fiji Reaction Anti-Cytosidase Test Urine Conventional Hyaluronidase

Fever is a common symptom of many diseases, so it is necessary to investigate and analyze the fever patients in order to find out the cause. Generally, it must be done from the following aspects.

(1) Detailed and accurate collection of medical history, pay attention to age, disease season, epidemiological history, history of infectious disease exposure, history of vaccination, rapid onset, length of disease, heat type and accompanying main symptoms.

Newborns can have dehydration heat. Infants and young children in the south, summer heat can occur when the heat is hot. In winter and spring, respiratory infections, epidemic cerebrospinal meningitis, measles and other common occurrences; in summer and autumn, acute enteritis, bacillary dysentery, Japanese encephalitis, typhoid fever, etc. are more common. Infectious diseases often have a history of epidemiology, and should be carefully asked about the history of exposure.

Pediatric respiratory infections, acute infectious diseases, etc. are often onset, and the course of disease is shorter. Tuberculosis, typhoid fever, blood diseases, rheumatic fever, heat syndrome, bacterial endocarditis and other onsets are mild, and the course of disease is longer, often more than two weeks. Sepsis, acute miliary tuberculosis, deep abscess and other relaxation heat; typhoid fever, paratyphoid fever, typhus typhus as heat retention; malaria is mostly intermittent heat; leukemia, connective tissue disease, malignant tumor, etc., different types of heat, no certain law. The heat type is very important for the diagnosis of fever when it has not been treated with special drugs such as antibiotics and corticosteroids, but it has little diagnostic value for small infants and newborns.

When inquiring about fever, you should pay attention to the specific clinical manifestations of each system. For example, respiratory infections often have cough and shortness of breath. Digestive tract infections often have nausea, vomiting, abdominal pain, and diarrhea. Urinary tract infections include frequent urination, urgency, and dysuria. Central nervous system disorders, vomiting, convulsions, coma and so on. Fever with jaundice common liver bacterial or viral inflammation, tumor; associated with sweating common in connective tissue disease, sepsis, etc.; with cold warfare are mostly bacterial infections such as sepsis, deep abscess. In the early stage, there are no specific clinical manifestations and signs, and combined with the characteristics of the history of the disease to consider typhoid, sepsis, tuberculosis and so on.

(2) Comprehensive and careful physical examination

The examination should be detailed and comprehensive, combined with medical history and symptoms, and then in-depth examination.

Oral in many fever patients, pathological changes are common. Such as tonsillitis can be seen tonsils redness or purulent secretion; herpes pharyngitis can be seen in the pharynx and other areas of herpes and ulcers; measles early in the buccal mucosa with Coriolis; diphtheria can be seen in the throat and tonsils have white pseudomembrane.

Pay attention to the distribution and morphology of the rash. Staphylococcus aureus, streptococcal infections are common with scarlet fever-like rash; blood diseases, epidemic cerebrospinal meningitis, epidemic hemorrhagic fever and other skin may have bleeding points; rheumatic fever can be seen in ring erythema; viral infection, connective tissue disease, sepsis Bacterial endocarditis, histiocytosis X, mucocutaneous lymph node syndrome and many drugs can cause rash, but their morphology and appearance are different.

People with good mental state during high fever are often mildly infected. Such as lethargy, apathetic, unconscious, with meningeal irritation, suggesting intracranial infection. In the early stage of infant intracranial infection, meningeal irritation is often not obvious, but the performance is apathy, lethargy, irritability, nervous or full of sputum, etc., must be alert to intracranial infection.

Hepatosplenomegaly is common in leukemia, connective tissue disease, inflammation of the hepatobiliary system, typhoid fever, sepsis, malaria, and tumors. Lymph node enlargement can be seen in blood diseases, infectious mononucleosis, mycoplasma infection, lymph node syndrome of the skin and mucous membranes. Local lymphadenopathy, tenderness, should pay attention to find adjacent areas with or without inflammatory lesions.

(3) Laboratory inspection

First check the general, according to the general screening results, and then decide to further check the project, try to avoid the purposeless "casting" type inspection.

Common tests for blood, urine, and feces are preferred items for screening. The total number of white blood cells and neutrophils are increased, and more are considered bacterial infections; those with reduced weight are more viral or bacilli infections. If you suspect sepsis, intestinal and urinary tract infections, you need to send blood, feces, and urine separately. In addition to routine examinations, various puncture fluids are sometimes sent for culture or smear examination. For example, meningococcal smear and cerebrospinal fluid smear in patients with epidemic cerebrospinal meningitis can find meningococcal bacteria, blood smears for malaria can find malaria parasites, and diphtheria pseudomembrane smears to check diphtheria bacilli.

If necessary, check the fatda reaction, the external Fischer reaction, the heterophilic agglutination test, the condensation set test, etc., to help the differential diagnosis. Rheumatoid fever or rheumatoid disease was examined for anti-streptolysin O or rheumatoid factor, respectively. Patients with suspected viral infections may have early rapid diagnostic tests for immunological aspects. Patients with repeated infections caused by immunodeficiency disease can be used for serum immunoglobulin and cellular immunity and complement determination. Blood diseases should be checked for bone marrow. Suspected tuberculosis requires a tuberculin test. Patients with suspected biliary tract infections are often examined and cultured for duodenal drainage, and often have meaningful results. In short, the relevant examinations can be carried out according to the condition of the disease, but it is necessary to pay attention to the analysis of the results of the examination, to eliminate false positives or false negatives caused by errors and pollutions such as sampling or operation.

(4) X-ray and other inspections

Chest X-rays help diagnose lung and chest diseases. Others, such as malignant tumors, can be selected for CT, nuclear magnetic resonance, angiography, radioisotope, B-mode ultrasound, and living tissue according to the site, which is also necessary.

Differential diagnosis

Differential diagnosis:

(1) Infectious diseases

Septicemia

Pathogenic bacteria are released through damaged skin, mucous membranes or from a infected foci, and enter the bloodstream through lymphatic vessels and veins to produce and produce toxins. Common are Staphylococcus aureus sepsis and Gram-negative septicemia. The former has an acute onset, sudden chills, high fever, and hot type. It is characterized by pleomorphic rash, skin mucosal bleeding, joint swelling and pain, endocarditis and migraine lesions. Peripheral blood leukocytes and neutrophils were significantly elevated. Gram-negative septicemia is often a relaxation heat, intermittent heat or bimodal fever, which may be associated with relatively slow pulse, necrotic rash, hepatosplenomegaly and septic shock. In some patients, peripheral blood leukocytes may not be high. Multiple blood cultures and bone marrow cultures are helpful for the detection of pathogenic bacteria. It is generally believed that the best time to take blood should be before the use of antibiotics and when chills and high fever occur. A positive lysate test (LLT) indicates the presence of Gram-negative bacilli endotoxin, but also false positives and false negatives.

2. Tuberculosis

(1) Miliary tuberculosis

There may be symptoms of high fever, chills, shortness of breath and systemic poisoning, and chest radiographs show diffuse nodules.

(2) invasive pulmonary tuberculosis

May have fever, cough, hemoptysis, fatigue, reduction, weight loss, night sweats, sputum tuberculosis culture can be positive, chest radiograph shows one or both sides of the lung patch or spotted shadow, and can have fibrosis and calcification .

(3) Extrapulmonary tuberculosis

Including tuberculous meningitis, tuberculous pleurisy, peritoneal tuberculosis, lymph node tuberculosis, kidney tuberculosis and so on. Clinical symptoms of systemic poisoning and associated symptoms. The white blood cells are generally normal or slightly elevated, and may have an increase in erythrocyte sedimentation rate, and the tuberculin test is positive. Diagnostic treatment is effective.

Typhoid fever

The onset is slow, the body temperature rises in a trapezoidal shape, and the retention type continues to be hot, accompanied by apathy, relatively slow pulse, and rose rash. Typical cases may have splenomegaly and hepatomegaly at 1 week of the disease. The white blood cell count was reduced, the fatda reaction was positive, and the typhoid bacillus was isolated from the blood culture. In recent years, due to the widespread use of antibiotics, atypical cases of typhoid fever have increased, complications have increased, and types are complex, which should be taken seriously.

4. Epidemic hemorrhagic fever

Rats are a source of infection and can be popular in spring and summer and autumn and winter. The clinical classification is divided into fever, hypotension, oliguria, polyuria, and recovery. The onset of fever is rapid, the body temperature is generally between 39 °C ~ 40 °C, the heat type is more relaxation heat, accompanied by headache, eye pain, eyelid pain, blurred vision, thirst, nausea, vomiting, abdominal pain, diarrhea, etc. The face and eyelid area are congested, the upper chest is flushed, and the underarm is visible at the bleeding point. Leukocytosis, lymphocytosis, and decreased platelet count. Diffuse exudative changes can occur in chest radiographs.

5. Malaria

The incidence rate is high in summer and autumn, and there is obvious chill before high fever. The body temperature can reach above 40 °C, accompanied by a lot of sweating, splenomegaly and anemia, and the white blood cell count is low. For patients suspected of malaria, such as multiple blood smears or bone marrow smears have not found malaria parasites, try chloroquine for diagnostic treatment.

6. Infective endocarditis

In patients with congenital heart disease or rheumatic heart valve disease, or after cardiac surgery, unexplained high fever accompanied by generalized fatigue, progressive anemia and embolism, physical examination of bleeding spots on the skin, mucous membrane, nail bed, etc. Cardiac auscultation has new murmurs or changes in the nature of the original murmur, or accompanied by arrhythmia, the possibility of considering this disease, repeated blood culture helps to confirm the diagnosis.

7. AIDS

If there are two or more of the following high-risk groups, the AIDS may be considered:

(1) intermittent or continuous fever for more than 1 month;

(2) generalized lymphadenopathy;

(3) Chronic cough or diarrhea for more than 1 month;

(4) Weight loss of more than 10%;

(5) Repeated herpes zoster or herpes simplex infection;

(6) Oropharyngeal Candida infection.

Further diagnosis requires HIV antibody and HIV RNA detection as well as CD4+ T lymphocyte counts.

8. Influenza

Good winter and spring, easy to outbreak. More often with high fever, accompanied by headache, fatigue, body aches, body temperature can reach 39 ° C ~ 40 ° C, for 2 to 3 days, retreat, nasal congestion, runny nose, sore throat, cough, blood stasis or combined bacterial infection Pus, a small number of patients may have difficulty breathing or gastrointestinal symptoms. The white blood cell count is normal, reduced or slightly increased, and the proportion of lymphocytes can be increased.

9. SARS/Severe Acute Respiratory Syndrome (SARS)

The pathogen may be a new type of coronavirus, the source of infection for its patients and carriers of latent pathogens, with close air droplets and close contact as a means of transmission. The clinical process is rapid, and fever is the first symptom. The body temperature is generally above 38 °C, which may be accompanied by headache, general malaise or muscle pain. It may have dry cough, and severe cases may have shortness of breath or even respiratory distress. White blood cell counts generally do not increase or decrease, often with reduced lymphocyte counts. Chest X-rays showed varying degrees of patchy, patchy infiltrating shadows or reticular changes. This type of "atypical pneumonia" is different from atypical pneumonia known to be caused by Mycoplasma pneumoniae, Chlamydia pneumoniae, Legionella and common respiratory viruses. It is highly contagious, aggregating, has a strong clinical manifestation, and its disease progresses rapidly and is harmful. And other characteristics, especially those older than 50 years old or with a combination of underlying diseases have a poor prognosis.

10. Legionnaires' disease

It is an acute respiratory infection caused by Legionella. The mode of transmission is mainly inhaled by water supply system, air conditioning and atomized inhalation. People who are older and have low immunity are prone to develop. Onset is characterized by high fever, chills, fatigue, myalgia, dry cough, diarrhea, and severe cases may have difficulty breathing and neuropsychiatric symptoms. The white blood cell count is increased, and the neutrophil nucleus is shifted to the left, which may be associated with renal dysfunction. In the early stage of chest radiograph, peripheral plaque-like alveolar infiltration, followed by lung consolidation, the lower lobe is more common.

11. Acute bacterial pneumonia

It is inflammation of the lungs caused by bacterial infection. According to the extent of lesion involvement, it is divided into lobar pneumonia and bronchial pneumonia. The patient has fever, cough, sputum and purulent sputum, chest radiograph showing inflammatory infiltrative shadow in the lung, white blood cell count or neutrophil increase, or qualified sputum culture can isolate meaningful pathogens.

12. Local infection

Liver abscess, biliary tract and acute genital tract infection, intra-abdominal abscess are more common, acute infection can cause high fever, fatigue, backache, abdominal pain, nausea, vomiting and other accompanying symptoms, should be observed changes in physical signs, and repeated laboratory Inspection and auxiliary examinations are of great value for the discovery of lesions.

13. Fungal infections

Patients with long-term use of antibiotics, glucocorticoids or immunosuppressive agents are prone to opportunistic fungal infections. Clinical manifestations of fever can continue, with chills, night sweats, anorexia, weight loss, general malaise or cough, hemoptysis, etc., should consider the possibility of oropharynx or deep fungal infection, conditional fungal culture or antifungal drug observation treatment.

(2) Non-infectious diseases

1. Systemic lupus erythematosus (SLE)

More common in young women, fever has a longer duration. Acute exacerbation has high fever, body temperature can be as high as 39 ° C ~ 40 ° C, more with joint pain, skin lesions, facial butterfly erythema, sun allergy, anemia, fatigue, limb arterial spasm, bleeding points. Clinical and laboratory tests showed liver, kidney, heart, lung and other multiple organ damage, hemolytic anemia, white blood cells, thrombocytopenia, increased erythrocyte sedimentation rate, positive antinuclear antibody (highest positive rate), anti-smooth muscle antibody positive (specific Highest), found lupus cells in the bone marrow and peripheral blood, or positive for skin biopsy.

2. Rheumatic fever

Many adolescents often have a history of acute pharyngitis or tonsillitis before onset. It is a systemic allergy caused by infection with hemolytic streptococcus. Most patients have fever, most of them are irregular heat, often accompanied by migratory joint pain, increased heart rate, and arrhythmia. Some patients have ring erythema on the trunk and inside the limbs. Subcutaneous nodules can be seen in the affected joint area, which is hard and painless and does not adhere to the skin. Laboratory tests for accelerated erythrocyte sedimentation rate, increased mucin, and increased anti-streptolysin "O" titer.

3. Dermatomyositis

The clinical manifestations are high fever, with general discomfort, extreme fatigue and symmetry of muscle pain and tenderness. Patients cannot sit and stretch.

4. Adult Still's disease

The old name "variant subsepticemia" is characterized by intermittent high fever, rash and joint symptoms. In addition, there are lymphadenopathy, hepatosplenomegaly, white blood cell count, erythrocyte sedimentation rate, rheumatoid factor and anti-nuclear antibody are negative, repeated blood culture negative, antibiotic treatment is invalid, glucocorticoid treatment is effective.

5. Blood disease

Acute leukemia, malignant lymphoma, malignant histiocytosis, myelodysplastic syndrome, acute aplastic anemia, multiple myeloma and other blood diseases can be characterized by long-term fever, and the fever is mostly relaxation, intermittent or periodic. The course of fever can be delayed from several weeks to several months. Patients with varying degrees of pale, bleeding tendency, hepatosplenomegaly or lymphadenopathy often require bone marrow aspiration, lymph node biopsy, etc. Can be diagnosed.

6. Various malignant tumors

Tumor patients may have moderate or moderate fever, such as digestive tract, respiratory malignant tumor, osteosarcoma, renal cancer, adrenal cancer, and patients with progressive wasting, loss of appetite and symptoms of diseased organs .

7. Drug fever

Patients with fever use antipyretic analgesics, sulfonamides, certain antibiotics or sleeping pills, etc., but the fever continues to rise or rise again, or if there is no fever before, there is no new evidence of infection, accompanied by pleomorphic rash. Joint pain, lymphadenopathy and eosinophilia, patients generally good condition, no symptoms of poisoning, should consider the possibility of drug fever. Suspected drugs can be stopped under close observation. If the body temperature drops to normal within a few days, a diagnosis of drug fever can be made.

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