Suffering from Mycoplasma pneumoniae infection Manifestations of the body

Mycoplasma pneumonia is a common infectious disease of the lungs in childhood, and its clinical manifestations are diverse, in addition to causing lung inflammation, it can also cause serious complications of multiple systems outside the lungs, such as cardiovascular, gastrointestinal, skin, blood, neuromuscular and joint damage.

Recent studies have shown that Mycoplasma pneumoniae has common antigens with organs outside the respiratory tract, such as the membrane protein of Mycoplasma pneumoniae has strong antigenicity, and the antibodies produced by this antigen stimulation can cause organ damage. In addition, T lymphocyte function decreases after Mycoplasma pneumoniae infection, and allergic reactions can occur. Circulatory complications are related to immune function as evidenced by cardiac biopsy, and neurological complications are mostly caused by direct invasion, so it can be seen that the clinical manifestations of mycoplasma infection are far more complex than previously understood, especially its serious complications, which often mask up its mild respiratory symptoms (primary disease), resulting in misdiagnosis, and this is also the case in our clinical practice: the comorbidities of mycoplasma infection involve multiple systems, which are described below.

1. Respiratory system

After Mycoplasma pneumoniae infects the respiratory tract, it can have no symptoms, or only cause mild symptoms of upper respiratory tract infection, so many patients are often diagnosed with "upper sense", "bronchitis", etc., and only 3%~10% of the real manifestations of "pneumonia" are present.

Pleural effusion, previously thought to be rare in patients with mycoplasma infection, has been shown to be present in approximately 20% of patients with lateral chest x-rays in such patients. Pleural effusions are mostly serous and usually resorbate spontaneously within a few weeks, and sometimes Mycoplasma pneumoniae can be cultured.

Respiratory tract infections caused by mycoplasma can also manifest as lung abscess, pulmonary cele, respiratory distress and so on in some cases.

2. Nervous system

The frequency of central nervous system complications in mycoplasma infection accounts for about 0.1% of total infections and can occur in up to 7% of hospitalized patients.According to statistics, complications of the central nervous system are more common in children, and the severity of respiratory and nervous system lesions is not parallel.

Central nervous system involvement, including meningoencephalitis, nonpurulent meningitis, brainstem encephalitis, transverse myelitis, etc., has no specific symptoms and may present with headache, fever, lethargy, ataxia, focal cranial nerve palsy orepilepsyWait. In such patients, mycoplasma infection can be confirmed by serological tests, most of them can be isolated from the pharynx, and a few patients can isolate Mycoplasma pneumoniae from cerebrospinal fluid, and the recovery of these patients is very slow, often taking several months, and about one-third of patients still have some neurological deficit after recovery. Pathological examination usually includes perivascular cell infiltration and demyelination, punctate hemorrhage, and regional tissue necrosis.

3. Cardiovascular system

In the past, mycoplasma infections were thought to be very rare in the cardiovascular system, but in recent years they have been found to be present in 4.5% of all infections and can coexist with central nervous system complications. The main manifestations are myocarditis, pericarditis, myocardial ischemia, cardiac dysfunction, etc. Some patients do not have any cardiac symptoms, but ECG and cardiac enzymes suggest myocarditis. The severity of the disease can vary greatly, and most patients are mild and return to normal.

4. Blood system

Hematologic complications occur in more than 50% of patients with mycoplasma infection, the most common being hemolytic anemia of varying severity lasting several weeks, and elevated reticulocytes in 64% of patients. Again, the occurrence of this type of hemolytic anemia is thought to be autoimmune-related. The number of white blood cells in mycoplasma infection is generally normal, 1/3 exceeds 10109/L, and only a few patients have leukemia-like reactions, and the white blood cells can reach about 45109/L, which needs to be identified.

5. Digestive system

In patients with mycoplasma pneumonia, 12%~24% of patients can have different degrees of gastrointestinal symptoms in the early stage of the course of the disease, including anorexia, nausea, vomiting, diarrhea, etc., and some patients have abnormal liver function, and often see the increase of transaminase and alkaline phosphatase.

6. Urinary system

In recent years, it has been shown that urethritis caused by mycoplasma is not uncommon. Three cases of mycoplasma pneumonia complicated by acute glomeruli have been reportednephritisOne of these cases also had immune complexes containing mycoplasma antigen detected in his glomeruli. in a part of the renal pelvisnephritisIn patients, isolation and culture of the organism and serological testing have been shown to be due to mycoplasma infection.

7. Musculoskeletal system

In patients with Mycoplasma pneumoniae infection, about 15%~45% of patients may have obvious muscle pain and arthralgia, and even arthritis.Arthritis can occur in all age groups, and joint symptoms usually begin about 1 week after the onset of respiratory symptoms, with local redness, swelling, fever, erythema, subcutaneous nodules, and synovial effusion. It is often polyarticular and migratory, often involving larger joints. Joint symptoms are usually transient and sometimes resolve during the acute phase of respiratory infection. However, in some cases, respiratory symptoms are very mild or even unnoticed, while joint symptoms are very severe and recovery is slow, sometimes lasting about 10 months or even one and a half years. In the serum of arthritic patients, rheumatoid factor is often detected, sometimes some complement components are reduced, and anti-chain "O" is usually normal. It is thought that mycoplasma is mainly the result of autoimmune processes that cause inflammation in the joints.

8. Skin and mucous membranes and others

About 25% of patients diagnosed with mycoplasma infection based on isolation culture and serum blood tests showed skin and mucosal lesions.The rash may appear at the same time as fever or months after fever. It is mostly seen on the limbs first, and then appears on the trunk and face one after another, generally lasting for 7~10 days, and the rash is mostly red maculopapular rash, and there are also measles, scarlet fever-like.