Non-clostridial myonecrosis

Introduction to non-C. difficile muscle necrosis Non-clostridiummyonecrosis is a purulent infection caused by obligate anaerobic Streptococcus pneumoniae with muscle necrosis as the main lesion. Local lesions are characterized by intramuscular cellulitis and cellulitis in the intermuscular space. Therefore, it is also called anaerobic streptococcal myositis. The lesion is more limited, and the necrotic muscle is often mixed with the muscles that still have vitality. The necrotic tissue is completely removed, and the wound is fully drained, which is a key measure for a good prognosis. basic knowledge The proportion of illness: 0.0025% Susceptible people: no special people Mode of infection: non-infectious Complications: anemia, renal failure

Causes of non-C. difficile muscle necrosis

(1) Causes of the disease

The pathogen of anaerobic streptococcal myositis is Streptococcus pneumoniae, which is widely found in nature and is one of the normal flora of the human oral cavity, intestinal tract and genitourinary tract. It belongs to the conditional pathogen and has 9 Species, important in surgical infections are anaerobic digestion of P. acerobius, P. micros, P. asaccharolyticus and Streptococcus pneumoniae (P. Magnus), they often form mixed infections with aerobic bacteria (such as group B streptococci, enterobacter, staphylococcus, etc.) or other anaerobic bacteria (such as Bacteroides), the main cause of which is strong exotoxin and A range of highly active enzymes.

More polluted trauma and surgery are the most common predisposing factors. Local muscle ischemia and hypoxia are also likely to induce this disease.

Anaerobic streptococcal myositis can also spread from infections in adjacent tissues and organs. For example, the spread of periodontal suppurative infection can lead to necrosis of facial and neck muscles. Patients with digestive streptococcal myositis often have a system that leads to low immune function. Sexual diseases, such as diabetes, malignant tumors, chronic renal failure, chemotherapy, immunosuppressive agents, malnutrition, etc., some patients have no cause of morbidity, called idiopathic cases.

(two) pathogenesis

Streptococcus pneumoniae breeds in anaerobic lesions to produce powerful exotoxins and a series of highly active enzymes such as hyaluronidase, collagenase, elastase, plasmin, etc., causing tissue necrosis, anaerobic digestion Streptococcus can also break down cellulose and decompose sugar in tissues and organs by anaerobic glycolysis to produce gas and malodorous hydrogen sulfide. Digestive streptococci spread in the muscle space, and interstitial edema and inflammatory cell infiltration can be seen under the microscope; The connective tissue along the muscle spreads to both ends, which can affect the full length of the muscle. The central part of the muscle cells are necrotic, and sometimes only the incomplete connective tissue fiber frame remains. In the meantime, there are piles, chains, and stretched Gram. Positive cocci and a large number of dead polymorphonuclear leukocytes, the endometrium and muscle fascia adjacent to the necrotic area were significantly congested, hemorrhage and blood vessel thrombosis, and focal muscle cell necrosis.

Non-C. difficile muscle necrosis prevention

This disease is purely endogenous infection, the human body can not be sterile, such anaerobic bacteria inhabit a variety of mucosa, protect the integrity of the mucosal barrier; maintain the micro-ecological balance of bacteria; in particular, pay attention to timely correction of systemic and local defects Blood, hypoxia, and removal of deep necrotic tissue and foreign bodies are essential.

Non-C. difficile muscle necrosis complications Complications, anemia, renal failure

1. Anemia.

2. Severe cases may have liver and kidney failure.

Non-C. difficile muscle necrosis symptoms Common symptoms Trauma edema severe pain severe pain

It usually occurs 2 to 3 days after trauma or surgery, and the course of disease progresses slowly.

Local symptoms

(1) Swelling, severe pain, and serous exudation: the local pain of the improvement tends to increase, the patient feels swollen, severe pain, and there is plasma-like fluid exudation and stench.

(2) blister formation: If the infected muscle is superficial, the skin may have edema, pale or even serous blister, otherwise there will be only tenderness and mild swelling.

(3) pronunciation: When mixed with aerobic and anaerobic bacteria, there may be pronunciation.

2. Systemic symptoms of fever, body temperature up to 39 ° C, may be associated with liver and kidney dysfunction, systemic poisoning symptoms, urine protein positive and tube type.

Examination of non-C. difficile muscle necrosis

Peripheral blood

(1) White blood cell count: white blood cell count increased with nuclear left shift.

(2) Red blood cell count and hemoglobin: there may be a decrease in red blood cells and a decrease in hemoglobin.

2. Bacteriology examination

(1) Smear of secretion: stained with smear of lesion secretion, microscopic examination of a large number of Gram-positive cocci, contributing to the preliminary pathogenic diagnosis.

(2) Fluorescence method and enzyme dyeing method detection: It has the advantages of fast, simple, sensitive and specific, and can detect mixed anaerobic bacteria to make mixed antibodies to expand the detection range.

3. X-ray film can sometimes be seen in the formation of gas in the muscle.

4. CT shows muscle swelling and air bubbles.

Diagnostic identification of non-C. difficile muscle necrosis

Diagnostic criteria

1. Diagnosis of traumatic history based on medical history, clinical manifestations and combined with pathogen examination.

2. The clinical manifestations of improved wound swelling, severe pain, and plasma-like fluid exudation with malodor.

3. A large number of Gram-positive cocci were observed on the smear of the pathogen examination secretion.

Differential diagnosis

The area of gas gangrene necrosis is large, and a large number of gram-positive capsular large bacilli in the secretion smear suggest Clostridium myositis.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.