Aspergillosis

Introduction to Aspergillosis Aspergillosis refers to chronic inflammatory lesions such as the skin, nails, external auditory canal, eyelids, bronchi, lungs, bones and meninges caused by pathogenic Aspergillus. It has recently been shown that certain aspergillins can cause cancer. The disease is mostly exogenous infection, mainly caused by inhalation of Aspergillus spores in the respiratory tract, causing aspergillosis in the lungs, or invading the bloodstream to spread to various organs of the body. basic knowledge The proportion of sickness: 0.00352% Susceptible people: no specific population Mode of infection: exogenous infection Complications: bronchiectasis, massive hemoptysis, sinus tachycardia, tympanic membrane perforation

Cause of aspergillosis

(1) Causes of the disease

Aspergillus is divided into 18 groups, 132 species and 18 varieties, most of which are non-pathogenic bacteria, which can cause human diseases: Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Aspergillus nidulans and nesting Pseudomonas aeruginosa, Aspergillus niger, Aspergillus variabilis, Aspergillus oryzae, Aspergillus oryzae, Aspergillus oryzae, Aspergillus oryzae, Aspergillus japonicus, Aspergillus oryzae, Aspergillus fumigatus, Aspergillus oryzae, Aspergillus oryzae, Aspergillus oryzae, etc. Aspergillus is the most common.

(two) pathogenesis

Aspergillus, the main infection route is the respiratory tract, and can invade the bloodstream to spread to the whole body, followed by traumatic skin inoculation, often invading the skin, mucous membrane, lung, brain, eye, ear, sinus, gastrointestinal tract, nervous system and bones. Inflammation and chronic granuloma changes, severe cases can occur sepsis, and even lead to death. In addition, Aspergillus can cause allergies, some aspergillus can cause acute poisoning and carcinogenesis.

Aspergillosis prevention

When working in an environment exposed to Aspergillus contamination, protective masks should be worn. For example, when rice is dropped into the eye during threshing, it is not necessary to wipe the eyes with force. It should be rinsed with saline in time to avoid corneal damage. Clean daily nebulizers such as shoes. When using furniture, food or machinery, it should be wiped with a damp cloth to prevent Aspergillus spores from flying and polluting the air. For articles with obvious Aspergillus growth, spray with formaldehyde solution or peracetic acid solution, avoid moldy peanuts. , fruit and other foods, for patients with more serious primary disease and commonly used antibiotics, corticosteroids and cytotoxic drugs, regular nasal swabs, sputum and other multi-channel fungal culture, once the Aspergillus invasion is found, the antifungal drugs are given treatment.

Aspergillosis complications Complications, bronchiectasis, massive sinusoidal tachycardia, tympanic membrane perforation

Complicated with bronchiectasis, massive hemoptysis, tachycardia, periosteal perforation, severe cases can be blind.

Aspergillosis Symptoms Common symptoms Chest pain, cough, tachycardia, chills, visual acuity, hemoptysis, appetite, lack of eyeballs, nasal congestion

1. Pulmonary aspergillosis is the most common, and there are several types.

(1) Parasitic type: including Aspergillus oryzae and parasitic bronchial aspergillosis.

1 Aspergillus oryzae: This type occurs in the presence of pulmonary cavities, such as tuberculous cavities, bronchial cysts, chronic lung abscesses or cystic bronchiectasis. Aspergillus can be parasitic in the cavity, forming Aspergillus balls, more males. In females, more than 30 years old, about 75% occur in the upper lobe of the lungs, the incidence of lower lobe is lower, Aspergillus usually appear in a single, can occur in the right lung or left lung, occasionally both lungs spread at the same time, mainly Symptoms are hemoptysis, cough, low fever, and more phlegm, followed by chest pain, night sweats, shortness of breath, weight loss, fatigue, poor appetite, etc., hemoptysis is an important symptom of this disease, the incidence rate is 50% to 85%, chest X-ray film has characteristics which performed.

2 parasitic bronchial aspergillosis: more common in tuberculosis after lobectomy, mild symptoms, mainly intermittent cough, cough, chest tightness, chest pain, no obvious fever and other general malaise, cough often occurs before bedtime and In the morning, it can be a paroxysmal cough, a foreign body sensation or even a suffocation in the lungs. When coughing, it often causes facial congestion. Until the block coughs out, it feels comfortable. In a small amount of mucous sputum, it can be mixed with mung bean size. Grayish white block or dark red bloody mass, with a musty smell.

(2) Tracheal pneumonia type: manifested as relaxation fever, chest pain, cough, cough, loss of appetite, fatigue, weight loss, general malaise, etc. If the Aspergillus invasion causes tissue necrosis, cavity formation, there is moderate to severe hemoptysis, It is viscous or mucopurus, and often has bloodshot sputum. There may be large gray-green granules in the sputum. Microscopic examination can detect hyphae and spores. Chest X-ray films have scattered flaky, nodules in the middle and lower parts of common lungs. Shaped or agglomerated shadows can also form voids, sometimes irregularly distributed fine granular nodular shadows, lesions can be unilateral or bilateral, and some cases may have a small amount of pleural effusion.

(3) allergic type: more common in brewing workers and farmers, can occur allergic symptoms, such as cough, cough, throat, chest tightness, shortness of breath, asthma-like episodes, lack of appetite, itchy eyes, tears, fever, night sweats, joints Pain, dizziness, and even collapse, etc., the symptoms of this disease usually disappear after 1 to 4 days after stopping contact with allergens. If you repeatedly contact allergens (allergens), the course of disease can be delayed for more than 1 month.

2. Aspergillus granuloma

(1) Aspergillus granulomatosis: Symptoms are similar to brain tumors. The course of the disease is slow. It may have intermittent chills, low fever, dizziness, headache, nausea, stuffy nose, cough, cough, loss of appetite, fatigue and similar upper respiratory tract infections. Symptoms, followed by headache, vomiting gradually increased, hemiplegia after several months or 1 year, neck stiffness, CT, magnetic resonance examination can find brain occupying lesions, but difficult to qualitative, often need to open craniotomy.

(2) paranasal sinus granuloma

There are two types of infiltrative and non-invasive types. The non-invasive type is characterized by increased nasal secretions, mucosal edema, thickening and granuloma formation. Aspergillus can be formed in the maxillary sinus. Infiltration can cause bone mass in addition to mucosal lesions. Destruction, upward can invade the eyelids and brain, eyeball or eyelid swelling and visual impairment, facial swelling and tenderness can appear outward, examination can be found in the nasal or middle nasal passages with gray-black sputum, with empyema, puncture of the maxillary sinus Sexual secretions and blocky bean dregs-like old blood clots. X-ray examination showed that the shadow of the invaded sinus cavity was deepened, or bone destruction was observed. Mycelia and spores could be found by biopsy.

Disseminated aspergillosis

Aspergillus invades the blood circulation from the lung lesions, and can also invade the wounds through the burn wounds, digestive tract lesions, damaged skin mucosa, and then spread to the heart, lungs, brain, liver, esophagus, stomach, intestines, pancreas, trachea, thyroid, etc. All organs of the body, causing chest pain, cough, hemoptysis or hemoptysis, persistent fever or irregular fever, tachycardia or arrhythmia, irritability, and even coma, sputum, uroscopy and culture can be positive, but blood The culture positive rate is low.

4. Aspergillosis of the skin

Mainly manifested as proliferative granuloma, overlying jaundice, can be squeezed out of the pus, microscopic examination and culture of Aspergillus positive, pathological sections can be found in the tissue Aspergillus.

5. External ear canal aspergillosis

In deafness, Aspergillus causes about 80%, Aspergillus stimulates the external auditory canal to produce inflammatory reactions and scaly, increased sputum, because the tendon is tubular or membranous, can block the ear canal, resulting in hearing loss, conscious symptoms of itching or Fullness of feeling, if there is secondary infection, there is pain, after the sputum is removed, the skin underneath is congested and flushed, and there is erosion and suppuration. The skin of the affected area can be thickened. If the lesion involves the tympanic membrane, the tympanic membrane is congested, such as perforation of the tympanic membrane. Then Aspergillus invades the middle ear to cause otitis media.

6. Aspergillosis

Mainly due to trauma, corneal damage is the most common, the main symptoms are local pain, fear of light, tears and other corneal irritation symptoms, the degree is generally light, examination can be seen ciliary body congestion or mixed congestion, if not treated in time, can cause blindness, Eyelid inflammation, dacryocystitis or choroiditis, and even eye abscesses can also occur, which can be caused by eyeballs and can cause blindness.

Examination of aspergillosis

Direct microscopic examination

Take sputum, sputum, corneal ulcer secretions, pus, etc., for direct smear examination, visible separation of hyphae and round, dark green spores (diameter 2 ~ 3m) or chrysanthemum-like Aspergillus structure, with lactic acid phenol cotton Blue staining is clearer, and the conidiophores are not colored.

2. Fungal culture

The blood and the above specimens were inoculated into the sand castle agar, which can grow quickly at room temperature to 45 ° C. The typical Aspergillus colonies are green to dark green, and the coarse conidial spore stalk can be seen under the microscope. The top end is swollen and there is a small stalk on the stalk. Spores can further identify different strains based on colony morphology and microscopic examination.

3. Chest X-ray film The middle and lower parts of common lungs have scattered flaky, nodular or agglomerated shadows, which can also form voids, sometimes with irregularly distributed fine granular nodular shadows. CT, magnetic resonance examination can find brain occupying lesions.

Diagnosis and identification of aspergillosis

diagnosis

Since Aspergillus is widely present in nature, it is necessary to culture positively multiple times and combine histopathology and clinical symptoms to make a reliable diagnosis.

Mycological examination

2. Imaging examination

The Aspergillus ball has a cavity-like lesion on the chest X-ray, which has a circular or oval shadow. The density is uniform, and there is a crescent-shaped translucent area on the upper side. The X-ray of the Aspergillus sinus ball shows an increase in radiological density. Metal density (calcium phosphating), CT examination showed no adjacent structure invasion.

3. Histopathology

Diagnostic, tissue reactions include non-specific mild inflammation seen in the external auditory canal and bronchial infections, granulomas consisting of epithelioid cells and giant cells common in sinus, eye and lung diseases, and necrosis caused by Aspergillus invasion into blood vessels Alteration, and suppurative changes, PAS or argyrophilic staining Aspergillus is red or black in the tissue, and hyphae can be seen in the abscess and Aspergillus bulb, the branch is at an angle of 45°, and the diameter is 7-10 m. Typically arranged in a radial shape; straight and parallel hyphae can be seen in early granulomas, irregular hyphae are seen in advanced fibrotic lesions, and Aspergillus balls can be found in abscesses or cavities communicating with the air.

4. Skin experiment

The Aspergillus fumigatus antigen skin test contributes to the diagnosis of allergic aspergillosis.

5. The diagnostic criteria for invasive Aspergillus was proposed by the European Society for Cancer Therapy.

(1) The treatment of broad-spectrum antibiotics continued to have fever 38 °C for 3 to 5 days, except for those who confirmed the aspergillosis within 5 days after fever.

(2) Aspergillus blood culture was positive.

(3) Exclusion of viruses, acidophilus, Legionella, Q fever, parrot fever, mycoplasma, chlamydia pneumonia and Pneumocystis infection.

(4) Tips and signs of invasive aspergillosis, such as: lung: cough, difficulty breathing, chest pain, hemoptysis, sputum sound, hypoxia, sinus: headache, increased nasal secretions, facial swelling, tenderness, cellulitis Liver: liver discomfort, jaundice, liver, abnormal liver function, nervous system: headache, facial nerve dysfunction, insanity, altered consciousness, abnormal CSF, other parts: including bone, kidney, skin, pleura, eye, spine , outer ear, endocardium, pericardium, joints, adrenal glands, peritoneum, gastrointestinal tract, lymph nodes and thyroid gland.

(5) Radiologically positive, lung: lung infiltration, non-specific or specific manifestations (nodules, cavities), sinus: mucosal thickening, angiography/sinus shadow, liver, spleen, central nervous system (CNS): Nodules / abscesses (CT, ultrasound and MRI), other parts.

(6) Pathological or cultured Aspergillus-positive at the appropriate site, lung: Bronchial wash / bronchoalveolar lavage / tracheal extract / bronchial biopsy / radiological probe aspirate (FNA) / open lung biopsy, sinus: Nasal / sinus aspirate, biopsy, liver, spleen: FNA / laparotomy / laparoscopic biopsy, CNS: FNA / stereotactic biopsy, cerebrospinal fluid, other parts.

A clear diagnosis should meet the above six points, and isolate the Aspergillus from the affected site. Radiological and clinical features plus positive blood culture can be confirmed by alternative mycological examination.

Differential diagnosis

It should be differentiated from bacterial infections, other fungal infections and tumors. If spherical shadows are found in the lungs, the Aspergillus balls should be differentiated from tuberculosis, benign tumors, and lung abscesses.

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