Caseous necrosis of the lung

Caseous necrosis (from the Latin. caseosus - “cheesy” and other Greek. νέκρωσις - “death”) - description of the form of death of biological tissues, a type of coagulative necrosis, separated into a special group because of its appearance. Dead tissue looks like a soft, white proteinish, cheesy consistency necrotic mass.

Appearance

Often, caseous necrosis is associated with tuberculosis. It can also be caused by syphilis or certain fungi: usually the appearance can be associated with histoplasmosis, cryptococcosis and coccidioidomycosis.

Appearance

When caseous necrosis does not preserve the histological architecture. When examined under a microscope with hematoxylin and eosin staining, it is characterized with pink cells of necrosis devoid of cells, surrounded by a granulomatous inflammatory process.

When the basal lymph node, for example, is infected with tuberculosis, and everything goes to caseous necrosis, the skin color from cheese yellowish-brown to white may begin to manifest itself en masse, which is why this type of necrosis is often depicted as a combination of both types of coagulation and collimation necrosis. .

However, in the lungs, caseous necrosis with a granular yellowish-brown shade of the surface is more common. Tissue destruction is so extensive that there are a number of areas with voids (also known as cystic spaces).

Caseous pneumonia: diagnosis and treatment


For pneumonia caused by tuberculosis, urgent hospitalization of the patient is necessary.

The rapid increase in the incidence of socially significant diseases, as well as the deterioration of the sanitary and epidemiological situation in the world, is causing an increase in the number of acute and rapid forms of tuberculosis. Caseous pneumonia is a specific form of pulmonary mycobacterium tuberculosis, accompanied by the formation of a large number of cavities of pulmonary decay.

What causes its development, what symptoms does it have, how is it diagnosed and treated: let's look at our review and video in this article.

Epidemiology

According to statistics, in recent years, the incidence of caseous pneumonia has increased slightly: on average, it is 3-5% of all cases of newly diagnosed tuberculosis.

The risk of developing this pathology in adults of representatives of medical and social risk groups increases:

  • persons with acquired and congenital forms of immunodeficiency (including HIV),
  • alcohol abusers and drug addicts
  • persons who have been undernourished for a long time,
  • persons undergoing treatment with immunosuppressants, cytostatics, glucocorticosteroids.

Reduced immunity increases the possibility of developing the disease

Important! One of the main factors that increase the risk of pneumonia with caseous necrosis is considered to be infection with virulent mycobacteria that are resistant to first-line anti-TB drugs.

Causes and mechanism of development

The caseous form of pneumonia refers to specific infectious processes. This means that a single pathogen causes the disease, in this case Mycobacterium tuberculosis.

. The actinobacteria Mycobacterium tuberculosis was discovered on March 24, 1882 by the German microbiologist Robert Koch. Later, the causative agent of tuberculosis is called Koch's wand, and on May 24 it was declared the World Day to combat this socially significant disease.

In the pathogenesis of the development of the disease, two things matter:

  • reduced body resistance, weakened immunity,
  • exposure to a large number of highly virulent pathogens.

Most often caseous pneumonia complicates the course:

  • fibro-cavernous tuberculosis,
  • disseminated tuberculosis (including miliary),
  • infiltrative tuberculosis.

More often develops lesions of the upper lobe of the lung

Note! Usually, the “primary source” of the infection cannot be identified, and tuberculous pneumonia is diagnosed as the primary disease.

Pathological changes of the lung are complex and diverse. First of all, they are described by a cheesy necrosis (caseous disease), which develops very quickly and leads to the complete destruction of the pulmonary parenchyma. The outcome of the disease is the formation of a “destroyed lung”.

Cheesy necrosis (pictured) is accompanied by widespread destruction.

Classification

Depending on the prevalence of pathological changes, the following types of caseous pneumonia are distinguished:

  1. Acinous (affected acinus of the lung). It is characterized by a small lesion area, unexpressed clinical symptoms.
  2. Lobular (several lobules are affected). Differs in the presence of several large caseous foci. It is characterized by a rapid course with signs of severe intoxication and initial manifestations of respiratory failure.
  3. Lobar (tuberculous inflammation of the whole lobe of the lung). In this form of the disease, there is a widespread caseous destruction. In addition to areas of necrosis, pathology is accompanied by purulent fusion.

The more common a tuberculous lesion, the brighter the clinical picture

Clinical manifestations

Pneumonia caused by Koch sticks has symptoms similar to other forms of tuberculosis. However, unlike them, the disease is characterized by a sudden acute onset and violent clinical manifestations. Common signs are presented in the table below.

Table 1: Patient complaints:

SymptomNumber of patients
93,8%
90,6%
Increase in body temperature to 38-38,5 ° С87,5%
87,5%
83,9%
74,0%
Insomnia and other sleep disorders56,3%
51,8%

Important! In the first 7-14 days from the onset of the disease, the cough is dry and unproductive. Then a significant amount of sputum, sometimes colored brownish, begins to be produced.

Often the disease mimics other pathologies. Differentiate this form of tuberculosis with:

  • flu and other acute respiratory viral infections,
  • non-specific pneumonia,
  • sepsis.

Basics of diagnosis

Diagnosis of caseous pneumonia is quite complicated. The physician must take into account not only the clinical manifestations of the disease, but also laboratory and instrumental indicators.

Standard Instruction involves the appointment of the following diagnostic tests:

  • Clinical:
    1. collection of complaints and anamnesis
    2. general examination (pallor, blush on cheeks, acrocyanosis, signs of weight loss),
    3. NPV measurement (tachypnea, dyspnea),
    4. measurement of heart rate (tachycardia), blood pressure (usually hypotension),
    5. pulmonation and lung percussion (the presence of areas of weakening of breathing and dull clear lung sound).
  • Laboratory:
    1. OAK (leukocytosis combined with lymphopenia, accelerated ESR up to 50-60 mm / h)
    2. OAM (normal or non-specific changes),
    3. sputum smear microscopy - (detection of a large number of acid-resistant MBT).
  • Instrumental:
    1. x-ray lung (intensive darkening of one or both lungs, combined with areas of enlightenment, areas of bronchogenic elimination),
    2. CT, MRI - is carried out to confirm the diagnosis.

Current approaches to therapy

Treatment of caseous pneumonia is a long and difficult process. It consists of four main components:

  1. Specific anti-tuberculosis chemotherapy - aimed at the destruction of the mycobacterial population.
  2. Antimicrobial therapy - designed to suppress nonspecific opportunistic pulmonary microflora.
  3. Detoxification, pathogenetic therapy - is carried out with the aim of eliminating the pathological processes developing in the lungs, stimulating reparative processes.
  4. Surgical treatment - aimed at the removal of destructive pulmonary tissue.

Despite the fact that the price of the combined course costs thousands of dollars, in Russia the treatment of tuberculosis is free

The general principles of treatment of caseous pneumonia are as follows:

  • compulsory hospitalization of a patient in a tuberculosis hospital,
  • bed rest with pronounced signs of intoxication,
  • the expansion of the regime with the improvement of the state, breathing exercises and physical therapy,
  • detoxification measures based on infusion of hemodez, saline, reopolyglukine,
  • compulsory planned or emergency surgical treatment.

During surgery, the affected lung tissue is removed.

Note! Since tuberculous pneumonia is diagnosed at advanced stages, surgical methods of therapy are associated with a high risk of death. In this case, in the majority of patients, the operation remains the only chance of saving life.

An important result of the combined anti-tuberculosis therapy remains the rapid cessation of bacteria excretion - after 2-3 months, patients are not dangerous to others. Against the background of adequate treatment, signs of intoxication disappear in 1-4 months.

Dynamic observation of patients allows us to estimate the rate of regression of the caseous necrotic processes and the formation of pneumosclerosis.

Caseous pneumonia in tuberculosis: causes, symptoms, treatment

Tuberculosis, if it turns into an open form, then most often it proceeds quite hard. One of the serious complications of the disease is caseous pneumonia. The disease can develop independently, but more often against the background of other forms of tuberculosis. What is this pathology, how to deal with it?

What it is?

Caseous pneumonia in tuberculosis is a form of pathology in which inflammation occurs in the lung tissue with the formation of a cheesy necrotic area. Pathological changes affect most of the lungs, sometimes a whole fraction or more.

Caseous tuberculosis has two forms:

  • Share Usually develops as an independent disease.
  • Lobular or lobular. It is a secondary infection that develops at the end of infiltrative tuberculosis.

The disease has a rapid course. Develops with the change of stages:

  1. At the first, an inflammatory process develops with the involvement of blood vessels and lymph nodes. In the lung tubercle is formed, the cells disintegrate with caseous necrosis.
  2. At the next stage, there are already irreversible changes: the granulomas melt, forming a cheesy mass characteristic of the disease. Dying foci spread to neighboring tissues, merging caseous areas are formed.

The disease is registered in tuberculosis in a small number of patients, but it leads to irreversible and severe consequences.

Main reasons

Caseous pneumonia develops under one condition - mycobacterium enters the human body. But there is one nuance that not all tubercle bacilli can provoke pathology, but only those that are highly virulent and sufficiently resistant to anti-tuberculosis drugs.

Even the presence of mycobacteria in the body does not guarantee that the pathology will begin to develop. There must be good reasons for this to happen. The most important of them is a reduced immunity, in which the immune system is not able to resist the onslaught of bacteria.

Who is at risk?

The risk categories for the development of caseous tuberculosis include the following categories of citizens:

  • Outgoing sentence in prison.
  • Medical workers of tuberculosis institutions.
  • Disabled people who are in close proximity to a patient with tuberculosis.
  • HIV-infected.
  • Elderly patients.
  • Having a diagnosis of type 1 or 2 diabetes.
  • Leading an immoral lifestyle.

Formed immunodeficiency is a provoking factor in the development of pathology. And it can develop on the background:

  • Prolonged stress.
  • Poor nutrition or fasting.
  • Lack or deficiency of vitamins and minerals.
  • Chronic infectious pathologies.
  • Hereditary predisposition.
  • Therapy with hormones and glucocorticosteroids.
  • In the presence of cancer.

The combination of several factors increases the likelihood of developing a serious disease when a tubercle bacillus enters the body.

Symptoms and signs

Pathology is distinguished by its symptomatology, because in one case it may resemble ordinary pneumonia, and in another it may resemble flu-like symptoms with body aches. There are cases when caseous pneumonia develops according to the type of sepsis with signs of intoxication.

The disease manifests itself suddenly and with acute symptoms.

Symptoms vary depending on the stage of the pathology:

  1. The initial stage is characterized by the following manifestations: chills, loss of appetite, general weakness, excessive sweating.
  2. At the next stage of development, a dry cough appears, a little sputum, but it is difficult to leave, there may be blood clots. In the lungs at this stage, decay cavities are formed.
  3. Further, the symptoms are aggravated: hemoptysis is observed as a result of pulmonary hemorrhage, the skin is pale with a yellowish tinge. The condition is characterized as severe.
  4. At the last stage of development, the sputum is coughed up with an admixture of pus, a heart rhythm disorder is observed, and hypoxia is present.

When listening to the patient's breathing is weak, moist fine wheezing is heard.

The main syndromes of the disease include:

  • Intoxication. Manifested by pallor of the skin, there is a nervous overexcitement or apathy. Often vomiting and fever.
  • Catarrhal syndrome. Against the background of the destruction of the epithelium observed cough.
  • Damage to the lungs leads to wheezing, shortness of breath and high fever.
  • Syndrome hematological changes. Laboratory tests show abnormalities.

Patients with caseous pneumonia have mental disorders. Appear hallucinations, nonsense.

Diagnostics

For an accurate diagnosis, it is important to analyze the full picture of the disease, to study the patient's history. According to one symptom it is impossible to draw conclusions, it is necessary to use various diagnostic methods:

  1. With the development of pathology on the background of tuberculosis, the Mantoux test does not give a positive result.
  2. In the sputum, bacteriological examination revealed pathogens of the disease.
  3. Radiographs show changes in lung tissue.

To clarify the diagnosis, it is important to differentiate caseous pneumonia from lung infarction, purulent inflammatory processes, as well as croupous pneumonia.

Therapy of this form of pneumonia is carried out only in the hospital. It includes the following steps:

  • Chemotherapy.
  • Acceptance of antibacterial drugs.
  • Detoxification therapy.
  • Surgical intervention.

It is important to start treatment as soon as possible in order to stop toxic shock and to prevent irreversible consequences.

Medicamentous

This therapy is intended for the early suppression of the activity of mycobacteria. Given the high resistance of Koch sticks to antibacterial drugs, the doctor prescribes them in combination. As a rule, these are the following medications:

In the absence of the effect of prescribed: "Ethambutol", "Ofloxacin", "Kanamycin". The treatment regimen is prescribed only by a doctor, and the duration can be from 3 months or more.

In addition to chemotherapy drugs, the patient is prescribed:

  • Antibiotics from the group of cephalosporins and macrolides.
  • Detoxification therapy by administration of glucose, saline, metabolites.
  • Medications for liquefying and removing sputum.
  • Inhalation through the nebulizer with drugs to affect the obstruction of the bronchi: "Salbutamol" with "Fliksotidom", "Berotek."
  • Receiving drugs for fever and painkillers.
  • Be sure to vitamin preparations.
  • Immunomodulators.

It is also recommended to conduct bronchoscopy with sputum suction and the introduction of antiseptic agents.

Surgical

Surgical intervention is carried out in order to remove the damaged part of the lung. This method of therapy is considered to be quite effective, but doctors approach it with caution. Depending on the patient's condition, there is a high risk of death in the postoperative period.

There are two types of operations:

  1. Pulmonectomy - removal of the whole organ. Conducted with a strong lesion of the lung.
  2. Resection. The surgeon excises only the affected part of the organ.

Abdominal surgery is required to remove the whole lung, and excision is possible using minimally invasive interventions:

  • Using a laser.
  • Electro knife.
  • By freezing.

In all cases, thorascopy is carried out through small sizes.

Disease therapy is a long and complicated process. If after a few months it turns out to be improved by effective and complex therapy, all the same, only an excision of a severely affected area is a chance for salvation, and not everyone can withstand surgery and recovery after it.

According to statistics, only 20-25% of all patients have a chance for a full recovery, and then provided that the pathology is detected in the early stages of development.

Complications and consequences

Caseous pneumonia almost never passes without a trace for the body. Mycobacteria destroy lung tissue, which leads to disruption not only in the respiratory system, but also in other organs. Complications may be as follows:

  • Liver dysfunction.
  • The appearance of failures in the nervous system.
  • Insufficiency of adrenal cortex develops.
  • Dystrophy of the heart muscle.
  • Septic arthritis.
  • Lung collapse.

In severe cases, it can all be fatal.

Prevention

Preventive measures will help to avoid serious illness. These include:

  • Maintain a healthy lifestyle.
  • The elimination of bad habits.
  • Balanced diet.
  • Maintain immunity.
  • Exclusion of communication with patients with tuberculosis and suspicious individuals.

To prevent the development of complications is quite possible for everyone, if you visit a doctor in a timely manner when suspicious symptoms appear. Caseous pneumonia among the pathologies of the pulmonary system has a high mortality rate, only paying great attention to your health and the state of the immune system can avoid it.

Causes and pathogenesis of the disease

The causative agent of caseous pneumonia is pathogenic bacteria of the genus Mycobacterium. Infection is carried out by airborne. The source of infection is patients with tuberculosis, which release bacteria into the environment with exhaled air.

Aspiration of blood and penetration of the pathogen into the organs of the respiratory system. The probability of infection increases with immunodeficiency, weakness of immune protection. HIV-infected patients, alcohol and drug addicts are at risk.

Photo 2. The spread of tubercle bacilli in the body with blood.

Against the background of an insufficient immune response, there is an intensive reproduction of mycobacteria in the tissues of the lung. Identify atypical forms of protective cells - phagocytes and lymphocytes.

These cells are unable to maintain the growth of bacterial colonies, they are prone to apoptosis - programmed death.

Accelerated multiplication of bacteria causes damage to the cell membranes and aggravates immunodeficiency.

The development of caseous pneumonia occurs in several stages. Formed primary complex (inflammation of the lung tissue, blood vessels and regional lymph nodes). In the lung parenchyma a nodule is formed, a tubercle, which then transforms. At the initial stage of caseous pneumonia of the lungs, local inflammation, disintegration of cellular elements and the development of caseous necrosis in tuberculosis are noted.

Photo 3. Caverns in lung tissue.

The disease progresses rapidly and proceeds to the next, irreversible, stage. Focal necrosis of a rounded formation occurs, granulomas are melted, characteristic cheesy masses appear. Necrotic changes spread to the surrounding tissues, caseous foci and foci form around the initial zone, which then merge.

Mycobacteria can penetrate the lumen of the bronchi and blood vessels, spread throughout the lobe of the lung. There is a risk of the spread of the pathogen with the flow of lymph or blood to other organs.

Characteristic morphological changes are inflammation of the lung parenchyma, filling of the alveoli and bronchioles with cheesy necrotic masses.

Partitions between the alveoli preserve their structure first, but then also undergo necrosis.

When the resulting caseous masses melt, pathological cavities or cavities are formed. Disintegration of lung tissue may be accompanied by sequestration. A sequestrum is a portion of dead tissue that does not undergo autolysis (melting) and is separated from the intact parenchyma.

An unfavorable prognosis exists when late diagnosis and early treatment. The main cause of death in caseous tuberculosis is pulmonary heart disease. Pathology develops on the background of inflammation of the lung parenchyma, necrotic changes, severe intoxication with tissue breakdown products.

Photo 4. Pulmonary heart disease is a fatal complication of caseous pneumonia.

Symptoms of caseous pneumonia

The disease is characterized by a sudden onset and rapid progression. At the initial stage, intoxication phenomena come to the fore: pallor, weakness, chills.

Photo 5. Intoxication syndrome accompanies the development of tuberculosis.

A typical clinical form at the onset of caseous tuberculosis consists of the following phenomena:

  • Increase in body temperature to 38-39? С
  • dyspnea,
  • dry cough, sometimes mixed with sputum,
  • dyspepsia, weight loss.

The disease progresses rapidly, necrotic processes develop in the lungs.

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Additional symptoms appear in the following stages:

  • Pain in the chest,
  • symptoms of bronchopneumonia,
  • fever,
  • labored breathing,
  • wet cough, with sputum,
  • signs of hemoptysis.

The clinical signs of caseous pneumonia, which develops as a complication of another form, depend on the particular course of the primary pathology.

Photo 6. A wet cough signals the progression of the disease.

In any form, the features will be necrotic changes followed by melting or sequestration. Impurities of blood during coughing appear when vascular damage occurs after pulmonary hemorrhage.

Clinical signsBlood testsELISASputum testMantoux test resultX-ray examinations
  • Acute onset of the disease, palpable, but not constant pain in the chest, body temperature is elevated, daily variations in the range of 1-3 ° C are possible
  • Increased and persistent sweating.
  • The scarcity of percussion and auscultatory changes, mucopurulent sputum is observed in the lungs
  • Pronounced neutrophilic leukocytosis
  • Lymphopenia, leukocyte shift, monocytosis possible
  • Toxic neutrophil granularity
  • ESR more than 40 mm / h
Neg.In the first weeks of the disease, MBT may not be detected in the sputum under study, but in later periods, there is MBT in the sputum. Flora is more often gram-negative than gram-positive.Neg.
  • Bilateral and upper lobe localization
  • Heterogeneity of infiltration, there may be areas of enlightenment
  • The presence of foci of the disease on the periphery of the infiltrate, as well as in another lung

The table shows the main signs of caseous pneumonia.

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Causes of caseous pneumonia

The causative agent of the infectious disease is Mycobacterium tuberculosis (Koch bacillus).

Caseous pneumonia is formed when a person is massively infected with highly virulent, often resistant to tuberculostatic agents, or when a persistent tuberculosis infection persists in the body.

Most often, caseous necrosis of the lung tissue is complicated by the course of disseminated or fibrous-cavernous tuberculous process. A necessary condition for the occurrence of the disease is pronounced immunosuppression. At risk for the development of severe tuberculosis infections include:

  • Socially maladjusted individuals. Includes homeless persons engaged in vagrancy, refugees. Pronounced secondary immunodeficiency is often observed in patients with alcohol dependence, drug addiction. There is a high probability of infection with drug-resistant tuberculosis and the occurrence of its severe forms in people serving sentences in prisons.
  • Medical risk group. Most often caseous pneumonia is detected and becomes the cause of death in AIDS patients who do not take antiviral drugs and specific chemoprophylaxis drugs. There is a high risk of this pathology in patients receiving long-term corticosteroids and cytotoxic drugs with diabetes.

The disease is formed against the background of the deficiency of immune cells that are active against infection. Mycobacteria multiply freely, releasing a number of toxic substances. The waste products of microorganisms damage the membrane of immune cells. A vicious circle is formed - immune disorders are aggravated, tuberculosis progresses, even more depressing the immune system.

Initially, the pathological process is localized within one segment. Microcirculation is disturbed in the affected area. Blood clots form in the vessels supplying the lung tissue. Lack of adequate blood supply causes massive cell death - caseous necrosis.

By the bronchogenic and lymphohematogenous pathways, mycobacteria enter the adjacent segments, the opposite of the lung, can be carried into other organs and tissues. Within 2–3 weeks, common tubercular pneumonia develops.

Pathological examination reveals an extensive, often bilateral lesion of the lungs with characteristic irregularly shaped decay cavities, partially filled with caseous masses. The parietal and visceral pleura is involved in the process. Caseous pleural overlays are formed.

Treatment of caseous pneumonia

After diagnosis, the disease is treated by a TB doctor. Etiotropic therapy with tuberculostatic drugs is prescribed taking into account the resistance of mycobacteria to drugs. The treatment is two-step.

The intensive phase of chemotherapy is carried out in a specialized hospital. Detoxification agents, antihypoxants, immunostimulants, corticosteroid hormones are used. Nutrition of the patient should be balanced, high-calorie.

In the presence of multiple or giant single cavities of destruction, the question of surgical intervention is considered. In the absence of contraindications performed resection of the lung.

Treatment with anti-tuberculosis drugs in the continuation phase is performed for a long time (up to 24 months) on an outpatient basis under the supervision of medical professionals.

Prognosis and prevention

The prognosis for pneumonia of a specific nature is always serious. The disease regresses with the formation of dense foci in approximately 25% of cases. This healing process is the outcome of acinar or lobular inflammation.

Caseous lobites are transformed into chronic fibro-cavernous or cirrhotic pulmonary tuberculosis. The long course of tuberculosis infection gradually leads to the formation of a pulmonary heart, the occurrence of amyloidosis and the disability of the patient.

Specific prevention of severe forms of tuberculosis is carried out by vaccinating children with BCG vaccine within a decree period.

Non-specific measures include adherence to a healthy lifestyle, good nutrition, timely preventive X-ray fluorography examinations. HIV-infected patients are given preventive treatment with tuberculostatics.

Watch the video: Histopathology Lung --Tuberculosis (January 2020).