Necrotizing fasciitis is a purulent inflammation of the fascia and subcutaneous tissue of streptococcal or polymicrobial etiology. Local symptoms include edema, discoloration of the skin, characteristic compaction of the underlying tissues, pain syndrome, which is subsequently replaced by a lack of sensitivity in the affected area. There is a pronounced general intoxication, there is a high probability of sepsis. Necrotizing fasciitis is diagnosed taking into account objective data and laboratory results. Treatment – autopsy, drainage of the abscess on the background of antibiotic therapy.
ICD 10
M72.6
Meaning
Necrotizing fasciitis is a type of necrotic lesion of soft tissues, in which there is necrosis of the superficial fascia, fatty subcutaneous tissue without involving the underlying muscle mass. It is characterized by rapid development, severity of the course, a large number of complications and high mortality. There is information in the literature that the first description of this pathology belongs to the pen of Hippocrates, but most researchers report that the first clinical picture of this disease in 1871 was described in detail by the American surgeon Joseph Jones, calling it “hospital gangrene“. The modern name of the disease has been used since 1952. The incidence in adults is 0.4, in children – 0.08 cases per 100 thousand population. Over the past decade, the prevalence of necrotic fasciitis has increased 5-fold.
Necrotizing fasciitis causes
Necrotizing fasciitis type 1 is caused by polymicrobial associations, type 2 – by monoculture of pyogenic streptococcus. In polymicrobial lesions, a combination of aerobic and anaerobic bacteria is usually found. Enterobacteria and Staphylococcus aureus play the most significant role among aerobes, and bacteroids among anaerobes. Any places of violation of the integrity of the skin can serve as the entrance gate of infection: animal and insect bites, abrasions, abrasions, bedsores, punctures with an injection needle, wounds resulting from injuries or surgical manipulations. The literature describes cases of the disease after laparoscopy, thoracotomy and gastroscopy. Currently, purulent surgeons note an increase in necrosis of the superficial fascia after plastic surgery. Sometimes fasciitis occurs against the background of other purulent processes. Approximately 20% of patients have no visible skin lesions.
The probability of developing necrotizing fasciitis increases in conditions that have a negative impact on the body’s ability to resist the effects of infectious agents, including conditionally pathogenic ones. The list of risk factors includes age over 60 years, diabetes mellitus, exhaustion, malignant neoplasms, injuries, alcoholism, immunosuppressive states, prolonged use of glucocorticoid drugs, obesity, recovery period after injuries and operations, peripheral vascular diseases, subcompensated chronic somatic diseases, intravenous administration of irritating drugs (mainly drugs). Experts point out that the reasons for the increase in morbidity in recent years are an increase in life expectancy, an increase in the number of cases of diabetes mellitus and the appearance of highly virulent strains of pyogenic streptococcus.
Pathogenesis
The leading role in the pathogenesis of necrotizing fasciitis is played by thrombosis of the vessels that nourish the skin, fascia and subcutaneous fat. As a result of the formation of blood clots, there is a violation of perfusion, the amount of oxygen entering the soft tissues sharply decreases, necrosis sites form. Due to the sufficiently deep location of the primary inflammatory focus, pathognomonic clinical manifestations at the initial stages are absent or expressed insignificantly, which causes a delayed diagnosis of pathology. At the same time, necrosis spreads along the fascial case with great speed: according to the observations of specialists, about 2.5 cm of the fascia undergoes necrosis within one hour. The underlying muscles are not involved in the process.
Necrotizing fasciitis symptoms
The topography of the pathological process is characterized by significant variability. It is possible to damage any area of the body, but most often necrotic changes are detected in the extremities, anterior abdominal wall, buttocks and genitals. The beginning is sudden. The first symptom is increasing pain in the affected area. There is an increasing swelling of soft tissues. A focus of indistinctly expressed erythema is formed, in the area of which a hemorrhagic rash subsequently appears, bulls with serous or hemorrhagic contents are formed, replaced by areas of necrosis.
At first, palpation of the affected area is painful, subsequently, due to the death of nerve endings, sensitivity is lost. When feeling, the woody density of the fabric is determined. Crepitation is often detected due to the accumulation of gas bubbles. Fluctuation is atypical, usually detected only with the development of necrotizing fasciitis against the background of purulent-inflammatory process. The area of lesion of the underlying tissues significantly exceeds the size of the focus of skin changes. Regional lymphangitis and lymphangiitis are absent.
There is a general hyperthermia up to 39-40 degrees Celsius or more. Significant daily fluctuations in body temperature are characteristic. Intoxication syndrome includes general weakness, severe headache, insomnia, lethargy, lack of appetite, nausea, vomiting. There is tachycardia, hypotension, increased breathing, hematuria, oliguria, severe dehydration, intestinal paresis. There is a possibility of the formation of acute ulcers of the stomach and intestines with subsequent bleeding.
A separate form of necrotizing fasciitis is Fourier gangrene, localized in the genital area and affecting mainly men (98% of the total number of patients with this type of pathology). Symptoms appear against the background of diseases of the genitals (cracks, phimosis, paraphimosis) and general processes (for example, severe diabetes mellitus) or occur without previous changes. The scrotum swells, becomes painful, hyperemic. A black necrosis zone forms on the skin, rapidly spreading to the perineum, anterior abdominal wall and the hip area. Otherwise, Fourier gangrene proceeds with the same symptoms as necrotic fasciitis of other localizations.
Complications
Complications include rapidly developing sepsis and septicemia with the occurrence of infectious and toxic shock, gross violations of water-salt and acid-base balance, multiple organ failure. Even with the timely start of treatment, there is a risk of death. In the postoperative period, decompensation of existing chronic diseases, the development of intercurrent infections, thrombosis, congestive pneumonia and other complications associated with a general serious condition, a sharp weakening of the body, a violation of the activity of all organs and systems is possible.
Diagnostics
Due to the non-specificity of the data obtained, difficulties in conducting or the duration of preparation of the results of most additional studies, the main role in the diagnosis is played by characteristic clinical symptoms. Pathognomonic manifestations of necrotizing fasciitis are the rapid transformation of the erythema focus into blisters or necrosis zones, woody density of the underlying tissues both in the area of skin changes and beyond, crepitation and intense pain syndrome, followed by skin anesthesia. The survey program includes the following additional methods:
- Visualization methods. Radiography in the early stages is unchanged, subsequently free gas is visible in the images. CT and MRI indicate the presence of free gas and uneven thickening of the fascia, allow you to clarify the boundaries of the affected area.
- Laboratory tests. In the general blood test, leukocytosis, thrombocytopenia, and a decrease in hemoglobin levels are detected. The biochemical analysis of blood determines hypoproteinemia, hypoalbuminemia, hypocalcemia, hyponatremia, increased levels of urea, creatinine, uric acid, a large amount of C-reactive protein.
- Histological and microbiological studies. Necrotic changes of adipose tissue and fascia, signs of vasculitis, local hemorrhages are detected in the tissue sample. When sowing on nutrient media, the growth of streptococci is usually observed. It is possible to detect bacteroids, enterobacteria and some other microorganisms as part of microbial associations.
Differential diagnosis is carried out with other infectious processes affecting soft tissues. Cellulite and indurative erythema are characterized by the absence of systemic toxicity, intense pain syndrome and tissue necrosis. With anamnesis of indurative erythema, tuberculosis is often detected in patients. With clostridial myonecrosis, foci of necrosis also occur in soft tissues, but the muscles are affected, not the fascia. Differentiation of myonecrosis and fasciitis is performed on the basis of the results of microbiological examination and data obtained during surgery. With toxic shock syndrome of a different etiology, there are no symptoms pathognomonic for necrotic fascia lesion.
Necrotizing fasciitis treatment
The treatment of the disease is carried out by specialists in the field of purulent surgery. If symptoms of this pathology are detected, emergency hospitalization in a hospital with the possibility of resuscitation is indicated. Infusion therapy begins at the stage of transportation. Water-salt solutions are transfused, hormonal drugs are injected. In case of respiratory disorders, urgent intubation of the trachea with artificial respiration support is required. The treatment plan includes:
- Surgical intervention. According to vital indications, necrectomy is performed as soon as possible after the patient is delivered to the surgical department. Necrotized areas are excised to unchanged tissues, the wound is left open. A second revision is performed during the day. With the progression of the pathological process, amputation may be required.
- Antibiotic therapy. The introduction of antibacterial agents begins from the moment of admission. First, broad-spectrum antibiotics are used, after determining the sensitivity of pathogens, prescriptions are corrected.
- Systemic therapy. During the operation and stay in the department, infusion therapy is continued to correct the acid-base and water-salt balance. Vitamins and trace elements are prescribed. To stimulate immunity, donor plasma is injected. Hyperbaric oxygenation is performed to accelerate wound healing, neutralize endotoxins, and eliminate tissue hypoxia.
Prognosis and prevention
The prognosis for necrotizing fasciitis is always serious. According to various data, from 20 to 47% of cases end in the death of the patient. In other cases, disorders from various organs may be observed in the outcome, due to sepsis and acute polygonal insufficiency during the illness. After removal of necrosis foci, extensive wound surfaces are formed, requiring closure by plastic surgery. Possible scarring with the appearance of gross cosmetic defects, limitation of limb function. Prevention includes measures to prevent immune disorders, exclude or minimize other risk factors. If necrotizing fasciitis is suspected, urgent transportation to a surgical hospital and urgent medical measures are required immediately upon admission.
Literature
- Kim YH, Ha JH, Kim JT, Kim SW. Managing necrotising fasciitis to reduce mortality and increase limb salvage. J Wound Care. 2018 Sep 01;27(Sup9a):S20-S27. – link
- Lange JH, Cegolon L. Comment on: Early clinical manifestations of vibrio necrotising fasciitis. Singapore Med J. 2018 Aug;59(8):449. link
- Heijkoop B, Parker N, Spernat D. Fournier’s gangrene: not as lethal as previously thought? A case series. ANZ J Surg. 2019 Apr;89(4):350-352. – link
- Erichsen Andersson A, Egerod I, Knudsen VE, Fagerdahl AM. Signs, symptoms and diagnosis of necrotizing fasciitis experienced by survivors and family: a qualitative Nordic multi-center study. BMC Infect Dis. 2018 Aug 28;18(1):429. link
- Khalid M, Junejo S, Mir F. Invasive Community Acquired Methicillin-Resistant Staphylococcal Aureus (CA-MRSA) Infections in Children. J Coll Physicians Surg Pak. 2018 Sep;28(9):S174-S177. – link