Intestinal candidiasis is an infectious lesion of the digestive tract caused by the patient’s own fungal flora (Candida spp.) against the background of a significant weakening of immunity. Clinical manifestations of intestinal candidiasis vary depending on the form of the disease: dilution of stool, increased flatulence, unspecified abdominal pain, ulcerative colitis and fungal sepsis. The diagnosis is made on the basis of endoscopic examination, histological and cultural analysis of biopsies, feces. Treatment includes three main directions: the appointment of antimycotics, normalization of intestinal microflora and correction of the patient’s immune status.
Intestinal candidiasis is a fungal lesion of the mucous membrane of the digestive tract. It is an urgent problem of our time, since the diagnosis and determination of criteria for this disease are difficult for many clinicians. This is due to the ubiquity of Candida fungi, including in the body of healthy people (the carriage of Candida fungi in the intestines is inherent in 80% of the population). Invasive intestinal candidiasis is almost never found in people with a normally functioning immune system, it is almost always an opportunistic infection associated with an immune imbalance of the body.
In addition, it can be quite difficult for many specialists to differentiate between transient candidiasis and non-invasive intestinal candidiasis (it is he who makes up the vast majority of all clinical cases of candidiasis of the digestive system). It is possible to distinguish between these two states only with the availability of modern diagnostic equipment. To establish a correct diagnosis, it is necessary to have three diagnostic criteria: the identification of one or more risk factors, endoscopic signs of intestinal candidiasis, a positive result of a cultural study. Thus, the tactics of prescribing antimycotics at the first detection of Candida fungi in crops, without further examination, is erroneous.
Causes of intestinal candidiasis
Specialists in the field of gastroenterology distinguish two pathogenetic forms – invasive and non-invasive. In clinical practice, non-invasive form is more common against the background of dysbiosis and mixed intestinal infection (fungal-bacterial, fungal-protozoal, etc.). The visceral form develops against the background of pronounced neutropenia (almost complete absence of neutrophil leukocytes) and late stages of AIDS.
For the formation of intestinal candidiasis, the presence of at least one of the predisposing factors is necessary:
- physiological decrease in immunity (newborn period or old age, severe stress, pregnancy);
- congenital immunodeficiency (Di George, Nezelof syndrome, etc.);
- oncopathology, especially during polychemotherapy;
- autoimmune and allergic diseases (exacerbates the suppression of immunity treatment with corticosteroid hormones);
- taking immunosuppressants after organ transplantation;
- severe endocrine diseases, somatic pathology requiring intensive therapy;
- long-term treatment with reserve-line antibacterial drugs;
- primary immunodeficiency syndrome;
- a pronounced imbalance of nutrients in the diet (especially a lack of protein and vitamins).
In clinical practice, intestinal candidiasis is more common due to a combination of several of these factors.
With a non-invasive form, Candida fungi begin to multiply uncontrollably in the lumen of the intestine, without penetrating into the thickness of its mucosa. At the same time, specific fungal toxins are released, poisonous fermentation products are formed, which have an irritating effect on the intestinal mucosa. The listed toxic agents provoke further aggravation of dysbiosis, the formation of mycotic allergy, secondary immunodeficiency.
The pathogenesis of invasive intestinal candidiasis is different. Provided that local and general immunity is weakened, Candida fungi are intimately attached to the intestinal epithelium (they have a tropicity to a flat multilayered epithelium), then they are embedded in its thickness, transforming into a filamentous form. In the presence of pronounced suppression of cellular immunity, Candida penetrate into the bloodstream and spread throughout the body, causing visceral candidiasis (liver, pancreas).
Symptoms of intestinal candidiasis
Intestinal candidiasis occurs in three main clinical forms: invasive diffuse, invasive focal and non-invasive. The criteria for the diagnosis of invasive diffuse intestinal candidiasis are the patient’s serious condition against the background of severe intoxication, fever, severe abdominal pain, diarrhea, blood admixture in the stool, systemic manifestations of mycosis (liver, pancreas, spleen, gallbladder, etc.). If this form of intestinal candidiasis is an accidental finding during an examination for other diseases, first of all you should think about the debut of AIDS or diabetes mellitus. Invasive diffuse intestinal candidiasis is not typical for people with a normally functioning immune system.
Invasive focal intestinal candidiasis can complicate the course of duodenal ulcer, ulcerative colitis. This form of candidiasis can be suspected in patients with a persistent and prolonged course of background disease that does not respond to standard therapy. This variant of mycosis is characterized by local invasion of the filamentous Candida form in places of impaired epithelialization (at the bottom of intestinal ulcers). At the same time, fungal druses are not detected in the surrounding tissues, other parts of the intestine. The clinical picture corresponds to the underlying disease, and pseudomycelia is detected accidentally during histological examination of biopsies.
Non-invasive intestinal candidiasis is the most common form of this disease. This pathology is not associated with the penetration of fungi into the thickness of the intestinal wall, but is associated with massive reproduction of Candida in the lumen of the intestine. At the same time, a huge amount of toxic metabolites is released, which have both local and general resorptive effects. Today, it has been established that non-invasive candidiasis accounts for about a third of all cases of intestinal dysbiosis. Clinically noninvasive intestinal candidiasis occurs against the background of a satisfactory patient’s condition, accompanied by moderate intoxication, abdominal discomfort, flatulence, unstable stool. Often in such patients, various allergic diseases worsen. This form of candidiasis is often confused with irritable bowel syndrome.
The diagnosis of intestinal candidiasis is complicated by the lack of typical clinical signs, as well as sufficiently specific and sensitive methods for detecting Candida fungi in tissue samples and feces. In the general analysis of blood in severe forms of the disease, a decrease in the number of leukocytes, lymphocytes, erythrocytes is determined. It is mandatory to consult an endoscopist to choose the optimal method of intestinal examination. During endoscopy, non-specific signs of mucosal lesions are usually detected, therefore, endoscopic biopsy and morphological examination of biopsies are crucial in making a diagnosis.
The difficulties of diagnosis lie in the fact that pseudomycelia of fungi can not be detected in all samples of the material, so false negative results are quite common. Visually, with diffuse invasive intestinal candidiasis, signs of ulcerative-necrotic mucosal lesions are determined, and with non–invasive – catarrhal inflammation. The diagnostic criterion for invasive intestinal candidiasis is the presence of candidiasis pseudomycelia in biopsies and prints of the intestinal mucosa.
All patients with a fungal intestinal lesion must undergo a stool analysis for dysbiosis, bacteriological examination of feces. Most often, these tests reveal a mixed flora: not only Candida fungi, but also E. coli, Klebsiella, staphylococci, etc. The detection of more than 1000 colony-forming units per gram of pathological material indicates in favor of intestinal candidiasis and excludes the carrier of fungal flora. The main objective of cultural research is to establish the type of pathogen, to determine the sensitivity of the isolated microflora to antimycotics.
Treatment of intestinal candidiasis
Consultation of a gastroenterologist with intestinal candidiasis allows you to identify risk factors for this disease, determine the amount of necessary research. Since intestinal candidiasis has no specific clinical signs, it can be quite difficult to suspect this pathology. In the presence of laboratory evidence of intestinal candidiasis, the choice of treatment tactics depends on the clinical variant, the presence of concomitant pathology, and the tolerability of antimycotic drugs. Mandatory links in the treatment process for intestinal candidiasis are: correction of a background disease that led to a decrease in immunity and activation of fungal flora; appointment of a targeted antifungal agent; modulation of immunity.
Patients with diffuse invasive form of intestinal candidiasis are hospitalized. The drugs of choice for invasive mycoses are azole antimycotics (ketoconazole, fluconazole, itraconazole, etc.), which are actively absorbed from the intestine and have a systemic effect. Treatment usually begins with the introduction of amphotericin B, then they switch to therapy with fluconazole.
For the eradication of fungal flora in non–invasive forms of intestinal candidiasis, antifungal drugs of nonresorptive action are used – they are poorly absorbed by the intestinal mucosa and have a strong local effect. Nonresorptive polyene antimycotics have a number of advantages – they have practically no side effects, they do not inhibit the normal intestinal microflora, they do not cause addiction. Polyene drugs include natamycin, nystatin. Since the state of dysbiosis and mixed flora are important in the pathogenesis of non-invasive candidiasis, antimicrobials and eubiotics are necessarily prescribed. Digestive enzymes, sorbents, antispasmodics and analgesics are used as symptomatic treatment.
Prognosis and prevention
With a diffuse invasive form of intestinal candidiasis, the prognosis is serious, since it can lead to generalization of the process. The prognosis for invasive intestinal candidiasis is significantly burdened by the presence of severe background diseases. With other variants of the disease, the prognosis is favorable with the timely start of treatment.
Prevention of intestinal candidiasis consists in the elimination of factors predisposing to this pathology; treatment of diseases of the digestive tract leading to dysbiosis. To maintain a normal intestinal microflora, you should eat a variety of foods, limiting the content of simple carbohydrates, and consume a sufficient amount of fiber. Patients at risk for the development of candidiasis of the gastrointestinal tract (HIV, severe endocrine pathology, polychemotherapy, treatment with corticosteroid hormones, etc.) require close attention and regular examination.