RU2393774C1 - Method of differential diagnostics of psoriatic onychodystrophy and onychomycosis - Google Patents

Abstract

FIELD: medicine. ^ SUBSTANCE: invention relates to medicine, namely to dermatovenerology, and can be used in differential diagnostics of psoriatic onychodystrophy and onychomycosis. Patient's level of interferons is determined, if values of interferon- (IFN-) induced are normal psoriatic onychodystrophy is diagnosed, if level of (IFN-) induced is reduced in comparison with the norm, mycologic examination is carried out and results are used to make conclusion about onycomycosis. ^ EFFECT: method allows to determine group of psoriasis patients with suspected onycomycosis for administration of complex mycological examination in order to establish definitive diagnosis. ^ 2 ex

Description

The invention relates to medicine, namely to dermatovenerology, and can be used in the differential diagnosis of psoriatic onychodystrophy and onychomycosis.

With psoriasis, nail damage (psoriatic onychodystrophy) is often observed, not associated with mycotic infection, and in most cases it manifests itself in the formation of multiple point depressions on the nail plates, loosening, thickening or detachment of the nail. Lesions in psoriatic onychodystrophy are clinically similar to fungal infections of the nails (onychomycosis).

A known method for the differential diagnosis of psoriatic onychodystrophy and onychomycosis, according to which a mycological examination is carried out, including microscopic and cultural studies of the material from the affected nail plates (R.A. Arabian, N.N. Klimko, N.V. Vasilieva. "Diagnosis of mycosis" Publishing House SPbMAPO, 2004, pp. 72-73), the results of which judge the nature of the lesion.

However, the appointment of a comprehensive mycological examination for all patients with psoriasis with signs of nail damage is impractical due to the high cost and duration of the diagnostic procedure, as well as the low detectability of fungi in various laboratories (from 30% to 60%), which does not allow us to speak with confidence about the presence or lack of infection.

The technical result achieved by the invention is to isolate a group of patients with psoriasis with suspected onychomycosis for the purpose of a comprehensive mycological examination.

The invention consists in achieving the claimed technical result in a method for differential diagnosis of psoriatic onychodystrophy and onychomycosis, according to which the level of interferons is determined, at normal values of interferon-γ (IFN-γ) induced, psoriatic onychodystrophy is diagnosed, and when the level of IFN-γ induced is reduced compared to the norm is mycological examination, according to the results of which they judge onychomycosis.

It is known that infection with fungal infections indicates a decrease in the activity of the cellular immune response. This can be caused by endocrinopathies, hypovitaminosis, metabolic disorders, chronic diseases, the use of antibiotics and cytostatics. Cellular immunity performs the functions of protecting the body from intracellular infections. This type of immune response is mediated by T × 1 producing IFN-γ, which significantly increases the microbicidal activity of macrophages. This leads to the successful destruction of pathogens, including fungi. Therefore, it can be assumed that the complication of the course of psoriasis with onychomycosis is an indicator of a decrease in T × 1 activity. In addition, the nail plate is the entrance gate to the infection, as well as a medium for the growth of the fungus, and, therefore, antigenic load, in turn, can overwhelmingly affect the cellular immune response.

The authors conducted clinical studies of 24 patients with exudative form of psoriasis. The age of the examined from 31 to 58 years, the duration of the disease from 3 to 10 years. The area of damage to the skin ranged from 40 to 70%. In all patients with damage to the nail plates of the feet, a combination of point impressions, onycholysis and subungual hyperkeratosis was noted. Patients selected for the study had similar concomitant diagnoses, received standard detoxification and anti-inflammatory therapy. The first group of patients was 15 patients with psoriasis with onychodystrophy. The second group - 9 patients with psoriasis and onychomycosis.

When examining the level of interferons in patients of the first group, deviations from the norm were not detected. In patients of the second group, a significant decrease in IFN-γ induced compared with the norm was revealed. Thus, it is advisable to study the interferon status in order to increase the information content of the diagnosis of onychomycosis in patients with psoriasis.

The method is carried out, for example, as follows.

An immunological study is performed on the patient, at normal values of IFN-γ induced (N 500-2000 pg / ml), psoriatic onychodystrophy is diagnosed, and with a decrease in the level of IFN-γ induced compared to the norm, mycological examination is carried out, including microscopic and cultural examination of the material from the affected nail records, and on its results judge onychomycosis.

The method is illustrated by the following clinical examples.

1. Patient M., 52 years old, turned to the outpatient department of the mycological clinic with complaints of rashes accompanied by itching on the face, trunk, upper and lower extremities, changes in the nail plates of the hands and feet.

From the anamnesis of the disease, it is known that the patient suffers from psoriasis for 12 years, she was repeatedly hospitalized on this occasion. Exacerbation of psoriasis annually in the spring-autumn period. I noted changes in the nail plates 5 years ago, during the period of remission of the skin process, the state of the nails does not change.

Upon admission, the skin process was common. It was localized on the trunk, upper and lower extremities, mainly on extensor surfaces. It is represented by numular and miliary papules and plaques up to 4 cm in diameter with clear borders, pink-red in color with silver scales on the surface, a peripheral growth zone with a tendency to merge. Psoriatic triad (+). Dermographism is red. Troprop skin and all kinds of sensitivities preserved. Lard and sweating in the foci is reduced. The nail plates of the hands and feet are changed. On the hands, the nails are changed according to the distal-lateral type to 1/2 length, the nail plates 1; 2; four; 5 fingers of the right and 1-3 fingers of the left hand have point impressions of the “thimble” type, regional onycholysis was observed, the surface of the nail is smooth, cloudy, white-yellow. The nail plates of the feet are totally affected: thickened, crumbling, white-yellow. The skin of both feet and the right hand is hyperemic with copious flour-like peeling.

Survey results.

An immunological study was performed on the patient: IFN-α spontaneous 0 pg / ml (N 0-30 pg / ml), IFN-α induced 466 pg / ml (N 100-500 pg / ml), IFN-γ spontaneous 35 pg / ml (N 0-50 pg / ml), IFN-γ induced 426 pg / ml (N 500-2000 pg / ml). The study showed a decrease in the level of IFN-γ induced compared to normal.

Scraping of the nail and skin scales of the hands and feet was taken. Mycosis and onychomycosis of the feet is confirmed by the detection of dermatomycete mycelium by microscopy of skin and nail scales and the isolation of T. rubrum in a culture study.

2. Patient T., 49 years old, was admitted to a mycological clinic with complaints of rashes, accompanied by itching, on the scalp, trunk, upper and lower extremities, changes in the nail plates of the hands and feet.

From the anamnesis of the disease, it is known that the patient suffers from psoriasis for 23 years, and has been hospitalized several times on this occasion. Changes in the nail plates over the past 3 years during the period of exacerbation of the underlying disease.

Upon admission, the skin process was common. It was localized on the scalp, trunk, extensor surfaces of the upper and lower extremities. Rashes are represented by lenticular and numular papules and plaques up to 5 cm in diameter with clear boundaries. The skin of the scalp is affected by the type of "helmet", the borders of the plaque go beyond the hair growth zone on the skin of the forehead and in the behind-the-ear folds. Rashes have a stagnant red color, clear boundaries, covered with silver scales with a zone of peripheral growth. Within the plaque cracks, hemorrhagic crusts. Psoriatic triad (+). Dermographism pink. Skin turgor and all kinds of sensitivities preserved. Lard and sweating in the foci is reduced. Nail plates of brushes and feet are changed according to the “thimble” type. On all fingers of the hands, the marginal and central onycholysis, on the 1st and 2nd finger of the right hand are subungual hemorrhages, the nail plates are not thickened. The nail plates of the feet are totally affected: subungual hyperkeratosis, the nails crumble, white-yellow in color, on the nail plates of 1 fingers the phenomenon of distal onycholysis. The skin of both feet and hands is hyperemic with abundant mid-plate peeling.

Survey Results:

An immunological study was performed on the patient: IFN-α spontaneous 6 pg / ml, IFN-α induced 535 pg / ml, IFN-γ spontaneous 18 pg / ml, IFN-γ induced 608 pg / ml.

The level of IFN-γ induced, which is within normal limits, testified to the presence of psoriatic onychodystrophy in the patient, however, scraping of the nail and skin scales of the hands and feet was taken for control of the patient. Microscopy revealed no fungal mycelium; when sowing, mushroom growth is absent.

Thus, the use of the claimed method allows you to select a group of patients with psoriasis with suspected onychomycosis for the appointment of a comprehensive mycological examination to establish a final diagnosis.

Claims (1)

A method for differential diagnosis of psoriatic onychodystrophy and onychomycosis, including determining the level of interferons, with normal values of interferon-γ induced, diagnose psoriatic onychodystrophy, and with a decrease in the level of interferon-γ induced compared with the norm, a mycological examination is carried out, according to which they judge onychomycosis.