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N Tsankov

Publications and source records attributed to N Tsankov.

At least 19 recordsLinked to original sources
PubMed2003

Intra-individual comparison of the cutaneous safety and efficacy of calcitriol 3 microg g(-1) ointment and calcipotriol 50 microg g(-1) ointment on chronic plaque psoriasis localized in facial, hairline, retroauricular or flexural areas.

BACKGROUND: Psoriasis involving sensitive skin areas remains difficult to treat because of the side-effects of topical corticosteroids and the irritancy potential of vitamin D3 derivatives. Several clinical trials have demonstrated that calcitriol, the naturally occurring and hormonally active form of vitamin D3, is effective and safe at the dose of 3 microg g(-1) for the treatment of psoriasis affecting the trunk and limbs. METHODS: We compared the safety and efficacy of calcitriol 3 microg g(-1) ointment and calcipotriol 50 microg g(-1) ointment in a multicentre, randomized, investigator-blinded, left-right comparison in mild to moderate chronic plaque psoriasis affecting sensitive areas, defined as being the face, hairline, retroauricular and flexural areas. One pair of symmetrical and bilateral target lesions was selected from each area and assessed for perilesional erythema, oedema, and stinging/burning. Global assessment of local tolerability and global improvement were rated by the investigator, and the subjects were asked to evaluate the tolerability and efficacy of each product and to express their global preference. RESULTS: In the 75 subjects, calcitriol and calcipotriol both led to clearing of at least one target lesion in 21 (28%) of the subjects each. Perilesional erythema (P < 0.001), perilesional oedema (P < 0.02) and stinging/burning (P < 0.001) were all significantly less severe with calcitriol than with calcipotriol. The subjects' evaluation of local tolerability was significantly (P < 0.0001) in favour of calcitriol. Ten treatment-related dermatological events occurred in eight subjects, including one subject who experienced skin discomfort on both sides. All other events occurred only on the calcipotriol-treated side (irritant dermatitis, six subjects; contact dermatitis, one subject). Global assessment of improvement from baseline by the investigators was significantly greater for the calcitriol-treated lesions (P < 0.02). The subjects' global preference was significantly in favour of calcitriol (P < 0.02). CONCLUSIONS: In the present study, calcitriol ointment was found to be better tolerated and would appear to be more effective than calcipotriol ointment in the treatment of psoriasis in sensitive areas.

Adolescent↗
PubMed2002

Melanoma progression and serum L-dopa/L-tyrosine ratio: a comparison with S100B.

The challenge to find a reliable tumour marker for the management of melanoma patients still remains. In this study, the serum L-dopa/L-tyrosine ratio was compared with serum S100B as a reference marker. A total of 89 melanoma patients were sampled and staged according to the American Joint Committee on Cancer (AJCC) classification. Of these, 19 stage III and 28 stage IV patients were evaluated for disease progression at 1.5 years and 6 months post-sampling, respectively. Serum L-dopa and L-tyrosine were measured by high performance liquid chromatography (HPLC) (normal value for ratio < 16 x 10(-5)) and S100B using the LIA-mat Sangtec 100 assay (normal value < 0.10 microg/l). Non-parametric tests (Kruskal-Wallis analysis of variance, Dunn's and Spearman) were used for the statistical analysis. The median serum L-dopa/L-tyrosine ratio was 16.0 x 10(-5) (range 2.7-545.1 x 10-5 and the median S100B level was 0.15 microg/l (range < 0.10-13.8 microg/l), with a sensitivity of 51% for the ratio and 66% for S100B. There was a 47% discordance and no correlation between the two markers (r = 0.149). The ratio was higher in stage IV than in other stages (P < 0.05), as was the S100B level (P < 0.0001). Both markers were higher in patients with evolutive disease (n = 23) than in stable patients (n = 24), with values of 20.8 x 10(-5) versus 13.1 x 10(-5) for the ratio (P < 0.05) and 0.89 microg/l versus 0.16 microg/l for S100B (P < 0.001); for the ratio, this difference was more pronounced in stage III than in stage IV patients. The overall sensitivity and specificity of the markers to predict disease progression were 78% and 67%, respectively, for the ratio, and 74% and 83%, respectively, for S100B (using an ROC cut-off of 0.38 microg/l). In conclusion, the serum L-dopa/L-tyrosine ratio correlates with melanoma progression and has predictive value, especially in stage III patients. This tumour marker, like S100B, could serve as an additional tool in the management of melanoma.

Adult↗
PubMed2001

Pemphigus vulgaris: environmental factors. Occupational, behavioral, medical, and qualitative food frequency questionnaire.

BACKGROUND: There have been reports suggesting the involvement of environmental factors in the disease process of pemphigus. Factors suggested include exposure to pesticides or certain drugs. OBJECTIVE: To analyze the association of pemphigus with environmental exposure to various agents, including smoking, recreational and occupational insults, drugs, and food. DESIGN AND SETTING: In-person interviews of pemphigus patients and control subjects were conducted by trained medical investigators using a structured questionnaire. Questions included occupational, behavioral, medical, and qualitative food frequency details. The multicenter study was conducted at outpatient services of teaching hospitals in Bulgaria, Brazil, India, Israel, Italy, Spain, and the USA. PARTICIPANTS: A total of 126 pemphigus patients (55 men, 71 women; age, 54 +/- 17 years) and 173 healthy controls (87 men, 86 women; age 50 +/- 19 years) were interviewed in the period between October 1, 1999 and March 31, 2000. The diagnosis of pemphigus was based on clinical, histologic, immunohistologic, and immunohistochemical criteria. The disease duration was 2-27 years (8.4 +/- 7.2 years). Individuals with skin diseases other than pemphigus were selected as control subjects. MAIN OUTCOME MEASURE: Information on drugs, foods, and occupational, environmental, constitutional, and other possible risk factors was analyzed by t-tests and chi-squared tests as applicable. A multivariate logistic regression model was applied to the data to study simultaneously the independent relationship between each risk factor and pemphigus vulgaris. RESULTS: The risk for pemphigus vulgaris was lower for ex-smokers and current smokers than for patients who had never smoked. Exposure to pesticides and occupational exposure to metal vapor were associated with an increased risk of pemphigus. Pemphigus patients had more pregnancies than controls. There were differences in environmental factors between countries, with exposure to gardening materials and pesticides being highest among patients from Bulgaria, followed by Israel. Disease characteristics also exhibited differences between countries. Bulgarian patients less frequently had oral mucous membrane lesions: 66% compared to 92% for Israeli patients and 83% for Italians. The distribution of the disease in skin and mucous membranes was similar among patients from all countries. Exclusive skin involvement was seen in 50% of patients, mucous membranes alone in 23% of patients, and both skin and mucous membranes in 27% of patients. CONCLUSIONS: The beneficial effect of smoking on pemphigus might be explained by its effect on the immune system. In addition, smoking has an antiestrogenic effect, while pesticides have an estrogenic effect. The lower numbers of smokers among patients, the higher exposure rates to pesticides, and the higher number of female patients who had been pregnant may point to the contribution of estrogens to the disease process. It remains to be determined whether measures, such as avoiding exposure to pesticides or metal vapor, may be beneficial in the clinical context. As the present study was a survey, more definitive studies should be conducted to validate the results.

Agriculture↗
PubMed2000

Epidemiology of pemphigus in Sofia, Bulgaria. A 16-year retrospective study (1980-1995).

BACKGROUND: Pemphigus is a disease showing an uneven geographical distribution. In Bulgaria pemphigus has always represented a substantial part of diagnosed bullous diseases, but previous epidemiological data are incomplete. Our purpose was to evaluate retrospectively the incidence and prevalence of pemphigus in the district of Sofia (the capital of Bulgaria; population 1 200 000) for a sixteen-year period. METHODS: The files of all the newly registered patients with pemphigus in the City Hospital of Dermatology in Sofia during the period Jan 1 1980 to Dec 31 1995, were collected and analysed with regard to personal statistics, ethnic origin, profession, history of the disease including age and season of onset, symptoms, clinical diagnosis, severity, laboratory findings, associated illnesses, therapy, and cure rate. Special attention was paid to smoking, alcohol abuse, and the presence of triggering factors such as emotional stress, drug intake, underlying diseases, neoplasias, or others. RESULTS: During the 16-year period studied, 74 newly diagnosed cases of pemphigus occurred in the district of Sofia, giving a prevalence of 0.38 per 100 000 inhabitants and a mean incidence of 0.47/100 000/year for the overall population and 0.51/100 000/year for the population aged above 20 years. The most common clinical variant is pemphigus vulgaris, frequently occurring in the fifth-sixth decades. The vast majority of the patients are workers or professionals. CONCLUSIONS: The results of the present retrospective study reveal a relatively high prevalence and incidence of pemphigus in Bulgaria, compared to that encountered in other countries. Our data is similar to that reported from Greece. Whether the Balkan Peninsula represents a focus of population groups with high susceptibility to pemphigus is a problem which could be highlighted by further epidemiological studies in this geographic area.

Adult↗
PubMed2000

Epidemiology of syphilis in Bulgaria, 1990-1998.

There have been great political, social and economic changes in Bulgaria since 1990 with higher incidences of syphilis when compared with the previously controlled morbidity of syphilis. There has been a 7-fold increase in 1998 compared with 1990. The male/female ratio remained the same 1.2:1. A higher number of cases was reported in cities than in villages and small towns, 80.68% in 1990; 73.4% in 1998. The number of employed patients with syphilis has decreased during the years--from 75.5% in 1990 to 44% in 1998, with a corresponding increase in syphilis in the unemployed. The age group at highest risk is 20-24 years, 28.7% in 1991; 24% in 1998. The least affected group are those older than 55--the incidence being 6.34% in 1990; 2.6% in 1997 and 4% in 1998. The prevalence of the different stages of early infection remained the same. The incidence of congenital syphilis increased from 1 in 1990 and 1991 to 21 in 1996, 29 in 1997 and 35 in 1998.

Adult↗
PubMed1999

Livedo reticularis and cerebrovascular accidents (Sneddon's syndrome) as a clinical expression of antiphospholipid syndrome.

We present two patients with livedo reticularis and cerebrovascular accidents (Sneddon's syndrome) and positive anticardiolipin antibodies. We suggest that these antibodies may be pathophysiologically related to the clinical manifestation observed in some patients with this syndrome. When Sneddon's syndrome is associated with positive anticardiolipin antibodies it could be regarded as antiphospholipid syndrome and fall into this category of nosological entity.

Aged↗
PubMed1998

Contact pemphigus induced by dihydrodiphenyltrichlorethane.

We describe a case of contact pemphigus, a new subgroup of induced pemphigus. The disease is provoked by a chlorinated hydrocarbon pesticide: dihydrodiphenyltrichlorethane. We suspect that systemic absorption after the topical contact is responsible for the alteration of skin structure and activation of immunological mechanisms leading to blister formation and acantholysis.

Agricultural Workers' Diseases↗
PubMed1990

[The diagnosis and treatment of cancer of the papilla of Vater].

The diagnostic possibilities for early detection of cancer of the duodenal papilla are discussed. A scheme is suggested for examination of patients suspected of having cancer of the papilla. The advantages of radical operation, providing longer survival are pointed out. A patients is reported, who survived 16 years after duodenopancreatectomy for cancer of the duodenal papilla.

Aged↗
PubMed1988

Psoriasis and drugs: influence of tetracyclines on the course of psoriasis.

Patients with psoriasis vulgaris (462) were studied by questionnaire to find the effect on psoriasis of drug therapy for intercurrent diseases or focal infections. Of 462 patients with psoriasis, in 76 (16.45%) the disease became more severe during drug therapy. Of these, 19 worsened after administration of tetracyclines, and in five psoriasis was precipitated after therapy with drugs of the tetracycline family. We suggest that tetracyclines should be avoided in patients with psoriasis and in healthy persons with a genetic predisposition (positive family history, human leukocyte antigens B13, B17, B27).

Ampicillin↗