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Biomedical subjects

C Lok

Publications and source records attributed to C Lok.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Plaque variant of trichoblastic fibroma].

BACKGROUND: Tricoblastic fibroma is a rare benign skin tumor originating in the hair follicle. There are two clinical presentations: nodular and plaque variants. The plaque variant is almost exclusively located on the face with deep tissue infiltration. CASE REPORT: A 38-year-old man presented with a 2 cm diameter cutaneous plaque located on the right cheek. It had first been noted by the patient 3 years earlier and had enlarged slowly. On examination, the plaque was well defined, yellowish and slightly indurated. The first clinical diagnosis was basal cell carcinoma and the plaque was removed. Histology provided the diagnosis of trichoblastic fibroma. The patient remains well, with no evidence of recurrence, 10 months after excision. DISCUSSION: Trichoblastoma is an inclusive term for all benign cutaneous neoplasms that are mostly composed of follicular germinative cells. According to Altman, the plaque variant of trichoblastic fibroma is a poorly circumscribed neoplasm, particularly at its lateral and deep margins. This author also states that mitotic figures are more numerous in the plaque variant of trichoblastic fibroma and considers this clinical variant as a low-grade follicular malignancy.

Adult↗
PubMed2001

[MELAS syndrome (mitochondrial encephalopathy with lactic acidosis and stroke-like episodes].

BACKGROUND: The MELAS syndrome (Mitochondrial Encephalopathy, Lactic Acidosis and Stroke-like episodes) belongs to the category of mitochondrial disorders. The most common molecular etiology of the syndrome is a mutation A to G transition at base pair 3243 in the mitochondrial genome. The phenotype is varied and depends on the proportion of DNA muted and which organ on aerobic metabolism suffers most. CASE-REPORT: An 17 year-old woman had successively neurosensory hearing loss, renal disease, cardiomyopathy, diabetes mellitus, lactic acidosis and stroke-like episodes that evoked a MELAS syndrome. DISCUSSION: The skin manifestations of patients with MELAS syndrome are scaly, pruritic, diffuse erythema, reticular pigmentation, moderate hypertrichosis, seborrheic eczema, atopy and vitiligo. Our patient presented severe hirsutism and reticular pigmentation of the limbs. No abnormal histologic and electron microscopic findings were noted in the skin or the follicles involved.

Adolescent↗
PubMed2000

Delays in diagnosis and melanoma prognosis (II): the role of doctors.

A prospective survey was conducted to assess physician responsibility in melanoma prognosis. Consecutive patients with primary melanoma were interviewed and examined using a standardized questionnaire. Main outcome measures were medical components of the delay before tumor resection and tumor thickness. Of 590 melanomas, 29.1% were coincidentally detected by physicians and their tumor depth was lower than in melanomas detected by patients (p < 0.001). Physician sensitivity for melanoma diagnosis was evaluated at 86%. Median time intervals to propose resection and to perform removal of melanoma were short: 0 (mean 103) and 7 (mean 68) days, respectively. Melanomas were managed in an inappropriate way in 14.2% of cases. Location on acral areas and absence of pigmentation were associated with longer medical delays and more frequent inappropriate medical attitudes. Melanomas located on hardly visible areas were less frequently detected by physicians than those on visible areas. Medical delays were shorter, doctor's attitude was more frequently appropriate, and melanoma thickness was lower (p < 0.001) when the patient visited a dermatologist (54.7%) than when he or she visited a general practitioner (33.4%). Our study shows that doctor responsibility accounts for only a small part of the total delay before melanoma removal. However, systematic total examination and better training of doctors, especially about unusual forms of melanoma, could still improve melanoma detection.

Attitude of Health Personnel↗
PubMed2000

Delays in diagnosis and melanoma prognosis (I): the role of patients.

A prospective survey was conducted to assess the role of patients in the melanoma prognosis. Consecutive patients with primary melanoma were interviewed and examined using a comprehensive questionnaire including a psychological instrument. Main outcome measures were the delay before medical intervention and the tumor thickness. Of 590 melanomas, 70.8% were detected by patients and this proportion was higher in females. Relatives were involved in the detection of half of the cases. Median delays before the patient realized he had a suspicious lesion, before this lesion was seen by a doctor, and before the melanoma was removed were 4 months, 2 months, and 1 week, respectively. Delays up to several years were observed in some cases. The rate of self-detection tended to be lower, the delays before seeking medical advice to be longer, and the tumor thickness to be higher in old people, in males, in lower-educated individuals, in those living out of towns, and in people with a low awareness about melanocytic tumors than in other cases. Conversely, individuals with a high number of atypical nevi, those who were aware to be at risk, and those who regularly visited a dermatologist tended to detect their melanoma more rapidly. No specific psychological traits were associated with a late reaction, although negligence and anxiety tended to prolong the delays. Knowledge about melanoma was poor in many patients, especially in males, and wrong beliefs were widespread. This study provides the targets of future education programs.

Adolescent↗
PubMed2000

Pulmonary embolism and transitory anti-beta2-GPI antibodies in an adult with chicken pox.

Anti-beta2-glycoprotein I antibodies are considered as a specific marker for the antiphospholipid syndrome. In contrast to lupus circulating anticoagulant and anticardiolipin (aCL) antibodies, they are usually not found at significant levels in infections. We report a case of pulmonary embolism in an adult with varicella. Transient significant levels of aCL antibodies and of IgM anti-beta2-GPI antibodies were observed. No other prothrombotic factor, including free protein S antigen deficiency, was found. The direct pathogenic role of these transient antibodies on the thrombotic event may then be suspected. They are probably associated with VZV acute infection and are absent two months after varicella.

Adult↗
PubMed1999

Melanoma and tumor thickness: challenges of early diagnosis.

OBJECTIVE: To test the basic assumption of campaigns for early diagnosis of melanoma, ie, prognosis is correlated with the delay in the diagnosis. DESIGN: Prospective study of the correlation between delays to diagnosis, assessed using a questionnaire, and the Breslow thickness as a prognosis marker. SETTING: Dermatology departments in France. PATIENTS: Five hundred ninety consecutive patients, referred within 12 weeks after resection of cutaneous melanoma. MAIN OUTCOME MEASURES: Assessment of 5 successive time intervals from the first time the patients realized that they had a lesion until the resection of the melanoma, and results of the correlation between each time interval and tumor thickness (Breslow). RESULTS: There is a positive but weak correlation between tumor thickness and the delay to identify a lesion as suspicious (r = 0.17; P = .009). However, this delay tends to be short for the thickest tumors. There is a negative correlation between tumor thickness and the delay to seek medical attention (r = -0.20; P<.001). This delay was shorter for nodular melanoma. No correlation is found between melanoma thickness and physicians' delays. CONCLUSIONS: Poor prognosis can be accounted for by aggressive rapidly growing tumors rather than by delays. In well-informed populations, campaigns for early diagnosis of melanoma may thus no longer have a major impact on prognosis, unless they are focused on subgroups less accessible to information and medical care.

Female↗
PubMed1999

Leg ulcers and hydroxyurea: forty-one cases.

BACKGROUND: Hydroxyurea is an antitumor agent used to treat chronic myeloproliferative disorders. Leg ulcerations have been reported in patients undergoing long-term hydroxyurea therapy for myeloproliferative diseases. To better define this dermatological adverse effect of hydroxyurea therapy and to try to understand the pathophysiological process of this disease, we collected medical information for such patients in a multicenter retrospective study. OBSERVATIONS: Forty-one patients (mean age, 67 years) developed leg ulcerations while undergoing hydroxyurea therapy (mean therapy duration, 5 years). The sex ratio was 1, and there was no underlying vascular disease. Hematologic abnormalities were identified. Complete recovery from the ulcerations occurred quickly after withdrawal of treatment in 33 (80%) of the cases. CONCLUSIONS: This longest-reported series of patients confirms the role of hydroxyurea therapy in the onset of leg ulcerations. Healing or improvement requires cessation of treatment. Cutaneous atrophy and impaired wound healing may explain the relationship between hydroxyurea and leg ulcers. In addition, the megaloblastic erythrocytes resulting from the presence of hydroxyurea may circulate poorly through the capillary network. A prospective study in hematologic centers would be valuable.

Adult↗
PubMed1999

EMLA cream as a topical anesthetic for the repeated mechanical debridement of venous leg ulcers: a double-blind, placebo-controlled study.

BACKGROUND: A granulating surface is important for skin grafting and healing of leg ulcers. Mechanical debridement to remove necrotic tissue often must be stopped before completion because of pain. OBJECTIVE: Our purpose was to assess the effect of EMLA cream on the number of debridements required to obtain a clean ulcer and on pain during debridement and to determine its safety after repeated doses. METHODS: In this randomized double-blind, placebo-controlled study, 69 patients with venous leg ulcers received cream before debridement until a clean ulcer was obtained (or a maximum of 15 debridements). RESULTS: EMLA decreased the median number of debridements required for a clean ulcer (EMLA 11.5, placebo >15; P = .019) and decreased pain by 50% (P = .003). Plasma levels of lidocaine, prilocaine, and their main metabolites were low without any apparent accumulation. CONCLUSION: EMLA produces effective pain relief for the debridement of leg ulcers and shortens the time to a clean ulcer.

Administration, Cutaneous↗
PubMed1998

Randomised trial of interferon alpha-2a as adjuvant therapy in resected primary melanoma thicker than 1.5 mm without clinically detectable node metastases. French Cooperative Group on Melanoma.

BACKGROUND: Owing to the limited efficacy of therapy on melanoma at the stage of distant metastases, a well-tolerated adjuvant therapy is needed for patients with high-risk primary melanoma. Our hypothesis was that an adjuvant treatment with low doses of interferon alpha could be effective in patients with localised melanoma. METHODS: After resection of a primary cutaneous melanoma thicker than 1.5 mm, patients without clinically detectable node metastases were randomly assigned to receive either 3x10(6) IU interferon alpha-2a, three-times weekly for 18 months, or no treatment. The primary endpoint was the relapse-free interval. FINDINGS: 499 patients were enrolled, of whom 489 were eligible. When used as part of a sequential procedure, interferon alpha-2a was of significant benefit for relapse-free interval (p=0.038). A long-term analysis, after a median follow-up of 5 years, showed a significant extension of relapse-free interval (p=0.035) and a clear trend towards an increase in overall survival (p=0.059) in interferon alpha-2a-treated patients compared with controls. There were 100 relapses and 59 deaths among the 244 interferon alpha-2a-treated patients compared with 119 relapses and 76 deaths among the 245 controls. The estimated 3-year-relapse rates were 32% in the interferon alpha-2a group and 44% in controls; the 3-year death rates were 15% and 21%, respectively. Only 10% of patients experienced WHO grade 3 or 4 adverse events. Treatment was compatible with normal daily life. INTERPRETATION: Adjuvant therapy of high-risk melanoma with low doses of interferon alpha-2a for 18 months is safe and is beneficial when started before clinically detectable node metastases develop.

Antineoplastic Agents↗
PubMed1998

High risk of death in elderly patients with extensive bullous pemphigoid.

OBJECTIVE: To evaluate survival and factors predicting death in bullous pemphigoid. DESIGN: Retrospective analysis of cohort. SETTING: Three referral centers (university hospitals). PATIENTS: Among 237 patients recruited between January 1, 1985, and December 31, 1992, 20 were excluded because of doubtful diagnosis. The 217 remaining patients were 79+/-11 years old (mean+/-SD); 120 were women and 97 were men; and 79% had been treated with oral corticosteroids, 40 to 90 mg/d. INTERVENTIONS: Missing information on follow-up was minimized by letters and/or telephone calls to patients, families, nursing homes, and physicians. MAIN OUTCOME MEASURES: Actuarial survival curve, compared with the expected curve as derived from census data, and evaluation of prognostic factors by comparing initial characteristics between patients alive at 6 months and these who died before that point. RESULTS: Survival curve demonstrated an early increased mortality: 17% at 3 months and 31% at 6 months, mainly from sepsis and cardiovascular diseases. Of the factors related to bullous pemphigoid activity (duration; pruritus; and number and extent of blisters, eosinophilia, and serum antibodies) only generalized pemphigoid was predictive of death in comparison with localized forms. In multivariate analysis, age of 86 years or more (relative risk, 7.1; 95% confidence interval [CI], 2.0-25.4; P < or = .01), poor general condition (relative risk, 8.2; 95% CI, 3.0-22.4; P < or = .001), female sex (relative risk, 2.4; 95% CI, 1.1-5.4; P < or = .05), and generalized disease (relative risk, 4.4; 95% CI, 1.4-13.7; P < or = .01) were associated with increased risks of death at 6 months. CONCLUSION: In this series, generalized bullous pemphigoid had a poor prognosis especially in older patients and those in poor general condition.

Aged↗
PubMed1998

Evaluation of clinical criteria for diagnosis of bullous pemphigoid. French Bullous Study Group.

OBJECTIVE: To check the potential usefulness of clinical criteria for the diagnosis of bullous pemphigoid when state-of-the-art techniques such as Western immunoblotting, immunoprecipitation, and indirect immunofluorescence on salt-split skin or direct immunoelectron microscopy are not available. DESIGN: Comparison of the clinical criteria between 2 groups (with and without bullous pemphigoid) as defined by immunoelectron microscopy used as standard criterion, in a prospective study. Multivariate logistic regression analysis was carried out by including all items that were statistically significant (at P < .05 level) in univariate analysis. SETTING: Five dermatology departments in teaching hospitals. PATIENTS: The 231 patients studied had subepidermal autoimmune bullous diseases with linear IgG or C3 deposits in the basement membrane zone (157 with bullous pemphigoid, 33 with cicatricial pemphigoid, 30 with epidermolysis bullous acquisita, 5 with lupus erythematosus, and 6 others). A second set of patients was used to calculate predictive values. RESULTS: The multivariate logistic stepwise analysis resulted in a final set of predictors that included only 4 items: absence of atrophic scars, absence of head and neck involvement, absence of mucosal involvement, and age greater than 70 years. No additional variables met the .05 significance level to enter into the model. If 3 of these 4 characteristics were present, a diagnosis of bullous pemphigoid could be made with a sensitivity of 90% and a specificity of 83%; these predictive values were calculated on a sample of 70 new cases. CONCLUSIONS: With and estimated incidence of bullous pemphigoid among subepidermal autoimmune bullous diseases of 80%, the presence of 3 of the 4 significant criteria allows the diagnosis of bullous pemphigoid, with a positive predictive value of 95%. Our set of clinical criteria thus allows the diagnosis of bullous pemphigoid with good validity for both clinical practice and therapeutic trials.

Aged↗