Histologic pitfalls in the Mohs technique.

The success of the Mohs procedure depends on the reliability of each step in the technique. Pitfalls in histologic preparation of the tissue specimens may occur during debulking, excising, orienting, creating the map, sectioning, inking, tissue flattening and freezing, cutting, slide fixation, staining, and mapping the tumor. Challenges are also present in interpreting the slides. Diagnostic pitfalls include floaters, inflammatory conditions resembling tumor, and perineural invasion. The technique requires time, teaching, and a sufficient quantity of cases from which to learn, as well as attention to the pitfalls that occur while processing tissue specimens and interpreting and mapping the histology.

Malignant skin neoplasms.

Skin cancers may be derived from any part of the skin, and the classification of all variants is extensive. Overall they are the most common cancers of the body, and include those that are highly mortal and those that are associated with an increased morbidity. In this review the most common skin cancers confronted by the clinician and their management are discussed. New associations are highlighted, as well as new information that can help the clinician to better understand the pathogenesis of many of these entities.

The prevalence of psoriatic arthritis in psoriatic patients in Tehran, Iran.

BACKGROUND: Psoriatic arthritis is an inflammatory arthritis which is associated with psoriasis. There is no general agreement in the literature regarding the epidemiology of psoriatic arthritis. In this study, we evaluated the prevalence of psoriatic arthritis in a relatively large number of psoriatic patients. METHODS: Three hundred and twenty patients with psoriasis were evaluated in a cross-sectional study. The psoriasis area and severity index, family history, demographic variables, and some other factors (e.g., clinical type and location of the disease) were assessed. The patients were examined for signs of arthropathy and the suspects were referred to a rheumatologist for further evaluation and confirmation of the diagnosis. RESULTS: Psoriatic arthritis was observed in 29 (9.1%) patients. The prevalence of Psoriatic arthritis in men (10.1%) was not statistically different from that of women (7.8%). The most common type of psoriasis in all patients, with and without psoriatic arthritis, was chronic plaque psoriasis. The mean+/-SD psoriasis area and severity index was significantly (P<0.05) higher in patients with psoriatic arthritis (24.33+/-10.36) than those without psoriatic arthritis (10.70+/-8.44). Nail involvement was significantly more common in patients with psoriatic arthritis than those without psoriatic arthritis. HLA B27 was the most common HLA detected in patients with psoriatic arthritis. CONCLUSION: Dermatologists are usually the first physicians to detect signs and symptoms of psoriatic arthritis and need to work closely with rheumatologists to establish the diagnosis and start appropriate treatments which will address both the skin and the joint disease.

Laser treatment of keloids and hypertrophic scars.

BACKGROUND: Lasers have been used in the treatment of hypertrophic scars and keloids for more than 20 years. Different laser systems have been examined; among them pulsed dye lasers are currently considered the laser of choice in these settings. OBJECTIVES: The purpose of this study is to review the pertinent literature and provide updated information on different laser therapies available for treatment of keloids and hypertrophic scars. METHODS: A Medline literature search was performed for relevant publications. RESULTS: In this review the results of published studies in the treatment and prevention of hypertrophic scars and keloids are presented. Suggested mechanisms of action are reviewed. A review of the optimal laser parameters to modulate treatment outcome will be discussed. Different lasers are effective in not only the treatment but also the prevention of hypertrophic scars and keloids, among them PDL is more promising. Most of the suggested theories are based on the selective photothermolysis in which the light energy emitted from a vascular laser is absorbed by hemoglobin, generating heat and leading to coagulation necrosis, neocollagenesis, collagen fiber heating with dissociation of disulfide bonds and subsequent collagen fiber realignment. CONCLUSION: The optimal laser is currently 585 nm PDL, although the recent results of Q-switched 532 nm frequency-doubled Nd:YAG are promising. Early use of lasers are beneficial, especially in those who are prone to develop these lesions.

Comparison of direct smear, culture and histology for the diagnosis of onychomycosis.

A sensitive and efficient diagnostic strategy is needed to confirm the clinical suspicion of onychomycosis. The purpose of this study was to compare the sensitivity of three most commonly used diagnostic methods for onychomycosis. Nail specimens of 96 patients with clinically suspected onychomycosis were evaluated using potassium hydroxide smear, culture and histology. A positive result of any of these tests was considered confirmatory for fungal infection and the sensitivity of each test as well as various combinations of them was calculated. The diagnosis of onychomycosis was confirmed in 47 patients (48.9%). Histology was the most sensitive single test for the diagnosis of onychomycosis, although its sensitivity (80.8%) was not statistically different from smear (76.5%). Both histology and smear were significantly more sensitive than culture (53.2%). The most sensitive combination of tests, smear plus histology, was 97.8% sensitive with 98% negative predictive value. In conclusion, direct smear combined with histological examination is the most sensitive diagnostic approach for onychomycosis.

Nonablative lasers.

The trend toward minimally invasive rejuvenation techniques has led to the widespread use of nonablative lasers. Nonablative lasers can be classified in two groups based on their wavelengths: lasers emitting light in the visible range, and those emitting in the infrared range. In this review, different laser and intense pulsed light (IPL) systems are presented and critically discussed along with findings of the studies in the literature.

New clinical syndromes in dermatology.

Dermatologists are in the unique position to be able to diagnose serious systemic diseases through skin findings; in addition, cutaneous manifestations can be associated with internal symptoms and clarify the pathogenesis and treatment of challenging new syndromes. Calciphylaxix, now renamed Calcific Uremic Arteriolopathy, primarily affects patients with end-stage renal disease with concomitant hyperphosphatemia, increased calcium-phosphate product and hyperparathyroidism, skin biopsy and wound care are crucial parts of the diagnosis and treatment. Hyperhomocysteinemia may play a very important role in many cutaneous and systemic diseases including, chronic cutaneous wounds, systemic lupus erythematosus, Behcet's disease and psoriasis. Through a skin biopsy and biochemical analysis of the proteoglycans accumulation it may be possible to diagnose a new systemic mucinosis and prevent sudden death in patients with severe mitral valve prolapse. Nephrogenic Fibrosing Dermopathy is a newly described fibrosing disorder occurring in patients with end stage renal disease, the etiology and pathogenesis are still unknown, and the ultimate course of this disease has not been defined.

The incidence of recurrent herpes simplex and herpes zoster infection during treatment with arsenic trioxide.

We report the incidence of varicella zoster virus (VZV) and herpes simplex virus (HSV) infection in patients with multiple myeloma and colon cancer who were treated with arsenic trioxide for their disease. In this report, we discuss the effects of arsenic on immune system, and suggest arsenic compounds as a possible predisposing factor for viral reactivation in these patients.

The role of number of treatments in laser-assisted hair removal using a 755-nm alexandrite laser.

BACKGROUND: It is generally accepted that multiple laser treatments yield more effective clinical results; however, it is not clearly known whether increasing the number of treatments would affect the incidence of adverse effect. The main objective of the study was to assess the role of the number of treatments in the efficacy and safety of laser-assisted hair removal in a relatively dark-skinned population. METHODS: A retrospective study of 313 consecutive laser-assisted hair removal treatments was conducted on a total of 23 patients (22 women, 1 man) with 58 anatomic areas by means of an alexandrite laser. Skin types of III and IV were represented. The long-pulsed alexandrite system (Aphrodite, Quanta system, Italy) was used at a 755-nm wavelength to deliver fluences ranging from 17 to 25 j/cm2 through a 10 mm spot size. The patients were divided into 4 groups according to the number of treatments (group I < or =4, group II = 5, group III = 6, and group IV > or =7 treatments). Digital photographs of the patients were used for hair counting. Adverse effects (hyperpigmentation, hypopigmentation, blister, folliculitis) were questioned. The treatment was defined as successful if there was more than 50% hair reduction and an absence of the adverse effects. RESULTS: There was a positive correlation between hair reduction and number of treatments (r = .402, p < .005). The following side effects were observed: hyperpigmentation (two patients, both in group IV); hypopigmentation (one patient in group IV) and blister (one patient in group IV); folliculitis (two patients in group III and IV). Treatment was successful in 48.3% (28 out of 58) of the treatment sites. The success rate was 25% for < or =4 treatments, and 76%, 58%, and 15% for 5, 6, and > or =7 treatments respectively (p = .002). CONCLUSION: Patients who undergo more treatment sessions achieve a higher rate of hair reduction; although this may be concomitant with an increase in the incidence of adverse effects. The benefit of more laser treatments should be balanced with the risk of occurrence of side effects in each patient.

Basal cell carcinoma of the areola in a man.

Basal cell carcinomas (BCCs) that arise in sun-protected sites are quite uncommon. We report a case of BCC of the areola, which is extremely rare. Mohs micrographic surgery was used for the treatment. The etiologic factors of BCCs in sun-protected areas are discussed, and previous studies regarding the treatment modalities are reviewed.

Hair removal using an 800-nm diode laser: comparison at different treatment intervals of 45, 60, and 90 days.

BACKGROUND: Some laser irradiation parameters such as wavelength, fluence, pulse duration, and spot size have been shown to influence the damage of any target inside the skin, however, the role of some patients' factors such as hair growth cycle is still under debate. OBJECTIVE: To determine the association of treatment interval and laser treatment outcome. METHODS: In a retrospective chart review of 176 patients undergoing laser-assisted hair removal with a diode laser 24 patients were selected. All accepted to cease the therapy, and be followed-up for 5 months. At the end of the study the patients were questioned about the efficacy of the treatment as well as the adverse effects. Hair counting was also performed. The adverse effects (pain, blister or erosion, hyperpigmentation, hypopigmentation, and folliculitis) were questioned during the follow-up period. RESULTS: The mean hair reduction was 78.1%, 45.8%, and 28.7% in 45, 60, and 90-day interval groups, respectively (P < 0.0001). CONCLUSION: The treatment interval was related to the treatment outcome in our study.

What patients with vitiligo believe about their condition.

BACKGROUND: Vitiligo is a common disease with an unknown etiology. It is a chronic disease which causes severe disfigurement, and so may significantly affect a patient's quality of life. This study was designed to evaluate the illness perception and quality of life in patients with vitiligo. PATIENTS AND METHODS: A questionnaire consisting of 25 questions on the causes, timeline, consequences, and control of disease was given to 80 patients with vitiligo attending a private skin clinic in Tehran, Iran, in 1999. The roles of age, sex, duration of disease, education, extent of disease, and family history of vitiligo were assessed. RESULTS: Eighty patients (22 males and 57 females, one not mentioned), with a mean age of 30 years (SD = 11 years) and a disease duration of 7.1 years (SD = 7.8 years), completed the questionnaire; 62.5% of the patients believed that stress played a role in their disease; 31.3% believed that their genetic background played a role in their disease, more so in patients with a positive family history of vitiligo. Almost one-half of patients believed that their illness had major consequences on their lives. One-half of patients believed that their illness was likely to be permanent rather than temporary, more so in patients with a longer duration of disease and a higher level of education. Only 60% of patients considered that their treatments were effective. CONCLUSION: Vitiligo may considerably affect various aspects of patients' lives. The knowledge of patients about the causes and course of their disease is limited.

The role of hemodialysis machines dedication in reducing Hepatitis C transmission in the dialysis setting in Iran: a multicenter prospective interventional study.

BACKGROUND: Hepatitis C virus (HCV) infection is a significant problem among patients undergoing maintenance hemodialysis (HD). We conducted a prospective multi-center study to evaluate the effect of dialysis machine separation on the spread of HCV infection. METHODS: Twelve randomly selected dialysis centers in Tehran, Iran were randomly divided into two groups; those using dedicated machines (D) for HCV infected individuals and those using non-dedicated HD machines (ND). 593 HD cases including 51 HCV positive (RT-PCR) cases and 542 HCV negative patients were enrolled in this study. The prevalence of HCV infection in the D group was 10.1% (range: 4.6%- 13.2%) and it was 7.1% (range: 4.2%-16.8%) in the ND group. During the study conduction 5 new HCV positive cases and 169 new HCV negative cases were added. In the D group, PCR positive patients were dialyzed on dedicated machines. In the ND group all patients shared the same machines. RESULTS: In the first follow-up period, the incidence of HCV infection was 1.6% and 4.7% in the D and ND group respectively (p = 0.05). In the second follow-up period, the incidence of HCV infection was 1.3% in the D group and 5.7% in the ND group (p < 0.05). CONCLUSIONS: In this study the incidence of HCV in HD patients decreased by the use of dedicated HD machines for HCV infected patients. Additional studies may help to clarify the role of machine dedication in conjunction with application of universal precautions in reducing HCV transmission.

Laser hair removal: comparison of long-pulsed Nd:YAG, long-pulsed alexandrite, and long-pulsed diode lasers.

BACKGROUND: Advances in laser technology over the past several years have led to the development of numerous lasers for the treatment of unwanted hair. Laser wavelength is a key factor influencing treatment efficacy and complication rates. OBJECTIVE: To compare the efficacy and safety of laser hair removal using three different laser systems. METHODS: A retrospective study of 805 consecutive laser-assisted hair removal treatments, conducted on 75 patients by means of either a long-pulsed Nd:YAG, a long-pulsed alexandrite, or a long-pulsed diode laser is reported. All patients were evaluated at least 3 months after the last treatment, and their present conditions were compared with the 1st-day photographs. RESULTS: The mean hair reduction was 42.4%, 65.6%, and 46.9% in Nd:YAG, alexandrite, and diode lasers, respectively. When the number of treatment sessions was taken into account, the efficacy of alexandrite and diode lasers was not significantly different, whereas both systems were more efficacious than Nd:YAG. Neither of the laser systems showed better results for a particular skin type. The occurrence of side effects was not significantly different between three laser systems. CONCLUSION: Both long-pulsed alexandrite and long-pulsed diode laser systems are effective in the treatment of unwanted hair, and they are more efficacious than Nd:YAG laser.