Efficacy of narrow band UVB with or without OMP in stabilization of vitiligo activity in skin photo-types (III-V): A double-blind, randomized, placebo-controlled, prospective, multicenter study.

BACKGROUND: NB-UVB has long been the vitiligo management pillar with capability of achieving the main treatment outcomes; repigmentation and stabilization. Its stabilizing effect in dark skin has been debatable. However, randomized controlled trials regarding NB-UVB ability to control disease activity are lacking. PURPOSE: To assess stabilizing effect of NB-UVB in comparison to systemic corticosteroids, the mainstay in vitiligo stabilization, in skin photo-types (III-V). METHODS: This is a multicenter, placebo-controlled, randomized, prospective study. Eighty patients with active nonsegmental vitiligo (NSV) (Vitiligo disease activity (VIDA) ≥2) were randomized to either NB-UVB and placebo (NB-placebo) or NB-UVB and dexamethasone oral mini-pulse (OMP) therapy (NB-OMP) for 6 months. Sixty four patients completed the study, 34 in the NB-OMP group and 30 in the NB-placebo group. Patients were evaluated fortnightly according to presence or absence of symptoms/signs of activity. RESULTS: In spite of earlier control of disease activity observed in the NB-OMP group, it was comparable in both groups by the end of the study period. Disease activity prior to therapy, but not extent, was found to influence control of activity in both groups. Thus, NB-UVB is a safe sole therapeutic tool in vitiligo management. Not only does it efficiently achieve repigmentation, but also it is a comparable stabilizing tool for systemic corticosteroids in spite of slightly delayed control. CONCLUSION: NB-UVB is the only well-established vitiligo therapy that can be used solely whenever corticosteroids are contraindicated or immune-suppression is unjustified. Nonetheless, its combination with corticosteroids expedites response and improves compliance.

Fractional Erbium-Doped Yttrium Aluminum Garnet Laser in the Treatment of Primary Cutaneous Amyloidosis.

BACKGROUND: Although various treatments are currently available for primary cutaneous amyloidosis (PCA), there is no entirely satisfactory treatment. Recently, fractional ablative lasers are claimed to have therapeutic effects for PCA. OBJECTIVE: To evaluate the efficacy and safety of fractional Er:YAG laser for the treatment of PCA. METHODS AND MATERIALS: Ten patients with macular and lichen amyloidosis received 4 treatment sessions with 4-week intervals. The outcome was assessed clinically (degree of pigmentation, rippling, lichenification, and itching) through photographs and histologically (amount of amyloid, melanin, epidermal thickness, and depth of rete ridges) through biopsy specimens stained with hematoxylin-eosin, Congo red, and Fontana-Masson stain. Patients were followed up for 3 months after the final treatment. RESULTS: At 3-month follow-up, fractional Er:YAG laser exhibited a significant clinical and histological improvement. Patient satisfaction concurred with physicians' evaluations. Recurrence was detected in 1 patient. CONCLUSION: In light of the authors' findings, fractional Er:YAG laser offered a great clinical and histological efficacy with excellent safety profile. Careful laser selection based on making a compromise between efficacies and safeties may improve outcome.

Estimation of Homocysteine Level and Methylenetetrahydrofolate Reductase (MTHFR) Gene and Cystathionine B Synthase (CBS) Gene Polymorphisms in Vitiligo Patients.

BACKGROUND: Vitiligo is an acquired, multifactorial disorder of the skin and mucous membranes. An elevated homocysteine level has been described in vitiligo. Methylenetetrahydrofolate reductase (MTHFR) and cystathionine B synthase (CBS) are major determinants of the homocysteine metabolism. OBJECTIVES: Determine serum homocysteine levels in vitiligo patients as well as the association between MTHFR (C677T, A1298C) and CBSgene polymorphisms and susceptibility to vitiligo in a sample of those populations. METHODS: Homocysteine levels were estimated by radioimmunoassay while MTHFR (C677T, A1298C) and CBSgene polymorphisms were detected by the polymerase chain reaction-restriction fragment length polymorphism technique in 100 vitiligo patients and 80 healthy controls. RESULTS: The homocysteine level was significantly higher in vitiligo patients than controls (p = 0.000). Significant differences in the genotype and allele distributions of single nucleotide polymorphisms of the MTHFR (C677T, A1298C) with the mutant genotypes are more common in the controls than patients (p = 0.001, 0.029, respectively). CBS gene mutant genotypes and alleles are more common in vitiligo patients than controls (p = 0.002). CONCLUSION: CBSand MTHFRgene polymorphisms may play a major role in the genetic susceptibility to vitiligo.

Fractional Erbium-Doped Yttrium Aluminum Garnet Laser Versus Microneedling in Treatment of Atrophic Acne Scars: A Randomized Split-Face Clinical Study.

BACKGROUND: Ablative fractional erbium-doped yttrium aluminum garnet (Er:YAG) laser and microneedling have been popularized in recent years and their effectiveness and side effects individually reported. No previous study, however, has directly compared the efficacy and safety between the 2 different treatments. OBJECTIVE: To compare the efficacy and safety of the ablative fractional Er:YAG laser and microneedling for the treatment of atrophic acne scars. MATERIALS AND METHODS: Thirty patients with atrophic acne scars were randomly treated in a split-face manner with a fractional Er:YAG laser on one side and microneedling on the other side. All patients received 5 treatments with a 1-month interval. Objective and subjective assessments were obtained at baseline and at 3 months after the final treatment. RESULTS: At the 3-month follow-up, both treatment modalities induced noticeable clinical and histological improvement, with significantly better results in fractional Er:YAG laser versus microneedling (70% vs 30%), respectively (p < .001). Fractional Er:YAG laser sides had significantly lower pain scores. Total downtime was significantly shorter in microneedling sides. CONCLUSION: Both treatment modalities are effective and safe in the treatment of atrophic acne scars, with significantly higher scar response to the fractional Er:YAG laser treatment.

Vitiligo - The story from within: A transmission electron microscopic study before and after narrow-band ultraviolet B.

Melanocyte loss is the main feature of vitiligo, but evidence refers to pathological multiplayers. Transmission electron microscopy was utilized to further explore vitiligo before and after narrow-band ultraviolet B (NB-UVB) therapy. Skin biopsies were retrieved from lesional and perilesional skin and compared to normal control skin. Sections were examined for melanocytes and keratinocytes and the number of melanosomes and thickness of basal lamina were measured. In lesional skin, keratinocytes revealed two types of degeneration with a significant increase in the mean thickness of basal lamina and decrease in the number of melanosomes. After treatment, lesional and perilesional skin showed variable ultrastructural features.

Comparison of the effectiveness of two fluences using long-pulsed Nd:YAG laser in the treatment of striae distensae. Histological and morphometric evaluation.

Striae distensae are common undesirable skin lesions of significant aesthetic concern. To compare the efficacy of two fluences (75 and 100 J/cm2) of long-pulsed Nd:YAG laser in the treatment of striae. Forty-five patients (Fitzpatrick skin types III-V) aged between 11 and 36 years with striae (23 patients with rubra type and 22 with alba type) were enrolled in the study. Each stria was divided into three equal sections, whereby the outer sections were treated with long-pulsed 1064 nm Nd:YAG laser, at a fluence of 75 or 100 J/cm2, and fixed laser settings of 5 mm spot size and 15 ms pulse duration. The middle section was an untreated control. All subjects received four treatments at 3 weeks interval. Three 2-mm punch biopsies were taken from six subjects, all of the same stria, one before treatment and the other two from the outer sections, 3 months after the last session. Paraffin-embedded skin sections were subjected to histological and quantitative morphometric studies for collagen and elastic fibres. Results were assessed clinically through photographic evaluation and were considered satisfactory for both doctors and patients. A significant improvement in appearance of striae alba using 100 J/cm2 was found while striae rubra improved more with 75 J/cm2. Histologically, collagen and elastin fibres increased in posttreatment samples. A satisfactory improvement in striae distensae lesions was seen through clinical and histological evaluation. Thus, long-pulsed Nd:YAG laser is a safe and effective module of laser treatment for these common skin lesions.

T helper 17 and Tregs: a novel proposed mechanism for NB-UVB in vitiligo.

Narrowband ultraviolet (NB-UV)B is accepted as corner stone therapy for vitiligo. Its influence on the expression of IL-17, IL- 22 and FoxP3 as markers for the Th17 and Tregs lineages has not been studied before in the context of non-segmental vitiligo (NSV). The study included 20 active NSV patients who received 36 NB-UVB sessions and 20 controls. Clinical evaluation Vitiligo Area Scoring Index (VASI) and determination of tissue expression of IL-17, IL-22 and FoxP3 by qRT-PCR (lesional, perilesional) were carried out before and after therapy. Baseline levels of IL-17 and IL-22 were significantly higher in patients, whereas FoxP3 was significantly lower. After therapy, IL-17 and IL-22 significantly dropped, whereas FoxP3 significantly increased (lesional, perilesional). Baseline and post-treatment VASI showed significant positive correlations with IL-17 and IL-22 and significant negative correlation with FoxP3 expression. Restoration of the balance between Th17 and Tregs might represent a novel pathway for the improvement that NB-UVB exerts in vitiligo patients.

Randomized split-face controlled study to evaluate 1550-nm fractionated erbium glass laser for treatment of acne vulgaris--an image analysis evaluation.

BACKGROUND: Novel and promising results in acne treatment with infrared lasers have been reported. The 1,550-nm erbium glass laser is one of the infrared lasers that may be useful in the treatment of acne. OBJECTIVE: The aim of this study was to evaluate the efficacy of an erbium glass laser in treatment of active acne and to study the effect of this type of laser on sebaceous glands. PATIENTS AND METHODS: Twenty-four patients with active acne lesions were treated using 1,550-nm (30-40 mJ) fractional erbium glass laser. Every patient received 4 sessions with a 2-week interval. Follow-up was done every 3 months for 1 year. The image analyzer computer system was used to measure the sebaceous gland size. RESULTS: A significant reduction (p < .0001) in the mean count of lesions was observed after treatment and in the follow-up period. A significant reduction in the size of sebaceous glands was also evident after laser treatment. CONCLUSION: Treatment of active acne with the 1,550-nm erbium glass laser is effective. Papules, pustules, and nodules all respond well to therapy. The sebaceous gland size decreased significantly, which accounts for the long remission period.

Autologous platelet rich plasma: topical versus intradermal after fractional ablative carbon dioxide laser treatment of atrophic acne scars.

BACKGROUND: A proposal has recently been made regarding the potential adjuvant use of platelet-rich plasma (PRP) with fractional carbon dioxide laser (FCL) for the correction of acne scars. OBJECTIVE: To compare the efficacy and safety of two administration modes of autologous PRP (intradermal injection (ID) and topical application) after FCL with that of FCL alone in the treatment of atrophic acne scars. PATIENTS AND METHODS: Thirty patients were randomly divided into two groups. Both underwent split-face therapy. Group 1 was administered FCL followed by ID PRP on one side and FCL followed by ID saline on the other. In group 2, one cheek was treated with FCL followed by ID PRP, and the other received FCL followed by topical PRP. Each patient received 3 monthly sessions. The final assessment took place at 6 months. RESULTS: Combined PRP- and FCL-treated areas had a significantly better response (p = .03), fewer side effects, and shorter downtime (p = .02) than FCL-treated areas, but there were no significant differences in ID- and topical PRP-treated areas in degree of response and downtime (p = .10); topically treated areas had significantly lower pain scores. CONCLUSION: The current study introduces the combination of topical PRP and FCL as an effective, safe modality in the treatment of atrophic acne scars with shorter downtime than FCL alone and better tolerability than FCL combined with ID PRP.

Hypopigmented parapsoriasis en plaque, a new, overlooked member of the parapsoriasis family: a report of 34 patients and a 7-year experience.

BACKGROUND: In the past 7 years we have extensively studied an uncommon hypopigmented disorder that, apart from hypopigmentation, showed many common features with parapsoriasis en plaque (PSEP), both clinically and histopathologically. OBJECTIVE: We sought to verify whether this disorder should be considered a hypopigmented variant of PSEP and thus be referred to as hypopigmented PSEP. METHODS: A total of 34 patients presenting with this peculiar hypopigmented disorder were included (2003-2010). Patients were subjected to a predesigned algorithm excluding all possible differential diagnoses of hypopigmented lesions. RESULTS: Our findings indicated that this disorder can be diagnosed as hypopigmented PSEP. These findings included: (1) exclusion of all other disorders causing similar hypopigmented lesions; (2) shape and size of the lesions being very similar to those of classic small PSEP (small-plaque parapsoriasis [SPP]); (3) similar distribution of the lesions (trunk, proximal upper and lower limbs) to the classic PSEP; (4) digitiform extensions of most the lesions (70.5% of our patients) as in SPP; (5) absence of itching as in PSEP (SPP type); (6) good response to narrowband ultraviolet B in 76.4% of the patients (n = 26); and (7) during follow-up 5 patients (14.7%) converted into hypopigmentd mycosis fungoides. LIMITATIONS: A limitation in our study is that we did not perform clonal T-cell receptor gene rearrangement because of limited resources. CONCLUSION: Based on our findings we believe that this hypopigmented disorder is a well-defined new variant of the PSEP family that shows, apart from the hypopigmentation, all the features of PSEP, particularly the SPP variant, and accordingly could be referred to as hypopigmented PSEP.

Broad band UVA: a possible reliable alternative to PUVA in the treatment of early-stage mycosis fungoides.

UVA1 phototherapy was found to induce marked improvement in skin lesions of patients with stages IA and IB mycosis fungoides (MF). Broad band UVA (BB-UVA) is composed of 80.1% UVA1, with similar mechanisms of action. Our aim was to evaluate the efficacy of BB-UVA in the treatment of early-stage MF. Thirty patients with early stage MF were included. They were divided into two equal groups receiving either BB-UVA at 20 J/cm2/ session or PUVA three times/week for 40 sessions. Clinical and histopathological evaluations were performed before and after therapy in addition to immunohistochemical measurement of CD4+ cells and Bcl-2. Patients were followed up for an average duration of 36 months. Comparable clinical and histopathological improvement was noted in MF patients in both groups. Clinical improvement graded 'Excellent' was achieved in 33% of patients in the BB-UVA versus 13.3% in the psoralen and UVA (PUVA) group. Long-term follow-up indicated superiority of BB-UVA over PUVA. BB-UVA group showed a more rapid clearance rate, shorter time to achieve complete clearance, a longer disease-free interval and lower relapse rate. The use of BB-UVA in the treatment of early-stage MF is comparable or even superior to PUVA regarding efficacy and remission periods.

Platelet-rich plasma versus carboxytherapy in the treatment of periorbital dark circles: A split-face study.

BACKGROUND: Periorbital hyperpigmentation is a recurrent problem in dermatologic clinics that affect the patients' quality of life and their psychological status. Platelet-rich plasma (PRP) may serve as a source of different growth factors which may reduce the pigmentation in this problem. Carboxytherapy is carbon dioxide infusion into human tissue for therapeutic purposes. OBJECTIVE: To evaluate and compare the clinical efficacy of PRP and carboxytherapy in the treatment of periorbital dark circles (PODC). Histopathological evaluation was also done. PATIENTS AND METHODS: Split-face study of 23 patients with PODC treated with PRP at the right side and carboxytherapy at the left side. Patients received four sessions; one session/week. Final follow-up evaluation was done 3 months after the last session by clinical and histopathological assessment. RESULTS: PRP showed significant better response (p = 0.002), shorter downtime, and tolerable side effects than caboxytherapy. Reduction in area percent of melanin after PRP injections showed 46.6% improvement, while after carboxytherapy, it showed only 14.3% improvement. CONCLUSION: The present study showed that PRP is more effective and tolerable than caboxytherapy in the treatment of PODC.

Trichoscopy as an evaluation method for alopecia areata treatment: A comparative study.

BACKGROUND: Trichoscopy is a useful tool for diagnosis and follow-up of alopecia areata (AA) patients. Both platelet-rich plasma (PRP) and intralesional corticosteroids (ILCs) are important treatment modalities of patchy AA. AIM: Trichoscopic diagnosis of AA and monitoring the treatment response to PRP versus ILCs in patchy AA treatment. PATIENTS/METHODS: This comparative study included 31 patients with patchy AA, divided into two groups: (group A) received ILCs while (group B) received PRP once monthly for 3 months. Evaluation was done by Severity of Alopecia Tool (SALT) score, Alopecia Areata Symptom Impact Scale (AASIS), photography, and dermoscopy. RESULTS: There was a significant improvement in trichoscopic findings in both groups with regard to the number of follicular units per opening, black dots, broken hairs, and dystrophic changes. Final SALT score showed significant lower levels in both groups compared to baseline levels (P = .025 & P = .008). Final AASIS showed significant decrease in group B (P = .006) not in group A (P = .062). CONCLUSION: Trichoscopy can help in the diagnosis, evaluation of the efficacy and safety of both modalities and might give a clue for treatment response. Both ILCs and PRP were effective in patchy AA treatment.

PUVA-induced pityriasis lichenoides chronica-like papular lesions in patients with mycosis fungoides: a clinical, histopathological and immunohistochemical study.

Mycosis fungoides (MF) is the most common form of cutaneous T cell lymphoma (CTCL) with many clinical variants including papular and pityriasis lichenoides chronica (PLC)-like variants. During psoralen and ultraviolet A (PUVA) treatment of MF, PLC-like papular lesions were observed to appear. The exact nature of these lesions is not fully understood. This work aimed to study PLC-like papular lesions arising in MF patients receiving PUVA therapy clinically, histopathologically and immunohistochemically (using monoclonal antibodies against CD4 and CD8) and to compare them with lesions in classic PLC patients. Fifteen MF patients with PLC-like papular lesions arising during PUVA treatment were included and 15 patients with classic PLC served as controls. While the extent of these lesions significantly correlated with their duration (p < 0.05), it showed no significant correlation with the TNMB stage of MF, number of phototherapy sessions or cumulative UVA dose at which they started to appear. The response status of MF to PUVA did not affect their development. Compared to classic PLC, these lesions showed significantly more acute onset (p = 0.003). None of these lesions showed histopathological features essential to diagnose papular/PLC-like MF and no significant difference existed with regard to their histopathological and CD4/CD8 phenotypic features compared to classic PLC. Papular lesions mimicking PLC in MF patients receiving PUVA mostly represent an upgrading reaction with possible good prognostic implication.

Increased tenascin C and DKK1 in vitiligo: possible role of fibroblasts in acral and non-acral disease.

Recently, multiple culprits-in addition to melanocytes-have been implicated in the pathogenesis of vitiligo. Among those factors are fibroblasts. However, their exact role has not been clearly elucidated. The aim of the study was to evaluate the possible role played by fibroblasts in vitiligo via studying the expression Tenascin C and DKK1 in acral versus non-acral vitiligo lesions. This case-control study included 19 non-segmental vitiligo patients and ten controls. All patients were subjected to thorough clinical evaluation. Both Tenascin C and DKK1 were measured in lesional and peri-lesional skin of acral and non-acral lesions using ELISA technique. The measured levels of Tenascin C and DKK1 were significantly higher in the vitiligo group when compared to controls in all assessed sites (P < 0.05). Tenascin C was found to be significantly higher in lesional areas compared to peri-lesional ones only in the acral sites. DKK1 was significantly higher in lesional areas in all assessed sites (P < 0.05). The current work suggests a malfunction of fibroblasts in vitiligo, through demonstrating significant up-regulation of two melanogenesis inhibitory products (Tenascin C and DKK1) in patients compared to controls. Larger scale studies are warranted to detect the possible implications of such findings on vitiligo treatment.

CXCL-10 and Interleukin-6 are reliable serum markers for vitiligo activity: A multicenter cross-sectional study.

This cross-sectional multicenter study aimed to evaluate serum CXCL-10, as an activity marker for vitiligo, and compare it with other putative serum and tissue markers. Serum CXCL-10 was compared to interferon gamma (IFN-γ), interleukin 6 (IL-6), and IL-17 using ELISA in 55 non-segmental vitiligo patients (30 active and 25 stable) and 30 healthy controls. Marginal skin biopsy was taken for immunohistochemical evaluation of CD8+T cells and CXCL-10+ve cells. Serum levels of CXCL-10, IL-17, and IL-6 were elevated in all vitiligo patients compared to controls (p < .05). All investigated serum markers were higher in active versus stable vitiligo. Tissue expression of CXCL-10+ve cells and CD8+ve T cells was stronger in vitiligo patients compared to controls, and tissue CXCL-10+ve cell expression was stronger in active versus stable cases. Positive correlations were noted between the different serum and tissue markers. CXCL-10 was the most specific, whereas IL-6 was the most sensitive serum marker to distinguish active from stable disease.

B cell activating factor and T-helper 17 cells: possible synergistic culprits in the pathogenesis of Alopecia Areata.

The role of T-helper 17 cells (Th17) and regulatory T-cells (Tregs) in the pathogenesis of alopecia areata (AA) has not been clearly elucidated. B cell activating factor (BAFF) being a regulator of T cell activation could be involved in this pathologic process as well. The current study evaluated the expression of IL-17, IL-22, Foxp3 and BAFF in tissue and sera of AA patients. Forty AA patients and 40 age and sex matched healthy controls were included. Tissue and serum levels of IL-17, IL-22, BAFF as well as serum level of Foxp3 were measured by enzyme-linked immunosorbent assay (ELISA). Immunohistochemical staining was used for assessment of tissue level of Foxp3. Tissue and serum levels of IL-17, tissue levels of IL-22 and BAFF were significantly higher in patients. Serum levels of IL-22, Foxp3 and BAFF were non-significantly higher in patients. Foxp3 immunostaining showed negativity in tissue of patients and controls. A significant positive correlation was found between both tissue levels of IL-17 and BAFF (r = 0.474, P = 0.035) and tissue level of IL-22 and disease duration (r = 0.766, P < 0.001) in AA patients. Th17 cells and BAFF are synergistically involved in the pathogenesis of AA. BAFF represents a promising therapeutic target for such a challenging disease. Defective Tregs number and/or function in AA warrants further studies.

Serum Vitamin D and Vitamin D Receptor Gene Polymorphism in Mycosis Fungoides Patients: A Case Control Study.

BACKGROUND: Vitamin D has been considered a key player in various malignancies including cutaneous cancers. To date, mycosis fungoides (MF) has been the least studied in relation to vitamin D. Furthermore, the vitamin D receptor (VDR) single nucleotide polymorphisms (SNPs) have not been tackled before in the context of MF, despite their incrimination in numerous diseases. AIM OF STUDY: To assess the role of vitamin D in MF by measuring its serum level, and studying VDR SNPs (TaqI, BsmI, FokI) in different stages of MF. PATIENTS AND METHODS: 48 patients with various stages of MF, and 45 healthy controls were included. Complete history, full clinical examination and a five mm punch skin biopsy were performed to all recruited patients. Venous blood samples were withdrawn from both patients and controls to determine the serum vitamin D level and VDR gene polymorphisms. RESULTS: Serum vitamin D level was significantly lower in patients (5.3-33.7 nmol/L)] compared to controls (8.3-90.1 nmol/L)] (P<0.001). A significant difference was observed between patients and controls regarding the FokI polymorphism only, being higher in patients (P = 0.039). Also Vitamin D serum levels differed significantly in patients with FokI genotypes (P = 0.014). No significant correlations were detected between any of the studied parameters and the demographic and clinical data of the included subjects. CONCLUSION: Depressed vitamin D and FokI polymorphism are potentially involved in the context of MF. VDR gene polymorphisms warrant further larger scale investigations to detect the exact genes involved in the pathogenesis of such an enigmatic disease.

Study of T helper 1 and T helper 2 responses in pemphigus vulgaris patients receiving interferon alpha 2a injections in addition to a standard protocol therapy: a randomized controlled trial.

T helper (Th)1 insufficiency was recently found to be related to the pathogenesis of pemphigus vulgaris (PV). Decreased Th1 response was particularly noticed in the early stages of PV. Therefore, administration of interferon alpha in the early stages of aggressive PV may lead to rapid control of the acute stage of the disease. Our aim was to evaluate the role of interferon alpha in the treatment of PV. 30 patients with acute severe PV (>60 % affection) and 30 age and sex-matched healthy subjects were included in this RCT. Patients were randomly divided into two groups (A and B). Group B patients received interferon retard (one subcutaneous injection/week for 4 weeks) in addition to our protocol for the treatment of PV (systemic pulse corticosteroids/cyclophosphamide in combination with sulphasalazine and pentoxifylline) that was administered to all the included patients. IFN-γ and IL-4 were estimated by ELISA before treatment, after 4 weeks and at the end of the study duration (12 weeks). Clinical assessment was done by PAAS on a biweekly basis. All PV patients showed significantly (P < 0.001) elevated levels of IL-4 and significantly (P < 0.001) depressed mean concentration of IFN-γ as compared with healthy controls. Twelve weeks after therapy both groups showed significant improvement in their mean PAAS being more evident and more rapid in group B. IFN-γ was elevated significantly and IL-4 was dropped significantly in group B patients in comparison to group A (P < 0.001). As a conclusion, interferon therapy in severe PV could achieve a more prompt and better clinical response.