John Koo

University of California, San Francisco, San Francisco, California, United States

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Publications (173)489.28 Total impact

  • New England Journal of Medicine 10/2015; 373(14):1318-1328. DOI:10.1056/NEJMoa1503824 · 55.87 Impact Factor
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    ABSTRACT: A common therapeutic modality for psoriasis includes the combination of phototherapy with topical treatments. The recent development of targeted phototherapy with the excimer laser and spray formulations for topical treatments has increased the efficacy and convenience of these combinational therapies. Herein, we aim to assess the efficacy of a novel combination of therapies using the 308-nm excimer laser, clobetasol propionate spray and calcitriol ointment for the treatment of moderate to severe generalized psoriasis. In this 12-week study, patients with moderate to severe psoriasis received twice weekly treatments with a 308-nm excimer laser combined with clobetasol proprionate twice daily for a month followed by calcitriol ointment twice daily for the next month. Of the 30 patients enrolled, 83% of patients (25/30) achieved PASI-75 (65%-94%, 95% confidence interval) at week 12. For PGA, there was an estimated decrease of 3.6 points (3.1 to 4.1, 95% CI, p<0.0005) by week 12. In conclusion, the combination of excimer laser with alternating clobetasol and calcitriol application has shown to be a promising combination of therapies for treatment of moderate to severe generalized psoriasis. Further evaluation may be conducted with a larger study inclusive of control groups and head-to-head comparisons against topical steroid and UVB therapy as monotherapies.
    Journal of Dermatological Treatment 09/2015; DOI:10.3109/09546634.2015.1088640 · 1.67 Impact Factor
  • Rachel McAndrew · Ethan Levin · John Koo
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    ABSTRACT: Increased knowledge of the molecular regulatory mechanisms that contribute to the pathogenesis of psoriasis and other inflammatory diseases has created new opportunities for the development of targeted drug therapy for inflammatory conditions. Two new oral medications, apremilast and tofacitinib, have been developed for their immunomodulatory properties, and their potential efficacy in treating psoriasis is being evaluated. We reviewed phase III randomized, placebo-controlled clinical trial results for apremilast and tofacitinib for efficacy and safety in psoriasis. Psoriasis Area and Severity Index (PASI) 75 after 16 weeks for apremilast was between 28.8% and 33.1%. PASI 75 was 39.5% after 12 weeks on tofacitinib 5 mg, and 63.6% after 12 weeks on tofacitinib 10 mg. Common side effects for both drugs included nasopharyngitis and upper respiratory tract infections. Gastrointestinal disturbance was common for apremilast. Dyslipidemia and infections were more common with tofacitinib than placebo. Both new oral medications, apremilast and tofacitinib, appear to be effective in treating psoriasis. J Drugs Dermatol. 2015;14(8):786-792.
    Journal of drugs in dermatology: JDD 08/2015; 14(8):786-92. · 1.45 Impact Factor
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    ABSTRACT: Psoriasis is a chronic immune-mediated inflammatory condition that affects 2-3% of the population. Apremilast was FDA-approved in March 2014 for the treatment of psoriatic arthritis and in September 2014 for the treatment of moderate to severe plaque psoriasis. Apremilast appears to have lower efficacy than some biologic agents such as adalimumab and ustekinumab, which achieve a PASI-75 in approximately 70% of patients after 12-16 weeks of therapy. However, its ease of administration as an oral agent coupled with a mild side effect profile make it an attractive option for psoriasis treatment. Herein, we present a patient with a 17-year history of plaque type psoriasis recalcitrant to topical, oral, and biologic mediations who attained near-complete remission after therapy with a combination of adalimumab and apremilast.
    Dermatology online journal 07/2015; 21(6).
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    ABSTRACT: Phototherapy is an effective treatment for several inflammatory skin conditions. While its utility is well-recognized (e.g. 45% of American Academy of Dermatology members prefer phototherapy as a first-line psoriasis treatment) [1] its use has significantly declined in the U.S. [2, 3] Part of the problem may be the training of residents. A survey conducted in 1994, which included 66 dermatology chief residents, found that over 50% of respondents received fewer than 3 hours of phototherapy training annually, and 55% reported no hands-on tutorials. [4] Many residents felt ill-prepared to provide phototherapy. Based on a similar study surveying dermatology residents, our results indicate that 20 years later, phototherapy training remains lacking. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Photodermatology Photoimmunology and Photomedicine 05/2015; 31(5). DOI:10.1111/phpp.12182 · 1.26 Impact Factor
  • Eric Sorenson · John Koo
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    ABSTRACT: Biologic agents have greatly enhanced the treatment of moderate-to-severe plaque psoriasis. Previous reviews of the safety of biologic agents have included patients with conditions other than psoriasis and/or have not used statistical significance as the primary analytic focus. Our aim was to review the current literature to identify significantly increased adverse events associated with the use of etanercept, adlimumab and ustekinumab for the treatment of moderate-to-severe plaque psoriasis. We performed a search of Ovid MEDLINE and the Cochrane Library to identify clinical trials, open-label extension studies and meta-analyses reporting statistical analysis of adverse events associated with the use of etanercept, adlimumab and ustekinumab for the treatment of moderate-to-severe plaque psoriasis. We identified 17 clinical trials, 2 open-label extension studies and 8 meta-analyses. Adverse events reported to be significantly increased included squamous cell carcinoma (SCC), injection-site reaction, and headache associated with etanercept, overall nonmelanoma skin cancer (NMSC), SCC, and upper respiratory tract infection associated with adalimumab, and no significantly increased adverse events associated with ustekinumab. Current evidence suggests that when analyzed among patients with plaque psoriasis, few adverse effects of the biologic agents etanercept, adalimumab and ustekinumab have reached statistical significance. Further long-term studies conducting analysis of statistical significance should be performed.
    Journal of Dermatological Treatment 04/2015; DOI:10.3109/09546634.2015.1027167 · 1.67 Impact Factor
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    ABSTRACT: Psoriasis is a chronic immune disorder that affects 2-3% of the US population. Ustekinumab, a monoclonal antibody against IL-23/12, has shown great efficacy in treating psoriasis. Here we present a rare finding of a patient with plaque-type psoriasis who was diagnosed with congestive heart failure after initiating treatment with ustekinumab. The patient experienced full recovery of cardiac function upon discontinuation of ustekinumab.
    04/2015; 19(2). DOI:10.1016/j.jdds.2015.03.003
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    ABSTRACT: Chronic graft-vs-host disease (GVHD) affects 50% to 70% of patients who receive allogeneic hematopoietic cell transplants (HCTs), and the skin is the most common site of involvement. Chronic cutaneous GVHD can present with sclerotic or nonsclerotic changes of the skin and often requires treatment with systemic immunosuppressants, extracorporeal photopheresis, or phototherapy. We describe the first reported case, to our knowledge, of the effective treatment of sclerotic chronic cutaneous GVHD with narrowband UV-B (NB UV-B) phototherapy. A woman in her 40s presented with sclerotic chronic GVHD of the skin 6 years after HCT for treatment of chronic myelogenous leukemia. The patient's cutaneous disease progressed despite treatment with prednisone and oral tacrolimus. The patient was initiated on NB UV-B phototherapy 3 times per week, resulting in clinically significant improvement of cutaneous lesions over the first 2 months. The NB UV-B regimen allowed for a reduction of prednisone dose and continued control of cutaneous GVHD over 6 months of therapy. Our case report describes the successful use of NB UV-B phototherapy for the treatment of sclerotic chronic cutaneous GVHD. Further study should be performed to evaluate the effectiveness of this therapeutic modality for patients with sclerotic chronic cutaneous GVHD.
    JAMA Dermatology 03/2015; DOI:10.1001/jamadermatol.2015.0175 · 4.43 Impact Factor
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    ABSTRACT: Effective treatments for moderate to severe psoriasis are phototherapy and biologics. These treatments are similar in that they both decrease cutaneous immune system hyperactivity yet do so via different mechanisms. Our patient, a 63 year old Asian male had a rapid response to treatment with the high dose excimer laser, having previously failed treatment with 28 weeks of ustekinumab therapy. A pre-treatment biopsy of a psoriatic plaque was found to contain relatively low levels of IFN-γ (Th1) and IL-17 (Th17) secreting T cells. Following treatment with the excimer laser, the patient had a quick improvement in PASI that was reflected by a 3-fold reduction in the number of live T cells found in the post-treatment biopsy. Although ustekinumab and the excimer laser both result in decreased levels of these cytokines, the excimer laser directly causes apoptosis of T cells and induces DNA damage in antigen presenting cells. Thus, the broader effects of phototherapy on immune cells compared to the targeted inhibition of IL-12 and IL-23 by ustekinumab likely account for the superior response observed.
    Dermatology online journal 03/2015; 21(3).
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    ABSTRACT: Psychodermatology is an underappreciated field that studies psychocutaneous disorders, which are conditions that have both dermatologic and psychiatric characteristics. Underlying psychiatric comorbidity is estimated to occur in up to one-third of dermatologic patients, and psychiatric illness may either be the cause or the consequence of dermatologic disease. Psychodermatologic patients lack insight and often do not recognize a psychiatric etiology for their symptoms and therefore comprise some of the most challenging cases to treat. Herein, we discuss the background and clinical presentation of the most commonly encountered psychodermatologic conditions, including delusional infestation, neurotic excoriations, factitial dermatitis, trichotillomania and body dysmorphic disorder, followed by practical diagnostic and therapeutic recommendations. © 2015 S. Karger AG, Basel.
    Advances in psychosomatic medicine 03/2015; 34:123-34. DOI:10.1159/000369090
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    Journal of the American Academy of Dermatology 01/2015; 72(1):e40-2. DOI:10.1016/j.jaad.2014.09.050 · 4.45 Impact Factor
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    ABSTRACT: Patient satisfaction is an important component of dermatological care that reflects patients' perspectives on the care they receive. While physicians' expertise and judgment should always remain the foundation of providing appropriate and effective care, the patient experience can also be influenced by interpersonal relationships, expectations, and a sense of agency in the treatment patients receive. Dermatology providers can use practical techniques such as sitting rather than standing, reframing the concept of cure, and engaging patients in treatment decisions to improve the patient-provider experience and thereby optimize patient satisfaction.
    American Journal of Clinical Dermatology 01/2015; 16(1). DOI:10.1007/s40257-014-0111-7 · 2.73 Impact Factor
  • Viraat Patel · John Y M Koo
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    ABSTRACT: Abstract Delusions of parasitosis (DoP) is a psychocutaneous condition characterized by a fixed false belief that one is infested by skin parasites. Patients afflicted with DoP generally experience sensations of biting, stinging, or crawling in the absence of any objective evidence of infestation. The most definitive treatment for delusions of parasitosis is antipsychotic agents. Though the diagnosis and treatment options are rather straightforward, the difficulty lies in the art of building a therapeutic rapport with the patient in order to encourage acceptance of antipsychotic treatment. This article is a practical guide that suggests verbatim how dermatologists might talk to a delusional patient in order to establish a strong therapeutic rapport. Strategies on how to optimize the initial encounter, build rapport, and prescribe antipsychotic medications that are likely to be accepted by the patient are discussed.
    Journal of Dermatological Treatment 12/2014; 26(5):1-15. DOI:10.3109/09546634.2014.996513 · 1.67 Impact Factor
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    ABSTRACT: Patient satisfaction has been and is of growing importance in healthcare. Recent healthcare initiatives aim to provide physicians with performance feedback reports based partially on patient completed surveys; thus, patient satisfaction will be an even more important determinant of high quality care. In the field of dermatology, patient satisfaction is particularly relevant and at times difficult to achieve, since many patients are plagued with chronic skin diseases often requiring intensive topical regimens or undesirable systemic immunosuppressants. The discussion of patient satisfaction is usually restricted to encounters with the general clinic population leaving encounters with difficult patients largely underreported; therefore, we provide examples of more common difficult patient encounters a dermatologist may face with specific recommendations on how to best optimize patient satisfaction.
    Clinics in Dermatology 09/2014; 32(5). DOI:10.1016/j.clindermatol.2014.01.001 · 2.47 Impact Factor
  • Eva Wang · John Koo · Elie Levy
    Journal of the American Academy of Dermatology 08/2014; 71(2):391–393. DOI:10.1016/j.jaad.2014.03.046 · 4.45 Impact Factor
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    ABSTRACT: Phototherapy is often used to treat inflammatory skin conditions such as psoriasis and eczema. Much progress has recently been made in understanding the mechanisms underlying the local, cutaneous immune effects induced by phototherapy. Unlike many immunosuppressive drugs used in the management of inflammatory skin disease, phototherapy not only targets effector immune cells but also appears to up-regulate regulatory T cells (Tregs). Additionally, phototherapy reverses epidermal barrier abnormalities common in these diseases, allowing for restoration of cutaneous homeostasis. J Drugs Dermatol. 2014;13(5):564-568.
    Journal of drugs in dermatology: JDD 05/2014; 13(5):564-8. · 1.45 Impact Factor
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    ABSTRACT: Patients with psoriasis have been shown to have a higher prevalence of other autoimmune diseases including celiac disease, a condition marked by sensitivity to dietary gluten. A number of studies suggest that psoriasis and celiac disease share common genetic and inflammatory pathways. Here we review the epidemiologic association between psoriasis and celiac disease and perform a meta-analysis to determine whether patients with psoriasis more frequently harbor serologic markers of celiac disease. We also examine whether a gluten-free diet can improve psoriatic skin disease.
    Journal of the American Academy of Dermatology 04/2014; 71(2). DOI:10.1016/j.jaad.2014.03.017 · 4.45 Impact Factor
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    ABSTRACT: Patients with psoriasis are increasingly turning to the use of alternative and complementary medicine to manage their psoriasis. Patients often inquire about what dietary supplements may be beneficial, including the use of oral vitamin D, vitamin B12, selenium, and omega-3 fatty acids in fish oils. In this review we examine the extent to which each of these common nutritional interventions has been studied for the treatment of psoriasis. We weighed evidence from both controlled and uncontrolled prospective trials. The evidence of benefit was highest for fish oils. For other supplements, there is need for additional large, randomized clinical trials to establish evidence of efficacy.
    Journal of the American Academy of Dermatology 04/2014; 71(3). DOI:10.1016/j.jaad.2014.03.016 · 4.45 Impact Factor
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    ABSTRACT: One of the most frequently asked questions by patients with psoriasis is whether dietary changes can improve their condition. Included in this discussion is whether dietary weight loss can benefit their skin disease. Obesity has been associated with a proinflammatory state and several studies have demonstrated a relationship between body mass index and psoriasis severity. However, the question of whether weight loss interventions can impact psoriasis outcome is less clear. Here, we review the literature to examine the efficacy of weight loss interventions, both dietary and surgical, on psoriasis disease course.
    Journal of the American Academy of Dermatology 04/2014; 71(1). DOI:10.1016/j.jaad.2014.02.012 · 4.45 Impact Factor
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    ABSTRACT: The efficacy of biologic therapy in treating plaque-type psoriasis is well documented. However, there is less data for use in other psoriasis subtypes, such as erythrodermic and generalized pustular psoriasis. We sought to review the safety and efficacy of biologic medications in the treatment of these severe subtypes of psoriasis and to identify strategies to help clinicians optimally manage these patients. We searched Pubmed for English language literature that assessed the use of biologic medication to treat erythrodermic or generalized pustular psoriasis. The primary literature included cases reports, cases series, and open-label, uncontrolled trials. There were no head-to-head studies or other controlled trials. In both erythrodermic and generalized pustular psoriasis, infliximab was used to treat over half of the reported cases. Other biologic medications that were successfully used included etanercept, ustekinumab, adalimumab, and anakinra. Most cases reported improvement with biologic therapy. Serious adverse events were reported in 10-12% of the patients. Although the evidence is limited, biologic therapy appears to be effective in treating erythrodermic and generalized pustular psoriasis. In order to assess the comparative efficacy and safety of the biologic medications, larger controlled studies are needed. J Drugs Dermatol. 2014;13(3):342-354.
    Journal of drugs in dermatology: JDD 03/2014; 13(3):342-54. · 1.45 Impact Factor

Publication Stats

4k Citations
489.28 Total Impact Points


  • 1997–2015
    • University of California, San Francisco
      • Department of Dermatology
      San Francisco, California, United States
  • 2006–2013
    • University of Southern California
      • Keck School of Medicine
      Los Angeles, California, United States
  • 2012
    • University of San Francisco
      San Francisco, California, United States
    • Kaiser Permanente
      Oakland, California, United States
    • University of Utah
      Salt Lake City, Utah, United States
  • 2004–2012
    • CSU Mentor
      Long Beach, California, United States
    • University of Texas MD Anderson Cancer Center
      Houston, Texas, United States
  • 2011
    • University of Illinois at Chicago
      Chicago, Illinois, United States
  • 2005–2011
    • University of California, Irvine
      • • Department of Pediatrics
      • • Department of Dermatology
      Irvine, California, United States
    • Oregon Health and Science University
      • Department of Medicine
      Portland, Oregon, United States
    • California State University, Sacramento
      Sacramento, California, United States
  • 1993–2011
    • San Francisco VA Medical Center
      San Francisco, California, United States
  • 2010
    • Geisel School of Medicine at Dartmouth
      Hanover, New Hampshire, United States
  • 2005–2010
    • University of Pittsburgh
      • Department of Dermatology
      Pittsburgh, Pennsylvania, United States
  • 2003
    • University of Texas at Dallas
      Richardson, Texas, United States
  • 1999
    • Icahn School of Medicine at Mount Sinai
      • Department of Dermatology
      Borough of Manhattan, New York, United States