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Open Access Publications from the University of California

Dermatology Online Journal

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Dermatology Online Journal is an open-access, refereed publication intended to meet reference and education needs of the international dermatology community since 1995. Dermatology Online Journal is supported by the Department of Dermatology UC Davis, and by the Northern California Veterans Administration.

Volume 22, Issue 6, 2016


Why rifampin (rifampicin) is a key component in the antibiotic treatment of hidradenitis suppurativa: a review of rifampin's effects on bacteria, bacterial biofilms, and the human immune system

Combinations of rifampin and clindamycin or rifampin, metronidazole, and moxifloxcin have been reported as effective treatments for hidradenitis suppurativa (HS) Hurley Stage 1 and Hurley Stage 2.  Clinical trials suggest that for stage 1 and mild stage 2 HS, clindamycin 300 mg twice daily and rifampin 300 mg twice daily for 10 weeks can substantially abate HS in ~80% of cases and remit HS in ~50% of cases.  Another study notes use of rifampin-moxifloxacin-metronidazole given for 6 weeks, dosed as rifampin (10 mg/kg once daily), moxifloxacin (400 mg daily), and metronidazole (500 mg thrice daily) with the metronidazole stopped at week 6.   Rifampin and moxifloxacin were continued if the HS improved and side effects did not occur.  Using this triple antibiotic regimen remission occurred in 100% Hurley Stage 1, 80% Hurly Stage 2, and 16.7 % of Hurley Stage 3 HS.   The author typically gives HS clindamycin 300 mg and rifampin 300 mg, each twice daily, for 10 weeks and assesses if remission has occurred.  If the patient has not achieved remission the author continues the regimen as long as the patient’s clinical status continues to improve without side effects.  The reasons why rifampin is so effective against HS have not been fully defined and might involve rifampin's (1) antibacterial effects (2) effects on bacterial biofilms (3) anti-inflammatory effects (4) effects against granulomas (5) and immunomodulatory effects on neutrophils.  It is notable that rifampin, although not first line, is an effective treatment for Clostridium difficile, a pathogen that arises during treatment with clindamycin.  Thus, rifampin enhances safety when rifampin and clindamycin are combined for the treatment of HS.

Case Report

Incontinentia Pigmenti presenting as a newborn eruption: two case presentations

Linear vesicles or papules in a newborn can be a presenting sign of incontinentia pigmenti (IP). In this report, we present two cases of neonates with cutaneous manifestations of incontinentia pigmenti. In one case, mild peripheral eosinophilia was noted. No extra-cutaneous manifestations were noted otherwise in both cases after complete ophthalmological and neurological evaluations. These cases serve as a reminder for clinicians to consider IP in newborns presenting with linear vesicles or papules.

Yellow hair following sequential application of bacitracin zinc and selenium sulfide: Report of acquired xanthotrichosis and review of yellow hair discoloration

BackgroundAcquired yellow hair (xanthotrichosis) can result from the deposition of pigmented compounds on the hair shaft or from chemical modification of hair pigment and protein molecules.

PurposeA white-haired 77-year-old woman who developed xanthotrichosis of her scalp hair following the sequential application of bacitracin zinc ointment and selenium sulfide 2.5% lotion is described and the causes of yellow hair discoloration are reviewed.

Materials and methodsThe clinical features of a woman with acquired yellow hair discoloration are presented. Using PubMed and Google Scholar, the following terms were searched and relevant citations were assessed: bacitracin zinc, hair discoloration, selenium sulfide, xanthotrichosis, and yellow hair.

ResultsYellow hair was observed on the scalp in areas treated with the following regimen: prior to bedtime, several areas of the scalp were treated with a single application of bacitracin zinc ointment. The next morning, selenium sulfide 2.5% lotion was applied and then rinsed from the scalp during showering. Yellow hair discoloration was apparent in co-treated areas immediately following rinsing; the discoloration gradually faded over 2-5 days with regular shampooing.

ConclusionsAcquired yellow hair shaft discoloration has been reported secondary to multiple etiologies, including environmental and occupational exposures, iatrogenic causes (including topical and systemic drugs) and protein-calorie malnutrition. To this list, we add yellow discoloration of white scalp hair due to application of selenium sulfide following topical use of bacitracin zinc in the affected areas as an unexpected adverse effect that may occur in individuals with white hair.

Case Presentation

Cryptococcal cellulitis on the shin of an immunosuppressed patient

Cryptococcus neoformans is a common fungus found throughout the environment that causes opportunistic disease in immunocompromised individuals. Infection of humans with C neoformans usually manifests as lung disease through inhalation of spores or meningoencephalitis by involvement of the central nervous system. Rarely, dissemination in the form of cutaneous lesions can occur in individuals with long term immunosuppression. We present a patient with C. neoformans manifesting as cellulitis with focal segmental glomerulosclerosis treated with corticosteroids. Because of the mortality associated with disseminated cryptococcosis, early identification, especially of atypical cutaneous presentations is critical from a dermatological perspective.

Myxofibrosarcoma presenting as an exophytic, multi-lobed nodule on the leg

Myxofibrosarcoma may present as a dermal or subcutaneous nodule, often on the extremity of an elderly patient. We present a case of myxofibrosarcoma on the lower leg of a 77-year-old man, which illustrates the deeply infiltrative growth pattern of these tumors, as well as the potential for superficial biopsies to show lower grade histopathologic features than subsequent excision specimens.

Unusual location of median raphe cyst presenting as perianal polyp: a case report

Median raphe cysts (MRC) are uncommon, benign congenital lesions that may present anywhere in the midline between the urinary meatus and the anus, with the shaft of the penis and the glans penis being the most common sites. We report a 52-year-old man with median raphe cyst unusually located in perianal region and treated by surgical excision.

Pyodermatitis vegetans of the vulva

Pyodermatitis vegetans (PV) is a rare inflammatory dermatosis of unknown etiology and difficult diagnosis characterized by vesiculopustular, exudative, and vegetating plaques usually localized in the axillary, genital, and oral region. It bears similarities to pemphigus vegetans but clinical history, histology, and immunofluorescence help confirm the diagnosis. Pyodermatitis vegetans is often associated with an underlying gastrointestinal disorder, especially ulcerative colitis. No standardized treatment plan is available for PV. Its evolution tends to follow the progression of the underlying disorder. We report a patient with vulvar PV with good response to systemic antibiotics and corticosteroids.

Pseudoxanthoma Elasticum: report of a case with a novel gene mutation

Pseudoxanthoma Elasticum (PXE) is a rare autosomal recessive disorder characterized by progressive calcification and fragmentation of elastic fibers in the skin, eyes, and cardiovascular system. PXE is caused by mutations in the ABCC6 gene but the specific pathophysiology of this condition remains unknown. We present a case of a patient who was diagnosed with PXE after experiencing vision loss following minor ocular trauma. Our patient had angioid streaks in her right eye, skin laxity of the bilateral dorsal hands, and yellow papules coalescing on the posterior neck. The diagnosis of PXE was confirmed by histopathological examination. PCR amplification of the patient's ABCC6 gene demonstrated a novel gene mutation that is believed to be pathogenic. Patients with PXE are at an increased risk of visual and potentially life-threatening cardiovascular complications. Early diagnosis provides the patient a greater chance of reducing associated morbidity and mortality

Chronic, severe onychocryptosis successfully treated with nail tube splinting in a 13-year-old girl with multiple prior failed matricectomies

Onychocryptosis, also known as ingrown toenail, is caused by growth of the lateral edge of the nail into the nail fold. This results in inflammation of the invaded tissue. It is a common problem with ~70% of cases occurring in people between the ages of 12-30 years and causes significant discomfort, pain, and restriction in activity [1]. There is no standard treatment for onychocryptosis and numerous methods have been used, from conservative approaches such as proper nail trimming techniques to more invasive surgical procedures. All techniques risk the possibility of damage to the nail apparatus, prolonged healing time, and recurrence of disease.We describe a successful case of bilateral nail tube splinting in a pediatric patient with recurrent, severe onychocryptosis and history of multiple matricectomies.

Segmental lesions along blaschko´s lines in an elderly man

Darier disease (DD) is an autosomal dominant genodermatosis characterized by multiple keratotic and crusted papules over seborrheic areas, along with a variable involvement of oral mucosa, palmoplantar region, and nails. Segmental subtypes (type 1 and 2) are uncommon clinically limited forms of DD that usually present at middle age with few cutaneous lesions following Blaschko´s lines. We report a case of extensive multi segmental DD type 1 that developed in an elderly man, an unusual clinical onset of DD that dermatologists should bear in mind.

An atrophic plaque on the breast six years after breast reconstruction surgery

Necrobiosis lipoidica (NL) is a cutaneous disease entity that typically manifests as atrophic yellow plaques with telangiectasias on the anterior tibial region. Although NL is commonly associated with diabetes mellitus, the role of trauma in disease development is less commonly emphasized. The relationship between NL and the Köbner phenomenon has been established, as a few cases of NL occurring in surgical scars have been reported in the literature. We report the first case of NL occurring in a mastectomy scar on the breast in a non-diabetic female, and explore the relationship between NL, diabetes mellitus, and trauma.

Regorafenib- associated panniculitis

Regorafenib is a second-generation multikinase inhibitor that is approved for the treatment of metastatic colon cancer and advanced gastrointestinal stromal tumors. Hand-foot skin reaction, alopecia, and oral mucositis are well-established side effects of this medication. Herein, we discuss a 60-year-old woman who developed a lobular and septal granulomatous panniculitis after six months of therapy with regorafenib. Biopsy demonstrated focal lobular and septal granulomatous inflammation admixed with septal fibrosis and lobular lymphohistiocytic infiltrate associated with fat necrosis. To our knowledge, regorafenib-induced panniculitis has not been previously described. Increased awareness of this presentation can facilitate more timely diagnosis and treatment.

Morbilliform eruption related to eltrombopag: emerging data on the cutaneous toxicity of thrombopoietin receptor agonists

Eltrombopag is a thrombopoietin mimetic used for the treatment of thrombocytopenia in patients with chronic immune thrombocytopenia, hepatitis C patients undergoing antiviral therapy, and thrombocytopenia secondary to aplastic anemia that is refractory to immunosuppressive therapy. We report a case of a 25-year-old man with a history of aplastic anemia who presented with fever and a monomorphic papular rash. Subsequent labs, biopsy, and clinical course favored drug-induced cutaneous toxicity, with eltrombopag as the likely culprit. Eltrombopag is generally well-tolerated; however, clinicians should be aware of the possibility of dose-independent drug-induced cutaneous toxicity with this medication. This report reviews the mechanism and use of eltrombopag along with a summary of associated adverse cutaneous reactions.


Narrowband UVB-induced iatrogenic polymorphous light eruption: a case and suggestions to overcome this rare complication

Polymorphous light eruption (PMLE) is the most common photodermatosis characterized by pruritic papules and papulovesicles, which appear hours to days following ultraviolet (UV) exposure. Herein, the authors report successful treatment of generalized plaque psoriasis with Goeckerman regimen in a patient despite new onset iatrogenic PMLE following narrowband (NB) UVB therapy. Although further studies are necessary, this case suggests that the co-existence of psoriasis and PMLE should not prevent the use of phototherapy; phototherapy, especially as part of the Goeckerman regimen, remains a valuable treatment option for psoriasis in patients with PMLE.

Photo Vignette

Unusual manifestation of mucosal plasmacytosis mimicking erythema multiforme

Mucosal plasmacytoses constitute a group of idiopathic inflammatory disorders, characterized by a dense infiltrate of plasma cells at the mucocutaneous junction without any recognizable dermatosis or neoplasm. We report an unusual clinical presentation of mucosal plasmacytosis presenting with hemorrhagic crusting of the lips, mimicking erythema multiforme.

A Violaceous Nodule in a Lung-transplant Patient

Posttransplantation lymphoproliferative disorder (PTLD) is a rare complication of solid organ or allogenic bone marrow transplantation. Cases localized to the skin are even rarer, with only around 100 cases recorded in the literature [2]. We present a case of 60 year-old-woman, a lung transplant recipient, who presented with an asymptomatic violaceous nodule on her left medial calf. Histopathology was consistent with PTLD of the B-cell subtype, EBV negative. This case is unique in that it was of the B cell subtype of cutaneous PTLD, which has been less commonly observed than the T cell subtype. In addition, the case was EBV negative, which is rare in B cell cutaneous PTLD. The patient was treated with rituximab 600 mg IV weekly for four weeks and cytomegalovirus immune globulin (Cytogam) 100 mg/kg once, with resolution of the nodule.


Motivating medical students by utilizing dermatology-oriented online quizzes

Background: Online quiz competitions can facilitate extra-classroom interactions between faculty and medical students. Owing to decreased class attendance nationwide, teaching faculty might revamp their approach to medical education by providing online resources and methods for communication.

Objective: To explore if the use of online quizzes and social media can result in improved interactions between faculty and students.

Methods: A pilot study conducted from April 7th, 2015 to June 11th, 2015 at Northeast Ohio Medical University (NEOMED) among participants from the second year medical school class. Ten one-question quizzes created using Google Forms were announced over Twitter and email at the rate of one quiz per week. The first correct responder of each quiz chose a five-dollar coffee shop gift card, movie ticket, or a meeting with a NEOMED faculty person as their prize.

Results: An average of 23.8% of the second year medical student class at NEOMED participated per quiz. A total of 80 individuals (55.9%) submitted 340 responses during the competition.Limitations: This is a single-center study with a limited sample size.

Conclusions and Relevance: This study presents a process evaluation for the use of online quiz competitions amongst medical students. Optional online quizzes with small incentives may foster motivational competition among medical students, increase online interactions with faculty, and serve as study material for exams.

Lymphangitis occurring after intralesional Candida antigen injection for verruca vulgaris

Verruca vulgaris is a common dermatological disease with many treatment options including destructive modalities and more recently, immunotherapy. Intralesional injections of Candida antigen have been described as a safe and effective treatment with the most common adverse reactions including local reactions (burning, blistering, peeling), local erythema, and pain at the injection site. We describe the first reported case of lymphangitis after intralesional Candida antigen injection for verruca vulgaris in a healthy 18-year-old woman. The lymphangitis rapidly resolved with ibuprofen and cold compresses. Physicians should be aware of this potential adverse reaction when using this treatment modality and should be familiar with appropriate treatment of subsequent lymphangitis.

Non-invasive methods to establish the diagnosis of terra firma-forme dermatosis: The SMART (Skin Modified by Alcohol Rubbing Test) evaluation and dermoscopy

Terra firma-forme dermatosis may mimic a variety of hyper pigmented dermatoses.  The diagnosis can be characterized using dermoscopy and confirmed with the SMART (Skin Modified by Alcohol Rubbing Test) evaluation.  When terra firma-forme dermatosis (Duncan’s dirty dermatosis) is clinically suspected, clearance of the dermatosis follows rubbing the affected skin with 70% isopropyl alcohol.

Effective local anesthesia for onabotulinumtoxin A injections to treat hyperhidrosis associated with traumatic amputation

Background: Botulinum toxin type A (BTX-A) injections are an effective treatment for controlling hyperhidrosis at sites of amputation. Hyperesthesia associated with amputated limbs is a major barrier to performing this procedure under local anesthesia.

Objective: To present a novel method for improving local anesthesia with BTX-A injections.

Methods & Results: A 29-year-old military veteran with a below-the-knee amputation of his right leg was suffering from amputation site hyperhidrosis, which was impeding his ability to comfortably wear a prosthesis. Prior to presenting to our clinic, the patient received one treatment of BTX-A injections to his amputation stump while under general anesthesia for surgical repair of trauma-related injuries. In our dermatology clinic, we repeated the procedure using topical lidocaine-prilocaine (30 gm total) for local anesthesia. This provided effective relief of hyperhidrosis for 6 months, but the procedure was very painful (9/10 intensity). We repeated the same procedure 6 months later, using ice in addition to topical lidocaine-prilocaine (30 gm) for local anesthesia; this resulted in reduced pain (3/10 intensity) for the patient.

Conclusions: We suggest using ice in combination with a topical anesthetic as an effective method for pain control that avoids general anesthesia in treating amputation-associated hyperhidrosis.


Lesões vesiculares e prurido intenso em paciente com sífilis secundária:manifestação clínica atípica

Syphilis is an infectious disease with mucocutaneous lesions that are characteristic of their stage (primary, secondary, or tertiary). These are not always typical and may have other morphologies and unusual symptoms, making diagnosis difficult. The report herein is of a healthy woman with vesicular lesions associated with intense itching.  The diagnosis of secondary syphilis was confirmed with VDRL 1/512 and FTA Abs positive.  Histopathology showed spongiosis in the epidermis and infiltrated lymphocytes and plasma cell in the dermis.  Clinical improvement occurred after the first dose of benzathine penicillin. In the literature, few cases of vesicular lesions in syphilis have been found and itching is mentioned as uncharacteristic . Histology showing spongiosis is also unusual.

There’s no place like home: an analysis of migration patterns of dermatology residents prior to, during, and after their training

Previous studies have established migration patterns between the geographic location of physicians’ residency programs and their first post-training job. Our study explores the patterns of migration of pre-residency education locations with residency and post-residency geography. We analyzed responses to an annual survey administered between 2008 and 2013 to participants of the board examination review courses organized by Galderma Laboratories. Geography of high school (HS), medical school (MS), residency, and first job location were highly correlated. The Midwest and South retained the most residents from HS (70% each), whereas the West retained the lowest percent of residents from HS (33%). The West and Northeast exported about half of their HS graduates to the South and MW for residency. The South retained the largest proportion of its trainees post-residency (75%). Our data revealed that both HS and MS locations are closely related to residents’ ultimate employment locations. This information may be useful to training program directors and chairpersons as they manage recruitment and retention of trainees and faculty and may inform plans to address geographic workforce imbalances.