Wood's Lamp Research Articles

The epidemiology of canine and feline dermatophytoses in southern Italy

A total of 424 animals (268 dogs and 156 cats) with skin lesions (alopecia and peripheral scaling) were examined from January 1999 to December 2002. Of the 424 samples examined, 99 (23.3%) yielded a positive culture and, in particular, 20.5% of the dog samples and 28.2% of the cat samples. Microsporum canis was the most common dermatophyte isolated from dogs and cats (77.7%), followed by geophilic dermatophyte species (M. gypseum, Trichophyton terrestre). Young dogs and cats, especially those younger than 1 year, showed a statistically significant higher prevalence of M. canis infection than older animals. No statistically significant association was found between infection and sex in cats, while male dogs were more affected by dermatophytes. Among breeds, Yorkshire terriers showed the highest positivity (50%) caused mainly by M. canis (46.6%), while no differences were noticed for cats. A significantly higher prevalence of positive samples was registered in summer and in autumn for cats. The presence of dermatophytes was not associated with itching. The diagnostic value of Wood's lamp fluorescence and microscopic examination proved to be scarce compared with fungal cultures as only 45.5% of the 77 samples that tested positive for M. canis at the cultural examination was positive under Wood's lamp florescence and 53.2% at microscopic examination.

Efficacy of pre‐treatment with lufenuron for the prevention ofMicrosporum canisinfection in a feline direct topical challenge model

Oral lufenuron is reportedly an effective treatment for some cats with dermatophytosis. The purpose of this study was to determine if lufenuron, when used as a pre-treatment prior to challenge exposure, would be protective against the development of infection after the direct topical application of fungal macrocondia (Microsporum canis spores). Three groups (n = 6/group) of juvenile cats were treated with either monthly oral lufenuron (30 or 133 mg/kg) or placebo. After 2 months of treatment, kittens were challenged using 10(5)Microsporum canis spores applied to the skin under occlusion. Cats were examined weekly and the following data collected: Wood's lamp examination; scoring for scale/crust, erythema and induration; lesion size; and the development of satellite lesions. Fungal cultures were performed bi-weekly. All cats became infected; the infections progressed, and then regressed, in a similar fashion in all groups. There were no consistent statistically significant differences in weekly infection scores between treated and untreated cats throughout the study. Treated cats did not recover faster than untreated cats. We conclude that oral lufenuron at the dosing schedule and conditions used in this study did not prevent dermatophytosis or alter the course of infection by direct topical challenge.

Wood's Lamp Employed as a Provocative Technique to Identify Pseudoseizures

We present a case of a 12-year-old female who presented to the emergency department with ictal phenomena suggestive of pseudoseizures. A Wood's lamp was successfully employed to induce the stereotypic phenomena and thereby identify the ictal events as nonepileptiform. Use of the Wood's lamp has not previously been reported as a provocative stimulus to induce pseudoseizures. Given its noninvasive nature and ready availability, the Wood's lamp should be considered for identification of pseudoseizures.

P‐87 Alopecia in two guinea pigs due to hypopodes of Acarus farris

Mites are frequent agents of skin diseases in veterinary dermatology, particularly in rodents. The authors report an original case of infestation in two guinea pigs of the same household. Two adult guinea pigs were presented with a 3‐month history of alopecia, matted hair, erythema, scales and mild pruritus. The first guinea pig showed almost complete truncal alopecia with mild scaling, whereas the other one had only recently developed mild alopecia of the abdomen and mild pruritus. Numerous live, long‐legged mites were present both in adhesive tape and skin scrapings. Mycology (Wood's lamp and DTM agar culture) was negative. Histopathological examination of a skin biopsy did not reveal any significant inflammatory disease and morphological changes were limited to hair follicles in the telogen phase. Mites were identified as hypopodes of Acarus farris (Acaridae), but no adult stages were present. Hypopodes were also found in the hay. Control was obtained with acaricidal treatment with Phoxim 0.05% once weekly for 4 weeks, and the elimination of contaminated hay. The lesions and the alopecia resolved rapidly. Hypopodes are additional nymphal stages of some mites of the suborder Astigmata. They develop for dispersing or dormancy under disadvantageous conditions. They can be active or inert, and some can be phoretic on the skin surface or intrafollicular. Although nonparasitic, they may cause dermatitis. Acarus farris have been rarely mentioned in the literature as a cause of dermatitis. This condition could be underdiagnosed or misdiagnosed in veterinary dermatology. Funding: Self‐funded.

P‐36 Juvenile idiopathic nasal scaling in three Bengal cats

Affected cats were three Bengals, one male and two females, whose age at onset of lesions ranged from 13‐ to 20‐weeks old. Nasal planum scaling progressed to thick crusting, consequent exfoliation and exposure of underlying erosions. No signs of pruritus or pain were present but mild respiratory signs were noticed. In all cats, haematology and biochemistry were normal, they were FIV and FeLV negative, PCR for herpesvirus, calicivirus and Chlamydia were negative, and viral isolation for calicivirus and herpesvirus was negative. Wood's lamp examination was negative, as were bacterial and fungal cultures. Cytology showed exfoliating keratinocytes. A skin biopsy taken from one case showed no significant changes. Biopsies from the nasal planum of four dead cats with nondermatological conditions (controls) were collected for comparative studies. Morphometry to record the percentage of the granular layer (GL) and stratum corneum (SC) on the total thickness of the epidermis of the nasal planum was performed. The GL and SC accounted for 10.2 and 21.7% of the epidermal thickness in the affected cat, compared to 18.3 and 20.2%, respectively, in the controls. A significant reduction (P < 0.02) of the SC thickness was detected in the affected cat compared to controls. No treatment was instituted as all cats underwent complete (two cats) or nearly complete (one cat) resolution. The reported cases share the same breed, age at onset, type of lesions and a similar outcome. A reduction of the SC thickness in one of the affected cats was recorded. Therefore, an underlying congenital condition is suspected that manifests with high epidermal cell turnover and normal keratinization. Funding: Self‐funded.

P‐13 Dermatophytosis in domestic cats: treatment with lufenuron

Preliminary studies showed that lufenuron inhibits chitin synthesis, a dermatophyte cell wall constituent, and may be effective in the treatment of dermatophytosis. Our purpose was to evaluate the efficacy of lufenuron in the treatment of feline dermatophytosis. Forty‐six cats (Persians and mixed‐breed cats from 1‐month to 4‐years old) naturally infected with Microsporumcanis were included in this study. Fifteen cats were treated isolated in cages in the veterinary hospital and 31 were treated in their home environment (some with access to the outdoors). Dermatophyte skin lesions were seen in 29 animals while 17 other cats were asymptomatic carriers. Wood's lamp, direct microscopic examination of hairs, fungal culture and skin biopsies were used for the diagnosis. Affected cats and all in‐contact animals received lufenuron at a dose of 120 mg/kg every 21 days for four treatments. Of the 29 symptomatic cats treated with lufenuron, 70% recovered within 21 days and 28% within 42 days of initiation of therapy. One cat had only partial recovery and another was euthanized. Negative fungal culture was recorded only after the fourth dose of lufenuron in 98% of affected cats and 100% of asymptomatic carriers. There was no difference in clinical response to lufenuron between the cats treated in their home environment and those treated in the veterinary hospital. Side effects were not observed, thus the drug proved to be safe and effective for the treatment of dermatophytosis. Funding: Novartis.

The Role of Clinical Factors, Wood's Lamp Examination, and Slit Lamp Examination in the Diagnosis of Eye Disease in the ED

The Role of Clinical Factors, Wood's Lamp Examination, and Slit Lamp Examination in the Diagnosis of Eye Disease in the ED

Prevalence of pityriasis versicolor in young Italian sailors.

Pityriasis versicolor is a superficial fungal disease with a world-wide distribution, but there are few available studies on its prevalence in the general population. To assess the prevalence of pityriasis versicolor in a representative sample of young Italian sailors, evaluating the influence of habits and risk factors in the affected individuals. Young cadets (n = 1024: 975 men and 49 women, mean age 22 years) of the Italian Navy Petty Officers' School in Taranto were consecutively examined by the same observer. The diagnosis of pityriasis versicolor was based on clinical picture and/or Wood's lamp examination. All the subjects filled in a questionnaire about sport practice, swimming pool attendance, marching, presence of hyperhidrosis and a positive clinical history of pityriasis versicolor in the past. The affected individuals were also asked if they were aware of their skin lesions. Differences between answers of affected and unaffected subjects were tested by Fisher's exact P-value test, and odds ratios were calculated. Pityriasis versicolor was diagnosed in 22 subjects (2.1%), all men, of whom 15 (68%) were not aware of their condition. No statistical association was found between active pityriasis versicolor and sport practice, swimming pool attendance, marching or presence of hyperhidrosis. A significant association [odds ratio 8.7 (95% confidence interval 3.3-21.5); Fisher's exact P-value test P < 0.01] was documented between active pityriasis versicolor and a previous clinical history of pityriasis versicolor. The prevalence of pityriasis versicolor in this sample of young Italian sailors was not high, in agreement with the available surveys performed in the general population in temperate climates. Many affected subjects were not aware of their condition. The only important factor associated with pityriasis versicolor was a previous history of pityriasis versicolor. This observation could confirm the hypothesis that constitutional factors, e.g. seborrhoea and chemical constitution of sebum, may play a crucial role in temperate climates, leading to relapsing forms of this superficial mycosis.

An Alternate Light Source to Detect Semen

AbstractThe Wood's lamp (WL) has been used in sexual assault evaluations. Recent data have shown that semen does not fluoresce with a WL and that physicians are unable to differentiate semen from other common medicaments using a WL. Objectives: To determine whether physicians could differentiate semen from other products using an alternate light source (ALS), and to investigate whether a brief training period with the ALS would enhance physicians' ability to differentiate between semen and other commonly used products. Methods: An ALS, Bluemaxx BM500, was found to cause semen to fluoresce. Physicians were first asked to use this ALS to identify semen and then to distinguish between a semen sample and other products. Physicians then received a training class on the use of the ALS and were then asked to differentiate semen from other products. Results: All physicians identified the semen as fluorescing and 25% successfully differentiated the semen from the other products using the ALS. Products most commonly mistaken for semen were a hand cream, Castille soap, and bacitracin. After the training session, 83% of the physicians successfully differentiated the semen from other products. The ALS, while not specific for semen identification, was 100% sensitive for it. Conclusions: Physicians instructed in the use of an alternate light source (BM 500) are able to identify semen as fluorescing and can differentiate semen (after a training session) from other commonly used products.

An Alternate Light Source to Detect Semen

The Wood's lamp (WL) has been used in sexual assault evaluations. Recent data have shown that semen does not fluoresce with a WL and that physicians are unable to differentiate semen from other common medicaments using a WL. To determine whether physicians could differentiate semen from other products using an alternate light source (ALS), and to investigate whether a brief training period with the ALS would enhance physicians' ability to differentiate between semen and other commonly used products. An ALS, Bluemaxx BM500, was found to cause semen to fluoresce. Physicians were first asked to use this ALS to identify semen and then to distinguish between a semen sample and other products. Physicians then received a training class on the use of the ALS and were then asked to differentiate semen from other products. All physicians identified the semen as fluorescing and 25% successfully differentiated the semen from the other products using the ALS. Products most commonly mistaken for semen were a hand cream, Castille soap, and bacitracin. After the training session, 83% of the physicians successfully differentiated the semen from other products. The ALS, while not specific for semen identification, was 100% sensitive for it. Physicians instructed in the use of an alternate light source (BM 500) are able to identify semen as fluorescing and can differentiate semen (after a training session) from other commonly used products.

Detection of Female Lower Genital Tract Dysplasia Using Orally Administered 5-Aminolevulinic Acid Induced Protoporphyrin IX: A Preliminary Study

Previous studies have suggested that 5-aminolevulinic acid (ALA) may be used topically on the cervix to allow optical detection of cervical dysplasia, based on the fluorescence of protoporphyrin IX (PpIX) synthesized in situ from ALA. However, the uniformity of distribution of topically applied PpIX and the sensitivity and specificity of detection are not optimal. The current study was undertaken to demonstrate the feasibility of administering ALA by mouth (po) with the hypothesis that systemic administration might provide a more reliable diagnostic tool. Oral ALA was administered to 14 patients with abnormal Pap smears in a dose- and time-intensity design. Institutional review board approval was obtained. A starting dose of 10 mg/kg of po ALA was administered and colposcopy was performed in 3 patients at 1 h, 3 patients at 2 h, 6 patients at 3 h, and 2 patients at 4 h. The study was written with the intent to increase the dose in 10 mg/kg increments if fluorescence was not detected; however, fluorescence was detected at the first dose level. Liver function tests were checked pre and post ALA and follow-up telephone calls were made regarding possible side effects. Both white and blue light colposcopy examinations were performed by two blinded clinicians and biopsies of all abnormal areas were performed. All patients tolerated po ALA well, with no systemic side effects. At the 10 mg/kg dose there was no reported nausea or photosensitivity. Optimal fluorescence was achieved at the 3-h time point, with quenching noted at the 4-h time point. Excellent absorption was documented with fluorescence of the lip demonstrated with Wood's lamp. In some cases fluorescence correlated with dysplasia on biopsy. 5-ALA given via the po route and at the dose and time period studied is well tolerated and affords fluorescence of the cervix. Future study is needed to demonstrate the successful identification of dysplastic lesions, with the ultimate goal of treating dysplasia of the lower genital tract with 5-ALA and light therapy.

Fluconazole versus ketoconazole in the treatment of tinea versicolor

BACKGROUND : A number of effective topical therapies are available for the treatment of tinea versicolor (TV). However, topical antifungals are difficult to apply to a large body surface area and for this reason TV is perhaps more easily treated with systemic agents. METHODS : A total of 128 patients with TV, aged 15-55 years, were entered into a randomized, double-blind, clinical trial comparing the efficacy and tolerance of two regimens of oral treatment for TV. The patients were randomly divided in two groups: group 1 received two 150 mg capsules of fluconazole in a single dose repeated weekly for 2 weeks; and group 2 received two 200 mg tablets of ketoconazole in a single dose repeated weekly for 2 weeks. Diagnosis of TV was made clinically by direct KOH preparation and Wood's lamp examination. RESULTS : Of 128 patients, 100 completed the study and no major side-effects were noted between the two treatment regimens. Results of the study showed no significant differences in efficacy, safety and tolerability between the two treatment regimens. The maximal cure rate was achieved at 8 weeks from the start of treatment and decreased slightly afterwards. CONCLUSIONS : Fluconazole and ketoconazole demonstrated similar efficacy in the treatment of TV. We also demonstrated a lack of correlation between mycological cure and hypopigmentation at the end of treatment (2 weeks) and the usefulness of Wood's lamp examination in detecting cure of TV.

Comparison of a single 400 mg dose versus a 7-day 200 mg daily dose of itraconazole in the treatment of tinea versicolor

BACKGROUND : Tinea (pityriasis) versicolor is a superficial infection of the stratum corneum by the lipophilic fungus known as Malassezia furfur . OBJECTIVE : To evaluate the efficacy and safety of a 400 mg single dose or 7-day 200 mg daily dose of itraconazole capsules in the treatment of mycologically confirmed pityriasis versicolor. METHODS : A total of 50 patients were entered into a randomized, open, clinical trial comparing a 400 mg single dose ( n = 24 for group 1) with a 7-day 200 mg daily dose ( n = 26 for group 2) of itraconazole. Clinical signs and symptoms and mycologic evaluation (potassium hydroxide preparation and Wood's lamp) were performed before treatment, and at weeks 3 and 6 after treatment. RESULTS : Both regimens of itraconazole were effective. Our results showed that there were no significant differences in efficacy and safety between the two treatment regimens (chi-square tests, p > 0.05). CONCLUSIONS : On the basis of these findings, a single dose of itraconazole 400 mg/day was as effective as the 7-day 200 mg daily dose in the treatment of pityriasis versicolor.

Diagnostic techniques for dermatophytosis

This article reviews the use of common diagnostic tools for the identification and isolation of dermatophyte infections in small animals. The use of the Wood's lamp as a screening tool is discussed, along with its usefulness as an aid in the microscopic examination of hairs for fungal elements. Tests for the definitive diagnosis of dermatophytosis are highlighted and include: direct examination of hair for ectothrix spores, fungal cultures, and skin biopsy. Sampling techniques, procedures, and interpretation of test results are also detailed.

Comparison of Intradermal and Subcutaneous Injections in Lymphatic Mapping

Background. Sentinel node biopsy (SNB) for melanoma, with its intradermal (ID) injection, has a higher success rate than SNB for breast cancer, which is typically performed with a subcutaneous (SC) or peritumor injection. It is hypothesized that this is in part due to a slower transit time of lymphatic mapping agents through the parenchymal lymphatics of the breast. No study has investigated differences in transit time between different tissues to account for this clinical observation. The goal of the study was to compare transit time between ID and SC injections with common agents used in lymphatic mapping.Methods. Four injection sites on five domestic pigs were used. Sites were bilateral and included cervical, forelimb, hindlimb, and flank areas. Agents included technetium sulfur colloid (Tc99, filtered and unfiltered), isosulfan blue (IB) dye, and fluorescein (FL) dye. At each site both ID and SC injections were made and the transit time to reach the sentinel node was recorded. The transit time differences were calculated per centimeter distance from the draining lymph node basin.Results. Sentinel nodes were identified draining all sites and found to be hot, blue, or fluorescent (using a Wood's lamp for identification). The cervical and forelimb injection sites drained to the same cervical lymph node basin and both SC and ID injection sites drained to the same sentinel node. Similarly, the hindlimb and flank injection sites both drained to inguinal lymph node basins. The slowest transit time occurred with Tc99 injected SC and the fastest occurred with Tc99 injected ID, whereas both FL dye and IB traveled rapidly to the sentinel node whether injected SC or ID. Large differences were found using unfiltered Tc99 depending on its injection ID (2.7 s/cm ± 0.5) vs SC (249 s/cm ± 14.7, P = 0.008).Conclusions. Tc99 ID injections were significantly faster than SC injection. The slowest and fastest SC injection agents were unfiltered Tc99 and IB, respectively. Dermal injections provide faster transit of lymphatic agents and may improve the identification rate when applied to patients with breast cancer.

Melasma treated with hydroquinone, tretinoin, and a fluorinated steroid.

A retrospective study was conducted in six Hispanic women, 35–55 years of age, with Fitzpatrick skin types IV to VI, presenting to an academic dermatology clinic for resistant melasma (Table 1). They had all been treated with topical hydroquinone (2–4%) without success prior to being seen in our clinic. Patient demographics Patient Age Country of origin Affected area Duration of disease (years) Severity Type of melasma 1 39 El Salvador Cheeks, upper lip 10 Moderate Epidermal 2 37 Mexico Cheeks 12 Moderate Epidermal 3 35 Mexico Cheeks 7 Moderate Combination 4 35 Mexico Cheeks 9 Moderate Epidermal 5 55 Mexico Cheeks, jaw 20 Moderate Combination 6 32 Mexico Cheeks, forehead 6 Moderate Epidermal A Wood's lamp was used to determine whether the melasma was epidermal, dermal, or a combination of the two. The patients were treated with a mixture containing 0.05% tretinoin cream, 0.05% triamcinolone acetonide cream, 6% hydroquinone, and 0.1% ascorbic acid (as a preservative) applied at night, and a sun protection factor (SPF) 15 UVB‐blocking sunscreen was applied each morning. They were instructed to use the mixture on the affected areas nightly for a period of 8 weeks. All of the patients were evaluated at baseline and monthly during the treatment period. Improvement in pigmentation was assessed at each subsequent visit by clinical examination and photography with polarized filters as well as black and white UV reflectance photography (Canfield Scientific, Inc.). Improvement was determined subjectively on a three‐point scale as follows: I, mild improvement; II, moderate improvement; III, significant improvement.

Does fluorescent urine indicate antifreeze ingestion by children?

Fluorescent urine has been reported to indicate antifreeze ingestion. Recently, we evaluated a child who was suspected of ethylene glycol ingestion. Although she had fluorescent urine, subsequent studies showed that she had not ingested antifreeze. We tested whether fluorescent urine indicates antifreeze ingestion by children. A convenience sample of urine specimens from 30 hospitalized children was obtained. All of the patients had been hospitalized for reasons unrelated to poisoning. The specimens were viewed with a Wood's lamp, and the samples were identified as fluorescent or not fluorescent. A second convenience sample of urine specimens from a group of 16 healthy children was obtained, and these specimens were identified as fluorescent or not fluorescent in a similar manner. The majority of urine specimens obtained from children are fluorescent. There is variation in the interpretation of urine fluorescence among observers. The type of container used may influence the finding of fluorescence. Fluorescent urine is not an indicator of ethylene glycol antifreeze ingestion by children.

Penile incarceration with metal objects--a review of procedure choice based on penile trauma grade.

To outline treatment guidelines according to level of penile trauma for penile incarceration by metal devices. A post-1950 (hand-held powered cutting tool era) Medline search was performed. Cases were divided into four groups: string techniques and variants with and without aspiration of blood from the glans; aspiration techniques; cutting devices; and surgical techniques. Trauma grade (according to Bhat et al., 1991), site time (incarceration time), removal technique, removal time, anesthesia and recovery time were assessed. The string technique and variants were used for grades 1-3. They had short removal (30-120 min), site (3-72 h) and recovery (1-24 h) times. Occasional glans decompressive with blood aspiration was required. Anesthesias included none (wrapping without glans aspiration), i.m. morphine and general (glans aspiration). Pure aspiration techniques used multiple needle punctures for grades 2-3. Aspiration cases had short site times (8-14 h), but required a spinal or general anesthesia. Cutting device cases (grades 1-5) required general anesthesia, had a short removal times (45-90 min), but long site (7 h-30 days) and recovery (2-66 days) times. Surgical degloving was utilized mainly for grade 5 cases, required spinal or general anesthesia, had short site (2-30 days), but long recovery (9-28 days). The string, wrapping, aspiration techniques and cutting devices are suited for grades 1-3. Cutting requires a shield to avoid blade trauma and water-cooling to prevent thermal injury. Suspected underlying devitalized tissue (e.g. grade 4) is examined by Wood's lamp. Failure to identify gangrenous tissue will result in post interventional complications and a prolonged recovery time.

Microsurgical anatomy of sellar region in cadavers using a photographic technique with fluorescein

The microsurgical anatomy of sellar regions in 20 cadavers with a 12 hours maximum post mortem was studied. Fluorescein was used as contrast for vascular anatomy examination. The use of fresh specimen and fluorescein had the objective of avoiding any distortion of normal anatomy. The drug was diluted with water or, in order to have more consistency, in gel for ultrasonography. Contrast injection was made into the internal carotid artery and photographs were taken with three different kinds of lighting: 1) only with Wood's lamp; 2) Wood's lamp and normal white light; 3) only with white light. Lighting only with Wood's lamp showed more contrast. After measurement, data often showed discrepancies with other authors' data. The photographic technique with fluorescein is simple and accessible; the drug showed high quality as a vascular contrast for neuroanatomic research.

Corneal abrasions associated with pepper spray exposure

Pepper spray containing oleoresin capsicum is used by law enforcement and the public as a form of nonlethal deterrent. Stimulated by the identification of a case of a corneal abrasion associated with pepper spray exposure, a descriptive retrospective review of a physician-maintained log of patients presenting to a jail ward emergency area over a 3-year period was performed. The objective was to give some quantification to the frequency with which an emergency physician could expect to see corneal abrasions associated with pepper spray exposure. Of 100 cases of pepper spray exposure identified, seven patients had sustained corneal abrasions. We conclude that corneal abrasions are not rare events when patients are exposed to pepper spray and that fluorescein staining and slit lamp or Wood's lamp examination should be performed on all exposed patients in whom corneal abrasions cannot be excluded on clinical grounds.