Cause Of Photosensitivity Research Articles

Incidence of Photosensitization in Husbandry Animals: A Meta-Study on the Effects of Feed Diversity and Feed Choice

As this is a meta-study, we examined whether plant species diversity in the feed and the possibility of feed choice would influence the number of cases of photosensitization in farm animals. We evaluated 110 scientific references which described 172 cases of photosensitization worldwide, mainly in husbandry animals between 1926 and 2022. More than 50% of the cases occurred in South America and Australia. Among the animal species, sheep and cattle were statistically overrepresented. A total of 35 organisms were revealed to be phototoxic: 24 herbs, 2 grasses, 7 woody species, and 2 kinds of fungi. Animals developed mainly secondary photosensitization due to fresh feed (71.8%) of normal quality (88.1%), indicating that the phototoxic agents are from liver-toxic plants such as the grass Brachiaria and the herb Froelichia. Horses fell ill chiefly with primary photosensitization due to directly acting phototoxic agents of plant species such as the herbs Medicago and Pastinaca, both in fresh and conserved feed. Goats manage to avoid phototoxic plants under both high and low feed diversity if they still have free choice between plant species. High feed diversity reduced the incidence 2.4-fold, while enabled selection possibility even reduced it 7.5-fold. Since the lack of choice between forage plants was revealed to be the main cause of photosensitization, this knowledge could be used to prevent the disease in livestock.

Polymorphous light eruption in children – clinical presentation, differential diagnosis and treatment

Polymorphous light eruption is classified as an immune-mediated photodermatosis. It is the most common cause of photosensitivity in children between 6 and 14 years old. It is characterised by pruritic or tingling erythematous papular or plaque lesions of sunlight-exposed skin which occur in spring or early summer. The first signs of polymorphous light eruption typically appear several hours to days after the first exposure to intense sunlight and take the form of an irritable rash persisting for a few days, and subsiding within a week or two with minimal or no scarring. Its recurrences may have a detrimental impact on the quality of life. Due to the significant heterogeneity of clinical manifestations of polymorphous light eruption, the disorder is relatively challenging to diagnose. The differential diagnoses include photosensitivity associated with lupus erythematosus, solar urticaria, actinic prurigo, erythema multiforme, photocontact allergic dermatitis, and genetic dermatoses. UVA and UVB phototesting followed by histological examination is an important diagnostic tool to objectify light-related symptoms. Once the diagnosis is established, the patient should be monitored and educated on prevention. The management of polymorphous light eruption is based on prevention such as sun protection and sunscreens. The first-line treatment includes glucocorticoids and antihistamines.

POLYMORPHOUS LIGHT ERUPTION AND ITS ASSOCIATION WITH HYPOTHYROIDISM AND AUTOIMMUNE THYROIDITIS – A COMPARATIVE CROSS-SECTIONAL STUDY

BACKGROUND In many parts of the world, polymorphous light eruption (PLE) is the commonest cause of photosensitivity. Previous studies have suggested the association of PLE with multiple autoimmune diseases. Few studies are available suggesting the association of PLE with autoimmune thyroiditis. We have undertaken this study to conrm such an association and to predict which cases of PLE are likely to have hypothyroidism and autoimmune thyroiditis. METHODS This was a cross-sectional study with comparative group with 75 PLE cases and 75 controls. Thyroid function test (TFT) was done for all subjects and, if found abnormal, anti-thyroid peroxidase (TPO) antibodies were tested. The studied parameters were compared using Pearson's chi-squared test for signicance. RESULTS The male to female ratio was 1:2.1. Hypothyroidism and autoimmune thyroiditis were signicantly present in PLE cases. PLE lesions with papular morphology, persistent and recurrent PLE, positive family history and associated other autoimmune diseases were signicantly associated with autoimmune thyroiditis. CONCLUSION PLE is signicantly associated with hypothyroidism and autoimmune thyroiditis. Hence we suggest screening of PLE patients for hypothyroidism and, if required, for autoimmune thyroiditis for early diagnosis and treatment.

Systemic drug photosensitivity-Culprits, impact and investigation in 122 patients.

Systemic drugs are a potentially reversible cause of photosensitivity. We explore prevalence, impact, phototest findings and culprit drugs. Retrospective review of patients was diagnosed with drug-induced photosensitivity in a specialist photoinvestigation centre (2000-2016), using data recorded in standardized pro forma. Patients underwent detailed clinical evaluation. Monochromator phototesting was performed to 300±5 nm, 320±10 nm, 330±10 nm, 350±20 nm, 370±20 nm, 400±20 nm, 500±20nm and 600±20 nm. Broadband UVA and solar-simulated radiation (SSR) testing were performed, and photopatch testing and laboratory tests examined for other causes of photosensitivity. DLQI was evaluated. Prevalence of drug-induced photosensitivity was 5.4% (122/2243) patients presenting with photosensitivity. Patients with drug-induced photosensitivity were 52.5% female; median 62years (range 11-86); phototype I (17.2%), II (39.3%), III (26.2%), IV (6.5%), V (4.1%). Fifty-five (45.1%) patients had reduced erythemal thresholds on monochromator phototesting: 83.6%% to UVA alone, 14.5% to both UVA and UVB, 1.8% to UVA and visible light; 61.4% (n=75) showed abnormal response to broadband UVR. Drugs implicated: quinine (11.5%), diuretics (10.7%; thiazide 9.8%), antifungals (9.8%), proton-pump-inhibitors (9.8%), angiotensin-converting enzyme inhibitors (7.4%), anti-inflammatory drugs (6.6%), statins (5.7%), selective serotonin reuptake inhibitors (4.9%), calcium channel antagonists (3.3%), anti-epileptics (3.3%), tricyclic antidepressants (3.3%), beta-blockers (2.5%), antibiotics (2.5%), others (≤1.6% cases each). Emerging culprits included azathioprine (2.5%) and biologics (TNF-α inhibitors, denosumab; 2.5%). Median DLQI was 11 (range 2-27) for the past year. Classically described photosensitizing drugs such as thiazides and quinine remain common offenders, while emerging culprits include biologics such as TNF-a inhibitors and proton-pump-inhibitors. There is very large impact on life quality; identification facilitates measures including drug cessation and implementation of appropriate photoprotection.

Drug-Induced Photosensitivity-An Update: Culprit Drugs, Prevention and Management.

Photosensitive drug eruptions are cutaneous adverse events due to exposure to a medication and either ultraviolet or visible radiation. In this review, the diagnosis, prevention and management of drug-induced photosensitivity is discussed. Diagnosis is based largely on the history of drug intake and the appearance of the eruption primarily affecting sun-exposed areas of the skin. This diagnosis can also be aided by tools such as phototesting, photopatch testing and rechallenge testing. The mainstay of management is prevention, including informing patients of the possibility of increased photosensitivity as well as the use of appropriate sun protective measures. Once a photosensitivity reaction has occurred, it may be necessary to discontinue the culprit medication and treat the reaction with corticosteroids. For certain medications, long-term surveillance may be indicated because of a higher risk of developing melanoma or squamous cell carcinoma at sites of earlier photosensitivity reactions. A large number of medications have been implicated as causes of photosensitivity, many with convincing clinical and scientific supporting evidence. We review the medical literature regarding the evidence for the culpability of each drug, including the results of phototesting, photopatch testing and rechallenge testing. Amiodarone, chlorpromazine, doxycycline, hydrochlorothiazide, nalidixic acid, naproxen, piroxicam, tetracycline, thioridazine, vemurafenib and voriconazole are among the most consistently implicated and warrant the most precaution by both the physician and patient.

Update on pediatric photosensitivity disorders

Although rare in the pediatric population, photosensitive dermatoses may begin prior to adulthood. The causes of photosensitivity are diverse, ranging from primary, immunologically mediated disorders of photosensitivity to inherited genetic or metabolic disorders. This review will highlight the key features of these disorders to familiarize the pediatric practitioner with their symptoms and any associated extracutaneous clinical or laboratory findings that may accompany them. New developments in the field of pediatric photosensitivity have been scant over recent years. While mechanisms of photosensitivity and genetic underpinnings associated with various conditions such as xeroderma pigmentosum continue to be uncovered, the literature on disorders of photosensitivity has been otherwise without many recent significant advances. Although the differential diagnosis of pediatric photosensitivity disorders is broad, it is often possible to establish the diagnosis by following an algorithmic approach. Once the correct diagnosis is rendered, this will guide any further workup that needs to be performed as well as specific management strategies.

The incidence of inherited porphyrias in Europe

Retrospective estimates of the prevalence of porphyrias have been reported but there has been no large scale prospective study of their incidence. The European Porphyria Network collected information prospectively over a 3year period about the number of newly diagnosed symptomatic patients with an inherited porphyria (335 patients from 11 countries). Prevalence was calculated from the incidence and mean disease duration. The incidence of hepato-cellular carcinoma (HCC) in acute hepatic porphyria and the prevalence of patients with recurrent acute attacks of porphyria were also investigated. The incidence of symptomatic acute intermittent porphyria (AIP) was similar in all countries (0.13 per million per year; 95% CI: 0.10 - 0.14) except Sweden (0.51; 95% CI: 0.28-0.86). The incidence ratio for symptomatic AIP: variegate porphyria: hereditary coproporphyria was 1.00:0.62: 0.15. The prevalence of AIP (5.4 per million; 95% CI: 4.5-6.3) was about half that previously reported. The prevalence of erythropoietic protoporphyria (EPP) was less uniform between countries and, in some countries, exceeded previous estimates. Fourteen new cases of HCC (11 from Sweden) were reported in patients with acute porphyria. Sixty seven patients (3 VP; 64 AIP: 53 females, 11 males) with recurrent attacks of acute porphyria were identified. The estimated percentage of patients with AIP that will develop recurrent acute attacks was 3-5%. In conclusion, the prevalence of symptomatic acute porphyria may be decreasing, possibly due to improved management, whereas the prevalence of EPP may be increasing due to improved diagnosis and its greater recognition as a cause of photosensitivity.

Pediatric photosensitivity

Photosensitivity is a rarely encountered problem in the pediatric population. It may be caused by a diverse group of primary, idiopathic photosensitivity conditions, or may reflect photoexacerbation of an existing dermatosis. In addition, there are several genodermatoses, metabolic disorders, and connective tissue disorders that can present with photosensitivity, usually in addition to other extracutaneous clinical and laboratory findings. It is important that both dermatologic and pediatric practitioners be able to recognize the various causes of photosensitivity, as well as be familiar with the associated stigmata and necessary workup, if needed, of each particular disorder. This review offers an approach to the pediatric patient who presents with photosensitivity, with emphasis on arriving at the proper diagnosis, necessary evaluations, and management strategies.

Systemic photosensitivity due to a contraceptive patch

Hormonal contraceptives are a known but rarely reported cause of photosensitivity. A 35-year-old female developed several episodes of a prurigionous papulovesicular eruption located on sun-exposed areas that resolved without scarring in days. She had been using a transdermal contraceptive (EVRA: norelgestromin and ethinyloestradiol) for 3 years, and once it was stopped, the patient became asymptomatic. She had another episode after the use of oral contraceptives (YAZ: ethinyloestradiol and drospirenone). The biopsy of the lesions showed a spongiotic dermatitis. Minimal erythema dose was diminished when the patient was using EVRA and YAZ and became normal when they were withdrawn. Phototesting with UVA, photopatch testing and blood porphyrins were normal. Antinuclear antibodies were 1/80 initially and were 1/320 6 months later. Anti-deoxyribonucleic acid antibodies, extractable nuclear antigens, anti Ro and Anti La were negative and no systemic symptoms had developed. When all hormonal contraceptives were stopped, the patient became asymptomatic. We report a case of systemic photosensitivity induced by the contraceptive patch. To the best of our knowledge, no other cases induced by transdermal contraceptives have been reported previously.

Sheep poisoning by Panicum dichotomiflorum in northeastern Brazil

Different species of Panicum, including P. dichotomiflorum,have been reported as a cause of photosensitization in sheep, horses, cattle and goats. An outbreak of hepatogenous photosensitization occurred in 3 flocks of hair sheep in the Brazilian semiarid region. Eighty one out of 365 sheep were affected and 39 died. The main affected animals were nursing lambs and sheep younger than one year old. Donkeys, goats and cattle grazing in the same pasture were not affected. Clinical signs were edema of the head, followed by dermatitis, mainly in the face, ears, and croup, ocular discharge, corneal opacity with blindness, and redness of the coronary band and hoof. At necropsy of one affected lamb the liver was yellowish. Upon histologic examination scattered necrotic hepatocytes were observed in the liver and focal areas of necrosis of myocytes appeared in the heart. Samples of P. dicotomiflorum were analyzed by TLC and those containing saponins were isolated by HPLC using RP-C18 column and eluted with a mixture of MeOH and H2O. The isolated compounds were submitted to ¹H and 13C NMR spectroscopy. Reactions were positive to furostanol saponins with the same Rf of the standard protodioscin (0.21) and methylprotodioscin (0.32). The spectroscopic results indicated a mixture of (25R)- and (25S)-protodioscin isomers in a proportion of 3:1, and methylprotodioscin.

Photosensitivity in Smith-Lemli-Opitz syndrome: A flux balance analysis of altered metabolism

Ultraviolet A photosensitivity is a debilitating symptom associated with the metabolic disorder Smith-Lemli-Opitz syndrome (SLOS). SLOS is a manifestation of the deficiency of 7-dehydrocholesterol reductase, an enzyme involved in the cholesterol biosynthesis. As a result several abnormal intermediary compounds are formed among which Cholesta 5, 7, 9(11)-trien-3beta-ol is the most likely cause of photosensitivity. The effect of various drugs acting on cholesterol biosynthetic pathway on SLOS is not clear as clinical trials are not available for this rare disorder. A Flux Balance Analysis (FBA) has been carried out using the software CellNetAnalyzer or FluxAnalyzer to gain insight into the probable effects of various drugs acting on cholesterol biosynthetic pathway on photosensitivity in SLOS. The model consisted of 44 metabolites and 40 reactions. The formation flux of Cholesta 5, 7, 9(11)-trien-3beta-ol increased in SLOS and remained unchanged on simulation of the effect of miconazole and SR31747. However zaragozic acid can potentially reduce the flux through the entire pathway. FBA predicts zaragozic acid along with cholesterol supplementation as an effective treatment for photosensitivity in SLOS.

Diagnosis and treatment of the common idiopathic photodermatoses.

The idiopathic photodermatoses are the most common cause of photosensitivity and the commonest of these are polymorphic light eruption, actinic prurigo, chronic actinic dermatitis and solar urticaria. The clinical presentation, investigation and treatment of these four disorders are presented. Spontaneous improvement does occur.

Induction of photosensitivity in sheep with Erodium moschatum (L.) L'Hérit.

Erodium moschatum is an exotic weed in the southern and southwestern coastal areas of the Western Cape Province (WCP), South Africa. It has been suspected as the cause of photosensitivity in sheep. However, attempts to induce photosensitivity by dosing it to sheep have thus far been unsuccessful. During August 1999, 2 sheep suffering from severe photosensitivity were presented for clinical examination to the Western Cape Provincial Veterinary Laboratory (WCPVL). One sheep was sacrificed for autopsy. Except for skin lesions associated with photosensitivity, no icterus or other lesions were present. Histopathological examination of affected skin revealed epidermal necrosis while the liver had no microscopic lesions. It was therefore concluded that the sheep might have been suffering from primary photosensitivity. The farm from which the sheep came, situated in the Malmesbury district, WCP, was visited to determine the source of the photodynamic agent. The flock from which the sheep originated had been grazing in a camp where E. moschatum was growing abundantly and had been heavily grazed. Some remaining Erodium in the camp was collected, pulped and dosed over a period of 7 days to an adult sheep. Another sheep was dosed simultaneously with Erodium growing on the premises of the WCPVL. Both sheep developed mild photosensitivity, which was confirmed by histopathological examination of skin biopsies. It was concluded that E. moschatum can induce photosensitivity (probably the primary type) in sheep if ingested in large quantities.

Actinic prurigo: Clinical features and HLA associations in a Canadian Inuit population

Background: Actinic prurigo (AP) is an idiopathic familial photodermatitis. AP of the Inuit is rarely reported and poorly characterized. Objective: Our purpose was to examine the clinical features and HLA associations of AP in an Inuit population. Methods: Thirty-seven Inuit subjects with AP were administered a questionnaire and underwent a cutaneous examination. Other causes of photosensitivity were excluded. HLA class I typing was performed by polymerase chain reaction and sequence-specific primers and class II typing by polymerase chain reaction and sequence-specific oligonucleotide probes. Results: Subjects were 81.1% female, 67.6% had a family history of photosensitivity, and all experienced seasonal variation. The average age at onset of photosensitivity was 29 years, and only 27% had a trend toward improvement in photosensitivity. Involvement of eyes and nonexposed skin was reported in 62.2% and 18.9% of subjects, respectively. Physical examination revealed involvement of the face (64.9%), lip (32.4%), ear (13.5%), and dorsal aspect of the hand (24.3%). HLA-DRB1*14 was present in 51.2% of subjects and 26.2% of controls (P = .022, odds ratio = 2.975). This is a previously unreported HLA association. Conclusion: AP in the Inuit is a seasonal, pruritic photodermatitis, often commencing in adulthood and worsening over time. A novel association with HLA-DRB1*14 has been discovered. Overall, this novel HLA association, the absence of HLA associations previously reported in non-Inuit populations, and clinical distinguishing features support the concept that AP in the Inuit may have a distinct immunopathogenic basis that translates into a different phenotype. It also raises the question of whether AP in the Inuit is a distinct photosensitivity disorder specific to this group that has been genetically isolated because of geographic and cultural seclusion. (J Am Acad Dermatol 2001;44:952-6.)

Hypericin content of Nova Scotia biotypes of Hypericum perforatum L.

Photosensitization of livestock in Nova Scotia has often been attributed to St. John's wort (Hypericum perforatum L.), even though the weed generally occurs at low densities. This study's objective was to determine whether levels of hypericin, the photodynamic toxin causing photosensitization, were unusually high in Nova Scotia biotypes and whether levels increased in late spring, when photosensitization most commonly occurs. The mean hypericin content in vegetative growth of 11 Nova Scotia H. perforatum biotypes was 195 μg g−1 dry wt, whereas levels in biotypes from British Columbia and Australia were at least two- and threefold higher, respectively. Levels in field-collected plants were lowest in May (60 μg g−1 dry wt) and peaked in midsummer (160–280 μg g−1 dry wt). In a controlled-environment study, hypericin levels increased linearly with increasing temperatures. Furthermore, hypericin levels were not affected by infection by Colletotrichum gloeosporioides. Thus, the hypericin content of Nova Scotia biotypes is too low to be the cause of photosensitization in livestock. Key words:Hypericum perforatum, St. John's wort, hypericin, photosensitization

Naproxen-induced pseudoporphyria: A distinctive photodermatitis

A distinctive photodermatitis developed in 22 children who had been receiving naproxen for prolonged periods. The eruption was marked by erythema, vesiculation, or increased skin fragility characterized by easy scarring of sun-exposed skin. Results of biochemical studies for porphyria were normal, and other causes of photosensitivity were believed to be unlikely. Of the 22 patients, 21 had juvenile rheumatoid arthritis; one patient had systemic lupus erythematosus. Twenty of the patients had fair skin and blue eyes. In each case, all findings except scarring resolved when naproxen was discontinued. Attention must be paid to complaints suggesting photosensitivity in children receiving naproxen.

Borrelia-like organisms in the urine of lambs suffering from eczema facialis.

IN July and September 1964 eight young lambs at this research station were attacked by a disease characterized by jaundice and sensitivity to light. The lambs were grazing two different pastures together with their dams. These pastures are poorly drained, and Narthecium ossiragum grows in one of them. This plant is a common cause of photosensitization in sheep in Norway. Three lambs in this latter pasture contracted the disease in the middle of July; the remaining five were grazing in the other pasture in September when they were attacked.

Big Game Meat Consumption in Utah and Its Relation to Consumption of Meat from Commercial Livestock

of thesis submitted in partial fulf/lllent of the requirements for the degree of Master of Science, Department of Range and Forestry, Texas A. and M. College, January, 1955. During 1954 ranches in certain areas of Texas suffered substantial losses from sporadic outbreaks of photosensitization in cattle, a malady that ha? been a constant menace in Texas for over 40 years. The present study was a continuation of work initiated in 1952 with emphasis placed on investigating grasses in Southeast Texas as the possible cause of photosensi tization. Four conditions are necessary before manifestations of photosensitization occur: (1) sunlight, (2) animals with light colored or unpigmented skin, (3) grazing of resposible plants that supply the photodynamic principle, and (4) rainfall and a period of rising temperature following an unusually dry period. In this study climatic conditions were found to be intimately related to the periodicity of the disease. Photosensitization has been observed on many soil types, ranging from deep highly leached sands, to loams and fine textured alluvials. Grazing observations combined with plant composion studies were, made to determine the diet of animals subject to the disease. Experimental feeding of southern sandbur produced mild preliminary sympt,oms. A mixture of annual grasses fed in Wharton County gave negative results. The causative plant or plants were not finally deternined, but both observations and reactions obtained from feeding strongly indicate that grasses have a definite role in the outbreaks. In general the ability of the vegetation t,o produce rejuve,nated growth after a period of drouth-induced dormancy appears to be more important than a particular species. Since pastures with photosensitized cattle were in a relatively low stage of ecological succession, a range improvement program employing correct animal numbers, proper grazing distribution, weed and brush control, and proper season of utilization could be of measurable value in eliminating photosensitization.FRANK B. STROUD. REIATION SHIP OF CRESTED WHEATGRASS STANDS TO FORAGE PRODUCTION AND SAGEBRUSH RE-ESTABLISHMENT ON BURNED SAGEBRUSH RANGE Abstract of thesis submitted in partial fulfillment of the requirements for the degree of Master of $cience in Range Mana gement, eolorado A. and M. College, 1955.of thesis submitted in partial fulfillment of the requirements for the degree of Master of $cience in Range Mana gement, eolorado A. and M. College, 1955. Re-invasion by sagebrush has been quite general on reseeded ranges and has frequently lessened or nullified efforts at range improvements. Knowledge of rates of seeding and row spacings which will produce stands of crested wheatgrass controlling sagebrush reestablishment would aid in range improvement. This study attempted to determine the effects of density and dispersion of crested wheatgrass stands upon forage production and re-establishment of sagebrush. Data were obtained on the Great Divide Experimental Range in northwestern Colorado from an area in dense sagebrush cleared by controlled burning in 1946 and seeded to crested wheatgrass at rates of 5 and 10 pounds per acre at 6-, 8-, 12and 16-inch row spacings. Rates of seeding and row spacings had no significant effect upon numbers and vigor of re-invading sagebrush, or on basal density and forage production of crested wheatgrass, as determined by observations in 1947, 1949 and 1954. Row spacings had no significant effect upon numbers of crested wheatgrass plants established; however, areas seeded at the 10-pound rate had a significantly higher number of plants in 1947 and 1949. Dispersion of crested wheatgrass plants was generally not affected by rate of seeding. An economic analysis showed that the 10-pound seeding rate increased the cost, of seeding over that of the 5-pound rate by about 50 percent. Under conditions of this study, it appears that it would require 4.5 to 7 years of use to repay the cost of seeding at the 5-pound rate and 6.5 to 10 years to repay costs at the 10-pound rate. Reseeded stands of crested wheatgrass appeared most susceptible to re-establishment of sagebrush during early life. Once sagebrush is past the seedling stage, crested wheatgrass does not offer sufficient competition to i'educe the number of sagebrush plants.FRANCIS E. NoLL. This content downloaded from 207.46.13.60 on Thu, 21 Apr 2016 07:35:28 UTC All use subject to http://about.jstor.org/terms