User login
Botanical Briefs: Primula obconica Dermatitis
Etiology
Calcareous soils of central and southwest China are home to Primula obconica1 (also known as German primrose and Libre Magenta).2Primula obconica was introduced to Europe in the 1880s, where it became a popular ornamental and decorative household plant (Figure).3 It also is a frequent resident of greenhouses.
Primula obconica is a member of the family Primulaceae, which comprises semi-evergreen perennials. The genus name Primula is derived from Latin meaning “first”; obconica refers to the conelike shape of the plant’s vivid, cerise-red flowers.
Allergens From P obconica
The allergens primin (2-methoxy-6-pentyl-1,4-benzoquinone) and miconidin (2-methoxy-6-pentyl-1, 4-dihydroxybenzene) have been isolated from P obconica stems, leaves, and flowers. Allergies to P obconica are much more commonly detected in Europe than in the United States because the plant is part of standard allergen screening in dermatology clinics in Europe.4 In a British patch test study of 234 patients with hand dermatitis, 34 displayed immediate or delayed sensitization to P obconica allergens.5 However, in another study, researchers who surveyed the incidence of P obconica allergic contact dermatitis (CD) in the United Kingdom found a notable decline in the number of primin-positive patch tests from 1995 to 2000, which likely was attributable to a decrease in the number of plant retailers who stocked P obconica and the availability of primin-free varieties from 50% of suppliers.3 Furthermore, a study in the United States of 567 consecutive patch tests that included primin as part of standard screening found only 1 positive reaction, suggesting that routine patch testing for P obconica in the United States would have a low yield unless the patient has a relevant history.4
Cutaneous Presentation
Clinical features of P obconica–induced dermatitis include fingertip dermatitis, as well as facial, hand, and forearm dermatitis.6 Patients typically present with lichenification and fissuring of the fingertips; fingertip vesicular dermatitis; or linear erythematous streaks, vesicles, and bullae on the forearms, hands, and face. Vesicles and bullae can be hemorrhagic in patients with pompholyxlike lesions.7
Some patients have been reported to present with facial angioedema; the clinical diagnosis of CD can be challenging when facial edema is more prominent than eczema.6 Furthermore, in a reported case of P obconica CD, the patient’s vesicular hand dermatitis became pustular and spread to the face.8
Allergy Testing
Patch testing is performed with synthetic primin to detect allergens of P obconica in patients who are sensitive to them, which can be useful because Primula dermatitis can have variable presentations and cases can be missed if patch testing is not performed.9 Diagnostic mimics—herpes simplex, pompholyx, seborrheic dermatitis, and scabies—should be considered before patch testing.7
Prevention and Treatment
Preventive Measures—Ideally, once CD occurs in response to P obconica, handling of and other exposure to the plant should be halted; thus, prevention becomes the mainstay of treatment. Alternatively, when exposure is a necessary occupational hazard, nitrile gloves should be worn; allergenicity can be decreased by overwatering or introducing more primin-free varieties.3,10
Cultivating the plant outdoors during the winter in milder climates can potentially decrease sensitivity because allergen production is lowest during cold months and highest during summer.11 Because P obconica is commonly grown indoors, allergenicity can persist year-round.
Pharmacotherapy—Drawing on experience treating CD caused by other plants, acute and chronic P obconica CD are primarily treated with a topical steroid or, if the face or genitals are affected, with a steroid-sparing agent, such as tacrolimus.12 A cool compress of water, saline, or Burow solution (aluminum acetate in water) can help decrease acute inflammation, especially in the setting of vesiculation.13
Mild CD also can be treated with a barrier cream and lipid-rich moisturizer. Their effectiveness likely is due to increased hydration and aiding impaired skin-barrier repair.14
Some success in treating chronic CD also has been reported with psoralen plus UVA and UVB light therapy, which function as local immunosuppressants, thus decreasing inflammation.15
Final Thoughts
Contact dermatitis caused by P obconica is common in Europe but less common in the United States and therefore often is underrecognized. Avoiding contact with the plant should be strongly recommended to allergic persons. Primula obconica allergic CD can be treated with a topical steroid.
- Nan P, Shi S, Peng S, et al. Genetic diversity in Primula obconica (Primulaceae) from Central and South‐west China as revealed by ISSR markers. Ann Bot. 2003;91:329-333. doi:10.1093/AOB/MCG018
- Primula obconica “Libre Magenta” (Ob). The Royal Horticultural Society. Accessed February 14, 2023. https://www.rhs.org.uk/plants/131697/i-primula-obconica-i-libre-magenta-(ob)/details
- Connolly M, McCune J, Dauncey E, et al. Primula obconica—is contact allergy on the decline? Contact Dermatitis. 2004;51:167-171. doi:10.1111/J.0105-1873.2004.00427.X
- Mowad C. Routine testing for Primula obconica: is it useful in the United States? Am J Contact Dermat. 1998;9:231-233.
- Agrup C, Fregert S, Rorsman H. Sensitization by routine patch testing with ether extract of Primula obconica. Br J Dermatol. 1969;81:897-898. doi:10.1111/J.1365-2133.1969.TB15970.X
- Lleonart Bellfill R, Casas Ramisa R, Nevot Falcó S. Primula dermatitis. Allergol Immunopathol (Madr). 1999;27:29-31.
- Thomson KF, Charles-Holmes R, Beck MH. Primula dermatitis mimicking herpes simplex. Contact Dermatitis. 1997;37:185-186. doi:10.1111/J.1600-0536.1997.TB00200.X
- Tabar AI, Quirce S, García BE, et al. Primula dermatitis: versatility in its clinical presentation and the advantages of patch tests with synthetic primin. Contact Dermatitis. 1994;30:47-48. doi:10.1111/J.1600-0536.1994.tb00734.X
- Apted JH. Primula obconica sensitivity and testing with primin. Australas J Dermatol. 1988;29:161-162. doi:10.1111/J.1440-0960.1988.TB00390.X
- Aplin CG, Lovell CR. Contact dermatitis due to hardy Primula species and their cultivars. Contact Dermatitis. 2001;44:23-29. doi:10.1034/J.1600-0536.2001.440105.X
- Christensen LP, Larsen E. Direct emission of the allergen primin from intact Primula obconica plants. Contact Dermatitis. 2000;42:149-153. doi:10.1034/J.1600-0536.2000.042003149.X
- Esser PR, Mueller S, Martin SF. Plant allergen-induced contact dermatitis. Planta Med. 2019;85:528-534. doi:10.1055/A-0873-1494
- Levin CY, Maibach HI. Do cool water or physiologic saline compresses enhance resolution of experimentally-induced irritant contact dermatitis? Contact Dermatitis. 2001;45:146-150. doi:10.1034/J.1600-0536.2001.045003146.X
- M, Lindberg M. The influence of a single application of different moisturizers on the skin capacitance. Acta Derm Venereol. 1991;71:79-82.
- Levin CY, Maibach HI. Irritant contact dermatitis: is there an immunologic component? Int Immunopharmacol. 2002;2:183-189. doi:10.1016/S1567-5769(01)00171-0
Etiology
Calcareous soils of central and southwest China are home to Primula obconica1 (also known as German primrose and Libre Magenta).2Primula obconica was introduced to Europe in the 1880s, where it became a popular ornamental and decorative household plant (Figure).3 It also is a frequent resident of greenhouses.
Primula obconica is a member of the family Primulaceae, which comprises semi-evergreen perennials. The genus name Primula is derived from Latin meaning “first”; obconica refers to the conelike shape of the plant’s vivid, cerise-red flowers.
Allergens From P obconica
The allergens primin (2-methoxy-6-pentyl-1,4-benzoquinone) and miconidin (2-methoxy-6-pentyl-1, 4-dihydroxybenzene) have been isolated from P obconica stems, leaves, and flowers. Allergies to P obconica are much more commonly detected in Europe than in the United States because the plant is part of standard allergen screening in dermatology clinics in Europe.4 In a British patch test study of 234 patients with hand dermatitis, 34 displayed immediate or delayed sensitization to P obconica allergens.5 However, in another study, researchers who surveyed the incidence of P obconica allergic contact dermatitis (CD) in the United Kingdom found a notable decline in the number of primin-positive patch tests from 1995 to 2000, which likely was attributable to a decrease in the number of plant retailers who stocked P obconica and the availability of primin-free varieties from 50% of suppliers.3 Furthermore, a study in the United States of 567 consecutive patch tests that included primin as part of standard screening found only 1 positive reaction, suggesting that routine patch testing for P obconica in the United States would have a low yield unless the patient has a relevant history.4
Cutaneous Presentation
Clinical features of P obconica–induced dermatitis include fingertip dermatitis, as well as facial, hand, and forearm dermatitis.6 Patients typically present with lichenification and fissuring of the fingertips; fingertip vesicular dermatitis; or linear erythematous streaks, vesicles, and bullae on the forearms, hands, and face. Vesicles and bullae can be hemorrhagic in patients with pompholyxlike lesions.7
Some patients have been reported to present with facial angioedema; the clinical diagnosis of CD can be challenging when facial edema is more prominent than eczema.6 Furthermore, in a reported case of P obconica CD, the patient’s vesicular hand dermatitis became pustular and spread to the face.8
Allergy Testing
Patch testing is performed with synthetic primin to detect allergens of P obconica in patients who are sensitive to them, which can be useful because Primula dermatitis can have variable presentations and cases can be missed if patch testing is not performed.9 Diagnostic mimics—herpes simplex, pompholyx, seborrheic dermatitis, and scabies—should be considered before patch testing.7
Prevention and Treatment
Preventive Measures—Ideally, once CD occurs in response to P obconica, handling of and other exposure to the plant should be halted; thus, prevention becomes the mainstay of treatment. Alternatively, when exposure is a necessary occupational hazard, nitrile gloves should be worn; allergenicity can be decreased by overwatering or introducing more primin-free varieties.3,10
Cultivating the plant outdoors during the winter in milder climates can potentially decrease sensitivity because allergen production is lowest during cold months and highest during summer.11 Because P obconica is commonly grown indoors, allergenicity can persist year-round.
Pharmacotherapy—Drawing on experience treating CD caused by other plants, acute and chronic P obconica CD are primarily treated with a topical steroid or, if the face or genitals are affected, with a steroid-sparing agent, such as tacrolimus.12 A cool compress of water, saline, or Burow solution (aluminum acetate in water) can help decrease acute inflammation, especially in the setting of vesiculation.13
Mild CD also can be treated with a barrier cream and lipid-rich moisturizer. Their effectiveness likely is due to increased hydration and aiding impaired skin-barrier repair.14
Some success in treating chronic CD also has been reported with psoralen plus UVA and UVB light therapy, which function as local immunosuppressants, thus decreasing inflammation.15
Final Thoughts
Contact dermatitis caused by P obconica is common in Europe but less common in the United States and therefore often is underrecognized. Avoiding contact with the plant should be strongly recommended to allergic persons. Primula obconica allergic CD can be treated with a topical steroid.
Etiology
Calcareous soils of central and southwest China are home to Primula obconica1 (also known as German primrose and Libre Magenta).2Primula obconica was introduced to Europe in the 1880s, where it became a popular ornamental and decorative household plant (Figure).3 It also is a frequent resident of greenhouses.
Primula obconica is a member of the family Primulaceae, which comprises semi-evergreen perennials. The genus name Primula is derived from Latin meaning “first”; obconica refers to the conelike shape of the plant’s vivid, cerise-red flowers.
Allergens From P obconica
The allergens primin (2-methoxy-6-pentyl-1,4-benzoquinone) and miconidin (2-methoxy-6-pentyl-1, 4-dihydroxybenzene) have been isolated from P obconica stems, leaves, and flowers. Allergies to P obconica are much more commonly detected in Europe than in the United States because the plant is part of standard allergen screening in dermatology clinics in Europe.4 In a British patch test study of 234 patients with hand dermatitis, 34 displayed immediate or delayed sensitization to P obconica allergens.5 However, in another study, researchers who surveyed the incidence of P obconica allergic contact dermatitis (CD) in the United Kingdom found a notable decline in the number of primin-positive patch tests from 1995 to 2000, which likely was attributable to a decrease in the number of plant retailers who stocked P obconica and the availability of primin-free varieties from 50% of suppliers.3 Furthermore, a study in the United States of 567 consecutive patch tests that included primin as part of standard screening found only 1 positive reaction, suggesting that routine patch testing for P obconica in the United States would have a low yield unless the patient has a relevant history.4
Cutaneous Presentation
Clinical features of P obconica–induced dermatitis include fingertip dermatitis, as well as facial, hand, and forearm dermatitis.6 Patients typically present with lichenification and fissuring of the fingertips; fingertip vesicular dermatitis; or linear erythematous streaks, vesicles, and bullae on the forearms, hands, and face. Vesicles and bullae can be hemorrhagic in patients with pompholyxlike lesions.7
Some patients have been reported to present with facial angioedema; the clinical diagnosis of CD can be challenging when facial edema is more prominent than eczema.6 Furthermore, in a reported case of P obconica CD, the patient’s vesicular hand dermatitis became pustular and spread to the face.8
Allergy Testing
Patch testing is performed with synthetic primin to detect allergens of P obconica in patients who are sensitive to them, which can be useful because Primula dermatitis can have variable presentations and cases can be missed if patch testing is not performed.9 Diagnostic mimics—herpes simplex, pompholyx, seborrheic dermatitis, and scabies—should be considered before patch testing.7
Prevention and Treatment
Preventive Measures—Ideally, once CD occurs in response to P obconica, handling of and other exposure to the plant should be halted; thus, prevention becomes the mainstay of treatment. Alternatively, when exposure is a necessary occupational hazard, nitrile gloves should be worn; allergenicity can be decreased by overwatering or introducing more primin-free varieties.3,10
Cultivating the plant outdoors during the winter in milder climates can potentially decrease sensitivity because allergen production is lowest during cold months and highest during summer.11 Because P obconica is commonly grown indoors, allergenicity can persist year-round.
Pharmacotherapy—Drawing on experience treating CD caused by other plants, acute and chronic P obconica CD are primarily treated with a topical steroid or, if the face or genitals are affected, with a steroid-sparing agent, such as tacrolimus.12 A cool compress of water, saline, or Burow solution (aluminum acetate in water) can help decrease acute inflammation, especially in the setting of vesiculation.13
Mild CD also can be treated with a barrier cream and lipid-rich moisturizer. Their effectiveness likely is due to increased hydration and aiding impaired skin-barrier repair.14
Some success in treating chronic CD also has been reported with psoralen plus UVA and UVB light therapy, which function as local immunosuppressants, thus decreasing inflammation.15
Final Thoughts
Contact dermatitis caused by P obconica is common in Europe but less common in the United States and therefore often is underrecognized. Avoiding contact with the plant should be strongly recommended to allergic persons. Primula obconica allergic CD can be treated with a topical steroid.
- Nan P, Shi S, Peng S, et al. Genetic diversity in Primula obconica (Primulaceae) from Central and South‐west China as revealed by ISSR markers. Ann Bot. 2003;91:329-333. doi:10.1093/AOB/MCG018
- Primula obconica “Libre Magenta” (Ob). The Royal Horticultural Society. Accessed February 14, 2023. https://www.rhs.org.uk/plants/131697/i-primula-obconica-i-libre-magenta-(ob)/details
- Connolly M, McCune J, Dauncey E, et al. Primula obconica—is contact allergy on the decline? Contact Dermatitis. 2004;51:167-171. doi:10.1111/J.0105-1873.2004.00427.X
- Mowad C. Routine testing for Primula obconica: is it useful in the United States? Am J Contact Dermat. 1998;9:231-233.
- Agrup C, Fregert S, Rorsman H. Sensitization by routine patch testing with ether extract of Primula obconica. Br J Dermatol. 1969;81:897-898. doi:10.1111/J.1365-2133.1969.TB15970.X
- Lleonart Bellfill R, Casas Ramisa R, Nevot Falcó S. Primula dermatitis. Allergol Immunopathol (Madr). 1999;27:29-31.
- Thomson KF, Charles-Holmes R, Beck MH. Primula dermatitis mimicking herpes simplex. Contact Dermatitis. 1997;37:185-186. doi:10.1111/J.1600-0536.1997.TB00200.X
- Tabar AI, Quirce S, García BE, et al. Primula dermatitis: versatility in its clinical presentation and the advantages of patch tests with synthetic primin. Contact Dermatitis. 1994;30:47-48. doi:10.1111/J.1600-0536.1994.tb00734.X
- Apted JH. Primula obconica sensitivity and testing with primin. Australas J Dermatol. 1988;29:161-162. doi:10.1111/J.1440-0960.1988.TB00390.X
- Aplin CG, Lovell CR. Contact dermatitis due to hardy Primula species and their cultivars. Contact Dermatitis. 2001;44:23-29. doi:10.1034/J.1600-0536.2001.440105.X
- Christensen LP, Larsen E. Direct emission of the allergen primin from intact Primula obconica plants. Contact Dermatitis. 2000;42:149-153. doi:10.1034/J.1600-0536.2000.042003149.X
- Esser PR, Mueller S, Martin SF. Plant allergen-induced contact dermatitis. Planta Med. 2019;85:528-534. doi:10.1055/A-0873-1494
- Levin CY, Maibach HI. Do cool water or physiologic saline compresses enhance resolution of experimentally-induced irritant contact dermatitis? Contact Dermatitis. 2001;45:146-150. doi:10.1034/J.1600-0536.2001.045003146.X
- M, Lindberg M. The influence of a single application of different moisturizers on the skin capacitance. Acta Derm Venereol. 1991;71:79-82.
- Levin CY, Maibach HI. Irritant contact dermatitis: is there an immunologic component? Int Immunopharmacol. 2002;2:183-189. doi:10.1016/S1567-5769(01)00171-0
- Nan P, Shi S, Peng S, et al. Genetic diversity in Primula obconica (Primulaceae) from Central and South‐west China as revealed by ISSR markers. Ann Bot. 2003;91:329-333. doi:10.1093/AOB/MCG018
- Primula obconica “Libre Magenta” (Ob). The Royal Horticultural Society. Accessed February 14, 2023. https://www.rhs.org.uk/plants/131697/i-primula-obconica-i-libre-magenta-(ob)/details
- Connolly M, McCune J, Dauncey E, et al. Primula obconica—is contact allergy on the decline? Contact Dermatitis. 2004;51:167-171. doi:10.1111/J.0105-1873.2004.00427.X
- Mowad C. Routine testing for Primula obconica: is it useful in the United States? Am J Contact Dermat. 1998;9:231-233.
- Agrup C, Fregert S, Rorsman H. Sensitization by routine patch testing with ether extract of Primula obconica. Br J Dermatol. 1969;81:897-898. doi:10.1111/J.1365-2133.1969.TB15970.X
- Lleonart Bellfill R, Casas Ramisa R, Nevot Falcó S. Primula dermatitis. Allergol Immunopathol (Madr). 1999;27:29-31.
- Thomson KF, Charles-Holmes R, Beck MH. Primula dermatitis mimicking herpes simplex. Contact Dermatitis. 1997;37:185-186. doi:10.1111/J.1600-0536.1997.TB00200.X
- Tabar AI, Quirce S, García BE, et al. Primula dermatitis: versatility in its clinical presentation and the advantages of patch tests with synthetic primin. Contact Dermatitis. 1994;30:47-48. doi:10.1111/J.1600-0536.1994.tb00734.X
- Apted JH. Primula obconica sensitivity and testing with primin. Australas J Dermatol. 1988;29:161-162. doi:10.1111/J.1440-0960.1988.TB00390.X
- Aplin CG, Lovell CR. Contact dermatitis due to hardy Primula species and their cultivars. Contact Dermatitis. 2001;44:23-29. doi:10.1034/J.1600-0536.2001.440105.X
- Christensen LP, Larsen E. Direct emission of the allergen primin from intact Primula obconica plants. Contact Dermatitis. 2000;42:149-153. doi:10.1034/J.1600-0536.2000.042003149.X
- Esser PR, Mueller S, Martin SF. Plant allergen-induced contact dermatitis. Planta Med. 2019;85:528-534. doi:10.1055/A-0873-1494
- Levin CY, Maibach HI. Do cool water or physiologic saline compresses enhance resolution of experimentally-induced irritant contact dermatitis? Contact Dermatitis. 2001;45:146-150. doi:10.1034/J.1600-0536.2001.045003146.X
- M, Lindberg M. The influence of a single application of different moisturizers on the skin capacitance. Acta Derm Venereol. 1991;71:79-82.
- Levin CY, Maibach HI. Irritant contact dermatitis: is there an immunologic component? Int Immunopharmacol. 2002;2:183-189. doi:10.1016/S1567-5769(01)00171-0
Practice Points
- Primula obconica is a household plant that can cause contact dermatitis (CD). Spent blossoms must be pinched off to keep the plant blooming, resulting in fingertip dermatitis.
- In the United States, P obconica is not a component of routine patch testing; therefore, it might be missed as the cause of an allergic reaction.
- Primin and miconidin are the principal allergens known to be responsible for causing P obconica dermatitis.
- Treatment of this condition is similar to the usual treatment of plant-induced CD: avoiding exposure to the plant and applying a topical steroid.