Photodermatology, Photoimmunology & Photomedicine
LETTER TO THE EDITOR
Blistering psoriatic plaques during narrowband UVB phototherapy Caoimhe M. R. Fahy1, Ian McDonald1, Lynn Gaynor1, Gillian M. Murphy1, Niall Mulligan2, Patsy Lenane1 & Fergal J. Moloney1
1
National Photobiology Unit, Department of Dermatology, Mater Misericordiae University Hospital, Dublin, Ireland 2 Department of Pathology, Mater Misericordiae University Hospital, Dublin, Ireland.
Correspondence: Dr Fergal J. Moloney, National Photobiology Unit, Department of Dermatology, Mater Misericordiae University Hospital, Eccles Street, Dublin 7, Ireland. Tel: +35318545272 Fax: +35318034995 e-mail: [email protected]
Accepted for publication: 9 February 2015
bullae resolved within 48 h following twice-daily application of a moderately potent topical steroid. Phototherapy was continued with a reduction in dose increments to 10% and no further adverse events.
CASE 2 A 36-year-old male on his second course of TL-01 photototherapy developed a blistering eruption after his 28th treatment session. The blisters were mildly pruritic and occurred within psoriatic plaques on his right arm, left arm and back. Phototherapy was held until the bullae resolved and recommenced with dose increments decreased to 10%. After the 37th treatment session, two further blisters developed in psoriatic plaques on the upper limbs at which time treatment was discontinued.
Conflicts of interest: None declared.
To the Editor, Narrowband UVB or TL-01 phototherapy is an effective treatment for psoriasis (1). The emitted wavelength range (311–313 nm) is optimal for antipsoriatic activity (2). A rare side effect of TL-01 phototherapy is the development of blisters on psoriatic lesions, during a treatment course. Herein, we report four such cases which were identified in our institution over a 5-month period and review all reported cases in an effort to better understand the pathogenesis of this phenomenon.
CASE 1 A 23-year-old female with guttate psoriasis had received 18 treatments of TL-01 phototherapy with 20% incremental dosing as per standard protocol. Six hours after her 19th treatment session, she noted blistering within the margins of a treated psoriatic plaque on her left forearm. Her next TL-01 treatment was deferred and the ª 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd doi:10.1111/phpp.12167
CASE 3 A 59-year-old female had a history of four previous uneventful courses of TL-01 phototherapy for psoriasis. She developed a single bulla on a psoriatic plaque on the right hip after the 19th treatment session of TL-01 which resolved quickly. Further blistering occurred following her 22nd and 27th treatments despite reduction in dose increments initially to 10% and then 5%.
CASE 4 A 24-year-old male noted bullae within a psoriatic plaque on his left forearm after the 14th treatment of his 4th treatment course of TL-01 (Fig. 1). The bullae resolved with twice-daily application of a moderately potent topical steroid and emollients. Phototherapy was continued thereafter without further adverse events. No new medications preceded blistering in any of the four cases. Three of the four patients had prior, uneventful courses of TL-01. When the lesional blistering was noted by the patients, they did not have increased erythema or blistering in nonaffected skin. 167
Letter to the Editor
DISCUSSION
Fig 1. One to two centimetre, well-defined, intact bullae (arrowed) on a background psoriatic plaque on the left forearm.
Investigations, including autoimmune and porphyrin screens, were negative in each case. The patient in case 1 had a skin biopsy from a representative area of blistering. Histopathology showed an intraepidermal vesicular dermatitis with extensive suprabasilar epidermal necrosis and a mild, upper epidermal perivascular inflammatory infiltrate, with no eosinophils and no interface change. Direct immunofluoresence and PAS were negative. These changes were reported as consistent with a phototoxic reaction. In each case, blistering resolved with topical steroids and emollients and phototherapy was reintroduced with lower dose increments. All patients went on to complete their phototherapy. Three of the four were clear, or with minimal residual disease following treatment while one patient had his treatment discontinued due to lack of efficacy. The phototherapy unit in our institution has two TL-01 cabinets. The above cases occurred in both. A calibrated TL-01 International Light detector showed that there was less than 2% variation in irradiance across the 4 faces of the two whole body TL-01 cabinets. Since these index cases, no further episodes have been identified.
Bullae occurring on TL-01 phototherapy-treated psoriatic plaques are sufficiently rare or underreported, that their cause remains uncertain. This phenomenon was first described in 1992. The original report from Scotland identified four patients of 600 receiving TL - 01 phototherapy over a six-year period (3). Since then, a total of 11 cases have been recorded (3–5). All cases described have common features such as: bullae occuring on the psoriatic plaques or papules; the surrounding nonlesional skin being spared of bullae; negative autoimmune serology; negative porphyrin screens; negative direct immunofluoresence; similar histopathology; and the bullous eruption running a benign course, after resolution of which, phototherapy can be successfully resumed at lower doses (3–5). Except for the case report by Corey et al. (5), all patients received treatments with a minimal erythema dose, triweekly protocol. The clustering of cases in our institution over a 5month period prompted an initial review to ensure equipment malfunction or errors in dosimetry were not responsible. If, however, device malfunction was associated with blistering in these cases, it would likely occur on affected and nonaffected skin. Following on the initial cases, a proactive approach was taken, with patients receiving phototherapy asked to report any episodes of transient blistering. There have been no further episodes of blistering noted to date. Table 1 documents data from our patients and other reported cases (3–5) comparing patient age, gender, body site and timing when blistering occurred. There are no common variables that might indicate a treatment regimen or patient subgroup that are predisposed. It has been proposed that the treated plaques have a loss of photoprotection factors, such as the increase in stratum corneum thickness and pigmentation, which occurs in the surrounding skin during the treatment course. This may contribute to lesional blistering (3–5). Raising awareness of this adverse effect is important for those
Table 1. 11 additional cases of lesional blistering with TL-01 Study
M/F
George et al. Calzavara-Pinton et al. Corey et al. Fahy et al.
3F, 1M 2F, 4M 1M 2F, 2M
Age (yrs) 15–44 17–72 49 23–59
Prev TL-01 0–2 0 1–3
TX No. when blistered 11–23 6–28 14–37
Site UL (2), Trunk (2) Trunk (5), LL (1) Trunk, UL, LL UL (4), LL (1), Trunk (2)
UL, upper limbs; LL lower limbs. 168
Photodermatol Photoimmunol Photomed 2015; 31: 167–169 ª 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Letter to the Editor
delivering and receiving TL-01. It is possible that the blistering incidence is higher than reported and is ignored by patients due to the benign course and rapid
resolution of the bullae. Highlighting this side effect of TL-01 phototherapy may provoke further identification and investigation.
REFERENCES 1. Coven TR, Burack LH, Gilleaudeau R, Keogh M, Ozawa M, Krueger JG. Narrowband UV-B produces superior clinical and histopathological resolution of moderate-to-severe psoriasis in patients compared with broadband UVB. Arch Dermatol 1997; 133: 1514–1522. 2. Parrish JA, Jaenicke KF. Action spectrum for phototherapy of psoriasis. J Invest Dermatol 1981; 76: 359–362.
3. George SA, Ferguson J. Lesional blistering following narrow-band (TL-01) UVB phototherapy for psoriasis: a report of four cases. Br J Dermatol 1992; 127: 445– 446. 4. Calzavara-Pinton PG, Zane C, Candiago E, Facchetti F. Blisters on psoriatic lesions treated with TL-01 lamps. Dermatology 2000; 200: 115–119.
Photodermatol Photoimmunol Photomed 2015; 31: 167–169 ª 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
5. Corey K, Levin NA, Hure M, Deng A, Mailhot J. Eruption of bullae within psoriatic plaques: a rare adverse effect of narrow-band ultraviolet B (NB-UVB) phototherapy. Dermatol Online J 2012; 18: 3.
169
This document is a scanned copy of a printed document. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material.
LETTER TO THE EDITOR
Blistering psoriatic plaques during narrowband UVB phototherapy Caoimhe M. R. Fahy1, Ian McDonald1, Lynn Gaynor1, Gillian M. Murphy1, Niall Mulligan2, Patsy Lenane1 & Fergal J. Moloney1
1
National Photobiology Unit, Department of Dermatology, Mater Misericordiae University Hospital, Dublin, Ireland 2 Department of Pathology, Mater Misericordiae University Hospital, Dublin, Ireland.
Correspondence: Dr Fergal J. Moloney, National Photobiology Unit, Department of Dermatology, Mater Misericordiae University Hospital, Eccles Street, Dublin 7, Ireland. Tel: +35318545272 Fax: +35318034995 e-mail: [email protected]
Accepted for publication: 9 February 2015
bullae resolved within 48 h following twice-daily application of a moderately potent topical steroid. Phototherapy was continued with a reduction in dose increments to 10% and no further adverse events.
CASE 2 A 36-year-old male on his second course of TL-01 photototherapy developed a blistering eruption after his 28th treatment session. The blisters were mildly pruritic and occurred within psoriatic plaques on his right arm, left arm and back. Phototherapy was held until the bullae resolved and recommenced with dose increments decreased to 10%. After the 37th treatment session, two further blisters developed in psoriatic plaques on the upper limbs at which time treatment was discontinued.
Conflicts of interest: None declared.
To the Editor, Narrowband UVB or TL-01 phototherapy is an effective treatment for psoriasis (1). The emitted wavelength range (311–313 nm) is optimal for antipsoriatic activity (2). A rare side effect of TL-01 phototherapy is the development of blisters on psoriatic lesions, during a treatment course. Herein, we report four such cases which were identified in our institution over a 5-month period and review all reported cases in an effort to better understand the pathogenesis of this phenomenon.
CASE 1 A 23-year-old female with guttate psoriasis had received 18 treatments of TL-01 phototherapy with 20% incremental dosing as per standard protocol. Six hours after her 19th treatment session, she noted blistering within the margins of a treated psoriatic plaque on her left forearm. Her next TL-01 treatment was deferred and the ª 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd doi:10.1111/phpp.12167
CASE 3 A 59-year-old female had a history of four previous uneventful courses of TL-01 phototherapy for psoriasis. She developed a single bulla on a psoriatic plaque on the right hip after the 19th treatment session of TL-01 which resolved quickly. Further blistering occurred following her 22nd and 27th treatments despite reduction in dose increments initially to 10% and then 5%.
CASE 4 A 24-year-old male noted bullae within a psoriatic plaque on his left forearm after the 14th treatment of his 4th treatment course of TL-01 (Fig. 1). The bullae resolved with twice-daily application of a moderately potent topical steroid and emollients. Phototherapy was continued thereafter without further adverse events. No new medications preceded blistering in any of the four cases. Three of the four patients had prior, uneventful courses of TL-01. When the lesional blistering was noted by the patients, they did not have increased erythema or blistering in nonaffected skin. 167
Letter to the Editor
DISCUSSION
Fig 1. One to two centimetre, well-defined, intact bullae (arrowed) on a background psoriatic plaque on the left forearm.
Investigations, including autoimmune and porphyrin screens, were negative in each case. The patient in case 1 had a skin biopsy from a representative area of blistering. Histopathology showed an intraepidermal vesicular dermatitis with extensive suprabasilar epidermal necrosis and a mild, upper epidermal perivascular inflammatory infiltrate, with no eosinophils and no interface change. Direct immunofluoresence and PAS were negative. These changes were reported as consistent with a phototoxic reaction. In each case, blistering resolved with topical steroids and emollients and phototherapy was reintroduced with lower dose increments. All patients went on to complete their phototherapy. Three of the four were clear, or with minimal residual disease following treatment while one patient had his treatment discontinued due to lack of efficacy. The phototherapy unit in our institution has two TL-01 cabinets. The above cases occurred in both. A calibrated TL-01 International Light detector showed that there was less than 2% variation in irradiance across the 4 faces of the two whole body TL-01 cabinets. Since these index cases, no further episodes have been identified.
Bullae occurring on TL-01 phototherapy-treated psoriatic plaques are sufficiently rare or underreported, that their cause remains uncertain. This phenomenon was first described in 1992. The original report from Scotland identified four patients of 600 receiving TL - 01 phototherapy over a six-year period (3). Since then, a total of 11 cases have been recorded (3–5). All cases described have common features such as: bullae occuring on the psoriatic plaques or papules; the surrounding nonlesional skin being spared of bullae; negative autoimmune serology; negative porphyrin screens; negative direct immunofluoresence; similar histopathology; and the bullous eruption running a benign course, after resolution of which, phototherapy can be successfully resumed at lower doses (3–5). Except for the case report by Corey et al. (5), all patients received treatments with a minimal erythema dose, triweekly protocol. The clustering of cases in our institution over a 5month period prompted an initial review to ensure equipment malfunction or errors in dosimetry were not responsible. If, however, device malfunction was associated with blistering in these cases, it would likely occur on affected and nonaffected skin. Following on the initial cases, a proactive approach was taken, with patients receiving phototherapy asked to report any episodes of transient blistering. There have been no further episodes of blistering noted to date. Table 1 documents data from our patients and other reported cases (3–5) comparing patient age, gender, body site and timing when blistering occurred. There are no common variables that might indicate a treatment regimen or patient subgroup that are predisposed. It has been proposed that the treated plaques have a loss of photoprotection factors, such as the increase in stratum corneum thickness and pigmentation, which occurs in the surrounding skin during the treatment course. This may contribute to lesional blistering (3–5). Raising awareness of this adverse effect is important for those
Table 1. 11 additional cases of lesional blistering with TL-01 Study
M/F
George et al. Calzavara-Pinton et al. Corey et al. Fahy et al.
3F, 1M 2F, 4M 1M 2F, 2M
Age (yrs) 15–44 17–72 49 23–59
Prev TL-01 0–2 0 1–3
TX No. when blistered 11–23 6–28 14–37
Site UL (2), Trunk (2) Trunk (5), LL (1) Trunk, UL, LL UL (4), LL (1), Trunk (2)
UL, upper limbs; LL lower limbs. 168
Photodermatol Photoimmunol Photomed 2015; 31: 167–169 ª 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Letter to the Editor
delivering and receiving TL-01. It is possible that the blistering incidence is higher than reported and is ignored by patients due to the benign course and rapid
resolution of the bullae. Highlighting this side effect of TL-01 phototherapy may provoke further identification and investigation.
REFERENCES 1. Coven TR, Burack LH, Gilleaudeau R, Keogh M, Ozawa M, Krueger JG. Narrowband UV-B produces superior clinical and histopathological resolution of moderate-to-severe psoriasis in patients compared with broadband UVB. Arch Dermatol 1997; 133: 1514–1522. 2. Parrish JA, Jaenicke KF. Action spectrum for phototherapy of psoriasis. J Invest Dermatol 1981; 76: 359–362.
3. George SA, Ferguson J. Lesional blistering following narrow-band (TL-01) UVB phototherapy for psoriasis: a report of four cases. Br J Dermatol 1992; 127: 445– 446. 4. Calzavara-Pinton PG, Zane C, Candiago E, Facchetti F. Blisters on psoriatic lesions treated with TL-01 lamps. Dermatology 2000; 200: 115–119.
Photodermatol Photoimmunol Photomed 2015; 31: 167–169 ª 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
5. Corey K, Levin NA, Hure M, Deng A, Mailhot J. Eruption of bullae within psoriatic plaques: a rare adverse effect of narrow-band ultraviolet B (NB-UVB) phototherapy. Dermatol Online J 2012; 18: 3.
169
This document is a scanned copy of a printed document. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material.
