773 RESULTS OF INITIAL AND MAINTENANCE TREATMENT
hypersensitivity to dithranol (almost always temporary), and experience some treatment failures. The joint Newcastle/London report does not tell us the we
do
encounter
length of the remissions obtained after successful clearing of the psoriasis. Workers in other centres have stated that recurrences of psoriasis are relatively common after p.u.v.A. treatment, and that many patients require booster treatments every two weeks, or even weekly, for an indefinite period to control their psoriasis. This significantly increases the amount of exposure to long-wave ultraviolet light, with its attendant potential hazards. The conclusion of the report that "P.U.V.A. cannot be recommended as the first line of treatment" is in our present state of ignorance of long-term effects, most appropriate, and so also is the recommendation that the use of P.U.V.A. should be limited to a few centres until more is known of its long-term effects. It would be tragic if we provoked skin cancer in a large number of patients as a result of treating them for a disabling but relatively benign disease. Victoria General Hospital, Halifax, Nova Scotia, Canada
D. R. S. HOWELL
ULTRAVIOLET B PHOTOTHERAPY FOR PSORIASIS IN SUNLIGHT-RESPONSIVE PATIENTS
*Drop-outs from treatment (see text). tEvery 4 days.
SIR,-For some years now, patients with psoriasis have been treated with P.u.v.A.-i.e., oral administration of a photoac tive drug (8-methoxypsoralen) followed by exposure to longwave ultraviolet-A light (320-400 nm).1.2 During P.U.V.A. therapy the patient must protect eyes and skin from sunlight after treatment and practise contraception. Ultraviolet B phototherapy is now attracting attention. In experiments with ultraviolet in the B range (313 nm) without photoactive drugs Fischer3 obtained good results in cases with small psoriatic lesions. We have obtained promising results with U.V.B. phototherapy in fifteen selected patients with long-standing and stable psoriasis. The criterion for selection was that the psoriasis had repeatedly shown striking improvement after sunbathing. We used a panel of twelve Philips TL-12 40 W fluorescent tubes; irradiance at 50cm was 3-1mW/cm2 of 280-380 nm, peaking at 305 nm. Before treatment, light tests were carried out with the light panel to determine the minimal erythemal dose (M.E.D.) for two areas, the back and one lower leg. The U.V.B. dose used for the first treatment was equal to the highest lighttest dose that did not induce redness. Since the M.E.D. was definitely lower for the back than for the legs in all patients an additional irradiation was given on the lower legs and the elbows during the treatment in both the initial and the main-
range
phases. The dosage was increased by 30% per session unless erythema developed. The longest exposure-time for each side of the body, including the additional irradiation of lower legs and elbows, was 30 min (5-55 J/cm2) during the initial phase and 10 min (1-85 J/cm2) during the maintenance phase. During the initial (clearing) phase, four irradiations were given weekly, the total number ranging from 15 to 30 (mean 23) (see table). Thirteen of the fifteen patients showed a clearance of 80-100% of the psoriatic plaques relative to the pretreatment state, except on the scalp. The results could be maintained by administering one irradiation every 1-5 weeks (mean once every 14 days) for 6-40 weeks (mean 21 weeks). Three patients were dropped: patient 15 was found to be an alcoholic and in patients 13 and 14 a tendency to rapid relapse required a more frequent irradiation than was considered justified. Like Fischer,3 we found that the wavelengths in the U.V.B.
tenance
1
Parrish, J A., Fitzpatrick, T. B., Tanenbaum, L., Pathak, M. A. New Engl. J Med 1974, 291, 1207. 2 Rogers, S., Marks, J., Shuster, S., Briffa, D. V., Warin, A., Greaves, M. Lancet, 1979, i, 455 3 Fischer, T. Acta dermatovener. 1976, 56, 473.
(290-320 nm) are very effective for the treatment of psoriasis. The high therapeutic scores, which could generally be sustained by the maintenance treatment, are attributed to two factors-the selection of the patients, based on rapid response of the psoriasis to sunlight, and the method of irradiation, particularly the light tests for two areas, which resulted in the inclusion of an additional irradiation on the lower legs and elbows. The advantages of u.v.B. therapy over P.U.V.A. treatment include the avoidance of oral administration of photosensitisers (and the precautions that that aspect of therapy entail), the shorter exposure-times, and the possibility of home treatment with a simplified light panel. However, just as for the P.U.V.A. treatment, the long-term risk-benefit ratio (oncogenic aspects) must be extensively investigated before this kind of treatment can be recommended for use on a large scale. Department of Dermatology, University Hospital, Leiden, Netherlands
J. BOER A. A. SCHOTHORST D. SUURMOND
FAST GLYCOSYLATION OF HÆMOGLOBIN
Sm,—Dr Svendsen and his colleagues (March 17, p. 603) report dissociation of HbA1c in one patient within 12 h of control of hyperglycasmia. They suggest that glycosylation of HbA is a rapidly reversible process and that estimation of glycosylated haemoglobin is thus of limited clinical value. We agree that decreases of glycosylated haemoglobin can be rapid but disagree with the suggestion that clinically significant changes occur within a matter of hours. We suggest a clinically significant decrease in HbA, is unlikely to happen in less than a week. To determine how quickly HbA1 can fall we studied eight newly diagnosed insulin-dependent diabetics serially for 3 weeks. HbAl was estimated weekly and, in two patients (cases 1 and 2), HbA1 was measured daily for the first week. HbA1 was measured by macrocolumn chromatographic technique. All the patients were in hospital for the first week. On presentation every patient had 2- glycosuria and heavy ketonuria with a mean blood-glucose of 17.5 mmol/I (range 13-1—29-0; 1 mmol/1=18 mg/dl). Subsequent random morning blood-glucoses at the time of HbA1 estimations were all less than 10-5mmol/1, and urine tests done four times daily averaged less than 2 except in case 3 (average 1’). Results of are shown in the table. All patients showed
HbA1
hypersensitivity to dithranol (almost always temporary), and experience some treatment failures. The joint Newcastle/London report does not tell us the we
do
encounter
length of the remissions obtained after successful clearing of the psoriasis. Workers in other centres have stated that recurrences of psoriasis are relatively common after p.u.v.A. treatment, and that many patients require booster treatments every two weeks, or even weekly, for an indefinite period to control their psoriasis. This significantly increases the amount of exposure to long-wave ultraviolet light, with its attendant potential hazards. The conclusion of the report that "P.U.V.A. cannot be recommended as the first line of treatment" is in our present state of ignorance of long-term effects, most appropriate, and so also is the recommendation that the use of P.U.V.A. should be limited to a few centres until more is known of its long-term effects. It would be tragic if we provoked skin cancer in a large number of patients as a result of treating them for a disabling but relatively benign disease. Victoria General Hospital, Halifax, Nova Scotia, Canada
D. R. S. HOWELL
ULTRAVIOLET B PHOTOTHERAPY FOR PSORIASIS IN SUNLIGHT-RESPONSIVE PATIENTS
*Drop-outs from treatment (see text). tEvery 4 days.
SIR,-For some years now, patients with psoriasis have been treated with P.u.v.A.-i.e., oral administration of a photoac tive drug (8-methoxypsoralen) followed by exposure to longwave ultraviolet-A light (320-400 nm).1.2 During P.U.V.A. therapy the patient must protect eyes and skin from sunlight after treatment and practise contraception. Ultraviolet B phototherapy is now attracting attention. In experiments with ultraviolet in the B range (313 nm) without photoactive drugs Fischer3 obtained good results in cases with small psoriatic lesions. We have obtained promising results with U.V.B. phototherapy in fifteen selected patients with long-standing and stable psoriasis. The criterion for selection was that the psoriasis had repeatedly shown striking improvement after sunbathing. We used a panel of twelve Philips TL-12 40 W fluorescent tubes; irradiance at 50cm was 3-1mW/cm2 of 280-380 nm, peaking at 305 nm. Before treatment, light tests were carried out with the light panel to determine the minimal erythemal dose (M.E.D.) for two areas, the back and one lower leg. The U.V.B. dose used for the first treatment was equal to the highest lighttest dose that did not induce redness. Since the M.E.D. was definitely lower for the back than for the legs in all patients an additional irradiation was given on the lower legs and the elbows during the treatment in both the initial and the main-
range
phases. The dosage was increased by 30% per session unless erythema developed. The longest exposure-time for each side of the body, including the additional irradiation of lower legs and elbows, was 30 min (5-55 J/cm2) during the initial phase and 10 min (1-85 J/cm2) during the maintenance phase. During the initial (clearing) phase, four irradiations were given weekly, the total number ranging from 15 to 30 (mean 23) (see table). Thirteen of the fifteen patients showed a clearance of 80-100% of the psoriatic plaques relative to the pretreatment state, except on the scalp. The results could be maintained by administering one irradiation every 1-5 weeks (mean once every 14 days) for 6-40 weeks (mean 21 weeks). Three patients were dropped: patient 15 was found to be an alcoholic and in patients 13 and 14 a tendency to rapid relapse required a more frequent irradiation than was considered justified. Like Fischer,3 we found that the wavelengths in the U.V.B.
tenance
1
Parrish, J A., Fitzpatrick, T. B., Tanenbaum, L., Pathak, M. A. New Engl. J Med 1974, 291, 1207. 2 Rogers, S., Marks, J., Shuster, S., Briffa, D. V., Warin, A., Greaves, M. Lancet, 1979, i, 455 3 Fischer, T. Acta dermatovener. 1976, 56, 473.
(290-320 nm) are very effective for the treatment of psoriasis. The high therapeutic scores, which could generally be sustained by the maintenance treatment, are attributed to two factors-the selection of the patients, based on rapid response of the psoriasis to sunlight, and the method of irradiation, particularly the light tests for two areas, which resulted in the inclusion of an additional irradiation on the lower legs and elbows. The advantages of u.v.B. therapy over P.U.V.A. treatment include the avoidance of oral administration of photosensitisers (and the precautions that that aspect of therapy entail), the shorter exposure-times, and the possibility of home treatment with a simplified light panel. However, just as for the P.U.V.A. treatment, the long-term risk-benefit ratio (oncogenic aspects) must be extensively investigated before this kind of treatment can be recommended for use on a large scale. Department of Dermatology, University Hospital, Leiden, Netherlands
J. BOER A. A. SCHOTHORST D. SUURMOND
FAST GLYCOSYLATION OF HÆMOGLOBIN
Sm,—Dr Svendsen and his colleagues (March 17, p. 603) report dissociation of HbA1c in one patient within 12 h of control of hyperglycasmia. They suggest that glycosylation of HbA is a rapidly reversible process and that estimation of glycosylated haemoglobin is thus of limited clinical value. We agree that decreases of glycosylated haemoglobin can be rapid but disagree with the suggestion that clinically significant changes occur within a matter of hours. We suggest a clinically significant decrease in HbA, is unlikely to happen in less than a week. To determine how quickly HbA1 can fall we studied eight newly diagnosed insulin-dependent diabetics serially for 3 weeks. HbAl was estimated weekly and, in two patients (cases 1 and 2), HbA1 was measured daily for the first week. HbA1 was measured by macrocolumn chromatographic technique. All the patients were in hospital for the first week. On presentation every patient had 2- glycosuria and heavy ketonuria with a mean blood-glucose of 17.5 mmol/I (range 13-1—29-0; 1 mmol/1=18 mg/dl). Subsequent random morning blood-glucoses at the time of HbA1 estimations were all less than 10-5mmol/1, and urine tests done four times daily averaged less than 2 except in case 3 (average 1’). Results of are shown in the table. All patients showed
HbA1
