A Carr1, R Penny, D A Cooper. 1. Centre for Immunology, St Vincent's Hospital, Sydney, Australia.
Abstract
OBJECTIVE: This study was undertaken to determine whether patients infected with HIV and with prior hypersensitivity to trimethoprim-sulphamethoxazole (TMP-SMX) can be rechallenged successfully with TMP-SMX, what factors predict successful rechallenge, and whether hypersensitivity is due to TMP or to SMX. DESIGN: A prospective, open study. SETTING: A tertiary referral hospital. PATIENT: Thirty-one HIV-infected patients with a history of non-life-threatening hypersensitivity to TMP-SMX. INTERVENTIONS: Patients received TMP (300 mg twice a week) for 2 weeks and, where no major reaction occurred, subsequently with TMP-SMX (160 and 800 mg per tablet, one tablet two times a day, twice a week). Patients who developed significant and persistent hypersensitivity ceased SMX and were subsequently challenged with TMP-dapsone (300 and 100 mg, respectively, twice a week). MAIN OUTCOME MEASURES: That rechallenge is more likely to be successful in those with advanced HIV disease. RESULTS: Five out of 31 (16%) patients developed hypersensitivity to TMP, and two ceased TMP as a result. Fifteen of the 26 (58%) patients who received subsequent TMP-SMX developed hypersensitivity, 12 of whom ceased TMP-SMX because of this reaction. Hypersensitivity to TMP-SMX was significantly less common in those with a CD4+ cell count < 20 x 10(6)/l than in those with a CD4+ cell count > 20 x 10(6)/l (31 versus 85%; P = 0.03). Hypersensitivity to TMP-dapsone occurred in two out of nine patients with hypersensitivity to TMP-SMX on rechallenge. One patient developed transient dyspnoea following a dose of SMX, but no other serious adverse drug reaction occurred. CONCLUSIONS: Rechallenge with TMP-SMX appears safe in HIV-infected patients with a history of non-life-threatening hypersensitivity and is most likely to be successful in patients with a low CD4+ lymphocyte count. The data suggest a low rate cross-hypersensitivity between SMX and dapsone, at least at the doses used.
OBJECTIVE: This study was undertaken to determine whether patients infected with HIV and with prior hypersensitivity to trimethoprim-sulphamethoxazole (TMP-SMX) can be rechallenged successfully with TMP-SMX, what factors predict successful rechallenge, and whether hypersensitivity is due to TMP or to SMX. DESIGN: A prospective, open study. SETTING: A tertiary referral hospital. PATIENT: Thirty-one HIV-infectedpatients with a history of non-life-threatening hypersensitivity to TMP-SMX. INTERVENTIONS:Patients received TMP (300 mg twice a week) for 2 weeks and, where no major reaction occurred, subsequently with TMP-SMX (160 and 800 mg per tablet, one tablet two times a day, twice a week). Patients who developed significant and persistent hypersensitivity ceased SMX and were subsequently challenged with TMP-dapsone (300 and 100 mg, respectively, twice a week). MAIN OUTCOME MEASURES: That rechallenge is more likely to be successful in those with advanced HIV disease. RESULTS: Five out of 31 (16%) patients developed hypersensitivity to TMP, and two ceased TMP as a result. Fifteen of the 26 (58%) patients who received subsequent TMP-SMX developed hypersensitivity, 12 of whom ceased TMP-SMX because of this reaction. Hypersensitivity to TMP-SMX was significantly less common in those with a CD4+ cell count < 20 x 10(6)/l than in those with a CD4+ cell count > 20 x 10(6)/l (31 versus 85%; P = 0.03). Hypersensitivity to TMP-dapsone occurred in two out of nine patients with hypersensitivity to TMP-SMX on rechallenge. One patient developed transient dyspnoea following a dose of SMX, but no other serious adverse drug reaction occurred. CONCLUSIONS: Rechallenge with TMP-SMX appears safe in HIV-infectedpatients with a history of non-life-threatening hypersensitivity and is most likely to be successful in patients with a low CD4+ lymphocyte count. The data suggest a low rate cross-hypersensitivity between SMX and dapsone, at least at the doses used.
Authors: Ana Alfirevic; Anne C Stalford; F Javier Vilar; Ed G L Wilkins; B Kevin Park; Munir Pirmohamed Journal: Br J Clin Pharmacol Date: 2003-02 Impact factor: 4.335