First line Anti-TB therapy with rifampicin, isoniazid, pyrazinamide, and ethambutol/streptomycin is very effective. However, major adverse reactions to antituberculous drugs can cause significant morbidity and mortality. Cutaneous adverse drug reaction (CADR) is one of the commonly observed major adverse events. This retrospective study looked at the cases of TB treated in Respiratory Unit, Penang Hospital from January 2004 to December 2005. Of 820 patients treated for active TB, 47 patients (25 females; 22 males) developed CADR (5.7%). CADRs observed include morbiliform rash (72.3%), erythema multiforme syndrome (8.5%), urticaria (8.5%) and others (which include exfoliative dermatitis and lichenoid eruption). Ninety-seven percent of events occurred within two months after the initial dose. Incidence rate of CADR among the first line anti-TB drugs, pyrazinamide was the commonest offending drug (2.38%), followed by streptomycin (1.45%), ethambutol (1.44%), rifampicin (1.23%) and isoniazid (0.98%). Various clinical characteristics of patients with CADR identified include Human Immunodeficiency Virus (HIV) infection (27.7%), polypharmacy (21.3%), elderly (19.1%), autoimmune disorders (6.4%), pre-existing renal impairment (4.3%), pre-existing liver disorders (4.3%). In conclusion, CADR is common and majority of cases occurred within two months after initiation of anti-TB treatment, particularly in HIV infected patients. Pyrazinamide is the commonest offending drug.
A careful drug history should be obtained from all patients with acute or chronic urticaria/angioedema, especially in the elderly. Although strictly comparable data are lacking, drug-induced urticaria appears to be more common in developed countries than in Malaysia, at least in a Hospital setting. Culprit drugs include antibiotics, analgesics and contrast media. Pseudoallergic drug-induced urticaria mimicks true allergic urticaria, but without an evident immunological basis, and is at least as common as the allergic type. In Malaysia, and in many other countries compulsory, ingredient labelling of 'traditional' medicines would do much to reduce the frequency of drug-induced urticaria.
Cutaneous adverse drug reactions (cADR) are common. However, only very few audits reported the clinical characteristics of cADR captured at district hospitals. We performed a 4-year audit on cADR reported to the Department of Pharmacy in Hospital Pakar Sultanah Fatimah between May 2012 and March 2016. It showed that the main adverse drug reaction (ADR) reporters were pharmacists (84.9%) where the majority of the reactions were clinical descriptions without dermatological diagnosis. Antibiotics (46.4%) were the commonest culprit drug followed by NSAIDs (22%). The most common reactions were immediate reactions, i.e. urticaria and angioedema contributing 55.7% of the cases; followed by maculopapular eruptions (41.8%). There were only six cases (1%) of severe cADR reported in this cohort. Reporting bias and the incomplete dermatological diagnosis were the main limitation of the reports.