Dear Editor, We read with great interest the case report by Finsterer and Mehri,1 detailing a rare and intriguing clinical scenario wherein a 61-year-old male developed type A aortic dissection (AD) involving the right common carotid artery following two decades of continuous dapsone therapy for chronic pruritic bullous eczema. This case report has fascinated us in terms of novelty—a rare case of association of long-term dapsone therapy with type A aortic dissection. We found your attempt to link dapsone with aortic dissection appreciable. The case is presented with commendable detail, covering the patient’s clinical presentation, radiological findings, management, and following complications such as ischemic stroke and seizure. The established association between fluoroquinolones and aortic aneurysmal disease has been used by the authors to provide a parallel explanation with dapsone. Even though there is no direct evidence, we still cannot ignore it as it might form a signal for further vigilance process. The causality assessed by us as per the WHO UMC scale is found to have a possible causal relationship with the suspected drug—taking into consideration the time to event relationship of drug and disease, lack of de-challenge and re-challenge, and inability to rule out the underlying disease. Also, applying the Naranjo causality assessment scale, a score of 2 was obtained—due to a lack of previous conclusive report, presence of alternative causes like underlying disease, and age of the patient. Although causality found a possible relationship, it is difficult to establish a direct link between the adverse event and the drug. This event was considered a severe adverse event as per Hartwig’s severity assessment scale. Even though family history for cardiac disease is not present, details regarding genetic diseases and information regarding the presence or absence of a bicuspid valve are crucial in determining the causality in this case. Apart from the above, the patient’s age, smoking, and dyslipidemia are strong risk factors associated with AD.2,3 Inflammatory causes of AD, like Takayasu arteritis, Giant cell arteritis, IgG4 disease, Behcet’s disease, and systemic lupus erythematosus, in this case, needed to be ruled out to determine the causal association with dapsone.4 Long-term dapsone use for bullous-related diseases includes bullous systemic lupus erythematosus (BSLE) and linear IgA bullous dermatosis (LABD).5 Based on the nonspecific diagnosis provided in the case report, we feel that there is a possibility of BSLE as a differential diagnosis that needs to be ruled out. The systemic disease of BSLE, i.e., SLE may have led to the AD.6 Being a single report, the findings cannot be generalized, and the observed association of AD with dapsone may be idiosyncratic or coincidental, underscoring the need for population-level studies or case series before coming to a conclusion. This case report is a significant contribution to the literature due to its originality. While the hypothesis linking dapsone to AD merits further investigation, the evidence remains preliminary. Primary care clinicians are the first point of contact for a patient in rural and semi-urban livelihoods. Their role in assessing the cardiovascular status of patients on long-term dapsone therapy can contribute significantly to prevent the occurrence of AD if the case may be. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Joseph et al. (Thu,) studied this question.