Reply

Sir—Drs. Toerner and Cvetkovich raise important concerns related to the differential diagnosis of Kawasaki-like syndromes in adult patients infected with HIV [1]. It is critical that hypersensitivity reactions to the multitude of HIV-related medications be at the top of the differential diagnosis for patients who present with a rash, fever, and other constitutional complaints. This is especially true for patients receiving abacavir, because of the severe and potentially fatal nature of that hypersensitivity reaction. That said, it is important to clarify several issues related to the clinical presentations of the 2 patients described in our article, because the case reports were simplified to be concise.

At the time of presentation, patient 1 had not received any antiretroviral therapy for 1 year. The regimen chosen (stavudine, abacavir, ritonavir, and saquinavir) was a new salvage regimen. The patient had never taken abacavir, ritonavir, or saquinavir as components of any previous antiretroviral regimen dating back 7 years. The initial fever of his Kawasaki-like syndrome occurred 48 h after abacavir treatment was initiated. He was evaluated in our clinic the next morning for the possibility of an abacavir hypersensitivity reaction. Treatment with abacavir was continued because it was felt that a hypersensitivity reaction after taking four 300-mg abacavir tablets was unlikely in the absence of any prior exposure to abacavir.

One week later, the patient again presented to our clinic with continued fever, sore throat, rash, abdominal pain, nausea, and other symptoms, and he was initially given the diagnosis of abacavir hypersensitivity reaction. Antiretroviral medications were stopped, methylprednisolone was started, and the patient was warned never to take abacavir again. Forty-eight hours later, he was given the diagnosis of Kawasaki-like syndrome and treated with intravenous immunoglobulin because features of his clinical presentation were unusual for a drug reaction: the principal atypical feature was markedly swollen and painful hands and feet. To our knowledge, this symptom has not been described in patients with hypersensitivity reactions to abacavir; it is a rare finding in patients with adverse drug reactions [2, 3]. Even though patient 1 was treated for Kawasaki-like syndrome, it was emphasized to him that he should never take abacavir again. He had originally been reluctant to begin abacavir treatment because of the hypersensitivity issue. A thorough history revealed that patient 1 was receiving no antiretroviral therapy of any kind when he relapsed with a Kawasaki-like syndrome 5 months later.

Patient 2 has never been given a prescription for abacavir and, when a thorough history was determined, she also denied taking any medications other than dapsone and clarithromycin. After she recovered from the acute phase of the Kawasaki-like syndrome, treatment with those 2 medications was restarted without any adverse events.

We believe that patient 1 and patient 2 each had an idiopathic syndrome with features similar to pediatric Kawasaki disease, which we referred to as a Kawasaki-like syndrome. Since publication of our report, we have been made aware of 4 additional cases of HIV-infected adult patients with Kawasaki-like syndromes. Three of the 4 patients were treated with intravenous immunoglobulin, and each had a prompt clinical response ([4]; R. B. Porwancher, personal communication). It is important to apply the clinical diagnostic criteria for Kawasaki disease, as discussed in detail in our article, and to exclude drug reactions and opportunistic infections before giving an HIV-infected patient a diagnosis of Kawasaki-like syndrome. We support the call of Drs. Toerner and Cvetkovich for caution in ruling out adverse drug reactions to abacavir before attributing a febrile illness with rash and constitutional symptoms to a Kawasaki-like syndrome.