Dengue Mimickers: Which Clinical Conditions Can Resemble Dengue Fever?

Abstract

Epidemics and outbreaks caused by the dengue virus pose risks to populations and have high mortality rates, causing burdens and economic costs worldwide. Brazil recently experienced an explosive increase in the number of dengue cases and fatalities. Dengue is an acute febrile illness that can progress to severe forms. It affects more than 100 countries, presenting ongoing challenges in Brazil and globally since its identification. Other conditions may be overlooked or mistaken for dengue. The most important differential diagnoses are other infectious diseases and rheumatological, hematological, gastroenterological, and neurological disorders. In this article, we discuss the primary differential diagnoses of dengue and offer a literature review highlighting the key clinical differences among clinicians. This review emphasizes the critical importance of differentiating dengue fever from infectious diseases such as meningococcemia and malaria and autoimmune and rheumatological conditions such as systemic lupus erythematosus to ensure timely and appropriate management.

FIGURE 1:. A. Meningococcal purpura fulminans lesions on the feet. B. Classical meningococcal skin lesions with a violaceous hue and petechiae on the lower limbs. C and D. Petechial lesions on the hands and feet in a 19-year-old patient with meningococcemia, initially misdiagnosed as dengue (DEN). Source: Personal archive of Dr. Pedro Bessa.

FIGURE 2:. A. A 26-year-old female patient with a clinical presentation suggestive of DEN, including fever, rash, myalgia, asthenia, and adynamia lasting 3 days. During admission, circular erythematous lesions were noted, accompanied by a history of multiple kissing bug bites on the arm. Examination of the insect’s feces subsequently revealed the presence of Trypanosoma cruzi, confirming the diagnosis of acute Chagas disease. B. A 48-year-old female patient from a rural mountainous region in northeastern Brazil, presented with fever, upper limb arthralgia, myalgia, and a rash on the trunk and breasts. Physical examination revealed numerous erythematous lesions on the trunk, back, and breasts, some exhibiting a crusted appearance. Serological testing for Brazilian spotted fever confirmed the diagnosis by demonstrating a fourfold increase in IgG titers.

FIGURE 3:. A. Still’s Disease with its characteristic, well-defined salmon-colored rash. B. Typical exanthema in DEN, demonstrating blanching under digital pressure. C. Petechial lesions on the patient’s arms. Source: Personal archive of Dr. Jobson Lopes.