Dengue with Scrub Typhus Coinfection in Northern India

Background: Amongst the many vector and water-borne diseases prevalent in tropics, dengue occupies a prominent place. Dengue epidemics are frequent and at times, during such epidemic, coinfections may occur causing diagnostic dilemmas.

Case Report: A 36 years old lady, from a rural background, presented during the 2019 dengue epidemic with fever, vomiting, and non-colicky abdominal pain. The evaluation showed hepatosplenomegaly, leukocytosis, and thrombocytopenia. The investigations confirmed the diagnosis and she was treated conservatively as a case of dengue with warning signs. A longer than anticipated duration of fever and clinical deterioration prompted reassessment, which revealed the presence of an eschar over the right upper thigh. The Weil-Felix test using Proteus OX-K stain was positive at a titer of 1:320. Following treatment with oral doxycycline, she showed rapid defervescence and clinical improvement.

Conclusions: Coinfection with scrub typhus is rare with dengue. If left untreated, it adversely affects the outcome. The key to diagnosing such coinfections includes a high index of suspicion, repeated clinical examination, and the knowledge of local endemicity.