विवरण
Dengue and scrub typhus is endemic in many parts of India and Asia Pacific region and is considered to be a major cause of acute undifferentiated febrile illness. It is difficult to differentiate both the infections at their initial presentation as they share similar clinico-epidemiological features.
Mosquito-borne infection, dengue is caused by one of the four dengue virus serotypes belonging to the genus Flavivirus. Despite providing supportive management, mortality rates due to dengue shock syndrome (DSS) and dengue hemorrhagic fever ranges from 3% to 11%. Scrub typhus is caused by Gram-negative intracellular bacterium, Orientia tsutsugamushi. It is associated with a 14%-20% mortality rate due to delay in diagnosis and initiation of antibiotic therapy. Hence, early detection is crucial in the management of these infections and can improve patient outcomes.
सारांश
- Dengue is a viral infection caused by the dengue virus, with four serotypes (DEN1-4) important for human infection. It is transmitted through the bite of Aedes aegypti mosquitoes, which also transmit yellow fever, Zika, and chikungunya viruses. This mosquito is a daytime feeder and breeds in clean water, making urban environments conducive to its spread.
- The clinical classification of dengue has evolved. Earlier classifications distinguished undifferentiated fever, classic dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. The current WHO classification simplifies it to dengue with or without severe features, based on warning signs like plasma leakage, bleeding, altered consciousness, severe gastrointestinal involvement, and organ impairment.
- Diagnosis involves detecting the virus or antibodies. In the first 5-6 days of illness, the dengue NS1 antigen test or PCR is used. After this period, antibody tests (IgM) are more reliable. Treatment is primarily supportive, focusing on hydration and avoiding NSAIDs, which can worsen bleeding. Blood transfusions are given only for overt bleeding.
- Scrub typhus is a bacterial infection caused by Orientia tsutsugamushi, transmitted by the bite of trombiculid mites. Patients typically present with fever, rash, and myalgia. Complications can include acute lung injury, renal failure, and liver dysfunction. Diagnosis is aided by finding an eschar at the site of the mite bite.
- Laboratory diagnosis involves PCR in the early phase and IgM antibody detection later. The treatment of choice is doxycycline, typically resulting in rapid fever resolution within 24-48 hours. In pregnant women, azithromycin is used. Prevention focuses on avoiding mite bites by wearing protective clothing and using repellents.
- The WHO case definition includes a primary skin ulcer (eschar) followed by fever, headache, sweating, and conjunctival injection. Rapid fever deference following tetracycline therapy strongly suggests a rickettsial etiology. Eschar may be absent in some geographical areas or cases of frequent reinfection, and rash may be overlooked in patients with dark skin.
नमूना प्रमाण पत्र
वक्ताओं के बारे में
टिप्पणियाँ
टिप्पणियाँ
टिप्पणी करने के लिए आपको लॉगिन होना होगा।