1684. Clinical Profile and Outcome of Scrub Typhus-Related Acute Respiratory Distress Syndrome in Adults Presenting to a Tertiary Care Hospital in North India.

Background To study the clinical profile and outcome of adult patients presenting with Scrub typhus ARDS in emergency at our institute. Methods Prospective observational study which included 126 adult patients presenting to emergency department at, PGIMER Chandigarh, a tertiary care referral institute in northwestern India with acute febrile illness with ARDS (acute onset respiratory distress within one week of fever or new/worsening respiratory symptoms with PaO₂/FiO₂ ratio less than 300 with PEEP or CPAP more than 5 cm H₂O from January 2016 to December 2017.All the patients consenting for the study underwent detailed clinical evaluation and investigated for the etiology as per standard protocol followed at our institute with special emphasis to rule out tropical illnesses like scrub typhus, malaria, leptospirosis, dengue and H1N1 influenza. Patients were followed till discharge. Results Out of 126 patients eligible for the study, 45.2% were males and 54.8% were females. 47.6% were admitted in the monsoon/post-monsoon period. In addition to fever and dyspnea, cough (75.8%), hepatomegaly (56%), myalgia (63%), splenomegaly (31.3%), pedal edema (34.2%), pallor (40.4%), and vomiting (48.4%) were the common symptoms observed. Scrub typhus in 33.3%, followed by H1N1 influenza in 15.8%, co-infections in 12.6%, leptospirosis in (4.76%), dengue in (3.96%) and malaria in 3.17% of the patients, were the most common etiologies encountered. In 26.9% patients, no definite infective etiology could be found. Among the scrub typhus patients, 16 required ventilation. SOFA score of more than 6 was noted in 24 (57.14%) patients with scrub typhus as compared 9 (47.3%) patients with H1N1 infection. 12.1% of patients with scrub typhus succumbed to their illness when compared with 36.8% of patients with H1N1 infection. At admission in emergency female sex (P = 0.048), age less than 45 years, (P = 0.020), abdominal pain (P = 0.011), presence of hepatosplenomegaly (P = 0.001/0.010), thrombocytopenia <150,000 (P = 0.001), transaminitis (P = 0.00) were significant predictors of a diagnosis of scrub typhus when compared with a non-scrub typhus etiology of patients with fever and ARDS. Conclusion Scrub typhus is an important, treatable tropical infection causing ARDS especially in monsoon/post-monsoon seasons in Northwestern India. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]