title: Chest radiographic manifestations of scrub typhus.
abstract: OBJECTIVE
  Respiratory system involvement in scrub typhus is seen in 20-72% of patients. In endemic areas, good understanding and familiarity with the various radiologic findings of scrub typhus are essential in identifying pulmonary complications.
  
  
  METHODS
  Patients admitted to a tertiary care center with scrub typhus between October 2012 and September 2013 and had a chest X ray done were included in the analysis. Details and radiographic findings were noted and factors associated with abnormal X-rays were analyzed.
  
  
  RESULTS
  The study cohort contained 398 patients. Common presenting complaints included fever (100%), generalized myalgia (83%), headache (65%), dyspnea (54%), cough (24.3%), and altered sensorium (14%). Almost half of the patients (49.4%) had normal chest radiographs. Common radiological pulmonary abnormalities included pleural effusion (14.6%), acute respiratory distress syndrome (14%), airspace opacity (10.5%), reticulonodular opacities (10.3%), peribronchial thickening (5.8%), and pulmonary edema (2%). Cardiomegaly was noted in 3.5% of patients. Breathlessness, presence of an eschar, platelet counts of <20,000 cells/cumm, and total serum bilirubin >2 mg/dL had the highest odds of having an abnormal chest radiograph. Patients with an abnormal chest X-ray had a higher requirement of noninvasive ventilation (odds ratio [OR]: 13.98; 95% confidence interval CI: 5.89-33.16), invasive ventilation (OR: 18.07; 95% CI: 6.42-50.88), inotropes (OR: 8.76; 95% CI: 4.35-17.62), higher involvement of other organ systems, longer duration of hospital stay (3.18 ± 3 vs. 7.27 ± 5.58 days; P< 0.001), and higher mortality (OR: 4.63; 95% CI: 1.54-13.85).
  
  
  CONCLUSIONS
  Almost half of the patients with scrub typhus have abnormal chest radiographs. Chest radiography should be included as part of basic evaluation at presentation in patients with scrub typhus, especially in those with breathlessness, eschar, jaundice, and severe thrombocytopenia.
authors.affiliation: Department of Emergency Medicine, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Kpp
authors.initials: K
authors.lastname: Abhilash
authors.affiliation: Department of Radio-Diagnosis, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: P R
authors.initials: PR
authors.lastname: Mannam
authors.affiliation: Department of Emergency Medicine, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: K
authors.initials: K
authors.lastname: Rajendran
authors.affiliation: Department of Radio-Diagnosis, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: R A
authors.initials: RA
authors.lastname: John
authors.affiliation: Department of Biostatistics, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: P
authors.initials: P
authors.lastname: Ramasami
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003371:Cough / Q000209:etiology; D004417:Dyspnea / Q000209:etiology; D005260:Female; D005334:Fever / Q000209:etiology; D006261:Headache / Q000209:etiology; D006760:Hospitalization; D006801:Humans; D008171:Lung Diseases / Q000150:complications / Q000175:diagnosis / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013902:Radiography, Thoracic / Q000379:methods*; D012128:Respiratory Distress Syndrome; D012612:Scrub Typhus / Q000175:diagnosis / Q000000981:diagnostic imaging*