Scrub typhus: an unrecognized threat in South India - clinical profile and predictors of mortality.
Scrub typhus is an important cause of acute undifferentiated febrile illnesses in the Indian subcontinent. Delay in diagnosis and in the initiation of appropriate treatment can result in severe complications such as acute respiratory distress syndrome (ARDS), septic shock and multisystem organ failure culminating in death. We conducted a prospective, observational study to delineate the clinical profile and predictors of mortality in scrub typhus in adults admitted to the medical wards of a tertiary care, referral hospital in South India over a one-year period. The case fatality rate in this study was 12.2%. Metabolic acidosis (odds ratio [OR] 6.1), ARDS (OR 3.6), altered sensorium (OR 3.6) and shock (OR 3.1) were independent predictors of mortality. It appears that scrub typhus has four possible overlapping clinical presentations: mild disease; respiratory predominant disease; central nervous system predominant disease (meningoencephalitis); or sepsis syndrome. Given the telltale presence of an eschar (evident in 45.5%), the characteristic clinical profile and the dramatic therapeutic response to a cheap, yet effective, drug such as doxycycline, medical practitioners in the region should have ample opportunity to reach an early diagnosis and initiate treatment which could, potentially, reduce the mortality and morbidity associated with scrub typhus.
Chrispal
Anugrah
A
Department of Medicine Unit 2, Christian Medical College, Vellore 632004, Tamil Nadu, India. anugrahchrispal@gmail.com
Boorugu
Harikishan
H
Gopinath
Kango Gopal
KG
Prakash
John Antony Jude
JA
Chandy
Sara
S
Abraham
O C
OC
Abraham
Asha Mary
AM
Thomas
Kurien
K
D000138:Acidosis / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D058186:Acute Kidney Injury / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D015331:Cohort Studies; D004318:Doxycycline / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007194:India / Q000453:epidemiology; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D012285:Orientia tsutsugamushi / Q000302:isolation & purification; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D012307:Risk Factors; D012612:Scrub Typhus / Q000150:complications* / Q000175:diagnosis / Q000188:drug therapy / Q000401:mortality*; D012772:Shock, Septic / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D012959:Socioeconomic Factors; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D004318:Doxycycline