In Search of Scrub Typhus: A Prospective Analysis of Clinical and Epidemiological Profile of Patients from a Tertiary Care Hospital in New Delhi

Introduction: Scrub typhus is a febrile illness caused by Orientia tsutsugamushi which is transmitted by the larval stage of trombiculid mites. It has varied manifestations ranging from mild disease to fatal illness. The classical manifestations include fever, rash, lymphadenopathy and eschar. Serology is the preferred diagnostic tool with indirect immunofluorescence assay (IFA) as the current gold standard. Material & Methods: A total of 229 clinically suspected cases of Scrub typhus from 15th of October 2013 to 15th of October 2015 were enrolled in the study. Clinical, epidemiological and laboratory data of the patients were collected and analysed. The method for diagnosis was IgM immunofluorescence assay. Results: A total of 33 cases (14.4%) of scrub typhus were detected. Most of the cases (87%) presented in the months of September to November. Fever of >39°C was seen in all 33 cases. Rash and eschar were seen in 24.2% and 18.2% cases, respectively. Lymphadenopathy (18.2%), hepatomegaly (48.5%), splenomegaly (21.2%) and icterus (15.2%) were seen in some cases. Pulmonary manifestations were noted in 69.7% of cases. Acute kidney injury (18.2%), encephalitis (21.2%), and myocarditis (15.15%) were the other complications observed. Common haematological abnormalities noted in patients of scrub typhus were anaemia (45.6%), leucocytosis (45.6%), thrombocytopenia (48.5%) and transaminitis (54.5%). 10 cases were treated by azithromycin while doxycycline was used for treatment in 28 cases. Conclusion: The nonspecific symptoms and lack of classical manifestations make the diagnosis of scrub typhus difficult. There is a definite need to increase awareness and heighten the suspicion, especially in the light of increasing number of patients presenting with atypical manifestations.

[1]  J. Peter,et al.  Severe scrub typhus infection: Clinical features, diagnostic challenges and management. , 2015, World journal of critical care medicine.

[2]  P. Newton,et al.  A Systematic Review of Mortality from Untreated Scrub Typhus (Orientia tsutsugamushi) , 2015, PLoS neglected tropical diseases.

[3]  A. Bhargava,et al.  DHR-ICMR Guidelines for Diagnosis & Management of Rickettsial Diseases in India , 2015, The Indian journal of medical research.

[4]  M. Soni,et al.  Analysis of Two Outbreaks of Scrub Typhus in Rajasthan: A Clinico-epidemiological Study. , 2014, The Journal of the Association of Physicians of India.

[5]  J. Peter,et al.  Clinical profile and improving mortality trend of scrub typhus in South India. , 2014, International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases.

[6]  N. Day,et al.  Unresolved problems related to scrub typhus: a seriously neglected life-threatening disease. , 2013, The American journal of tropical medicine and hygiene.

[7]  P. Y. Bhutia,et al.  Outbreak of scrub typhus in the North East Himalayan region-Sikkim: an emerging threat. , 2013, Indian journal of medical microbiology.

[8]  A. Kamath,et al.  Acute kidney injury in scrub typhus , 2013, Clinical and Experimental Nephrology.

[9]  V. Mittal,et al.  Serological evidence of rickettsial infections in Delhi , 2012, The Indian journal of medical research.

[10]  B. Zhu,et al.  Meta-analysis of drug treatment for scrub typhus in Asia. , 2012, Internal medicine.

[11]  S. Mahajan Gastro-intestinal bleeding in scrub typhus. , 2011, The Journal of the Association of Physicians of India.

[12]  N. Rathi,et al.  Rickettsial infections: Indian perspective , 2010, Indian pediatrics.

[13]  S. Chandy,et al.  Scrub typhus: an unrecognized threat in South India – clinical profile and predictors of mortality , 2010, Tropical doctor.

[14]  S. Jayakumar,et al.  Outbreak of scrub typhus in Pondicherry. , 2010, The Journal of the Association of Physicians of India.

[15]  I. Singh,et al.  Rickettsial diseases in Haryana: not an uncommon entity. , 2009, The Journal of the Association of Physicians of India.

[16]  V. Rajagopal,et al.  Serological evidence for wide distribution of spotted fevers & typhus fever in Tamil Nadu. , 2007, The Indian journal of medical research.

[17]  N. Day,et al.  Doxycycline versus Azithromycin for Treatment of Leptospirosis and Scrub Typhus , 2007, Antimicrobial Agents and Chemotherapy.

[18]  N. Day,et al.  Scrub typhus serologic testing with the indirect immunofluorescence method as a diagnostic gold standard: a lack of consensus leads to a lot of confusion. , 2007, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[19]  D. Raoult,et al.  Scrub Typhus in Himalayas , 2006, Emerging infectious diseases.

[20]  D. Mathai,et al.  Scrub typhus among hospitalised patients with febrile illness in South India: magnitude and clinical predictors. , 2006, The Journal of infection.

[21]  M. Gupta,et al.  Investigation of an outbreak of scrub typhus in the himalayan region of India. , 2005, Japanese journal of infectious diseases.

[22]  S. Mahajan,et al.  Scrub typhus. , 2005, The Journal of the Association of Physicians of India.

[23]  D. Raoult,et al.  Outbreak of Scrub Typhus in Southern India during the Cooler Months , 2003, Annals of the New York Academy of Sciences.

[24]  S. Ray,et al.  Reorganization of genera in the families Rickettsiaceae and Anaplasmataceae in the order Rickettsiales: unification of some species of Ehrlichia with Anaplasma, Cowdria with Ehrlichia and Ehrlichia with Neorickettsia, descriptions of six new species combinations and designation of Ehrlichia equi and , 2001, International journal of systematic and evolutionary microbiology.

[25]  N. Myong,et al.  Acute respiratory distress syndrome associated with scrub typhus: diffuse alveolar damage without pulmonary vasculitis. , 2000, Journal of Korean medical science.

[26]  D. Strickman,et al.  Scrub typhus infections poorly responsive to antibiotics in northern Thailand , 1996, The Lancet.

[27]  N. Ohashi,et al.  Phylogenetic position of Rickettsia tsutsugamushi and the relationship among its antigenic variants by analyses of 16S rRNA gene sequences. , 1995, FEMS microbiology letters.

[28]  T. Sheehy,et al.  Scrub typhus. A comparison of chloramphenicol and tetracycline in its treatment. , 1973, Archives of internal medicine.